Journal articles: 'Fecundity'

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Parkin, Justine. "Fecundity." Environmental Humanities 9, no. 2 (November 1, 2017): 460–63. http://dx.doi.org/10.1215/22011919-4215423.

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Grover, Stephen. "Cosmological Fecundity." Inquiry 41, no. 3 (September 1998): 277–99. http://dx.doi.org/10.1080/002017498321779.

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Paxman, David. "Our Fecundity." Dialogue: A Journal of Mormon Thought 26, no. 3 (October 1, 1993): 88–89. http://dx.doi.org/10.2307/45228662.

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Mohammed, Titaouine, D. E. Gherissi, Chergui Moussa, and Mohamdi Hanane. "Influence of Region on Some Reproductive Parameters in Ouled Djellal Sheep." Jurnal Ilmu Ternak dan Veteriner 28, no. 4 (December 7, 2023): 220–26. http://dx.doi.org/10.14334/jitv.v28i4.3211.

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The present study aims to assess the reproductive performance of Ouled Djellal ewes at four different Biskra locations: El Hadjeb, SidiOkba, Ouled Djellal, and Chaiba.Â All flocks were kept under extensive management.Â For this study, 357 clinically healthy and non-pregnant Ouled Djellal ewes have been used.Â Mating was practiced in an accessible mode, conducted over two months: May and June 2015 (61 days) for all herds. Â The total number of lambing ewes and lambs in all flocks was determined during the lambing period. We compared fertility, fecundity, and prolificacy rates using the Ï‡2 test to verify the relationshipbetween the measured rates and the four sites and multiple comparisons that revealed significant differences.Â The variables assessed in this study encompassed fecundity, prolificacy, and fertility.Â The overall mean values obtained were 78% for fecundity, 117% for prolificacy, and 92% for fertility. These averages were significantly lower than those observed in intensively managed herds. Â However, the lowest rates were recorded at site 4 (Chaiba), with65% for fertility, 109% for prolificacy, and 71% for fecundity.Â The results of this study clearly show that the region has a significant effect on fertility (P= 0.001) and fecundity (P= 0.0001) but no significant effect on the prolificacy rate (P= 0.074).

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Shehu, Muhammad Ahmad, Muhammad Bashir Abdullahi, Mohammed Danlami Abdulmalik, and Opeyemi Aderike Abisoye. "User Embedding Long Short-Term Model Based Fecundity Prediction Model Using Proposed Fecundity Dataset." East African Journal of Interdisciplinary Studies 6, no. 1 (February 20, 2023): 37–53. http://dx.doi.org/10.37284/eajis.6.1.1099.

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Fecundity prediction is a process that helps couples to understand their fertility status. Fecundity prediction as a domain could be supported by developed intelligent models using a computational method and fecundity data. Although fecundity data and models have been proposed, the problem of low data size and dimensionality of the proposed fecundity dataset has been identified due to the data collection approaches used and the problem of using a weak subfertility definition in the development of a User-embedding LSTM-based fecundity prediction model. To solve the identified problems, this study proposed a fecundity dataset by adopting a hybrid data collection approach using the strengths and disregarding the setbacks of existing data collection approaches and then proposed an improved User-embedding LSTM-based fecundity prediction model based on an improved subfertility definition. A large size fecundity dataset was generated and used for the implementation and evaluation of the existing and proposed LSTM-based fecundity prediction models and the proposed model generated better AUC-ROC evaluation results

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NEAL, A. T. "Male gametocyte fecundity and sex ratio of a malaria parasite, Plasmodium mexicanum." Parasitology 138, no. 10 (July 15, 2011): 1203–10. http://dx.doi.org/10.1017/s0031182011000941.

