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1

Trottier, Nathalie Lucie. "Relationship between energy intake, backfat thickness and reproductive performance of sows". Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60421.

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Three experiments were conducted on sows. In experiment I, Landrace gilts were fed ad libitum, from 10 weeks of age to puberty, diets containing either 2800 (LE), 3400 (ME) and 3900 (HE) Kcal DE/kg. Age at puberty was delayed in gilts fed LE and ME. Backfat thickness was significantly reduced in LE and ME groups. Puberty onset was more determined by age and backfat thickness than by weight. In experiment II, all gilts that had shown normal heat within 240 days of age, were inseminated on the second estrus and given the same diet as received during their growing period. Feed was restricted to 2.0 kg per day during gestation and was provided ad libitum in lactation. Gilts in LE and ME gained less weight and backfat during gestation than gilts in HE group. Gilts gaining more weight and backfat during gestation, with a resulting higher body weight and backfat thickness at parturition, lost more in lactation. Incidence of anoestrus after weaning was higher in the LE and HE groups. In experiment III, multiparous Landrace-Yorkshire sows from two herds were used. An extended weaning to remating interval and reduced number of piglets weaned was observed in first and second parity sows. Lower reproductive performance in one herd was related to an excessive loss of backfat in lactation and a low backfat level at weaning.
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2

Williams, Amanda M. Lucy Matthew C. Safranski Timothy Jon. "Effects of heat stress on reproduction and productivity of primiparous sows and their piglets' performance". Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6460.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 23, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Drs. Matthew C. Lucy and Timothy J. Safranski. Vita. Includes bibliographical references.
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3

Oresanya, Temitope Frederick. "Effects of feeding flaxseed to sows during late gestation on lactation and litter performance". Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33434.

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A study was conducted to investigate the effect of supplemental fat from flaxseed (FL) on fatty acid (FA) profile, chemical composition, energy value of colostrum and milk, and litter performance. On day 107 of gestation a total of 59 large white sows were selected, blocked by parity and randomly allotted to one of three diets, 15% flaxseed (FL), 10% fullfat soybean (SB) or a control commercial (CO) diet containing corn and soybean meal. Diets were isocaloric and isonitrogenous but differed in fat content and FA composition. Colostrum and milk were collected soon after farrowing and on day 7, respectively, for fatty acid and chemical analysis. Dietary treatments did not affect sow feed consumption, weight loss, number of live pig born and weaned per litter. Similarly, pig birth weights, and day 7, 14, and 21 weights did not differ among treatment groups. FL significantly (p < 0.05) increased linolenic (LNA C18:3co3) and decreased palmitic (C16:0) and oleic (C18:1) acids in colostrum. FL also significantly (p < 0.001) increased LNA and arachidonic acid (C20:4) in milk, while it decreased myristic (C14:0), palmitic and palmitoleic (C16:1) acids. Chemical analysis showed no significant differences in total solids (TS) and energy value of colostrum while a significant (p < 0.05) increase in TS, fat concentration and energy value was observed in milk from FL. A total of 335 piglets were used in the plasma study of lipid metabolites. Triglyceride (TG), cholesterol, HDL cholesterol and glucose were not affected by dietary treatment (p > 0.05). Feeding FL to sows during late gestation and lactation enriches sow milk and piglets with LNA.
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4

Hultén, Fredrik. "Group-housing of lactating sows : effects on sow health, reproduction and litter performance /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1997. http://epsilon.slu.se/avh/1997/91-576-5424-7.gif.

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5

Hansen, Christiane. "The presence of follicular fluid in the porcine oviduct and its contribution to the acrosome reaction /". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61855.

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6

Booth, Paul James. "Physiological mechanisms mediating nutrition-reproduction interactions in the gilt". Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254056.

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7

Cao, Jiayin. "Copper nutrition in first-litter gilts". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68185.

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The effect of a low-Cu diet supplied to gilts during pregnancy and early lactation on dams and their offspring was obtained in seven pairs of first littermate gilts. They were housed in stainless steel metabolism cages in a controlled environment and fed semi-purified diets containing either 2.13 or 12.25 ppm Cu from 30 days of gestation through two weeks of lactation. Feed intake was restricted to 2 kg/day during pregnancy and 4 kg/day in the first two weeks of lactation. Reproductive performance of gilts was measured. Balance studies were conducted at 30, 60 and 100 days of gestation. Mineral levels in the plasma of gilts and piglets, and in colostrum and milk were determined. The low-Cu diet did not affect (p $>$ 0.05) weight changes during pregnancy. The duration of parturition was shorter for low-Cu than for control gilts (3.19h vs 5.71h, p 0.05). Low-Cu gilts had lower plasma Cu in early- and mid-gestation and farrowed piglets with lower plasma Cu and higher plasma Zn concentrations (p 0.05). Plasma Cu and Fe levels of newborn piglets were lower than those of their dams (p 0.05). Low-Cu gilts had lower Cu and higher Zn content in colostrum and also lower Cu in milk than control gilts (p 0.05). Colostrum was richer in Cu and Zn than milk (p 0.05). Higher dry matter digestibility was observed in low-Cu gilts during early gestation (p 0.05). Compared to control gilts, the low-Cu gilts tended to have higher Cu and Zn retention which was achieved by reduction of fecal Cu and Zn excretion. Utilization of minerals appeared to increase as pregnancy progressed.
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8

McNamara, Louise B. "Feeding and managing of the high performing sow in pregnancy and lactation, and growth and development of progeny". Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558977.

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9

Orzechowski, Kristina J. "Comparison of endocrine regulators of metabolism and postweaning reproduction in primiparous and multiparous sows". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ32205.pdf.

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10

Galvosaitė, Viktorija. "Sezono įtaka paršavedžių reprodukcijai". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080319_131257-83757.

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Abstract (sommario):
Apibendrinant literatūros apžvalgoje minėtus faktus yra aišku, jog mokslas įsiterpia į tiriamą problemą. Straipsnių, susijusių su reprodukcijos sutrikimų tyrimais, skaičius nuolat didėja. Galbūt dėl to, kad ES skiria daug dėmesio žemės ūkio plėtrai, galbūt konkurencingumas verčia ūkininkus nemažai lėšų skirti tyrimams, susietiems su reprodukcijos problemos išaiškinimu ir jos panaikinimu. Tyrimai atliekami visame pasaulyje, o atskirus rezultatus bandoma susisteminti, keliant įvairias hipotezes. Su ūkiu susijusios problemos sprendžiamos pasitelkiant architektus ūkio planavimui, oro ventiliavimo ir kondicionavimo, apšvietinimo bei kitus specialistus. Tačiau kaip stengiamasi išvengti problemų jų nuolat atsiranda. Iš išskirtų faktorių, įtakojančių paršavedės reprodukcinį pajėgumą, sezoniškumas yra bene svarbiausias elementas, o su juo susiję sutrikimai kelia nemažai diskusijų. Pagal gautus tyrimo rezultatus galime teigti, kad vasarą, esant aukštoms temperatūroms bei ilgam šviesos režimui, būtina keisti ūkinio pastato konstrukcijas, kad neužtrūktų kiaulaičių brendimo laikas. Sėkmingai reprodukcijos eigai keliami dideli reikalavimai: reikalingas kompetetingas personalas, aplinkos veiksnių kontrolė, dokumentavimas bei protokolavimias, atsakingumas ir kruopštumas. Apžvelgiant tyrimų rezultatus pagrindiniai paršavedės reprodukcinių savybių rodikliai žiemos sezono metu buvo geresni nei vasaros (vislumas 4,36 proc., pieningumas 7,7 proc., nujunkomo lizdo masė 8,57 proc. didesni)... [toliau žr. visą tekstą]
Summarizing the facts mentioned in the literature review it is obvious that science intervenes to the researched problem. The number of articles where the disorders of reproduction are researched is increasing. The reasons can be the big attention from EU to the development of agriculture, the fact that competitiveness makes the farmers to spend quite a lot of money on researches where the problems of reproduction are being explained and the ways to eliminate it are proposed. The researches are done all over the world and separate results are systemized, various hypotheses are being formed. Farm related problems are being solved with the help of architects to plan the farm, as well as the specialists of air ventilation and conditioning, illumination and other fields. But even if we try to avoid problems they occur. Among the highlighted factors influencing the reproduction capacities of sow, factor of seasons is almost the most important element, and the disorders related with it raise a lot of discussions. The light regime virtually doesn’t affect the reproduction capacities under the high temperature, so the heat stays the main reason of summer time infertility. Talking about the influence of seasons to the interval of weaning until the rutting it can be stated that in the optimal combination of air temperature and photoperiod, the reproduction capacities can be stimulated; however each factor separately can inhibit the reproduction. The results of this research shows that... [to full text]
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11

Saavedra, Aracelli Pinelli. "Vitamin E and vitamin C supplementation of sows in a hot environment : effects on reproductive performance, piglet tissue levels and aspects of immune status". Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369542.

