Статті в журналах з теми "Split weaning"
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1
GILBERTSON, J., P. A. THACKER, and R. N. KIRKWOOD. "THE INFLUENCE OF ALTERED WEANING MANAGEMENT ON PIGLET GROWTH AND SOW REPRODUCTIVE PERFORMANCE." Canadian Journal of Animal Science 69, no. 1 (March 1, 1989): 33–37. http://dx.doi.org/10.4141/cjas89-005.
Повний текст джерелаАнотація:
An experiment was undertaken to investigate the influence of split-weaning of litters 7 d before full weaning on the growth of piglets and the reproductive performance of sows. The litters of 27 Yorkshire × Landrace sows were assigned to be either split-weaned (heaviest piglets removed at 21 d of lactation; n = 13) or to act as controls (all piglets weaned at 28 d of lactation; n = 14). The influence on sow and litter performance was monitored. During lactation, mean sow feed intakes in the split-weaned and control groups were 6.9 ± 0.1 and 6.7 ± 0.2 kg d−1, respectively. The diet was formulated to provide 12.3 MJ DE kg−1 and 15.7% crude protein. Nursing piglets were allowed free access to a 20% crude protein creep feed from 7 d of age. Weaned piglets were fed ad libitum a commercial starter diet containing 18% crude protein. Split-weaning had no effect on either the weaning to estrus interval or subsequent litter size (4.5 ± 0.1 vs. 4.3 ± 0.4 d and 12.7 ± 0.9 vs. 13.0 ± 0.9 pigs, for split-weaned and control sows, respectively). However, while control sows lost weight between 21 and 28 d of lactation, the split-weaned sows gained weight (P < 0.02). There was no treatment effect on body weights of nursing piglets but weaning of the heavy piglets at 21 d resulted in a lower (P < 0.05) body weight at 28 d. On days 21 and 28, four sows from each group were blood sampled via indwelling vena caval cannulae at hourly intervals for 10 h. Also, samples were taken every 15 min for 4 h on these days. No treatment effect was noted for mean serum concentrations of luteinizing hormone (LH) or follicle stimulating hormone (FSH). Similarly, there was no effect on LH pulse frequency or amplitude. It is concluded that, in the absence of excessive sow weight loss or prolonged weaning to estrus intervals, the introduction of a split-weaning regime will not enhance sow or litter performance. Key words: Split-weaning, piglet growth, sow performance
2
Pluske, JR, and IH Williams. "Split weaning increases the growth of light piglets during lactation." Australian Journal of Agricultural Research 47, no. 4 (1996): 513. http://dx.doi.org/10.1071/ar9960513.
Повний текст джерелаАнотація:
The mechanisms of increased growth of small piglets following split weaning were studied using a total of 10 sows and 100 piglets. Sows and their litters were allocated to a treatment group (piglets split-weaned) or control group (no piglets split-weaned). At day 22 of lactation, piglets in each litter were classified as either 'heavy' or 'light', with equal numbers in each group. 'Heavy' piglets were removed from sows at day 22 (s.e.m. 0.17) in split-weaned litters while 'light' piglets remained with their mothers for an extra week. At 29.5 (s.e.m. 0.21) days of age, sows from both split-weaned and control litters were weaned. Milk consumption was estimated between days 16 and 19 and on day 24 of lactation by weighing piglets before and after sucking. During milk letdown, the teats that piglets sucked from were noted. A video recorder was used to determine the frequency of natural sucklings, the proportion of unsuccessful sucklings, and the time taken for piglets to consume milk during ejection, over a 16-h period before and after split weaning. 'Light' piglets in split-weaned litters grew 61% faster (P < 0.001) than their counterparts in control litters and were 15% heavier (P < 0.01) at weaning. This was explained by a 49% increase in milk intake (64 v. 43 g/sucking, P 5 0.001). Increased milk intake was due to multiple teat swapping with an associated longer duration of sucking during letdown. 'Heavy' piglets weaned at 22 days were lighter at 29 days than their counterparts in control litters (P < 0.01). Gains in growth made by 'light' piglets in split-weaned sows over their counterparts in control litters had disappeared by the time pigs were 9 weeks old, and piglets classed as 'heavy' at day 22 of lactation remained heavier ( P < 0.001) at 62 days of age irrespective of treatment.
3
English, P. R., P. R. Bampton, O. MacPherson, M. Birnie, L. J. Bark, and G. R. Foxcroft. "Partial weaning. The growth of smaller piglets remaining on the sow following the earlier weaning of larger litter mates, relative to equivalent piglets in control litters." Proceedings of the British Society of Animal Production (1972) 1987 (March 1987): 19. http://dx.doi.org/10.1017/s0308229600034607.
Повний текст джерелаАнотація:
With progressive reduction in piglet mortality and increase in the number of piglets reared for litter over recent years, there has been interest in weaning the larger piglets in large litters several days prior to the planned final weaning date in an attempt to improve the growth rate and size of the smaller piglets prior to weaning. Such prior removal of larger piglets before their smaller litter mates are weaned is termed ‘partial’ or ‘split’ weaning’ and this practice was evaluated in a controlled experiment in terms of the liveweight gain to weaning of the smaller piglets within the litter.
4
Foxcroft, G. R., P. R. English, P. R. Bampton, O. MacPherson, M. Birnie, and L. J. Bark. "Evaluation of partial weaning and treatment with PG600 at weaning in relation to subsequent reproduction in the sow." Proceedings of the British Society of Animal Production (1972) 1987 (March 1987): 13. http://dx.doi.org/10.1017/s0308229600034553.
Повний текст джерелаАнотація:
’Partial’ or ‘split’ weaning involves the earlier weaning of part of the litter before the normal weaning date. There have been isolated reports which claim that such a practice can reduce final weaning to service and conception interval and increase the size of the subsequent litter. However, these possible effects have not been quantified adequately and accordingly a study was carried out to further evaluate this practice.The study was conducted on a 700 sow commercial unit in Aberdeen-shire with crossbred Large White (LW) x Landrace (LR) sows mated to LW, LR or LW x LR boars. Sows and litters were accomodated in conventional farrowing pens and weaning took place when litters averaged 17 days of age. Following weaning, sows were transferred to dry sow stalls adjacent to boar pens. Newly weaned pigs were transferred to flat-deck nursery accomodation.
5
Abraham, J., and A. K. Chhabra. "Effect of Early Weaning, Split-Weaning and Nursery Feeding Programmes on the Growth of Landrace×Desi Pigs." Tropical Animal Health and Production 36, no. 6 (August 2004): 599–608. http://dx.doi.org/10.1023/b:trop.0000040933.28759.1c.
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Zak, L., GR Foxcroft, FX Aherne, and RN Kirkwood. "Role of Luteinizing Hormone in Primiparous Sow Responses to Split Weaning." Reproduction in Domestic Animals 43, no. 4 (August 2008): 445–50. http://dx.doi.org/10.1111/j.1439-0531.2007.00932.x.
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Terry, Robyn, Karen L. Kind, Paul E. Hughes, David J. Kennaway, Paul J. Herde, and William H. E. J. van Wettere. "Split weaning increases the incidence of lactation oestrus in boar-exposed sows." Animal Reproduction Science 142, no. 1-2 (November 2013): 48–55. http://dx.doi.org/10.1016/j.anireprosci.2013.08.010.
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Willard, Naomi C., Nicole K. Moest, Katherine D. Vande Pol, Alicia Olivio, Caleb M. Shull, Denny McKilligan, and Michael Ellis. "3 Effect of Litter Size and Provision of Supplementary Liquid Milk Replacer During Lactation on Piglet Pre-Weaning Performance." Journal of Animal Science 100, Supplement_2 (April 12, 2022): 2–3. http://dx.doi.org/10.1093/jas/skac064.002.
Повний текст джерелаАнотація:
Abstract Recent increases in litter size in commercial sows have been accompanied by higher pre-weaning mortality (PWM) and lower weaning weights. The objective was to determine effects of litter size and feeding liquid milk replacer during lactation (using an automated feeder) on piglet performance. A split-plot design was used with a 2x2 factorial arrangement of treatments: Milk Replacer (MR; main plot; Unsupplemented vs. Supplemented); Litter Size [LS; sub-plot; Low (2 piglets less than functional teat number) vs. High (2 piglets greater than functional teat number)]. Cross-fostering was carried out at 24 h after birth to create treatment litters with similar gender ratio, proportion of cross-fostered piglets, and average and CV of birth weight. Milk replacer was available from 24 h after birth to weaning. Piglets were weighed on d 1 and 20 (weaning) after birth; all PWM was recorded. Growth data were analyzed using PROC MIXED of SAS; PWM data were analyzed using PROC GLIMMIX. Models accounted for fixed effects of MR, LS, the interaction, and random effects of replicate and replicate by MR interaction. There were no MR by LS interactions (P > 0.05) for any measurement. Supplemented compared with Unsupplemented litters had similar (P > 0.05) litter size at weaning and PWM, but greater (P < 0.05) average piglet and total litter weaning weight (Table 1). The High LS treatment had greater (P < 0.05) litter size and total litter weight at d 1 and weaning, but higher (P < 0.05) PWM and lower (P < 0.05) average piglet weaning weight. In conclusion, supplementing piglets with liquid milk replacer increased weaning weight with no effect on PWM, and increasing litter size above sow teat number had negative effects on both PWM and piglet weaning weight.
9
Huser, J. S., T. E. Kennett, K. J. Plush, W. S. Pitchford, and D. S. Lines. "Neonatal split suckling has no impact on pre- and post-weaning piglet growth." Animal Production Science 55, no. 12 (2015): 1482. http://dx.doi.org/10.1071/anv55n12ab080.
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10
Donovan, Tara S., and Steve S. Dritz. "Effect of split nursing on variation in pig growth from birth to weaning." Journal of the American Veterinary Medical Association 217, no. 1 (July 2000): 79–81. http://dx.doi.org/10.2460/javma.2000.217.79.