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SUMMARYEvolutionary theory predicts that the sex ratio of Plasmodium gametocytes will be determined by the number of gametes produced per male gametocyte (male fecundity), parasite clonal diversity and any factor that reduces male gametes' ability to find and combine with female gametes. Despite the importance of male gametocyte fecundity for sex ratio theory as applied to malaria parasites, few data are available on gamete production by male gametocytes. In this study, exflagellating gametes, a measure of male fecundity, were counted for 866 gametocytes from 26 natural infections of the lizard malaria parasite, Plasmodium mexicanum. The maximum male fecundity observed was 8, but most gametocytes produced 2–3 gametes, a value consistent with the typical sex ratio observed for P. mexicanum. Male gametocytes in infections with higher gametocytaemia had lower fecundity. Male fecundity was not correlated with gametocyte size, but differed among infections, suggesting genetic variation for fecundity. Fecundity and sex ratio were correlated (more female gametocytes with higher fecundity) as predicted by theory. Results agree with evolutionary theory, but also suggest a possible tradeoff between production time and fecundity, which could explain the low fecundity of this species, the variation among infections, and the correlation with gametocytaemia.

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Byrne, Susan, Mark Heverin, Peter Bede, Marwa Elamin, and Orla Hardiman. "Fecundity in ALS." Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration 15, no. 3-4 (January 31, 2014): 204–6. http://dx.doi.org/10.3109/21678421.2013.865237.

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Beardsley, Tim. "Fear and Fecundity." Scientific American 275, no. 6 (December 1996): 36. http://dx.doi.org/10.1038/scientificamerican1296-36.

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Komova, N. I. "Relationship between Fecundity and the Number of Vertebrae in the Roach <i>Rutilus rutilus</i> of the Rybinsk Reservoir." Биология внутренних вод 4, no. 4 (July 1, 2023): 457–63. http://dx.doi.org/10.31857/s0320965223040125.

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The data on the number of vertebrae in the vertebral column regions in different relative fecundity groups of roach are given. The average value of the number of vertebrae in the abdominal region turned out to be the smallest in low fecundity fishes. When comparing the average values of relative fecundity in females with different numbers of vertebrae in the vertebral column, a group of low fecundity fishes was identified. In it, individuals with 17 vertebrae in the abdominal region had a statistically significantly lower relative fecundity, and those with 16 in the caudal and a total of 40 vertebrae in the vertebral column had a significantly higher fecundity than individuals with a different number of vertebrae in these regions. In highly fecundity females, no differences in fecundity between fish with different numbers of vertebrae in regions were noted.

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Hannah, Robert W., Stephen A. Jones, and Michele R. Long. "Fecundity of the ocean shrimp (Pandalus jordani)." Canadian Journal of Fisheries and Aquatic Sciences 52, no. 10 (October 1, 1995): 2098–107. http://dx.doi.org/10.1139/f95-803.

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Fecundity of the ocean shrimp Pandalus jordani was analyzed from eight samples from the years 1989–1993 and compared with historical fecundity data for this species. Linear regressions of loge fecundity on loge carapace length from the 1989–1993 samples had significantly different slopes. Interannual variation in fecundity exceeded that found between areas within the same year, making it difficult to determine if the observed variation in fecundity resulted from geographic location or interannual variation. No consistent differences between the length–fecundity relationships of the recent and historical samples were demonstrated. A graphical comparison of fecundity with sea level height data provided preliminary evidence that sea bottom temperature may be influencing shrimp fecundity. Egg production, estimated from the length–fecundity relationships and from size and sex composition data from the commercial catch, showed wide variation between years and areas. Variation in sex composition explained roughly 62% of the variation in egg production. Egg production estimates, derived from a pooled length–fecundity relationship, deviated from estimates based on the individual samples by ± 13–18%. These deviations were considered to be a minor source of added variance when compared with other sources of variation in the total egg production of ocean shrimp.

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van Damme, Cindy J. G., Anders Thorsen, Merete Fonn, Paula Alvarez, Dolores Garabana, Brendan O'Hea, José R. Perez, and Mark Dickey-Collas. "Fecundity regulation in horse mackerel." ICES Journal of Marine Science 71, no. 3 (October 18, 2013): 546–58. http://dx.doi.org/10.1093/icesjms/fst156.