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Summer and winter experiments were carried out to investigate the effects of dietary supplementation with vitamin E and vitamin C of sows in hot environments on reproductive performance, placenta transfer, piglet tissue vitamin E content and some indicators of immune status of sows and their litters. In summer, sows were given the following treatment diets: control, vitamin C 1g/day, vitamin C 10g/day, vitamin E 200 mg/kg feed, vitamin E 400 mg/kg fed, and combined vitamins (vitamin E 200 mg/kg feed + vitamin C 1 g/day). In winter, sows were given the following treatment diets: control, vitamin C 10g/day, vitamin E 500 mg/kg feed, combined vitamins (vitamin E 500 mg/kg/feed + vitamin C 10g/day). Data show that vitamin E had an effect on growth, but not on reproductive performance. Placental vitamin E concentrations were low but increased with dietary vitamin E supplementation. Vitamin E supplementation resulted in an increase in vitamin E content of sow plasma, piglet serum, colostrum and milk and piglet tissues. Supplementation with vitamin E and vitamin C had no consistent effect on parvovirus titer in sows. The relationship between sow plasma vitamin C and vitamin E concentrations and lymphocyte proliferation was not clear. Total Igs and IgG concentrations in piglet serum at weaning were significantly increased by the combined vitamin treatments. However, vitamins supplementation did not appear to have any effect in IgG colostrum. IgA concentration in milk was increased by the high level of vitamin E supplemented in the summer but not in the winter experiment.
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12

Karvelienė, Birutė. "Lytinio ciklo ir patologinės anoestrus būklės metu vykstantys pokyčiai sutrikusios reprodukcijos paršavedžių gimdoje". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20071129_145621-75225.

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Pirmą kartą buvo atlikti morfologiniai sutrikusios reprodukcijos paršavedžių endometriumo tyrimai, nustatyti endometriumo paviršinio ir liaukinio epitelio aukščio poky��iai, imuninių ląstelių infiltracija, PR-A ir ERα lokalizacija skirtingų lytinio ciklo stadijų ir patologinės anoestrus būklės metu. Nustatyta gonadotropinių hormonų (FSH, LH) poveikio įtaka progesterono (PR-A) ir estrogenų (ERα) receptorių kiekio ir lokalizacijos pokyčiams. Darbo tikslas: įvertinti įvairių veiksnių įtaką laikotarpio trukmei nuo paršelių atjunkymo iki paršavedžių rujos požymių pasireiškimo ir nustatyti morfologinius pakitimus bei estrogenų receptorių alfa (ERα) ir progesterono receptorių A (PR-A) pasiskirstymą sutrikusios reprodukcijos paršavedžių gimdoje lytinio ciklo ir patologinės anoestrus būklės metu.
Aim of the research: The aim of this research was to evaluate the effect of various factors on the duration of the period from piglets weaning to oestrus manifestation and to define morphological changes and distribution of estrogen receptors (ERα) and progesterone receptors A (PR-A) in the uterus of sows with disturbed reproduction during the oestrus cycle and pathological anoestrus condition. Novelty of the research: Morphological investigations of sows with disturbed reproduction endometrium were carried out for the first time, changes of luminar endometrial epithelium and glandular epithelium height, infiltration of the immune cells, PR-A and ERα localization during different stages of oestrus cycle and pathological anoestrus condition were studied. The effect of the number of gonadotropic hormones (FSH, LH), progesterone (PR-A) and estrogen (ERα) receptors and localization changes was studied.
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13

Simões, Vasco Jorge Gaspar. "Variations in the vulvar temperature of sows as determined by infrared thermography and its relation to ovulation". Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4822.

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Dissertação de Mestrado Integrado em Medicina Veterinária
The productive results of a pig’s herd are closely related to the reproductive performance of their animals. Although in the last years several techniques were implemented to improve the reproductive efficiency of pig production, such as artificial insemination (AI) and estrus synchronization, the prediction of ovulation continues to be made with some degree of uncertainty due to the lack of an accurate, practical and fast technique. In this experimental study, we tested the applicability of infrared thermography (IRT) for ovulation prediction, based on the variations observed in the vulvar skin temperature (VST) during the proestrus and estrus period. The group tested was composed by 36 crossbred Large White x Landrace females, of which 6 gilts and 30 multiparous sows. Estrus detection was performed twice daily in the morning and afternoon, starting one day after weaning (day 1). Temperature measurements were performed every 6 hours at 0000h, 0600h, 1200h and 1800h, from day 1 to day 7. Temperature was obtained from the vulvar area and from two marked spots in the gluteal area (GST), which worked as a control. A third variable (VGT) was obtained from the differential temperature between VST and GST. Ovary ultrasonography was performed in days 5 and 6, in order to detect ovulation; however, the exams were inconclusive and so a theoretical diagnosis of ovulation had to be established based on the weaning-to-estrus interval and the duration of estrus. The statistical analysis focused mainly in the VGT of two sub-groups of animals, starting estrus at days 4 and 5. The VGT increased progressively during the proestrus (p = 0.003 and p=0.017), reaching a peak 61 ± 10.8 h and 82 ± 6.6 h before expected time of ovulation (eOv) in group D4 and D5, respectively. After this point, it decreased significantly (p = 0.002), reaching a lowest point 25 ± 10.8 h and 28 ± 6.6 h before eOv. Although the occurrence of ovulation could not be determined but only estimated, we believe the variations found in the VGT reflect the variations in the estradiol blood levels that will, indirectly, lead to the occurrence of ovulation. Even if no statistical relationship between vulvar temperature and ovulation could be established, the results suggest that these temperature variations may be indirectly related to the occurrence of ovulation.
RESUMO - VARIAÇÕES NA TEMPERATURA VULVAR EM PORCAS DETERMINADAS POR TERMOGRAFIA DE INFRAVERMELHOS E A SUA RELAÇÃO COM OVULAÇÃO - Os resultados produtivos de uma exploração de suínos estão intimamente relacionados com o desempenho reprodutivo dos seus animais. Apesar de nos últimos anos várias técnicas terem sido implementadas com vista a melhorar a eficiência deste sector, como inseminação artificial e sincronização do estro, prever a ocorrência de ovulação continua a envolver um certo grau de incerteza, dada a inexistência de uma técnica precisa, prática e rápida. Neste estudo experimental foi testada a aplicabilidade da termografia de infravermelhos (IRT) para predição da ovulação, tendo por base as variações de temperatura registadas ao nível da região vulvar (VST) ao longo do pró-estro e estro. O grupo-teste era composto por 36 porcas cruzadas Large White x Landrace, das quais 6 eram marrãs e 30 porcas multíparas. A detecção do estro iniciou-se 1 dia após o desmame (dia 1), sendo realizada duas vezes por dia, de manhã e à tarde. As medições de temperatura foram realizadas a intervalos de 6 horas, às 0000h, 0600h, 1200h e 1800h, entre o dia 1 e dia 7. Foi avaliada a temperatura vulvar e de 2 pontos marcados na região gluteal (GST) que desempenharam o papel de controlos. Uma terceira variável (VGT) foi obtida a partir do diferencial de temperatura entre a VST e GST. Com vista a detectar a ovulação, foram realizadas ecografias aos ovários durante os dias 5 e 6; no entanto, os resultados foram inconclusivos, pelo que a ocorrência de ovulação foi estimada a partir do intervalo desmame-estro e duração do estro. A análise estatística centrou-se sobretudo na variável VGT de dois sub-grupos, compreendendo animais com início de estro no dia 4 e dia 5. A VGT aumentou durante o pró-estro (p=0.003 e p=0.017 para os grupos D4 e D5), atingindo um pico 61 ± 10.8 h and 82 ± 6.6 h antes da ocorrência estimada de ovulação (eOv). De seguida, diminuiu significativamente (p=0.002), atingindo um valor mínimo 25 ± 10.8 h e 28 ± 6.6 h antes da ocorrência estimada da ovulação. Ainda que a ovulação não possa ter sido determinada com rigor, entendemos que as variações observadas na VGT reflectem as variações nos níveis sanguíneos de estradiol que, indirectamente, vão levar à ovulação. Assim, apesar não ter sido demonstrada uma relação inequívoca, os nossos resultados apontam para uma possível relação indirecta entre as variações de temperatura vulvar e a ovulação.
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14

Harper, Allen F. "An assessment of the effects of dietary folic acid supplementation on serum folates status, conceptus development and reproductive performance in gilts and sows". Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/39434.