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Horn, Nathan L., Adrienne Woodward, Kola Ajuwon, and Layi Adeola. "PSIX-25 Feed and water deprivation at weaning and subsequent heat stress impacts serum and ileal markers of gastrointestinal integrity in nursery pigs." Journal of Animal Science 99, Supplement_3 (October 8, 2021): 496–97. http://dx.doi.org/10.1093/jas/skab235.874.
Повний текст джерелаАнотація:
Abstract Social and environmental stressors impact nursery pig performance and may be linked to gastrointestinal dysfunction. The current experiment was conducted to investigate the impact of feed and water deprivation on serum stress markers and ileal mucosal gene expression in nursery pigs. Mixed-sex pigs were allotted on the basis of IBW (7.0 kg ± 0.89) in a RCBD with treatments in a split-plot arrangement and consisting of the whole-plot factor of with or without a 24-h feed and water deprivation at weaning and the sub-plot factor of with or without a cyclic 3-d heat stress starting 27 d post-weaning. On 1, 27, and 30 d post-weaning one pig from each pen was selected, blood was collected for measurement of serum cortisol, corticotrophin releasing factor (CRF), and endotoxins, and an ileal mucosal scraping was taken and gene expression of claudin 1 (CL-1), occludin (OC), and zonula occludens 1 (ZO-1) were measured by RT PCR. There was an increase (P < 0.05) in serum CRF and endotoxins and a tendency for an increase (P = 0.09) in serum cortisol due to the deprivation 1 d post-weaning. Further, there was a tendency for an increase (P < 0.10) in serum endotoxins and CRF due to the deprivation at 27 and 30 d post-weaning, respectively. Gene expression of CL-1 tended to increase (P = 0.10), and OC decreased (P = 0.05) due to the deprivation 1 d post-weaning. Expression of the OC gene decreased (P < 0.05) due to the deprivation 27 d post-weaning and OC and ZO-1 gene expression tended to decrease (P = 0.07) due to the heat stress 30 d post-weaning. These results show that post-weaning stress events alter serum stress markers and impact intestinal barrier function.
12
P. Asha Latha, I. Ramyasree, and Ch Venkata Seshaiah D. Srinivas Kumar. "Effect of Early and Split Weaning on Carcass traits of Large White Yorkshire Piglets." International Journal of Current Microbiology and Applied Sciences 10, no. 5 (May 10, 2021): 715–18. http://dx.doi.org/10.20546/ijcmas.2021.1005.080.
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Pribadi, Lalu Wira, Rr Agustien Suhardiani, Tahyah Hidjaz, M. Ashari, Happy Poerwoto, Rina Andriati, and Lalu Ahmad Zaenuri. "Pre-Weaning Growth Performance of Boerka (Boer >< Kacang) Crossbred Kids in the Difference Genotype and Birth Types." Jurnal Biologi Tropis 22, no. 3 (September 28, 2022): 1008–17. http://dx.doi.org/10.29303/jbt.v22i3.4146.
Повний текст джерелаАнотація:
Breeding programs to promote the productivity of Indonesian local goats (i.e. Kacang Goats) in various regions have been carried out by cross-breeding with predominant breeds of meat goats in the world such as Boer Goats. Currently, considering that the various genotypes of the cross-bred goat (namely Boerka Goat) have been spread and farmed by various goat farms throughout the country, it is necessary to evaluate the increase in productivity achieved. This study aims to investigate the pre-weaning growth performance of Boerka (Boer x Kacang) Crossbred Kids at different genotypes and birth types. The study was carried out experimentally using 167 Boer x Kacang crossbred kids which was arranged in a Split-Plot Design covering 3 plots of kid genotype, namely: BK (50% Boer, 50% Kacang), BBK (75% Boer, 25% Kacang) , and KBK (25% Boer, 75% Kacang), each with 3 sub-plots of kid birth types, namely single born kid (CT), twin born kid (CK-2), and triplet born kid (CK-3), all including male and female kids. The response variable that measured on pre-weaning growth performance, was observed directly by measuring birth weight (BL), 90-day-old weaning weight (BS90), and daily body weight gain (PBBH) for pre-weaning period. The data is tabulated and analyzed using software “Genstat”. The results showed that BL, BS.90, and pre-weaning PBBH of Boer x Kacang crossbred kids were influenced by genotype (P<0.01) and birth type (P<0.05) of the kids, and differed (P<0.05) between males and females kid. Male kids showed BL, BS90, and Pre-Weaning PBBH 12.88, 9.20, and 9.24% higher than female kids, respectively. Based on the genotype and birth type of the kids, the highest pre-weaning growth performance was shown by single-born male BBK kids, with BL, BS.90 and Pre-Weaning PBBH 3.32±0.33, 13.06±3.46 and 0.114±0.020 kg, respectively.
14
Ribeiro, Marinaldo Divino, José Carlos Pereira, Augusto César de Queiroz, Paulo Roberto Cecon, Edenio Detmann, and José Augusto Gomes Azevêdo. "Performance of dairy calves fed milk, milk replacer or post-weaning concentrate with acidifiers." Revista Brasileira de Zootecnia 38, no. 5 (May 2009): 956–63. http://dx.doi.org/10.1590/s1516-35982009000500024.
Повний текст джерелаАнотація:
The objective of this study was to evaluate the effect of the addition of acidifiers to milk, milk replacer or post-weaning concentrate on the performance and health status of weaning and post-weaning calves. Three experiments were carried out, in the first experiment 62 Holstein × Zebu crossbred calves (males and females), reared from birth to 60 days of age, were distributed and fed milk with or without acidifier. From the third day, the calves were suckled (5L of milk/d) for 56 days, split into two meals. The acidifier was added to milk at the time of feeding. From the second week of calf's age a starter diet (18% of CP) was also offer. In second experiment, the same animals from first experiment, but from 61 to 120 days of age were distributed and fed (2 kg/d) post-weaning concentrate (18% of CP) with or without acidifier and Cynodon dactylon hay ad libitum. In third experiment, 16 male Holstein × Zebu crossbred calves, reared from birth to 60 days of age, were distributed and fed milk replacer with or without acidifier. The acidifier used in the first and third experiments was composed by the citric, lactic, fumaric, and phosphoric acids, and vitamin C (liquid diet); and by betaglucans, flavonoides, linoleic and oleic and citric acids, and vitamin C (solid diet). The addition of acidifier to milk or to post-weaning concentrate did not affect the dry matter (DM) and CP intakes, which were 818 and 196; 1740 and 217 g/d respectively. Similarly, it did not show high average daily gains, with 525 and 513 g/d, respectively. The addition of acidifiers to milk replacer showed results similar to those observed in calves fed milk. Therefore, the use of acidifiers in milk, milk replacer or in the post-weaning concentrate did not result in beneficial effects for calves.
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Hardiman, R., and H. A. M. van der Steen. "Evaluation of three strawflow® systems as alternatives to traditional flatdeck accommodation in pigs." Proceedings of the British Society of Animal Production (1972) 1994 (March 1994): 192. http://dx.doi.org/10.1017/s0308229600027379.
Повний текст джерелаАнотація:
The strawflow® system is designed to provide pigs with free access to straw without the operational and agricultural constraints of a deep bedded system and could provide an alternative type of weaning accommodation. A trial was conducted to evaluate the potential of three different strawflow® systems. These differed only in means of heating and ventilation.Two trials were conducted consisting of twenty four and twelve weekly groups of pigs. Eighty pigs were split sex weaned into four strawflow® pens in the same room, on a weekly basis, and remained in the system for forty days. All other pigs to be weaned that week were weaned into the flatdecks. (8827 pigs total)An average weaning weight was recorded for each batch of piglets moved into the strawflow® and flatdecks and each pig was individually weighed on leaving a system. Feeding regime was the same in each system with a creep feed for approximately one week post weaning before moving onto a grower ration for the remainder of the trial. All food given to a flatdeck room and one side of a room in the strawflow® building was recorded.
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van Barneveld, R. J., and R. J. E. Hewitt. "Reducing variation in pork production systems through maternal and pre- and post-weaning nutrition strategies." Animal Production Science 56, no. 8 (2016): 1248. http://dx.doi.org/10.1071/an15396.
Повний текст джерелаАнотація:
Variation is inherent in any biological system and is a challenge to manage in modern pork-production businesses. In the case of the growing and finishing herd, inherent variation within a population of pigs represents a significant cost as a result of the need to select on farm to meet market specifications, poor matching of diet specifications to nutrient requirements, grading losses, higher pre-weaning mortality, and challenges associated with health management. As a consequence, any management practice that can be applied to reduce variation at the point of sale has the potential to improve the profitability and overall efficiency of a pig enterprise. The present paper considers nutritional interventions of sows during gestation, lactation and the weaning to oestrus interval to minimise inherent variation in the progeny and then pre- and post-weaning nutrition of piglets to limit further variation. Prior to birth, there are many factors that can influence variation in the birthweight and growth potential of the progeny. In gestating sows, dietary energy will not influence variation in birthweight, but supplementation with free arginine and glutamine will reduce variation in birthweight of piglets born and piglets born alive. In lactating sows, maintenance of feed intake to optimise milk production and minimise weight loss of the sow during lactation not only minimises variation in progeny weight at weaning, but enhances subsequent birthweight heterogeneity due to the influence of the sow’s metabolic status on follicle and oocyte quality. Supplementation with dextrose during the weaning to oestrus interval can also reduce variation in birthweight due to a pronounced effect on plasma glucose and insulin concentrations. Prior to weaning, light weight piglets appear to have an enhanced capacity for growth compared with their larger counterparts. To this end, split suckling has been shown to reduce weaning-weight variation, despite no effect on average growth rate or weaning weight for litters with nine piglets or more born alive. Supplemental milk before weaning has reduced variation in weaning weights, but creep feeding has proved equivocal in this regard. Post-weaning, it appears that remedial feeding strategies will do little to improve the growth potential of light-weight pigs, and while high specification diets may contribute to a slight reduction in variation at slaughter, this strategy is unlikely to be economically viable. As with many aspects of commercial pork production, it would seem that the greatest potential to reduce variation in the slaughter weight of market pigs vests with careful management of gestating and lactating sows, with some potential for dietary interventions to further reduce variation in birth and weaning weights.