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The effects of dietary folic acid supplementation on serum folate status, conceptus development and reproductive performance in gilts and sows was investigated in a series of experiments. The specific objectives of the study were to: 1) to study the serum folates profile following rapid consumption of a single meal containing different levels of supplemental folic acid; 2) to study the effects of maternal folic acid supplementation on conceptus survival, growth and development prior to mid-gestation in gilts and sows; and 3) to study the effects of multiple levels of dietary folic acid supplementation on sow reproductive performance over four successive parities. In the first experiment (Chapter III), gilts fed a single, rapidly consumed meal, had a rapid increase in serum folates concentration during the first hour postprandial. Within eight hours after feeding, serum folates in the gilts had returned to near prefeeding levels. The results also suggest that supplementing the diet with increasing levels of folic acid over a range of 0 to 4 ppm results in more rapid postprandial uptake and elimination of folic acid from general circulation. In the second experiment (Chapter IV), supplementing the diet of first parity and third parity breeding sows with 2 ppm folic acid had no effect on litter size at day 45 of gestation. However, several measurements associated with placental and fetal growth were increased with folic acid supplementation. Results of a fifth parity trial with four levels of supplemental folic acid were variable and inconclusive. The implications of increased placental and fetal growth up to day 45 of gestation in the first and third parity sows is discussed. In the third experiment (Chapter V), a decline in serum folate concentration in pregnant sows from mating to mid- to late gestation was clearly demonstrated. Supplementing the sow's diet with folic acid over a range of 0 to 4 ppm resulted in a linear increase in serum folate concentration at mating, during gestation and at weaning. However, under the conditions of this experiment, folic acid supplementation had no significant effect on sow reproductive performance.
Ph. D.
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15

Nyström, Per-Erik. "Quantitative trait loci in pig production /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5712-2.pdf.

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16

Brandt, Ylva. "The effect of ACTH during oestrus on the reproduction in the sow : with special reference to duration of oestrus, ovulation, hormonal patterns, gametes and early embryo development /". Uppsala : Department of Clinical Sciences, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200614.pdf.

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17

Peters, James C. "Evaluating the efficacy of dietary organic and inorganic trace minerals in reproducing female pigs on reproductive performance and body mineral composition". Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141661190.

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18

Sterning, Marie. "Reproductive performance and oestrous symptoms in primiparous sows /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1996. http://epsilon.slu.se/avh/1996/91-576-5229-5.gif.

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19

Tantasuparuk, Wichai. "Sow reproductive performance in Thailand : effects of climate, breed, parity, lactation length, weight loss during lactation and weaning-to-service interval /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5938-9.pdf.

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20

Ilsley, Siân Elizabeth. "Plant extracts as dietary supplements for reproductive sows and piglets". Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411302.

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21

Mickevičienė, Inga. "Reprodukcinių savybių indekso kitimas priklausomai nuo paršavedžių amžiaus". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090507_100400-78811.

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Abstract (sommario):
Darbo tikslas: įvertinti paršavedžių reprodukcinių savybių indekso (R) kitimą didėjant paršavedžių amžiui. Darbo uždaviniai: 1. įvertinti tiriamųjų paršavedžių reprodukcinių savybių rodiklių kitimą nuo pirmo iki paskutinio apsiparšiavimo; 2. paskaičiuoti reprodukcinių savybių indeksus (R) kiekvienai paršavedei, atskirai kiekvienam apsiparšiavimui; 3. įvertinti reprodukcinių savybių indekso (R) kitimą didėjant apsiparšiavimų skaičiui.
Work goal: the analysis of change of an index of reproductive characteristics of a sow depending on age. For achievement of this goal, raise the following objektives: 1) to estimate change of reproductive characteristics of investigated sows from the first to the last farrows; 2) to calculate indexes (R) reproductive characteristics for each sow, separately on everyone farrow; 3) to estimate index change (R) reproductive characteristics at number increase farrow. The work has been executed in 2008 in the enterprise of pigs of the Kaunas area. It was made 14 groups of sows of breed landrace. Test sows were from first to seventh farrows. The analysis of a reproduction and calculations of an index of a reproduction are executed on everyone farrow (from 1 to 7). For an estimation of efficiency and a reproduction index were analyzed the following indicators: 1. Fertility of sows, in units; 2. Quantity of piglets 21 days old, in units; 3. Weight of nest of piglets 21 days old, in kilo; 4. Quantity of piglets at weaning, in units; 5. Weight of nest of piglets at weaning, in kilo. The analysis of the sow's fertility changes, depending on the quantity of farrows, found that the fertility increased from the first farrow. The lowest fertility was at first pigs sow – 9.93 piglets, the highest fertility was found during the fourth farrow – 10.63 units or 0.70 piglets more that the first farrow. From the fourth farrow was found the tendency of reduction of fertility, i.e. fertility of the... [to full text]
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22

Kim, Hyung-Joo. "Genetic parameters for productive and reproductive traits of sows in multiplier farms". Doctoral thesis, [S.l.] : [s.n.], 2001. http://webdoc.sub.gwdg.de/diss/2001/kim/kim.pdf.

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23

Chokoe, TC, e FK Siebrits. "Effects of season and regulated photoperiod on the reproductive performance of sows". South African Society for Animal Science, 2009. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001684.

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Abstract Reproductive performance of experimental commercial Dalland sows (n = 87) maintained under a constant photoperiod (10 h light and 14 h darkness) and control sows (n = 187) maintained under natural daylight length (10.4 h light in winter and 13.4 h light in summer) were compared. In early summer 4.1% of experimental sows returned to oestrus compared to 20.8% of the control sows. In late summer 9.1% of experimental sows returned to oestrus compared to 21.9% of the control sows. Reduced photoperiod improved the farrowing rate of experimental sows in the early summer breeding compared to the control group (95.4% and 81.3%, respectively). With winter breeding there was a small proportion of sows that returned to service in both groups (7.9% and 8.9%) while the farrowing rate was high in both groups (93.9% and 91.0% in the experimental and control groups, respectively). Litter sizes derived from early summer services were 11.4 and 11.6 for the experimental and control groups, respectively, while winter services led to litter sizes of 11.6 and 12.4 whereas in late summer services, regulated photoperiod had improved the litter size of the experimental group (12.3) compared to the control group (11.2).
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24

Misdariis, Nicolas. "Synthèse - Reproduction - Perception des Sons Instrumentaux et Environnementaux : Application au Design Sonore". Thesis, Paris, CNAM, 2014. http://www.theses.fr/2015CNAM0955/document.

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Ce mémoire présente une composition d’études et de travaux de recherche orientés autour de trois grandes thématiques : la synthèse, la reproduction et la perception des sons, en considérant à la fois les sons de nature musicale mais aussi environnementale. Il vise en outre un champ d’application, le design sonore, qui implique globalement la création intentionnelle de sons du quotidien. La structure du document est conçu selon un schéma relativement uniforme et comporte, pour chaque partie, une présentation générale de la thématique apportant des éléments théoriques et des données relatives à l’état de l’art, suivie de développements spécifiques permettant de converger vers les sujets d’étude propres à chaque thème – explicitement, formalisme modal dans la synthèse par modélisation physique, pour la partie "Synthèse" ; mesure et contrôle de la directivité des instruments de musique, pour la partie "Reproduction" ; timbre et identification des sources sonores, pour la partie "Perception"– puis d’une présentation détaillée des travaux personnels relatifs à chacun des sujets, le cas échéant, sous la forme d’un article publié. Ces divers éléments de connaissance et d’expérience propose donc une contribution personnelle et originale, volontairement inscrite dans un cadre de recherche élargi, pluridisciplinaire et appliqué
This dissertation presents a composition of studies and research works articulated around three main topics : synthesis, reproduction and perception of sounds, considering both musical and environmental sounds. Moreover, it focuses on an application field, the sound design, that globally involves the conception of intentional everyday sounds. The document is based on a rather uniform structure and contains, for each part, a general presentation of the topic which brings theoretical elements together with an overview of the state-of-the-art, followed by more precise developments in order to focus on the specific matters related to each topic – in detail, modal formalism in sound synthesis by physical modeling, for the "Synthesis" section ; measurement and control of musical instruments directivity, for the "Reproduction" section ; timbre and sound sources identification, for the "Perception" section – and then followed by a detailed presentation of the personal works related to each matter, in some cases, in the form of published papers. Then, these several elements of knowledge and experience offer a personal and original contribution, deliberately put in a broad, multidisciplinary and applied framework
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25

Rioux, Yann. "I[indice K1] et l'inhibition métabolique : hétérogénéité dans la réponse des cellules sous-endocardiques et sous-épicardiques?" Sherbrooke : Université de Sherbrooke, 1997.