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van Leeuwen, JJJ, M. Verhoeven, I. van der Heden-van Noort, S. Kranenbarg, B. Kemp, and NM Soede. "Split-weaning Before Altrenogest Synchronization of Multiparous Sows Alters Follicular Development and Reduces Embryo Survival." Reproduction in Domestic Animals 47, no. 4 (October 12, 2011): 530–36. http://dx.doi.org/10.1111/j.1439-0531.2011.01913.x.
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Vesseur, P. C., B. Kemp, L. A. den Hartog, and J. P. T. M. Noordhuizen. "Effect of split-weaning in first and second parity sows on sow and piglet performance." Livestock Production Science 49, no. 3 (September 1997): 277–85. http://dx.doi.org/10.1016/s0301-6226(97)00043-2.
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Matte, J. "The effect of interrupted suckling and split-weaning on reproductive performance of sows: a review." Livestock Production Science 30, no. 3 (February 1992): 195–212. http://dx.doi.org/10.1016/0301-6226(92)90069-g.
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Rudd, A. R., and P. H. Simmins. "Consequences of diet fed ad Libitum to the Farrowing and Lactating Crated Sow." Proceedings of the British Society of Animal Production (1972) 1994 (March 1994): 152. http://dx.doi.org/10.1017/s0308229600026970.
Повний текст джерелаАнотація:
Ad libitum feeding of lactating sows might ease the feeding management of group and individually housed sows. In this study a commercial feeding regime was compared with diet fed ad libitum to sows crated during the farrowing and lactating period. It was part of a larger project examining alternative farrowing systems.In separate experiments, two feeding regimes were compared. The experimental building contained 5 farrowing crates. The first 10 sows were fed at commercial levels (2.2 kg/day before farrowing & 5.7 kg/day for litter size n=10, ± 0.4 kg per piglet). This was split between meals at 0700 and 1530 daily, fed via a trough at the front of the crate. For the following 30 sows the five farrowing crates were modified by the addition of an ad libitum hopper to the front of the farrowing crate. All animals received an identical lactating diet (DE=13.2MJ/kg, CP=17.9%) throughout the study. Sows entered the farrowing accommodation at day 110±4 of gestation. They remained crated throughout the experiment until weaning at 24±4 days post-partum. Measurements of sow entry and weaning weights were taken, together with records of sow feed intake and individual piglet weights at birth and weaning.
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Tolosa Russi, Andres F., Michael Ellis, Omarh Mendoza, Caleb M. Shull, and Clint Schwab. "80 Effects of dietary standardized ileal digestible lysine level in the nursery period and number of dietary phases in the grow-finish period on wean-to-finish growth performance of pigs." Journal of Animal Science 98, Supplement_3 (November 2, 2020): 69–70. http://dx.doi.org/10.1093/jas/skaa054.124.
Повний текст джерелаАнотація:
Abstract The objective was to determine if feeding differing levels of dietary standardized ileal digestible lysine (SID Lys) during the nursery phase influenced the growth performance response to the number of dietary phases fed in the grow-finish period. A split-plot design was used with a 3×2 factorial arrangement of the following treatments: 1) SID Lys level nursery period: Control (SID Lys at requirement) vs. Restricted (0.2 g/kg SID Lys below Control) vs. Excess (0.1 g/kg SID Lys above Control; 2) Number of Dietary Phases in grow-finish: 3 vs. 5. Diets were formulated to meet NRC (2012) requirements, except for SID Lys during the nursery period. The study was carried out over the nursery [weaning (21±2 d; 5.8 ± 0.05 kg BW) to wk 9 post-weaning] and grow-finish [wk 9 to 19 post-weaning (112 ± 3.7 kg BW)] periods using 4,356 pigs housed in single-sex groups of 44 pigs, at a floor space of 0.30 m2/pig and 0.62 m2/pig in nursery and grow-finish periods, respectively. Data were analyzed using PROC MIXED of SAS; pen was the experimental unit. The model included fixed effects of SID Lys level (main plot), Number of Dietary Phases (split plot), their interaction, and random effects of block and block by SID Lys level interaction. There were no treatment interactions (P > 0.05). The Restricted Lys treatment reduced (P < 0.05) ADG and G:F in the nursery period compared to other treatments, but had no effect on these measurements in the grow-finish or wean-to-finish periods. There was no effect (P > 0.05) of the number of dietary phases on growth performance in grow-finish. In conclusion, feeding low levels of Lys in the nursery reduced nursery but not wean-to-finish growth performance; reducing the number of dietary phases in grow-finish from 5 to 3 had no impact on growth performance.
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Furniss, S. R., B. Sutton, and S. J. Furniss. "An evaluation of split litter suckling as a method of reducing pre-weaning mortality in pigs." Proceedings of the British Society of Animal Production (1972) 1986 (March 1986): 127. http://dx.doi.org/10.1017/s0308229600016330.
Повний текст джерелаАнотація:
Pre-weaning mortality in pigs in the United Kingdom is estimated to be 11.6% ie the loss of around 2 million piglets every year. If only the cost of piglet production is considered this represents a loss to the industry of approximately £28 million each year. In fact the revenue foregone from finished pigs is much greater (MAFF,1985).Over 50% of the losses of liveborn piglets occur in the first 48 to 72 hours after birth. Around 75% of mortalities are due to the two, often related causes, overlying by the dam and starvation (English and Morrison, 1984).Mortality is inversley related to birth weight, small piglets being affected by competition from their larger litter mates and having lower energy reserves. To reduce piglet mortality care must therefore be concentrated, especially on small weakly piglets in the first 48 hours of life.
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Cardoso, Leandro Lunardini, Patrcia Biegelmeyer, and Fernando Flores Cardoso. "Genotype x environment interaction on post-weaning performance and carcass in beef cattle." Semina: Ciências Agrárias 38, no. 1 (March 2, 2017): 481. http://dx.doi.org/10.5433/1679-0359.2017v38n1p481.
Повний текст джерелаАнотація:
We analyzed average daily gain from weaning to yearling (ADG), yearling weight (YW), rib eye area, and subcutaneous fat thickness of 91 Angus, Hereford, Caracu, and Nellore cattle, and their crosses. The animals were split into two grazing groups: improved natural grassland (n = 47) and natural grassland (n = 44). The environment was found to influence all traits, and the highest measures of performance were observed in improved natural grassland. The genetic group x environment interaction was verified only for ADG and YW (P < 0.05). We found the best performance trait averages for crossbreeds of Bos taurus and Bos indicus. In addition, we found genetic x environment interaction effects in growing traits and Longissimus muscle area between the evaluated genotype groups. Finally, we found that between the evaluated genotype groups, subcutaneous adipose fat was not influenced by the environment.
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Cabrera, Rafael A. "129 The effect of Activo Liquid supplemented via the water against Mecadox 50 on nursery pig’s growth performance and survival." Journal of Animal Science 97, Supplement_2 (July 2019): 73. http://dx.doi.org/10.1093/jas/skz122.134.
Повний текст джерелаАнотація:
Abstract The objective of this study was to compare Activo Liquid supplemented via the water agaisnt Mecadox 50 on nursery pigs’ growth performance and survival. Activo Liquid is a combination of secondary plant compounds plus organic acid (antimicrobial) supplemented in the water to support gut health and improve performance. The study design of this trial was a Split Plot with 36 replicates (9 replicates/treatment) with 10 pigs/pen. Pigs were allotted by a Randomized Complete Block Design by weight at weaning. Pigs were around 5.7 kg and 19 days of age average on body weight and weaning age, respectively. The nursery houses were not washed for two turns to expose the animals to serious pathogens. The data were analyzed by analysis of variance with pen as the experimental unit. Significant differences were established by P < 0.05. Treatments were Control with 50g/ton of Mecadox for all nursery phases and three Activo Liquid treatments (6 oz per 128 gallon of drinking water administered either for 3, 5 or 7 days post-weaning). A typical nursery feeding program was followed: Phase 1 from d 0 to d 7, Phase2 from d 8 to d 21 and Phase 3 from d 22 to d4 2. They contain 23%, 21% and 19% crude protein respectively. The results showed no significant difference on final body weight among the treatments. All Activo treatments had improved (P < 0.05) feed conversion (Feed:Gain) when compared with the medicated treatment. Activo Liquid 5d treatment post-weaning had numerically lower mortality when compared with all the other treatments. In conclusion, the results of this trial showed that the supplementation of Activo Liquid for 5 d post-weaning at 6 oz/128 gallon of water can safely replace Mecadox 50 g/ton. More research is needed to validate the repeatability of these results and understand Activo Liquid’s mode of action as a powerful antimicrobial.
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Cauble, Reagan, Elizabeth Palmer, Jeremy Powell, Matthew Cravey, Jana Reynolds, and Elizabeth Kegley. "PSXIV-24 Immune function and growth performance in beef calves supplemented during backgrounding with live yeast and yeast cell wall in combination with supplemented dams." Journal of Animal Science 97, Supplement_3 (December 2019): 446–47. http://dx.doi.org/10.1093/jas/skz258.879.