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26

Orrett, Christopher Mark. "Quantitative genetic and genomic analyses of the effect of Porcine Reproductive and Respiratory Syndrome (PRRS) outbreaks on the reproductive performance of sows". Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31281.

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Porcine Reproductive and Respiratory Syndrome (PRRS) is, globally, one of the costliest of diseases to the pig industry. Despite enormous efforts, methods such as vaccination strategies and herd management have failed to fully control the disease. Exploiting the genetic variation in host response could be included as part of a multifaceted approach to mitigate the devastating impact of this disease. Establishing the presence of genetic variation and its underlying genetic architecture are key to implementing genomic selection, which is considered a viable and safe long-term disease control strategy. This thesis explores the effect of natural PRRSV outbreaks on the reproductive performance of sows, and the underlying genetic influences on it. Litter records were available from two farms, where Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) outbreaks had been confirmed using ELISA. One farm had full pedigree information, but for both farms 60K SNP genotypes were available. In both farms, performance records could be partitioned into an epidemic and non-epidemic phase using a previously established threshold method. The partitioning also identified a period of high reproductive failure not coinciding with a diagnosed PRRSV outbreak on one farm. This period was isolated and analysed separately. Linear mixed models were used to explore both genetic and non-genetic factors contributing to differences in reproductive performance associated with the two phases. This analysis identified five disease indicator traits identified showing significant differences (>95% CI) in least squares means between the epidemic and non-epidemic phase. These were the number of mummified, stillborn, dead and alive piglets per litter and the fraction of the total born dead. Alternative statistical models that accounted for differences in the severity of the individual PRRSV outbreaks were also considered throughout. Despite differences in the estimates associated with different models and farms, in general very low heritability estimates were obtained for these disease indicator traits during the non-epidemic phase, whereas the traits were found moderately heritable during the epidemic phase. Two genome wide association analyses methods were used to explore the distribution of the genetic effects throughout the genome: Family-based Score Test for Association (FASTA) and Genome-wide Rapid Analysis using Mixed Model and Regression (GRAMMAR). In addition, regional associations were studied using Regional Heritability Mapping (RHM). Associations were then further characterised using Measured Genotype (MG) analyses. Genome-wide significant associations were identified for five SNPs and one region. The regional association spans the region previously identified in an experimental challenge experiment of growing pigs, in association with viral load and weight gain. Different patterns of linkage disequilibrium (LD) are observed which may explain why this study and others failed to find single SNP effects at this location. One genome wide significant SNP on SSC15 was found between two previously identified SNPs associated with PRRSV mortality. Five further putative SNP associations are indicated by RHM and subsequent measured genotype analysis, two of which flank previously reported associations and indicate an epistatic effect, observed in several traits. In summary, this study showed that reproductive performance of sow is considerably reduced during PRRSV outbreaks and the genetics of the sow significantly affects variance in survival and mortality. Several novel genomic regions associated with the reproductive performance of sows in the absence and during PRRSV outbreaks have been identified in this study. In addition to these, the results suggest the region on SSC4 previously associated with PRRSV viral load and weight gain may also affect foetal mortality. These results demonstrate the potential for genomic selection to be used to mitigate PRRSV related reproductive losses, the greatest financial exposure faced by the pig industry. In addition, RHM is directly shown to capture genetic variance, where single SNP methods fail to identify an effect, highlighting the usefulness of this tool as a method to identify genomic regions with significant effect on production traits.
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27

Zak, Louisa Jane. "Physiological mechanisms mediating nutrition-reproduction interactions in the lactating and weaned primiparous sow". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21660.pdf.

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28

Brassard, Francis. "Développement d'un simulateur reproduisant le profil des routes sous les roues d'un vélo". Mémoire, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/1568.

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L'industrie du vélo utilise à profusion le terme confort sans savoir parfaitement ce que cela représente. Aucun outil scientifique n'existe afin d'identifier le confort et ainsi la conception d'un simulateur de vibration de la route est envisagée. Le principal objectif de ce projet de maîtrise est de concevoir un simulateur permettant de reproduire le profil de la route afin de retrouver les mêmes niveaux de vibration que lorsque le vélo roule sur la route. Ainsi, la conception du simulateur se divise en deux parties : la conception mécanique du banc de test qui sert de pièce maîtresse du simulateur ainsi que le calcul des profils numériques des routes. Le premier volet présente la conception mécanique du banc de test. Le banc de test est la pièce maîtresse qui supporte le vélo et qui transmet le mouvement provenant des actionneurs à l'aide d'un bras d'amplification mécanique des mouvements. Le mouvement est créé par des actionneurs de la compagnie D-Box qui présentent plusieurs limitations et contraintes influençant directement la conception du banc de test et le calcul des profils de route. La démarche afin de calculer des profils numériques des routes est présentée dans le deuxième volet. Les profils de route sont la représentation numérique de la route réelle. Ces derniers servent de signal alimentant les actionneurs du banc de test. Afin de calculer les profils, il est nécessaire de faire des mesures d'accélération sur la route et, à l'aide de la technique du problème inverse, les profils de route sont calculés. La démarche de conception se termine avec une validation du simulateur. Ce chapitre dédié à la validation démontre que l'utilisation d'une amplification mécanique à l'aide d'un bras de levier n'influence pas les mesures. La précision de la reproduction de la route est également étudiée alors qu'un écart de 6% à 9% est remarqué entre les mesures d'accélération sur la route et celles sur le banc de test. Le dernier volet du mémoire présente un exemple d'utilisation possible du banc de test. Une étude comparative identifie qu'il n'est pas suggéré d'utiliser des masses inertes afin de remplacer un cycliste. Ces résultats sont basés sur des études dynamiques d'un cadre de vélo.
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29

Funk, Nadine. "Reproductive performance of sows supplemented with an oil high in essential fatty acids during early gestation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0011/MQ53156.pdf.

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30

Langlois, Lise. "Reproduction sociale à l'Île d'Orléans stratégies, transmission du patrimoine et migrations sous le régime français". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq21783.pdf.

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31

Langlois, Lise. "Reproduction sociale à l'Île d'Orléans : stratégies, transmission du patrimoine et migrations sous le régime français". Sherbrooke : Université de Sherbrooke, 1997.

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32

Mazerolle, Marc J. "Mouvements et reproduction des amphibiens en tourbières perturbées". Thesis, Université Laval, 2004. http://www.theses.ulaval.ca/2004/21842/21842.pdf.

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Les déclins de populations d’amphibiens ont généré de nombreux travaux sur les effets de la perte d’habitats variés, mais peu en milieux naturellement acides. Néanmoins, plusieurs tourbières du sud-est canadien sont perturbées par l’extraction de la tourbe. Dans le premier chapitre, j’ai comparé l’utilisation des milieux tourbeux par les amphibiens à celle des milieux non tourbeux. Dans les quatre chapitres subséquents, j’ai quantifié les effets de l’extraction de la tourbe sur l’utilisation des étangs de tourbières par les amphibiens et mesuré les contraintes liées à leurs déplacements sur des surfaces exploitées. Les résultats indiquent que les amphibiens utilisent les tourbières surtout comme sites d’estivage. De plus, l’intensité de l’exploitation influence la fréquentation des étangs, mais la quantité et la proximité d’habitats complémentaires (i.e., étangs adjacents, forêt) semblent réduire ces effets. Finalement, les surfaces arides associées à certaines activités anthropiques telles que l’exploitation des tourbières ou l’agriculture, entravent les déplacements des grenouilles, bien que ces effets puissent être atténués par la présence de canaux de drainage.
Global amphibian population declines have generated numerous studies on the effects of habitat loss, but few have been conducted in naturally-acidic environments. Nevertheless, many peatlands are undergoing peat extraction in southeastern Canada. Through five chapters, I have studied the use of bog habitats by amphibians, quantified the effects of peat extraction on amphibian occurrence at bog ponds, and measured the constraints associated with movements over mined surfaces. Bogs were less productive breeding sites than less acidic upland sites, but were used by adults and juveniles following breeding outside bogs. Bog ponds on surfaces actively mined for peat offered suboptimal habitats to green frogs (Rana clamitans), whereas bog ponds on surfaces drained for future peat mining, characterized by the presence of drainage ditches and vegetation, provided supplementary frog habitat. However, this positive effect was only temporary, as these surfaces were to be eventually mined. In a study conducted at a larger scale and focusing on bog ponds on unmined surfaces, I showed the importance of the amount and proximity of complementary habitats (i.e., adjacent ponds, forest) on the spatial distribution of amphibian presence at ponds. Moreover, frog movement experiments revealed that frogs translocated on barren peat surfaces had a lower probability of homing successfully than those translocated at a similar distance on an undisturbed surface, and that dehydration risks were the lowest on natural surfaces with vegetation cover. No reproduction occurred in drainage ditches, although frog survival in these structures was high. In addition, ditches did not impede the movements of individuals. Globally, results indicate that amphibians use bogs mostly as summering sites. Furthermore, peat mining intensity influences the occurrence of amphibians at ponds, but the proximity and amount of complementary habitats could mitigate these effects. Finally, barren surfaces associated with certain human disturbances such as peat mining and agriculture impede frog movements, although drainage ditches, particularly those containing water, may facilitate movements across these hostile environments.
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33

Tate, Evan. "A Comparison of Pregnant Mare Serum Gonadotropin and P.G. 600® to Improve Reproductive Efficiency in Sows". TopSCHOLAR®, 2007. http://digitalcommons.wku.edu/theses/382.