Повний текст джерелаАнотація:
Abstract Live yeast and yeast cell wall products potentially improve health and performance in cattle during the stocker and feedlot phases. Therefore, the objective of this study was to investigate yeast-product supplementation during late gestation through 88 d of age, and(or) a 42-d backgrounding period on immune function and growth performance. Late gestation cows (n = 97) were assigned randomly to treatment: 1) supplement without yeast (CON) or 2) supplement with yeast products (YP). At weaning, calves from each dam treatment (CON or YP) were pooled by dam treatment and stratified based on BW, sex, dam parity, and sire and split into 8 pens within dam treatment. Pens were assigned randomly to 1 of 2 backgrounding treatments (CON or YP) such that a total of 4 pens/treatment existed. Treatments included: 1) dam YP, calf YP, 2) dam YP, calf CON, 3) dam CON, calf YP, and 4) dam CON, calf CON. Calves were fed 2 kg/d of grain and yeast (5 g/d) was provided in a top-dress (ground corn plus YP). Weaning weights (P = 0.99) and backgrounding ADG (P = 0.29) did not differ. Total ruminal VFA concentrations, sampled on d 0 and 42 post-weaning, were increased in calves from dams supplemented with YP (P = 0.04). There were no effects of treatment (P ≥ 0.32) on molar proportions of acetate and propionate. Haptoglobin (P ≥ 0.49) and neutrophil:lymphocyte ratio (P ≥ 0.46) were not influenced by treatment but were affected by day (P < 0.01). While there was no effect of YP (P = 0.73) on BVD titers, there was a day effect (P < 0.01) where titers were greatest on d 28 and least on d 0. Post-weaning yeast supplementation in combination with dam supplementation did not improve calf immune function or performance during a 42-d backgrounding period.
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Zivkovic, Vladimir, Marija Gogic, Nenad Stojiljkovic, Tamara Stamenic, Cedomir Radovic, Nikola Delic, and Aleksandar Stanojkovic. "Effect of using vanilla sweet aroma in diets for weaning pigs." Biotehnologija u stocarstvu 38, no. 2 (2022): 115–23. http://dx.doi.org/10.2298/bah2202115z.
Повний текст джерелаАнотація:
The trial was conducted on 108 piglets of crossbreeds Landrace x Large White. Aim of this study was to determine influence of this aroma on production parameters of growing pigs. Whole trial was in total 57 days, and it was split in three trial periods. Piglets were weaned on day 27, when the trial started. First trial period was 18 days (27-44 day), second was 28 days (45-72 day) and third was 11 days (73-83 day). The control groups received standard farm mixtures, and the trial groups had added aroma Vanilla Sweet in different concentrations (0.02; 0.04%, respectively). During the first period, there was statistical difference (p<0.05) in all three prameters between the groups. Feed intake (FI), average daily gain (ADG) and feed conversion (FCR) differed between C and T1 group. T1 had best ADG of 261.53 g/d and FCR of 1.89 g/g. In the second period statistical significance was noted in FI and ADG, between T1 and other two groups. T1 had lower FI and ADG, but better FCR compared to control group. In the final period second experimental group had the best results in both FI (1309.29 g/d) and ADG (696.43 g/d). And eventualy for whole trial T2 had better results in all three production parametars compared to other two trial groups. In general, obtained results showed that use of Vanilla sweet aroma can be recommended in the nutrition of weaned pigs. Further investigation should be conducted to determine the effect of this flavour on fatteners.
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Ciro Galeano, Johana Andrea, Albeiro López Herrera, and Jaime Parra Suescún. "The probiotic Enterococcus faecium modifies the intestinal morphometric parameters in weaning piglets." Revista Facultad Nacional de Agronomía Medellín 69, no. 1 (January 1, 2016): 7803–11. http://dx.doi.org/10.15446/rfna.v69n1.54748.
Повний текст джерелаАнотація:
Global trends for animal production have seen a decrease in the use of antimicrobial compounds in feed, generating the need to implement new nutritional strategies that stimulate growth and promote intestinal health. This study aimed to determine whether the addition of E. faecium in drinking water improves intestinal morphometric parameters in post- weaning pigs compared with the probiotics strains L. acidophilus and L. casei on days 1 (21 days of age), 15 and 30 postweaning. The small intestine was completely removed to evaluate the morphometric parameters (length and width of villi and crypts) in the different intestinal segments (duodenum, jejunum, and ileum). They were fed for 30 days with two diets: commercial diet with or without antibiotics. The different probiotics, L. acidophillus, L. casei and E. faecium, were administered in the drinking water of the animals that consumed the commercial diet without antibiotics. A randomized block design in split-plot arrangement was used. There was a significant increase (P<0.01) in the width and length of villi, and a decrease (P<0.01) in the values obtained for the width and depth of crypts in the animals that consumed E .faecium, as compared to those that consumed the diet with addition of antibiotics. The use of probiotics, especially E. faecium, is a nutritional treatment strategy when antimicrobial compound are used, improving the intestinal morphometric parameters and, at the same time, the digestive and productive parameters of the animals. Work is in progress to investigate the effects of probiotic supplementation on the mofication of gut microbiota of post-weaning piglets.
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Beck, Paul A., Earl Ward, Scott Clawson, Brian Pugh, and Rodney Farris. "29 Demonstrating the Effects of Deworming and Implanting Weaned Calves for Retained Ownership on Pasture in Eastern Oklahoma." Journal of Animal Science 98, Supplement_2 (November 1, 2020): 6. http://dx.doi.org/10.1093/jas/skz397.013.
Повний текст джерелаАнотація:
Abstract The majority of cow-calf producers in Oklahoma sell their calves at weaning. Preconditioning and retained ownership through the stocker phase provides economic benefits to these operations. The objectives of this demonstration were to illustrate the benefits of growth promoting technologies for calves post-weaning. Calves (n = 39 heifers and 24 steers; BW = 229 ± 23.9 kg) from the OSU Eastern Research Station cowherd were weaned on day – 20 (April 15) and preconditioned. On day 0 (May 6), calves (n = 20 heifers and 12 steers) were treated for internal parasites (Dectomax, Zoetis Animal Health) and evenly allocated to 2 Bermudagrass/tall fescue pastures (9.5 ± 1.42 ha) for 143 days. The remaining calves (n = 19 heifers and 12 steers) were not treated for parasites and allocated to 2 pastures (9.1 ± 1.42 ha). In each pasture, ½ of the calves of each sex were implanted (Synovex-S or Synovex-H, Zoetis). Calves dewormed on day 0 and were dewormed again on day 70 (July 16). Data were analyzed as a split plot experimental design with dewormer treatment as the main plot and calf sex and implant treatment were the split plots. There were no interactions among calf sex, deworming, and implants (P ≥ 0.42). Steers were heavier (P < 0.01) than heifers throughout the summer, but did not have an advantage in gain performance (P ≥ 0.22). Deworming did not impact (P = 0.44) overall growth performance of calves, but did numerically (P = 0.18) increase ADG from day 71 to 143 by 0.15 kg/d. Growth promoting implants increased (P = 0.03) daily gains by 0.09 kg/day in the early summer and over the entire summer by 0.07 kg/day (P < 0.01). The combination of deworming and implants increased (P = 0.01) season long ADG by 0.11 kg/day over unimplanted controls. This demonstration was used to illustrate the potential that growth promoting implants and deworming provides for economically beneficial performance enhancement for retained stocker calves on mixed grass pasture.
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Hinch, GN, JJ Lynch, JV Nolan, RA Leng, BM Bindon, and LR Piper. "Supplementation of high fecundity Border Leicester x Merino ewes with a high protein feed: its effect on lamb survival." Australian Journal of Experimental Agriculture 36, no. 2 (1996): 129. http://dx.doi.org/10.1071/ea9960129.
Повний текст джерелаАнотація:
Two hundred and fifty Border Leicester x Merino ewes (40% heterozygous for the Booroola Fec B gene) were used in an experiment, replicated over 2 years, to examine the effects of cottonseed meal-based supplementation on lamb survival, birth, marking and weaning weight, as well as, liveweight and fleece characteristics of ewes. From 50 to 100 days of pregnancy, half of the ewes were supplemented with 80 g/head.day. The supplemented group was then split according to litter size and, until 30 days after lambing, were offered pellets at 80, 160 and 220 g/head .day, respectively, for ewes bearing single, twin and triplet (or more) lambs. Over the 2 years, ewes averaged 2.11 lambs per parturition and supplementation significantly increased lamb survival to weaning (73 v. 58%) with no interaction with litter size. Although supplementation had a positive effect on birth weight of all but twins, the effects of supplementation on survival were independent of birth weight effects. Significant effects of year, sire breed and litter size on lamb survival and birth weight were also noted. No effects of supplementation were apparent on lamb growth while ewe age, sire breed, sex and rearing rank all significantly influenced growth rates. Ewe weights, fleece weights and staple strength were significantly influenced by year, ewe age and litter size but not by supplementation. These findings indicate the benefits to lamb survival of providing a 'bypass' protein supplement to high fecundity flocks even when ewes are grazing good quality pastures.
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Williams, Hadley, Leandro Del Tuffo, Mike D. Tokach, Joel M. DeRouchey, Jason C. Woodworth, Steve S. Dritz, Robert D. Goodband, et al. "PSIX-7 Effects of a dietary seaweed product on sow progeny performance, fecal consistency, and fecal microbiota during gestation, lactation, nursery and grow-finish periods." Journal of Animal Science 98, Supplement_3 (November 2, 2020): 189–90. http://dx.doi.org/10.1093/jas/skaa054.335.