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Three hundred and nineteen sows were utilized to study the effects of pregnant mare serum and P.G 600 on reproductive efficiency. Sows were randomly allotted to treatments. Sows were evaluated for age (# of parities), breed composition and body condition score. Three sows who shared all three fields in common were randomly treated with one of three treatments the morning after weaning: 1. (S) Controls: 5ml of Sterile Saline Solution 0.9% 2. (M) Treatment (PMSG): 12ml of Pregnant Mare Serum 3. (P) Treatment (PG600)® 5ml of P.G. 600 (Intervet America Inc., Millsboro, DE) No differences were observed for total number of pigs born among treatments (P>.05). Neither parity, body condition or breed composition had a significant influence on total number born. However, treatments of pregnant mare serum and P.G. 600 to controls resulted in significantly shorter wean to estrus intervals (P<.0002 vs. P<.0001) than sows in the control group respectively) from weaning to estrus. Additionally, P.G. 600 treated sows had shorter weaning to estrus intervals than PMSG treated sows (P<.0802).
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34

Gourdine, Jean-Luc Bertrand. "Analyse des facteurs limitant les performances de reproduction des truies élevées sous un milieu tropical humide". Phd thesis, INAPG (AgroParisTech), 2006. http://pastel.archives-ouvertes.fr/pastel-00002320.

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Les régions tropicales sont caractérisées par des contraintes climatiques importantes pour la production porcine pouvant induire une diminution des performances des animaux et du revenu de l'éleveur. Lorsque la température dépasse 22°C, la truie allaitante se trouve en situation de stress thermique. Elle réduit alors son ingestion d'aliment, ce qui généralement a des conséquences négatives sur ses performances de lactation et ses performances ultérieures de reproduction. Cependant, la plupart des travaux disponibles ont été réalisés en milieu tempéré avec des conditions difficilement transposables à celles rencontrées en milieu tropical humide. Les objectifs du travail de thèse sont de déterminer et de caractériser les facteurs qui affectent les performances de lactation et de reproduction des truies élevées sous un climat tropical humide. Une attention particulière a été portée sur les effets du rang de portée, du type génétique et de leurs interactions respectives avec la saison. A partir des données climatiques mesurées à proximité de l'élevage, deux saisons ont été déterminées: une saison fraîche et une saison chaude. L'hygrométrie moyenne étant comparable (i.e., environ 83%) d'une saison à l'autre, les deux saisons sont discriminées principalement par le niveau de température ambiante (23,7°C en saison fraîche et 26,0°C en saison chaude). Dans notre étude, les performances des truies ont été mesurées pendant 5 années sur deux races "extrêmes", une race dite "conventionnelle", la truie Large White (LW), et la race locale caribéenne, la truie Créole (CR). A partir de la base de données constituée, nous avons dans un premier temps étudié les effets de la saison et du rang de portée sur les performances de lactation de 106 truies LW (301 lactations). Une 2ème expérience nous a permis de prendre en considération les effets du type génétique de la truie (30 CR et 41 LW sur un total de 179 lactations) sur les performances et le comportement alimentaire en lactation. Dans une 3ème expérience, les effets du climat tropical sur les performances de reproduction ont été étudié sur 255 truies LW (1 181 saillies). Enfin, une 4ème étude a porté sur les facteurs affectant la température rectale (TR) des truies en lactation (222 lactations de 43 CR et 42 LW). Les performances des truies en lactation sont plus faibles en saison chaude qu'en saison fraîche: la consommation d'aliment des truies et la croissance de la portée sont fortement réduites et le niveau de réserves corporelles mobilisées augmente en saison chaude. La TR des truies allaitantes est plus élevée en saison chaude qu'en saison fraîche (38,9 vs. 38,6°C) et plus faible chez les multipares que chez les primipares (38,7 vs. 38,9°C). La truie CR se caractérise par un plus faible poids et une plus grande adiposité (-70 kg et + 20 mm d'épaisseur de lard à la mise bas) que la LW. Elle consomme moins d'aliment que la LW (3,4 vs. 4,8 kg/j) en relation à sa faible vitesse d'ingestion (80 vs 150 g/min). Cela se traduit par une réduction de la taille des repas des CR (390 vs. 550 g/repas), alors que le nombre de repas est semblable entre types génétiques (9,0 repas/j). La baisse d'appétit en saison chaude est plus prononcée chez les truies LW multipares que chez les primipares (-1,0 vs. -0,4 kg/j) et chez les truies LW que chez les CR (-1,0 vs. -0,5 kg/j). Les performances de reproduction mesurées après le sevrage des truies sont plus faibles en saison chaude, en particulier chez les primipares. L'intervalle sevrage-oestrus et l'intervalle sevrage saillie fécondante des truies augmentent en saison chaude, et le taux de conception est réduit pendant cette période de l'année. Les performances de reproduction des truies CR sont moins affectées par la saison, ce qui indique qu'elles pourraient mieux tolérer la chaleur. Ce résultat est conforté par une moindre augmentation de la TR en saison chaude chez les CR que les LW (+ 0,2 vs. +0,4°C). En conclusion, nos résultats contribuent de manière significative à la caractérisation des performances des truies élevées en milieu tropical humide. Dans nos conditions expérimentales, il existe une forte variabilité interindividuelle de la réponse des truies au stress thermique, dont une partie non négligeable semble être d'origine génétique (résultats préliminaires). Il semble y avoir beaucoup à espérer de programmes de sélection intégrant des critères d'adaptation aux températures élevées pour l'amélioration de la production porcine en régions tropicales humides
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35

Fortier, Marie-Ève. "Influence du sélénium, sous forme organique et inorganique, sur les performances de reproduction des truies prépubères". Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25623/25623.pdf.

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36

Muller, Tracy Louise. "Changes in sow body composition during lactation and their impacts on litter performance and sow reproductive success". Thesis, Muller, Tracy Louise (2021) Changes in sow body composition during lactation and their impacts on litter performance and sow reproductive success. PhD thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/64107/.