Повний текст джерелаАнотація:
Abstract This study evaluated the effects of providing a selected mix of brown, red and green seaweeds (OceanFeed® Swine; Ocean Harvest Technology, Galway, Ireland) to sows during gestation and lactation and progeny during nursery and grow-finish periods on growth performance, fecal consistency, and microbiota composition. Twenty-eight sows and litters were used from d 30 of gestation until weaning. Sow treatments consisted of a control diet or diet supplemented with OceanFeed Swine (OFS) at 0.50% in gestation and 0.66% in lactation. At weaning, 360 pigs from these sows were used from d 0 to 56 and 57 to 156 in nursery and grow-finish periods, respectively, in a split-plot design. Treatments were a control diet or a diet supplemented with OFS at 0.75% in the nursery and grower phase (5.5 to 34 kg and 34 to 59 kg respectively) and 0.5% in the finisher phase (59 to 127 kg). Maternal OFS supplementation did not improve (P >0.10) sow or litter performance. There was no evidence (P >0.10) for main effects or interactions for nursery and finishing performance. On day 56 after weaning, there was an increased proportion of pigs exhibiting the families Peptostreptococcaceae and Veillonellaceae in fecal samples when fed OFS in the nursery and originating from OceanFeed OFS-fed sows. Pigs from this treatment combination also had increased mean number of species detected within the families Ruminococcaceae and Lachnospiraceae and had lower mean number of species detected within the family Fusobacteriacea. In the finishing period, no evidence for main effects or interactions (P >0.10) were observed on overall growth performance. In summary, addition of OFS in gestation, lactation, and nursery-finishing phases had no consistent effect on sow or litter performance; however, there were relative increases in beneficial bacteriain fecal microbiota, including the butyrate-producing families Ruminococcaceae and Lachnospiraceae that warrant further investigation.
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Nalbert, Czopowicz, Szaluś-Jordanow, Moroz, Mickiewicz, Witkowski, Markowska-Daniel, Puchała, Bagnicka, and Kaba. "Effect of Immediately-After-Birth Weaning on the Development of Goat Kids Born to Small Ruminant Lentivirus-Positive Dams." Animals 9, no. 10 (October 17, 2019): 822. http://dx.doi.org/10.3390/ani9100822.
Повний текст джерелаАнотація:
A longitudinal study was carried out to investigate the influence of two different rearing systems of young kids on their development to sexual maturity. Kids born to small ruminant lentiviruses-infected (SRLV) female goats were split into two groups: the immediately-after-birth weaned group and the unweaned group. Kids’ body weight (BWT) was measured before the first consumption of colostrum, and then at the age of one week, and one, two, four, and seven months. The relationship between the rearing system and BWT at each age was investigated using mixed linear models adjusted for potential confounders. The mean BWT of kids of the immediately-after-birth weaned group was significantly lower at the age of one week, one month, and two months, and then the difference became insignificant. The mean daily body weight gain (DWG) was significantly lower in the immediately-after-birth weaned group during the whole first month of life, but then DWG in both groups became equal. Crude mortality rate did not differ significantly between groups. This study shows that weaning kids immediately after birth does not appear to have any negative impact on kids’ development except transient growth retardation, which is fully compensated until they reach sexual maturity.
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Lewis, T. W., J. A. Woolliams, and J. Wiseman. "An investigation into the genetic relationship of reproduction traits of sows under different mating method (artificial insemination versus natural service)." Proceedings of the British Society of Animal Science 2005 (2005): 54. http://dx.doi.org/10.1017/s1752756200009650.
Повний текст джерелаАнотація:
Falconer and MacKay (1996) note that the measurement of a trait in two different environments may be considered as two traits rather than one. In this way it is possible, through the calculation of genetic correlations, to estimate to what extent the two measurements under different conditions are in fact the same characteristic and are determined by the same genes. The widespread use of AI in pig production has faltered due to problems with dilution and cryopreservation of semen and yet an industry split, where breeders and nucleus herds use AI extensively but multipliers and commercial producers do not, is becoming apparent. Reproductive traits are increasingly seen as an important component of overall pig production and while the genetic correlation between reproductive and production traits has been explored, little work has focused on the genotype by environment interaction of such fertility traits. The present study reports the genetic relationship of number born alive (NBA) in litters conceived naturally and by AI, and in rate of weaning to first service (WTFS-1).
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Blomme, Allison K., Nick Weihs, James Jolliff, and Trey A. Kellner. "120 Impact of a Two-phase Lactation Feeding Program on Farrowing and Weaning Performance of Sows." Journal of Animal Science 99, Supplement_1 (May 1, 2021): 56–57. http://dx.doi.org/10.1093/jas/skab054.095.
Повний текст джерелаАнотація:
Abstract The U.S. Pork Industry uses a one-phase lactation feeding program based on logistical constraints and ease. The objective of this experiment was to quantify the sow performance differences between a one-phase and two-phase lactation feeding program to allow pork producers to calculate the economics of switching to a two-phase lactation feeding program. 257 gilts and sows (PIC 1050; Hendersonville, TN) were randomly assigned to a two-phase or one-phase lactation feeding program. Animals on the one-phase treatment were fed a typical lactation diet (2.55 Mcal/kg NE, 12.7% NDF, 0.99% SID Lys) for the duration of the experiment. Animals on the two-phase treatment were fed a high-fiber, lower-lysine transition diet (2.35 Mcal/kg NE, 18.5% NDF, 0.65% SID Lys) from the time they were loaded into the farrowing room until switching to the lactation diet on d 3 post-farrowing. From loading to farrowing, animals on both treatments were fed 1.82 kg/d, split between 2 meals at 630 and 1530 h. Daily feed amount was increased on the farrowing day and the 2 subsequent days (2.73, 4.09, 5.45 kg) until allowed ad libitum access to the lactation feed for both treatment groups on the third day after farrowing. Data were analyzed using Proc MIXED (SAS 9.4; Cary, NC) with treatment as the main effect and sow as the experimental unit. Comparing treatments, no significant differences on total born (one-phase = 16.2 vs. two-phase = 16.0, pigs/litter), live born (one-phase = 14.6 vs. two-phase = 14.4, pigs/litter), stillborn rate (one-phase = 8.1% vs. two-phase = 7.4%), number weaned (one-phase = 12.1 vs. two-phase = 11.9, pigs/litter), or weaning weight (one-phase = 5.67 vs. two-phase = 5.71, kg/pig; P ≥ 0.37) were detected. In conclusion, a two-phase lactation feeding program did not impair sow performance can be utilized to reduce lactation feed costs by $0.42/female/lactation cycle.
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Menegat, Mariana B., Joel M. DeRouchey, Jason C. Woodworth, Steve S. Dritz, Mike D. Tokach, and Robert D. Goodband. "Effects of Bacillus subtilis C-3102 on sow and progeny performance, fecal consistency, and fecal microbes during gestation, lactation, and nursery periods1,2." Journal of Animal Science 97, no. 9 (July 10, 2019): 3920–37. http://dx.doi.org/10.1093/jas/skz236.
Повний текст джерелаАнотація:
Abstract This study evaluated the effects of providing a dietary probiotic, Bacillus subtilis C-3102, to sows during gestation and lactation and to progeny after weaning on performance, fecal consistency, and fecal microbes. For the sow portion of the study, 29 sows and litters were used from day 30 of gestation until weaning. Sow treatments consisted of control diet or probiotic diet with B. subtilis C-3102 at 500,000 cfu/g of gestation feed and 1,000,000 cfu/g of lactation feed. For the nursery portion of the study, 358 weaned pigs, progeny of sows on study, were used in a 42-d nursery study. Nursery treatments consisted of control diet or probiotic diet with B. subtilis C-3102 and prebiotics at 500,000 cfu/g of nursery feed. Treatments were arranged in a split-plot design with sow treatment (control or probiotic diet) as main plot and nursery treatment (control or probiotic diet) as subplot. Performance, fecal consistency by fecal score method, and fecal microbes by isolation and enumeration method were assessed. In lactation, probiotic-fed sows tended (P = 0.057) to have increased feed intake, but it did not improve (P > 0.05) sow or litter performance in lactation. In the nursery, there were no (P > 0.10) interactions or main effects of sow or nursery treatments on overall growth performance. However, pigs born from control-fed sows had greater (P < 0.05) average daily gain, average daily feed intake, and body weight in late nursery than pigs born from probiotic-fed sows. Fecal score evaluation of nursing and nursery pigs indicated no influence (P > 0.05) of sow or nursery treatments on fecal consistency. Fecal microbial analysis revealed a modest modification in fecal microbial population by increasing (P < 0.05) the number of total Bacillus sp. in probiotic-fed sows and nursery pigs. Nursing piglets born from probiotic-fed sows carried over (P < 0.05) this modification in fecal microbial population preweaning. In conclusion, providing a probiotic based on B. subtilis C-3102 to sows during gestation and lactation and to progeny after weaning did not elicit noteworthy improvements in performance or fecal consistency, but there was a benefit on sow lactation feed intake. Fecal microbial analysis indicated a maternal-progeny intestinal microbiota relationship with pigs born from probiotic-fed sows displaying similar fecal microbial population as sows. However, pigs born from probiotic-fed sows demonstrated reduced growth rate and feed consumption in late nursery.
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Li, Yihang, Karina Matos, Mrigendra Rajput, and Adam James Moeser. "191 Early weaning in pigs induces long-term alterations in intestinal nutrient transporter function and expression partially via beta adrenergic enteric neural receptors." Journal of Animal Science 97, Supplement_2 (July 2019): 112–13. http://dx.doi.org/10.1093/jas/skz122.199.
Повний текст джерелаАнотація:
Abstract Early weaning (EW) has negative impacts on performance and health that persist from wean-to-finish. The mechanisms linking EW and lifetime performance reductions are poorly understood. The objective of this study was to investigate whether EW influences the long-term development of intestinal epithelial nutrient transporter function and expression and the potential mechanisms. Yorkshire gilts were split-weaned from their sows at 15 d (EW) or 28 d of age (Late Weaning; LW) and transferred to an on-site nursery room. All pigs received the same diets in a standard phase feeding program and were euthanized at 75 d of age. Mid-jejunum and distal ileum were mounted on Ussing chambers to evaluate Na+-dependent glucose and amino acid (AA) transporter function, measured as nutrient-induced changes in short circuit current (Isc). EW gilts exhibited reduced capacity for electrogenic transport of glucose (by ~30%; P < 0.05) and glutamate, glutamine, and alanine by (~ 30–35%; P < 0.05), compared with LW pigs. In contrast, jejunal and ileal lysine transporter function was upregulated (by 110% and 25%, respectively; P < 0.05) in EW pigs. Epithelial expression for glucose transporter (SGLT1) was reduced (P < 0.05) while glucose/fructose transporter (GLUT2), fructose transporter (GLUT5) and lysine transporters (B0AT1, CAT1, and ATB0, +) were enhanced in the EW jejunum. No differences observed in villus morphology between EW and LW pigs. Pretreatment of ileal mucosa on Ussing chambers with the Na+ channel blocker (Tetrodotoxin) or the β-adrenergic receptor blocker (Propranolol) augmented glucose, lysine and alanine transporter function in EW but not LW pigs. Together, these data show that EW in gilts induces lasting and divergent alterations in intestinal nutrient transporter function and expression which is mediated in part by the enteric nervous system and β-adrenergic receptor pathways. These new findings may explain why EW pigs exhibit lasting deleterious impacts on performance. Further mechanism-based investigations could reveal new targets for optimizing performance in EW pigs throughout the production lifespan.