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During lactation, sows undergo increased metabolic demand whereby tissue mobilisation may be required to support litter growth. Excessive lactational catabolism can subsequently impact litter performance and the sows’ ability to rebreed. Current on-farm methods to measure sow body condition are subjective and/or lack the ability to capture a change in muscle mass perhaps of more importance in the leaner sow. Advances are required in the practical measurement of sow body composition with an understanding of how management of sows in response to these measurements can improve overall productivity and efficiency of the herd. The core objectives of the current thesis were to a) develop a practical method for the measurement of sow body composition, b) investigate the impact a change in body composition during lactation has on litter performance and subsequent reproduction status, and c) examine lactational dietary energy and lysine requirements using a two stage feeding program to minimise changes in sow body composition without negatively impacting litter growth or subsequent reproductive success. A series of experiments were carried out to validate a method of estimating body tissue masses, with a focus on muscle mass, and test the general hypothesis that excessive body protein mobilisation in lactation negatively impacts litter growth, sow rebreeding and subsequent reproductive success. Chapter 3 provided an assessment of the agreement between bioelectrical impedance spectroscopy (BIS) with dual energy x-ray absorptiometry (DXA) in sow carcasses. Dual energy x-ray absorptiometry is used to provide a highly accurate prediction of fat and fat-free mass in pigs. Bioelectrical impedance spectroscopy requires calibration against a standard reference method of predicting composition, such as DXA. Due to abattoir requirements in the slaughter process and DXA scanning weight restrictions, validation was carried out on sow carcasses. The BIS was in close agreement with DXA, underestimating total carcase fat-free mass by -0.5 %. Validation in the sow carcase was then followed by validation in the live sow. The agreement between bioelectrical impedance spectroscopy and dilutional measurements in the live sow was assessed in Chapter 4. A second objective of Chapter 4 was to provide a cross-validation of current methods used on-farm to measure body composition against BIS. Experiment 2 was conducted to develop apparent resistivity coefficients for extra- (431.1 ohm.cm) and intra-cellular (1827.8 ohm.cm) water against standard reference tracer dilution methods and a body geometry factor (1.09 ± 0.14) necessary for assessment of body composition. Given that BIS quantifies body fluid masses, validation of BIS was necessary in dry sows. The BIS predictions of fat-free mass were compared against the deuterium dilution method, existing impedance predictors and published prediction equations in the live sow. Method validation revealed mean differences between predicted (BIS) and measured (deuterium dilution method) fat-free mass values ranged from -8.2 to 32.7% but were not statistically different (P > 0.05). The relatively wide limits of agreement suggested BIS as an impractical option for assessing body composition in the individual sow. Equivalence testing revealed the prediction equations of Dourmad et al. (1997) exhibited the lowest bias and percentage equivalence, with narrow limits of agreement against impedance predictions and BIS. Chapter 5 investigated the use of creatinine, a by-product of muscle metabolism, as a biomarker of muscle mass change. The aim of this experiment was to investigate the potential for serum creatinine to indicate a predicted loss in sow muscle mass over lactation, validated against an increase in serum 3 methyl histidine (3MH) and blood urea nitrogen (BUN), which are markers of dietary and/or body protein breakdown. To further provide an indication of a change in sow body composition, backfat depth at the P2 site was measured using ultrasound and sow condition measured using a sow caliper. Although sows did not experience a statistically significant change in backfat depth, caliper score and serum analytes over lactation (P > 0.05), 3MH concentrations were higher in the sows of a lower body mass at the end of lactation (P < 0.05), which correlated with BUN concentrations (P < 0.001; R2 = 0.691). These data suggested that although sows may have experienced body protein mobilisation, serum creatinine and BUN may have been the net result of dietary and/or body protein breakdown. Serum creatinine was, therefore, not a reliable marker of changes in muscle mass in the testing conditions. Experiments 1 to 3 identified that currently, the most precise prediction of sow body composition on the investigated population is the equation developed by Dourmad et al. (1997). From this point forward, sow body fat and protein mass and their change in lactation were predicted using these equations. Chapters 6 and 7 were conducted to understand the degree of tissue mobilisation sows experience during lactation and the impact on litter performance and subsequent sow reproductive success. The objective of Experiment 4 was to use diet type (standard commercial formulations of gestation diet, 13.0 MJ dietary energy (DE)/kg 0.42 standardised ileal digestible (SID) g lysine/MJ DE versus lactation diet, 14.3 MJ DE/kg 0.62 g SID lysine/MJ DE) and feed allowance (reduced allowance of 7.5 kg/d versus ad libitum-fed) to impose varying levels of DE and SID Lys intake throughout lactation. Although dietary treatments applied were able to impose a calculated negative energy and Lys balance on lactating sows (parities 2-6), dietary treatments did not alter change in sow body fat or protein mass over lactation, litter growth, reproductive hormones (insulin and IGF-1) or total piglets born in the subsequent litter (P > 0.05). There was a tendency for sows which were fed the reduced allowance to have an extended time between weaning and next service by 0.3 ± 0.2 days (mean ± SEM) (P < 0.010). Under the current experimental conditions, a calculated negative energy and Lys balance over lactation had little to no impact on litter performance and subsequent sow reproduction. Sows in this experiment experienced minimal body tissue mobilisation. It was expected that sows would have experienced body tissue catabolism in response to daily changes in energy and Lys requirements as lactation becomes a priority and energy is partitioned for milk production. A more detailed investigation into energy and Lys requirements of sows fed ad libitum, to determine sow body composition changes and litter growth at different stages of lactation was required. Experiment 5 was designed to evaluate the impact of a two-diet feeding program in lactation on sow body mobilisation, litter growth, rebreeding and subsequent reproduction. Sows were either fed a lactation diet to weaning, a gestation diet to weaning, or a gestation diet to day 6 of lactation and a lactation diet from day 7 to weaning. There was no dietary treatment response over the first 6 days of lactation on sow body composition or litter growth. From day 7 to weaning, sows fed the gestation diet lower in DE and SID Lys content tended to lose body protein (P > 0.10) and display a reduced litter growth (P < 0.05). Overall loss in body composition across all groups were minimal with no negative impacts on rebreeding or subsequent reproduction. A two-diet feeding program in lactation, which transitioned from a gestation to a lactation diet on day 7, had no impact on litter growth or changes in body composition, rebreeding or reproductive success. In conclusion, data from this thesis showed that although BIS provided an accurate measure of fat-free mass in sow carcasses, this technology was not suitable for measures in the individual sow due to inherent biological and methodological variability in the live animal. Serum creatinine was not able to provide a reliable prediction of change in sow muscle mass as concentrations may have been influenced by both dietary Lys intake and/or body protein turnover. The prediction equations of Dourmad et al. (1997), based on body weight and a measure of backfat depth at the P2 site, provided the most reliable indication of sow body fat and protein mass against current impedance predictors and published prediction equations. Despite imposing varying degrees of dietary energy and Lys restrictions, sows used in these experiments did not excessively mobilize body tissues during early or late lactation with little to no impact on litter performance and sow reproductive success. It would appear that at least with the sows used in these experiments and the nutritional treatments imposed, there was limited lactational catabolism thus allowing opportunity for feeding strategies to target the growth and survival of piglets without compromising rebreeding and total piglets born in the subsequent litter. Further experiments are recommended to validate a prediction equation for estimating body protein mass using measures of body weight and loin muscle depth in sows across different parities and stages of lactation. There is also a need to update nutritional requirements of the leaner, lactating sow with a focus on delivering two diets formulated to meet DE and SID Lys requirements for maintenance in the first 6 days of lactation and rapid litter growth through to weaning. Future research is required to examine the impact of reduced body composition loss during lactation on subsequent reproductive cycles and sow longevity in the herd.
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37

Loizillon, Guillaume. "Modes de description des sons et synthese sonore". Paris 8, 1996. http://www.theses.fr/1996PA081164.

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Le son est defini comme la conjonction d'un phenomene physique et d'une realite physiologique et psychologique. Pourtant, seule la perception auditive fonde le phenomene acoustique dans sa specificite sonore. La mise en parallele des grandeurs physiques avec les donnees du sens de l'ouie est une conception limitee. Les travaux avances en psycho-acoustique montrent que l'audition ne peut se resumer en l'etablissement de ce reseau. Il faut considerer les sons comme les composantes d'une scene auditive dont la musique est un modele particulier. Il devient alors necessaire d'analyser les specificites du son musical, en suivant les etapes historiques qui ont conduit a une definition de celui-ci, articulee sur les parametres de hauteur, de duree d'intensite et de timbre. Cette derniere composante apparait comme valeur centrale dans la musique contemporaine. Ce basculement d'une musique des hauteurs vers une musique du timbre, prend un caractere decisif avec l'apparition des techniques electriques du son. En un siecle, elles ont apporte au musicien une panoplie d'outils qui utilisent les virtualites du son transforme en electricite, puis en informations numeriques. Au sein de ces nouvelles ressources, la seconde partie du travail se consacre a la synthese sonore. Sont abordes les differents modes de synthese sonore a travers un ensemble d'exemples sonores realises avec deux categories de programmes: les modes de synthese de signal, ou l'on specifie les differentes parametres de l'onde acoustique. Les modes de synthese par modeles physiques ou l'on decrit l'interaction entre differents objets modelises : cordes, plaques, plectres, anches. . . Par-dela la mise en oeuvre de processus techniques, l'objectif de ce travail est de demontrer que l'activite de synthese sonore est un veritable enjeu pour la composition qu'il serait une erreur de penser comme un seul produit de la technologie
SOUND IS DEFINED AS THE JUNCTION BETWEEN A PHYSICAL PHENOMENON AND PHYSIOLOGICAL A PSYCHOLOGICAL REALITY. MEANWHILE, ONLY THE AUDITIVE PERCEPTION - ESTABLISHES ACOUSTIC PHENOMENON ITS SOUNDING SPECIFICITY. LINKING PHYSICAL DIMENSIONS WITH ELEMENTS OF HEARING IS A RESTRICTED IDEA. LEADING WORKS IN PSYCHOACOUSTIC SHOW THAT AUDITION CANNOT BE REDUCED TO THIS CONCEPT. SOUNDS HAVE TO BE CONSIDERED AS THE ELEMENTS OF AN AUDITION SCENE OF WHICH MUSIC IS A SPECIFIC CASE. THUS, IT IS NECESSARY TO ANALYSE SPECIFICITIES OF MUSICAL SOUND, FOLLOWING THE HISTORICAL WAY THAT LEAD TO A DEFINITION ARTICULATED AROUND PARAMETERS OF PITCH, DURATION, INTENSITY AND TIMBRE. THIS LAST DIMENSION APPEARS AS A CENTRAL VALUE IN CONTEMPORARY MUSIC. THIS TRANSITION FROM A MUSIC OF PITCH TO A MUSIC OF TIMBRE, TAKES A DECISIVE DIMENSION with THE BIRTH OF ELECTRICAL SOUND TECHNICS. IN THE TIME OF ONE CENTURY THOSE TECHNICS BROUGHT MUSICIANS A COLLECTION OF TOOLS THAT USES THE CAPACITIES OF SOUND TRANSFORMED IN ELECTRICITY THEN IN DIGITAL INFORMATION. AMONG THOSE RESSOURCES, THE SECOND PART OF THIS WORK TAKES SOUND SYNTHESIS AS SUBJECT. WE DISCUSS IN THIS PART OF DIFFERENT SYNTHESIS METHODS AND WE SHOW DIFFERENT PROGRAMMING EXAMPLES, SEPARATED IN TWO CATEGORIES. METHODS OF SIGNAL SYNTHESIS IN WHICH ALL THE PARAMETERS OF ACOUSTIC WAVES MUST BE SPECIFIED. PHYSICAL MODELING WHERE THE INTERACTION BETWEEN OBJECTS LIKE STRING, PLATE, TUBE, MASS, IS DESCRIBED BEYOND A TECHNICAL PROCESS, THE GOAL OF THIS WORK IS TO DEMONSTRATE THAT SOUND SYNTHESIS IS A GENUINE PART OF MUSICAL COMPOSITION TERRITORY. IT WOULD BE A MISTAKE TO REGARD ONLY AS A TECHNOLOGICAL PRODUCT
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38

Eimutytė, Jurgita. "Paršavedžių apsivaisinimo įtaka ūkio ekonominiams rodikliams". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070419_154824-38244.

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Problem of inquiry: There are no named sow‘s impregnation influence for Lithuanian swine-breeding farms. When sows are non-impregnate fall all manufacture efficiency, getting less gaining’s and enlarge the prime cost for products. Goals of inquiry: Identify sow‘s impregnation efficiency influence reasons, rate their influence for swine-breeding economics indexes. Inquiry tasks: • Identify leading reasons for saw‘s impregnation. • Rate with sow connected actions influence for impregnation indexes. • Rate with boar connected actions influence for impregnation indexes. • Rate with farm factors connected actions influence for impregnation indexes. • Rate sow‘s non-impregnation influence for swine-breeding farm‘s economic process. Conclusions: In this prospecting work were analyzing sow‘s impregnation influence for Lithuanian swine-breeding farm‘s economic process. Clear, that for impregnation has influence genetic indexes and feature of the farm. Sows impregnation directly has influence for farms practices profitability. If enlarge sows non-impregnation percentage, then profitability is lowing and enlarge price for shoats.
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39

Hung, I.-Fen. "INFLUENCES OF SUPPLEMENTING A MANNAN OLIGOSACCHARIDE CONTAINING PRODUCT TO PIG DIETS ON SOW AND WEANLING PIG PERFORMANCE". UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_theses/636.

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The objective of these studies was to evaluate the effect of supplying mannan oligosaccharides (MOS) to pig diets on both weanling pig and sow performances. Nursery pigs challenged with LPS to stimulate an immune challenge had increased body temperature and respiratory rate as well as elevated serum cortisol and TNF-α concentration, MOS-supplemented pigs had a lower rectal temperature and respiratory rate which implied that MOS improves some aspect of the immune function of piglets. MOS supplementation in sow diets during late gestation and lactation had no effect on litter size, but the piglets from MOS-fed sows were heavier at birth (P = 0.04), at weaning (P = 0.03), and during the entire nursery period (P < 0.01). Moreover, milk fat and protein levels as well as the Ig concentrations in milk from MOS-fed sows were numerically higher (2 – 12%; P > 0.10) than control sows. Overall, MOS supplementation in the nursery diet may have limited effects on the growth performance, but may have some beneficial influence on pigs under immune challenge. Furthermore, including MOS to the sow diet during late gestation and lactation can potentially improve piglet body weight as well as growth during the suckling and nursery periods.
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40

Graça, Orlanda Gisela. "La déconstruction du droit d'auteur sous prétexte de technologie numérique". Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT3009.

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L'avènement des technologies numériques, notamment des réseaux numériques, a servi de prétexte pour introduire dans le droit d'auteur des réformes qui mènent à une mutation profonde de ce droit. Un précédent a été créé par l'inclusion des logiciels et des bases de données électroniques dans son champ de protection ; ce sont de créations strictement fonctionnelles, qui ne devraient pas appartenir à la catégorie « oeuvre de l'esprit ». Cela ne pouvait qu'engendrer une distorsion du critère de l'originalité. En outre, la nature de ces objets imposera d'adapter le régime juridique ainsi que les règles de titularité. Naquit ainsi, au sein du droit d'auteur classique, un paradigme spécial que tout rapproche du copyright américain. Centré sur l'investisseur et sur la notion de fixation, il est désormais en train de contaminer le droit d'auteur. Au demeurant, on ne peut négliger l'influence capitale du copyright américain dans tout ce processus de construction et d'extension puisque certains de ses concepts et principes se retrouvent aujourd'hui dans le droit d'auteur. On assiste à un véritable mouvement de déconstruction du droit d'auteur personnaliste hérité de la Révolution française et dont l'apogée fut la loi du 11 mars 1957. Nous mettrons en évidence les divers facteurs qui ont agi et qui agissent conjointement aux niveaux national, communautaire et international, tout en démontrant que si l'environnement numérique pose certes des difficultés pour l'exploitation des oeuvres de l'esprit, le droit d'auteur, centré sur l'auteur et fondé sur la notion de communication au public, était bel et bien capable d'y faire face sans avoir besoin d'ébranler ses assises
The advent of digital technologies, including digital networks, served as a pretext to introduce author's right reforms that lead to a profound change in this right. A precedent was set with the inclusion of software and electronic databases in the field of protection as these are strictly functional creations that should not belong to the category of "oeuvre de l'esprit". This inclusion leads to a distortion of the criteria of originality as well as the need to change both the rules of ownership and the legal regime of author's rights. Consequently a special paradigm, similar to U.S. copyright, is born inside the classical author's right system. Focused on the investor and in the notion of fixation, this special right of sotware and database now contaminates the author's right system. We cannot ignore the important influence of American concept of copyright in the whole process of construction and expansion of this special paradigm as some of its concepts and principles are reflected in today's notion of author's rights. We are witnessing a movement of deconstruction of the author's rights personalist legacy of the French Revolution which culminated in the Act of 11 March 1957. We will highlight the various factors that have acted and act jointly at national, EU and international level to produce this result, while demonstrating that while the digital environment certainly poses difficulties for the use of works of authorship, the author's right, author-centered and based on the notion of communication to the public, would indeed be able to cope with digital environment without the need to undermine its foundations
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41

Legault, Jean-François. "Étude par photoluminescence résolue en temps des mécanismes de relaxation inter-sous-bandes dans des structures à puits quantiques multiples". Sherbrooke : Université de Sherbrooke, 1998.

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42

Neal, Michael Scott. "Effects of an X-autosome translocation on the reproductive performance of the sow". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31856.pdf.

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43

Mohammad, Majdi. "Le changement et le sous-développement socio-économique dans la société paysanne de Cisjordanie : l'analyse des mécanismes de la reproduction de la famille rurale sous l'occupation". Paris 10, 1994. http://www.theses.fr/1994PA100051.

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Le but de cette thèse est d'étudier le changement dans les conditions de la production et la reproduction des familles rurales sous l'occupation israélienne en Cisjordanie. La thèse contient deux parties. La première concerne l'analyse des transformations socio-économiques du monde rural palestinien à l'échelon national. Il s'agit d'une description macroéconomique qui place l'agriculture palestinienne dans l'ensemble de l'économie du pays en précisant ses difficultés internes et externes, et sa place dans l'économie de la famille rurale et la vie du village. La deuxième partie concerne l'analyse microsociologique, au niveau local, des impacts de l'univers politico-économique instable sur la famille rurale et la société villageoise, depuis l'occupation. Dans cette partie, l'unité d'observation est la famille en tant que cellule de production et de gestion de ressources en vue de sa reproduction biologique, économique et sociale
The aim of this thesis is the study of the changes of the conditions of rural families’ production and reproduction under israelian occupation in the west-bank. The thesis contains two parts. The first one concerns the analysis of rural Palestinian socio-economic transformations at national scale. It is a macroeconomic description which places Palestinian agriculture in the economy of the whole country precising its internal and external difficulties, and its place in the economy of rural families and village life. The second part concerns the micro sociologic analysis, on local scale, of the instable political economic universe impacts on the rural family and the village society since occupation. In this part, the family is the observation unity as the cell of production and resources administration with an eye on its biologic, social and economic reproduction
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44

Arié, Emmanuelle. "Contribution à l'étude des effets de l'électro-osmose sur les propriétés physico-chimiques et mécaniques de l'argile de Saint-Hilaire". Sherbrooke : Université de Sherbrooke, 2001.