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Mahan, D. C. "Effect of weight, split-weaning, and nursery feeding programs on performance responses of pigs to 105 kilograms body weight and subsequent effects on sow rebreeding interval." Journal of Animal Science 71, no. 8 (August 1, 1993): 1991–95. http://dx.doi.org/10.2527/1993.7181991x.
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Serrano, Alba, Madhu Asnani-Kishnani, Charlene Couturier, Julien Astier, Andreu Palou, Jean-François Landrier, Joan Ribot, and M. Luisa Bonet. "DNA Methylation Changes are Associated with the Programming of White Adipose Tissue Browning Features by Resveratrol and Nicotinamide Riboside Neonatal Supplementations in Mice." Nutrients 12, no. 2 (February 12, 2020): 461. http://dx.doi.org/10.3390/nu12020461.
Повний текст джерелаАнотація:
Neonatal supplementation with resveratrol (RSV) or nicotinamide riboside (NR) programs in male mice brown adipocyte-like features in white adipose tissue (WAT browning) together with improved metabolism in adulthood. We tested the involvement in this programming of long-term epigenetic changes in two browning-related genes that are overexpressed in WAT of supplemented mice, Slc27a1 and Prdm16. Suckling mice received orally the vehicle, RSV or NR from postnatal days 2-to-20. After weaning (d21) onto a chow diet, male mice were habituated to a normal-fat diet (NFD) starting d75, and split on d90 into continuation on the NFD or switching to a high-fat diet (HFD) until euthanization on d164. CpG methylation by bisulfite-sequencing was analyzed on inguinal WAT. Both treatments modified methylation marks in Slc27a1 and Prdm16 and the HFD-dependent dynamics of these marks in the adult WAT, with distinct and common effects. The treatments also affected gene expression of de novo DNA methylases in WAT of young animals (euthanized at d35 in independent experiments). Studies in 3T3-L1 adipocytes indicated the direct effects of RSV and NR on the DNA methylation machinery and favoring browning features. The results support epigenetic effects being involved in WAT programming by neonatal RSV or NR supplementation in male mice.
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Nüsken, Eva, Eva-Maria Turnwald, Gregor Fink, Jenny Voggel, Christopher Yosy, Tobias Kretschmer, Marion Handwerk, et al. "Maternal High Fat Diet and in-Utero Metformin Exposure Significantly Impact upon the Fetal Renal Proteome of Male Mice." Journal of Clinical Medicine 8, no. 5 (May 11, 2019): 663. http://dx.doi.org/10.3390/jcm8050663.
Повний текст джерелаАнотація:
There is accumulating evidence for fetal programming of later kidney disease by maternal obesity or associated conditions. We performed a hypothesis-generating study to identify potentially underlying mechanisms. Female mice were randomly split in two groups and fed either a standard diet (SD) or high fat diet (HFD) from weaning until mating and during pregnancy. Half of the dams from both groups were treated with metformin ((M), 380 mg/kg), resulting in four experimental groups (SD, SD-M, HFD, HFD-M). Caesarean section was performed on gestational day 18.5. Fetal kidney tissue was isolated from cryo-slices using laser microdissection methods and a proteomic screen was performed. For single proteins, a fold change ≥1.5 and q-value <0.05 were considered to be statistically significant. Interestingly, HFD versus SD had a larger effect on the proteome of fetal kidneys (56 proteins affected; interaction clusters shown for proteins concerning transcription/translation, mitochondrial processes, eicosanoid metabolism, H2S-synthesis and membrane remodeling) than metformin exposure in either SD (29 proteins affected; clusters shown for proteins involved in transcription/translation) or HFD (6 proteins affected; no cluster). By further analysis, ATP6V1G1, THY1, PRKCA and NDUFB3 were identified as the most promising candidates potentially mediating reprogramming effects of metformin in a maternal high fat diet.
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Bradley, Casey L., Thomas S. Shieh, Michael J. Azain, Tsung Cheng Cheng Tsai, Shelby Nosbisch, and Roger Walk. "PSV-14 The Efficacy of Feeding a Bioactive Peptide in Comparison to Narasin in Growing Pigs in a Commercial System on Growth Performance and Efficiency." Journal of Animal Science 99, Supplement_1 (May 1, 2021): 197. http://dx.doi.org/10.1093/jas/skab054.321.
Повний текст джерелаАнотація:
Abstract At 8-wk post-weaning, pens of split-sexed pigs (26.0 ± 0.25 pigs/pen; 31.3 ± 0.11 kg; DNA genetics) being housed in a commercial research unit were randomly assigned to one of two dietary treatments to compare the growth performance and efficiency of the system’s commercial nutritional program that included narasin (Skycis™, Elanco Animal Health, Greenfield, IN) at 13.6 g/tonne to a product (2 kg/tonne) containing a combination of bioactive peptides and enzymes (PEP; Peptiva® Optimo, Vitech Bio-Chem Corporation, Orange, CA). Dietary treatments were fed through 4 phases based on feed budgets. Pens were weighed bi-weekly through 59-d on test. There were 12 replications or pens per treatment. Feed was delivered and measured using a Feed Logic system and weigh backs were conducted utilizing a calibrated ruler. Average daily gain and feed intake were calculated on a pen basis. Data were analyzed as a mixed model with dietary treatment, gender, and treatment x gender interaction included. There were no interactions reported (P ≥ 0.0965). During the study pigs performed at or above their commercial counterparts. Overall, body weight, ADG, and ADFI were not impacted by treatment, but pigs fed PEP had an 2.1% improvement in feed efficiency compared to the narasin fed pigs. These results indicate that feeding bioactive peptides plus enzymes may improve feed efficiency without the need of an ionophore in the grower period in a commercial swine facility.
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Castell, A. G., and R. L. Cliplef. "Related responses in the live performance and carcass measurements of progeny from sows selected for thinner backfat." Canadian Journal of Animal Science 73, no. 3 (September 1, 1993): 471–82. http://dx.doi.org/10.4141/cjas93-052.
Повний текст джерелаАнотація:
Landrace-sired progeny (B-boars, G-gilts and CM-castrates) were obtained from sows in two Hampshire lines (Control, Select) derived by applying a selection index which had three times the emphasis on backfat reduction than on post-weaning growth to 90 kg. Experiment 1 used 72 pigs from the Generation 1 sows and a split-plot design with line as the main plot and sex-type as the sub-plot. A 16% CP diet was fed, ad libitum, in the 24 pens over the period from 26 to 100 kg liveweight. No significant (P < 0.05) differences in live performance or carcass measurements were found between pigs from the two lines. However, characteristic differences among the sex types were observed, e.g., the slower growth by G, higher intake by CM and superior gain:feed by B. Experiment 2, following the same format with Generation 5 progeny (N = 90 and 30 pens), revealed a difference (P < 0.01) in daily intake (ADI) relative to liveweight (LWT) between Control (ADI = 123 × LWT0.729; R2 = 0.89, P < 0.01) and Select (ADI = 123 × LWT0.716; R2 = 0.84, P < 0.01) pigs. The lack of significant differences for other live and carcass criteria could be explained if the index was favouring individuals with low appetites and reducing the potential for high rates of lean tissue deposition in the Select pigs. Growth of all the pigs from birth to market weight, examined by correlation and regression analyses, suggested that pre-test feeding practices were also limiting the attainment of maximum rates of lean tissue deposition. Key words: Pig, selection index, growth rate, carcass, appetite
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Ahola, L., J. Mononen, T. Pyykönen, and M. Miskala. "Group housing of farmed silver fox cubs." Animal Welfare 15, no. 1 (February 2006): 39–47. http://dx.doi.org/10.1017/s0962728600029924.
Повний текст джерелаАнотація:
AbstractIn the present study, the effects of social environment on the welfare of farmed silver fox cubs were clarified. After weaning, cubs from silver fox litters were housed (1) singly, (2) in litters until the end of September and thereafter singly, or (3) in litters throughout their growing season. Separating the cubs at the onset of the species' natural dispersal time may not be strictly beneficial for the cubs because it may limit the animals' possibilities to fulfil their needs for social behaviour. However, the lower incidence of bite wounds in both the single housed cubs and the cubs from litters that were split in autumn showed some beneficial effects of separating the cubs. The cubs that were group housed in litters for the whole time were focussed on their own social system, were more averse to human presence and showed greater responses to acute stress than the cubs that were single housed for at least part of the time. However, the serum cortisol level following adrenocorticotropic hormone administration suggested that cubs that were group housed in litters were less stressed over the long-term compared with the cubs that were single housed for at least part of the time; the low incidence of stereotypic behaviour in the cubs raised in litters also supports this hypothesis. Accordingly, and despite some unsolved questions regarding interpretation of the hypothalamic-pituitary-adrenal axis activity, the results from this present study show that social contacts were important for the welfare of silver fox cubs, and suggest that farmed silver fox cubs could possibly be raised in litters without jeopardising their welfare or deteriorating their fur quality.
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Croker, KP, RJ Lightfoot, TJ Johnson, NR Adams, and MJ Carrick. "The effect of selection for resistance to clover infertility on the reproductive performances of Merino ewes grazed on oestrogenic pastures." Australian Journal of Agricultural Research 40, no. 1 (1989): 165. http://dx.doi.org/10.1071/ar9890165.
Повний текст джерелаАнотація:
Rams were bred from ewes which had either maintained their fertility after grazing highly oestrogenic pastures for three to seven years. or, over the same period grazed �control� on or lowly oestrogenic pastures In 1977 and 1978 these rams were joined with a random selection of ewes, which had been grazed on lowly oestrogenic pastures, to produce contemporary Resistant and Control ewes.The Resistant and Control ewes were split at weaning into groups which subsequently were grazed on oestrogenic or non-oestrogenic pastures during each pasture growing season (May to October) of the experiment During the dry spring-summer period the ewes were regrouped and entire rams were joined with them for 42 days from early in January to determine whether resistance to the development of clover infertility had been inherited.The reproductive performances of the ewes were measured from two until eight years of age over the period from 1979 to 1986. In addition, the masculinization of the vulvas was monitored, mucus product ion was measured in the second last year, and the histology of the cervixes was observed when the experiment was terminated.The fertility of the Resistant ewes was affected by the oestrogenic pasture in the later years of the experiment, but the level of depression was significantly lower than that measured in the Control ewes grazed on oestrogenic pasture The realized 'heritability' of the ewes' fertile lifetime on oestrogenic pasture was estimated to be 0.73 with a standard error of 0.30.This resistance was associated with histological changes, which confirmed that the Resistant ewes were protected against oestrogen-induced damage. These results support the hypothesis that res istance to the development of clover infertility was present in these ewesA more intensive selection programme involving both ewes and rams may impart a higher level of resistance to ewes This would reduce the adverse effects of oestrogenic pastures on ewe flock productivity.
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Cabrera, Rafael A. "PSIII-16 The effect of Activo and a competitor phytogenic on growth performance and carcass characteristics of grow-finish pigs." Journal of Animal Science 97, Supplement_2 (July 2019): 172–73. http://dx.doi.org/10.1093/jas/skz122.305.
Повний текст джерелаАнотація:
Abstract The objective of this study was to evaluate the effects of feeding two phytogenics compunds on growth performance and carcass characteristics in grow-finish pigs. Activo is a phytogenic feed additive consisting of a blend of microencapsulated secondary plant compounds used as an alternative to antibniotics to support gut health and overall animal performance. The study was desgined as a split plot design with 2 treatments (Activo and Control) with 44 replicates each and 22 pigs per pen. Pigs were alloted by weight (41.9 kgs in average) and age (about 12 weeks of age). Three dietary feeding phases were used. Grow-finish phase 1 (9-16 weeks post weaning) containing 13.6 g/ton of Skycis plus the tested phytogenics; grow-finish phase 2 had the tested phytogenics and finally gorw-finish phase 3 had 6.75 g/ton of Ractopamine plus the tested phytogenics. There were no siginifcant differences between the two groups on overal growth performance and mortality. Carcass characteristics data was analyzed by combining harvest cuts 1 and 2. Cut 1 was performed 15 days after the supplementation of Ractopamine and cut 2 when the barn was empty. This includes 27 pens for the Activo group and 30 pens for the Control group due to carcass data that was removed or missing. Any pen with a harvest cut missing 3 or more carcasses was removed from the data set. The Acitvo group had heavier (P = 0.03) hot carcass weigh (101.7 vs. 100.3 kgs, respectively) and higher (P = 0.04) carcass yield % (76.3 vs. 75.8%, respectively) when compared to the Control group. There was a tendency for the Activo group to have higher (P = 0.06) Longissimus muscel depth than the Control group. In conclusion, the Activo group appears to be a better alternative to antibiotics than the competitor phytogenic.
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Kim, Bok Eum, Kang Ryul Min, Hyung Tack Kim, Hyung-Joon Ahn, and Seong Taek Kim. "Analysis of splint weaning in temporomandibular disorder patients." Journal of Dental Rehabilitation and Applied Science 37, no. 4 (December 31, 2021): 225–31. http://dx.doi.org/10.14368/jdras.2021.37.4.225.
Повний текст джерела
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Heo, J. M., J. C. Kim, C. F. Hansen, B. P. Mullan, D. J. Hampson, and J. R. Pluske. "Effects of dietary protein level and zinc oxide supplementation on performance responses and gastrointestinal tract characteristics in weaner pigs challenged with an enterotoxigenic strain of Escherichia coli." Animal Production Science 50, no. 9 (2010): 827. http://dx.doi.org/10.1071/an10058.
Повний текст джерелаАнотація:
The interactive effects of dietary protein level, zinc oxide (ZnO) supplementation and infection with an enterotoxigenic strain of Escherichia coli (ETEC) on performance responses and gastrointestinal tract characteristics were examined. Ninety-six individually housed, 21-day-old pigs (1 : 1 gender ratio) with initial bodyweight (BW) of 7.2 ± 0.69 kg, were used in a split plot experiment, with the whole plot being challenge or no challenge with ETEC and the dietary treatments used as subplots and arranged in a completely randomised 2 × 2 factorial design, with the factors being (i) two dietary protein levels (251 versus 192 g/kg crude protein) and (ii) addition or no addition of 2.5 g/kg ZnO. No antibiotic was added to the diet. The ETEC infection decreased average daily gain (P < 0.001) and increased feed conversion ratio (P < 0.01). Protein level had no effect on performance of pigs while ZnO supplementation increased (P < 0.001) average daily gain and average daily feed intake and hence decreased feed conversion ratio (P < 0.001). There were no 2- or 3-way interactions for growth performance indices (P > 0.05). Feeding a lower protein diet did not influence (P > 0.05) faecal volatile fatty acid concentrations. In non-infected pigs, feeding a lower protein diet caused a lower pH in the jejunum and ileum compared with pigs fed a higher protein diet (P < 0.05 and P < 0.01, respectively). However, feeding ZnO-supplemented diets increased (P < 0.05) the pH in the stomach and caecum compared with feeding diets without ZnO supplementation. Protein level did not alter (P > 0.05) empty BW but dietary supplementation with ZnO increased empty BW (P < 0.05). Neither protein level nor ZnO supplementation modified small intestinal morphology, although a tendency for an interaction (P < 0.1) was detected for jejunal villous height between protein level and ZnO supplementation. The results indicate that feeding ZnO-supplemented diets improved pig performance, and feeding a lower protein diet without ZnO supplementation did not compromise performance nor modify measures of gastrointestinal tract structure and function compared with pigs fed a diet higher in protein after weaning.
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Behrendt, R., A. J. van Burgel, A. Bailey, P. Barber, M. Curnow, D. J. Gordon, J. E. Hocking Edwards, C. M. Oldham, and A. N. Thompson. "On-farm paddock-scale comparisons across southern Australia confirm that increasing the nutrition of Merino ewes improves their production and the lifetime performance of their progeny." Animal Production Science 51, no. 9 (2011): 805. http://dx.doi.org/10.1071/an10183.
Повний текст джерелаАнотація:
Experiments conducted by Lifetimewool at plot-scale have shown that differences in the maternal liveweight during pregnancy and lactation (liveweight profiles) of individual Merino ewes influences their wool production and reproductive rate as well as the birthweight, survival, weaning weight and lifetime wool production of their lambs in a predictable manner. This study determined whether these impacts of nutrition of the ewe on ewe and progeny performance are measurable on commercial properties across southern Australia at a paddock-scale where ewes were aggregated into flocks with a greater spread of the date of conception and where the liveweight profile of the flocks were managed based on random samples of 100 ewes and liveweight was uncorrected for fleece weight or conceptus. Eighteen paddock-scale experiments at 15 sites were conducted in cooperation with wool producers across Victoria, Western Australia, New South Wales, South Australia, and Tasmania. Each co-operator joined up to 1000 mixed aged adult Merino ewes. The flock was scanned using ultrasound at Day 50 from the start of joining to identify those ewes that conceived during the first 21 days of joining. These ewes were then split at random into two treatments and fed to achieve a target difference in liveweight of 10 kg or ~1 condition score/fat score at lambing. The production of ewes during their year of pregnancy and following their next joining was measured as was the performance of their progeny up to their third shearing. Only the 13 paddock-scale experiments that achieved a difference in liveweight profile at lambing of at least 4 kg were included in the final analysis. In these 13 experiments, increasing the nutrition of Merino ewes during pregnancy clearly increased the clean fleece weight and fibre diameter in ewes and the survival and lifetime wool production of their lambs. In most cases the size of the effect was not significantly different to that predicted by the relationship derived using individual liveweight profiles in the plot-scale experiments. This confirms that managing average ewe liveweight or condition score/fat score profile through better nutrition will lead to predictable increases in the performance of ewes and their progeny performance under commercial conditions and validates the use of the plot-scale relationships in economic analyses.
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Vasudevan, Srikanth, Shriram Vaidya, Ritu Baath S., Ashok Basur C., Anantheswar Yellambalase N., and Sudarshan Reddy Nagireddy. "Temporary Extrathoracic Vacuum Therapy Splint in Chest Wall Reconstruction." Indian Journal of Plastic Surgery 54, no. 02 (April 2021): 211–14. http://dx.doi.org/10.1055/s-0041-1729502.
Повний текст джерелаАнотація:
Abstract Background Paradoxical respiration is a sinister consequence of bony chest cage defects which can persist even post chest wall reconstruction. It leads to prolonged dependence on mechanical ventilation postoperatively, thereby delaying recovery. Methods Negative pressure wound therapy (NPWT) was applied in early postoperative period to a patient with chest wall defect reconstructed with folded prolene mesh and free anterolateral thigh flap. Arterial blood gas (ABG), fraction of inspired oxygen (FiO2), peak end expiratory pressure (PEEP), oxygen saturation (SpO2), and blood pressure (BP) readings pre and post NPWT application were compared. Results There was marked improvement in the breathing mechanics and related parameters post NPWT application over the flap. Conclusions Negative extrathoracic pressure in the form of a temporary splint can enable early weaning off the ventilator and a smoother postoperative recovery in reconstructed chest wall defects.