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45

Embury, Darrelle. "Reproductive performance of early-weaned gilts and first parity sows fed differing patterns of feed intake during gestation and lactation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ45041.pdf.

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46

Zénouda, Hervé. "Images et sons dans les hypermédias : de la correspondance à la fusion". Paris 13, 2006. http://www.theses.fr/2006PA131013.

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Nous chercherons à souligner, dans ce travail, les continuités et les ruptures qu’apporte le numérique dans le rapport qui se crée entre les images et les sons. Depuis l’influence mutuelle des arts graphiques et des arts sonores en peinture jusqu’aux hypermédias aujourd’hui, on peut repérer une dynamique de convergence toujours plus affirmée des deux représentations. Si le numérique, avec son codage discret, est un moment fort de cette trajectoire, il engendre différents modes de communication spécifiques : interactivité, générativité, simulation, qui chacun, à sa manière, modifie les rapports entre les deux modalités, comme autant d’étapes vers une fusion des conditions de production. L’évolution de cette relation concerne autant le concepteur (qui manipule une ‘matière audiovisuelle’ toujours plus riche) que l’utilisateur (apparition de nouvelles applications, évolution des fonctions de recherche documentaire …) et modifie la nature même du média : plus vraiment une image et plus vraiment un son, cette fusion engendre l’apparition d’un nouvel objet audiovisuel composite, structuré et complexe
The goal of this work is to underline the continuities and breaks that digital technology brings to the relation between pictures and sounds. From the mutual influence of graphic and sound arts on painting to the hypermedia today, we can easily trace an ever-stronger convergent momentum between these two media. Digital technology, with its discrete common coding, is a strong point of this evolution, it still generates different specific ways of communicating: interactivity, generativity, and simulation. Each of them, in its own way, changes the relations between both representations (image and sound), as different steps towards a fusion of the production conditions. This relationship’s evolution concerns as much the designer (who manipulates an ever-richer “audiovisual material”) as the user (new applications appear, documentary search functions evolve…) and changes the nature of the medium itself : not anymore a picture nor a sound, this fusion creates a new composite audiovisual object, structured and complex
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47

Lu, Ning. "LONG-TERM EFFECTS OF DIETARY COPPER SOURCE AND LEVEL ON PERFORMANCE AND HEALTH OF SOWS AND PIGLETS". UKnowledge, 2018. https://uknowledge.uky.edu/animalsci_etds/85.

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The objectives of this study were to investigate the long-term effects of feeding increasing supplemental levels (20, 120, or 220 mg/kg) of dietary copper (Cu) as tribasic copper chloride (TBCC) or copper sulfate (CuSO4) on performance, antioxidant status, nutrient digestibility, and trace mineral deposition of sows and piglets; as well as to assess nursery dietary Cu levels on growth performance and response to immunological challenge in nursery pigs from sows fed either high or low Cu diets. In the long-term sow experiment, sows fed TBCC diets had greater adjusted weaning weight for litter and piglet (P < 0.10), as well as adjusted litter and piglet weight gain (P < 0.10) when compared to sows that received CuSO4 diets. Increasing dietary Cu level linearly increased live born piglet weight (P = 0.06). Sows fed TBCC diets had lower apparent total tract digestibility (ATTD) of ether extract (P = 0.01) during late gestation, but greater ATTD of dry matter, nitrogen, and phosphorous during lactation (P < 0.05). Increasing Cu levels linearly increased dry matter digestibility in lactating sows (P = 0.02). Milk from sows fed TBCC diets had a greater concentration of protein (P = 0.02) than that from sows fed CuSO4 diets. Increasing Cu levels increased levels of milk fat and Cu (linear, P < 0.05); but linearly decreased lactose and Zn levels (P < 0.05). Lactating sows fed TBCC diets had a greater activity of Cu/Zn superoxide dismutase (SOD) and ceruloplasmin in serum than those fed CuSO4 diets (P < 0.05). Increasing dietary Cu levels increased total and Cu/Zn SOD activity for lactating sows (linear, P < 0.05). Sows fed TBCC diets had lower concentrations of Cu (P = 0.04), but higher concentrations of iron and manganese (P < 0.05) in the liver, when compared to those fed with CuSO4 diets. In addition, liver Cu concentrations increased with increasing dietary Cu levels (linear and quadratic, P < 0.05). Increasing dietary Cu levels resulted in the elevation of concentrations and contents of Cu in the liver of weanling piglets (linear, P < 0.0001). In the nursery pig experiment, pigs from sows fed 120 mg/kg Cu diets had greater ADG from d 0 to 14 (P < 0.05), and tended to have greater ADG in the overall period (P < 0.08), when compared to pigs from sows fed 20 mg/kg Cu diets. During the lipopolysaccharide challenge period, the challenged pigs from sows fed 120 mg/kg Cu had a greater overall rectal temperature than those from sows fed 20 mg/kg Cu (P = 0.01). Also, the challenged pigs fed with 220 mg/kg Cu diets had greater serum tumor necrosis factor-alpha concentration over time as compared to those fed 20 mg/kg Cu diets (P = 0.03). In summary, the TBCC may be a superior Cu source compared to CuSO4 regarding reproductive performance, and higher dietary Cu levels result in greater birth weight of piglets; furthermore, high Cu levels in sow and nursery diets promote growth performance of nursery pigs and affects their responses to immunological challenge.
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48

Molter-Gérard, Christine. "La Régulation différentielle de la synthèse et de la libération des gonadotropines chez la brebis passe-t-elle par une stimulation préférentielle de sous-populations cellulaires gonadotropes ?" Tours, 1999. http://www.theses.fr/1999TOUR4003.

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Au cours du cycle oestrien, le rapport des taux plasmatiques des gonadotropines lh/fsh varie. Cette variation, résultat d'une synthèse et une sécrétion différentielles des gonadotropines, assure le bon fonctionnement du cycle. Chez la brebis, ces hormones sont localisées dans des cellules bihormonales (contenant lh et fsh) ou monohormonales lh. Cette hétérogénéité de stockage pourrait constituer un support de la régulation différentielle. Nous avons étudié l'effet de facteurs impliques dans la régulation différentielle (gnrh, oestradiol et activine), sur la répartition de ces sous-populations cellulaires. L'administration de pulses de gnrh a des brebis dépourvues de gnrh induit une libération pulsatile de lh, sans modifier la libération de fsh, quelle que soit la fréquence (1pulse/h-1pulse/6h). De plus, l'administration de gnrh a une fréquence faible favorise l'apparition de cellules bihormonales, provenant probablement de cellules monohormonales lh synthétisant fsh sous l'action du gnrh. Ainsi, une fréquence faible de gnrh stimulerait préférentiellement la synthèse de fsh, alors que la synthèse de lh semble favorisée par une fréquence élevée. L'injection d'oestradiol induit une diminution des taux de lh et fsh, suivie d'un pic de libération. L'effet inhibiteur étant accompagne d'une diminution de la proportion de cellules bihormonales, l'oestradiol semble inhiber la synthèse des gonadotropines spécifiquement dans ces cellules bihormonales. . De plus, le pic de libération de lh et fsh est suivi d'une diminution du pourcentage de cellules bihormonales, suggérant fortement l'implication de ces cellules dans la sécrétion des gonadotropines. Le pourcentage de cellules bihormonales est également augmente avec un traitement par l'activine in vitro. L'ensemble de ces résultats suggère l'existence d'un rôle fonctionnel des sous-populations gonadotropes dans la sécrétion des gonadotropines, avec un passage possible d'une sous-population a l'autre en fonction des conditions hormonales.
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49

L'Archevêque, Cindy. "Étude de la cristallisation sous tension du mélange poly ([epsilon]-caprolactone)/poly (chlorure de vinyle) par mesures de biréfringence". Sherbrooke : Université de Sherbrooke, 2004.

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50

Suriyasomboon, Annop. "Herd investigations on sperm production in boars, and sow fertility under tropical conditions - with special reference to season, temperature, and humidity /". Uppsala : Dept. of Clinical Sciences, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200572.pdf.

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