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Wand, J. S. "The Natural History of Carpal Tunnel Syndrome in Lactation." Journal of the Royal Society of Medicine 82, no. 6 (June 1989): 349–50. http://dx.doi.org/10.1177/014107688908200612.
Повний текст джерелаАнотація:
In a retrospective postal study of 27 women who have developed carpal tunnel syndrome (CTS) in the puerperium, the condition was found to affect predominantly elderly primiparous women (mean age 31.5 years). The condition was associated with breastfeeding in 24 women. The three who did not breastfeed had less severe symptoms which resolved within one month of onset. The symptoms developed a mean of 3.5 weeks following delivery, lasted 6.5 months and started to resolve within 14 days of weaning. Symptomatic treatments with either splint-age, diuretics, non-steroidal anti-inflammatory drugs or steroid injections provided some benefit. Two patients required surgical decompression. All patients were symptom-free by one year.
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Levit, Shmuel, Naum Torban, Mona Boaz, Maria Weichman, Joseph Azuri, Yossi Manisterski, Eugene Merzon, et al. "Gravicentric approach to Type 2 Diabetes therapy. The success prediction. A proof-of-concept." Pharmacy Formulas 2, no. 2 (July 4, 2020): 48–60. http://dx.doi.org/10.17816/phf34728.
Повний текст джерелаАнотація:
This study is the proof-of-concept of our "Gravicentric" theory. This concept is based on several fundamental points: obesity as the main foe; rapid reversibility of the disease; as well as a new perspective on the roles different pharmacological classes play in general, and the role of insulin and GLP-1 analogs, in particular. The paper presents and discusses our experience of the implementation of insulin and GLP-1 analogs. The possibility of "insulin weaning"; the therapeutic approach for over-treated patients; and physiological dosing of insulin is also discussed therein.
Objectives
Primary: To evaluate the long-term efficacy of GLP-1 analogs in insulin-treated Type 2 Diabetes Mellitus (T2DM) patients.
Secondary: To analyze which patient would most likely benefit from this combined treatment.
Methods
In 54 T2DM patients with a mean disease duration of 17.5 years and a mean extent of insulin therapy of 4.5 years, additional GLP-1 analogs therapy was prescribed. Mean duration of GLP-1 treatment was 25.8 months (2.15 years).
During the intervention, clinical, biochemical, and anthropometric parameters were analyzed. Compliance, Hypoglycemia and Metabolic Index (MI) assessments were implemented.
Results
Mean Glycated hemoglobin (HbA1C) decreased from 9.28 1.43 to 8.54 1.4% on GLP-1 analogs, p 0.01. Total Daily dose of Insulin (TDI) showed considerable reduction: 80.6 42.7 U/day before starting GLP-1 vs.41.0 30.7 U/day on GLP-1, p 0.01. These changes were directly linked to weight loss: BMI has dropped from 35.1 4.8 kg/cm2 before, to 32.8 5.0 kg/cm2 on GLP-1 analogs, with patients losing 6.7 kg on average. Moreover, 13 (24%) participants discontinued at least one kind of insulin, while 7 (13%) stopped taking insulin completely, with simultaneous improvement in diabetes control. No clinically significant hypoglycemia was observed.
Post-hoc, the participants were categorized according to each patients ability to reduce TDI by more than 20 U/day, and then split into two groups. Group A 34 patients (64.2%) who successfully reduced TDI; Group B 19 patients (35.8%) who failed to do so. The comparison of the two groups showed the following:
Significantly larger virtually twice as large baseline TDI in Group A (97.440.4 U/day vs. 52.231.0 U/day), p 0.001.
Very effective BMI reduction (BMI 3.3 2.4 kg/cm2 0.9 1.2 kg/cm2, p 0.001) and much better compliance (1.4 1.1 vs. 2.2 1.0, p 0.02) in Group A.
A considerable decline of insulin requirements in group A, on GLP-1 therapy (TDI on GLP-1 was -62.4 31.9 U/day) with no TDI reduction in Group B (TDI on GLP-1 was +0.03 14.1 U/day, p 0.001).
Thus, in spite of the fact that on GLP1 therapy HbA1C has declined to the same levels in both groups, patients from group A became much leaner and metabolically healthier.
We suggest overtreatment as the critical factor of obesity in Group A.
Conclusions
Adding GLP-1 analogs to insulin in poorly controlled, insulin-treated T2DM patients resulted in an impressive weight (BMI) reduction with significant improvements in glucose control. This provided for a further decline in insulin resistance and insulin requirements. We suggest that the best candidate for successful GLP-1 analogs therapy is an obese, overtreated and compliant T2DM person. Changes in Metabolic Index (MI) rather than surrogate glycemic parameters (HbA1C) are better predictors of a successful T2DM therapy. Neither the duration of diabetes nor the length of insulin therapy in the past is likely to have a critical role in predicting success. These findings are proof-of-concept of our Gravicentric theory in T2DM.
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Tarnawsky, Stefan P., Mervin C. Yoder, and Rebecca J. Chan. "PTPN11D61Y/+; Vavcre+ Animals Commonly Succumb to Leukemia Relapse Despite Robust Engraftment of Transplanted Wild-Type Hematopoietic Stem and Progenitor Cells." Blood 128, no. 22 (December 2, 2016): 496. http://dx.doi.org/10.1182/blood.v128.22.496.496.
Повний текст джерелаАнотація:
Juvenile Myelomonocytic Leukemia (JMML) is a rare childhood myelodysplastic / myeloproliferative overlap disorder. JMML exhibits myeloid populations with mutations in Ras-Erk signaling genes, most commonly PTPN11, which confer growth hypersensitivity to GM-CSF. While allogeneic hematopoietic stem cell transplant (HSCT) is the treatment of choice for children with JMML, 50% of children succumb to leukemia relapse; however, the mechanism leading to this high relapse rate is unknown. We hypothesized that the hyperinflammatory nature of JMML may damage the bone marrow microenvironment, leading to poor engraftment of normal donor cells following transplant, permitting residual leukemia cells to outcompete the normal graft, and thus promoting leukemia relapse. Using Vav1 promoter-directed Cre, we generated a mouse model of JMML that conditionally expresses gain-of-function PTPN11D61Yin utero during development. While PTPN11D61Y/+; VavCre+embryos did not demonstrate in utero lethality, we observed a modest reduction of PTPN11D61Y/+; VavCre+ mice at the time of weaning compared to predicted Mendelian frequencies. Further, surviving PTPN11D61Y/+; VavCre+ mice developed elevated peripheral blood leukocytosis and monocytosis as early as 4 weeks of age compared to PTPN11+/+; VavCre+ controls. To address the hypothesis that an aberrant bone marrow microenvironment in the PTPN11D61Y/+ mice leads to poor engraftment of wild-type donor cells following transplant, we examined engraftment of wild-type hematopoietic stem and progenitor cells (HSPCs) in the PTPN11D61Y/+; VavCre+ mice and monitored animals for disease relapse. 16-24 week-old diseased PTPN11D61Y/+; VavCre+ and control PTPN11+/+; VavCre+ mice were lethally irradiated (11 Gy split dose) and transplanted with 5 x 105 CD45.1+ wild-type bone marrow low density mononuclear cells (LDMNCs), which simulates a limiting stem cell dose commonly available in a human HSCT setting. 6 weeks post-HSCT, PTPN11D61Y/+; VavCre+recipients demonstrated an unexpected elevated CD45.1+ donor cell contribution in peripheral blood compared to the control PTPN11+/+; VavCre+ recipients. However, despite superior engraftment in the PTPN11D61Y/+; VavCre+ recipients, these mice had a significantly shorter median survival post-HSCT due to a resurgence of recipient CD45.2-derived leukemic cells. We repeated the experiment using a high dose of CD45.1+ LDMNCs (10 x 106 cells) to determine if providing a saturating dose wild-type cells could prevent the relapse of recipient-derived leukemogenesis and normalize the survival of the PTPN11D61Y/+; VavCre+recipients. While this saturating dose of wild-type cells resulted in high peripheral blood chimerism in both the PTPN11D61Y/+; VavCre+ and PTPN11+/+; VavCre+ recipients, the PTPN11D61Y/+; VavCre+ animals nevertheless demonstrated significantly reduced overall survival. When we examined the cause of mortality in the HSCT-treated PTPN11D61Y/+; VavCre+mice, we found enlarged spleens, hypercellular bone marrow, and enlarged thymuses. Flow cytometry revealed that the majority of cells in the peripheral blood, bone marrow, and spleen were recipient-derived CD45.2+ CD4+ CD8+ T cells. To verify that the disease was neoplastic in origin, secondary transplants into CD45.1/.2 recipients were performed from two independent primary PTPN11D61Y/+; VavCre+and two independent primary PTPN11+/+; VavCre+ controls. Secondary recipients of bone marrow from PTPN11D61Y/+; VavCre+ animals rapidly succumbed to a CD45.2-derived T-cell acute lymphoid leukemia (T-ALL). Previous studies demonstrated that wild-type PTPN11 is needed to protect the integrity of the genome by regulating Polo-like kinase 1 (Plk1) during the mitosis of the cell cycle (Liu et al., PNAS, 2016). We now demonstrate that even when PTPN11 mutant animals are provided with saturating doses of wild-type HSCs, dysregulated residual recipient cells are able to produce relapsed disease. Collectively, these studies highlight the propensity of residual mutant PTPN11 cells to transform after being subjected to mutagenic agents that are commonly used for conditioning regimens prior to allogeneic HSCT. These findings suggest that modified pre-HSCT conditioning regimens bearing reduced mutagenicity while maintaining adequate cytoreductive efficacy may yield lower post-HSCT leukemia relapse in children with PTPN11mutations. Disclosures No relevant conflicts of interest to declare.