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Abstract Egg production methods have been used successfully in the provision of advice for fisheries management. These methods need accurate and unbiased estimates of fecundity. We explore the reproductive strategy of horse mackerel and estimation of fecundity. Fecundity and fecundity regulation in relation to condition was investigated over a number of years. Fulton's K, lipid content, and hepatosomatic index increased after the start of spawning, though decreased again at the end of spawning. The increase in the gonadosomatic index, fecundity, and body condition after the onset of spawning suggests that horse mackerel utilizes food resources during the spawning season and might be an income breeder. However, the decline in K and lipid before the spawning season suggests that the first batch of oocytes is developed on stored energy. Fecundity varied between years and within a spawning season. Over latitude, variations in fecundity were small. K and lipid content are not reliable indices as proxy for fecundity. Batch fecundity appears to be heterogeneous across the spawning season but homogeneous across latitude. The homogeneity of batch fecundity over latitude could indicate that the daily egg production method is an appropriate approach for estimating the abundance of a wide ranging species, as horse mackerel.

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Hossian, Shajjad, Sudip Bhattacharya, Md Atiar Rahman, Rashedul Islam, Rabeya Yesmin, Salina Akhter Sume, and Md Moniruzzaman. "Fecundity estimation of Indian Potasi, Neotropius atherinoides in Bangladesh." Research in Agriculture Livestock and Fisheries 6, no. 3 (January 1, 2020): 421–29. http://dx.doi.org/10.3329/ralf.v6i3.44808.

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Fecundity estimation has obvious significance in aquaculture, since the size of brood stock, amount of rearing facilities and necessity of other equipment’s are dependent on fecundity. The study has been conducted on fecundity estimation of Indian potasi, Neotropius atherinoides, based on 202 females collected from the Kangsha River flowing through Netrokona district during the period from January to June 2013. The standard length (SL) range of female were 47-66, 50-64, 57-68, 50-66, 56-66 and 60-76 mm and range of body weight were 1.07-3.56, 1.23-3.35, 2.36-3.81, 1.69-4.31, 2.33-5.59 and 3.18-5.14 g in January, February, March, April, May and June, respectively. The mean Gonado somatic indices (GSI) were very low from January to March but these were abruptly high during subsequent three months. Based on mean GSI the spawning season of this species was assumed from April to June over the study period. Scatter plot of standard length with corresponding GSI revealed that the minimum length of mature female was 50 mm SL. Egg diameter frequency distribution of a mature ovary showed almost only one major mode of egg size suggested that the fish is a single spawner, and summation of eggs in that mode was regarded as the fecundity of a female Indian potasi. The regression equation of the relationship between standard length and fecundity was as, Fecundity = 0.0017 SL 3.55. The relative fecundity and the absolute fecundity of a fish having SL of 62 mm was 1477 per g and 3921, respectively based on F-SL relationship. The relationship between body weight and fecundity was as, Fecundity = 1371.3 BW-650.8. The absolute fecundity of a fish having BW of 3.51 g was 4162 respectively based F-BW relationship. The relationship between ovary weight and fecundity was as, Fecundity = 6244.3 OW + 967.52. The absolute fecundity of a fish having ovary weight of 3.51 g was 7211 based F-OW relationship. The correlation coefficient of all above analyses were very high (>0.755) attributing that standard length, body weight and gonad weight were highly positively correlated with fecundity of Indian Potasi, Neotropius atherinoides. Res. Agric., Livest. Fish.6(3): 421-429, December 2019

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Kennedy, J., P. R. Witthames, and R. DM Nash. "The concept of fecundity regulation in plaice (Pleuronectes platessa) tested on three Irish Sea spawning populations." Canadian Journal of Fisheries and Aquatic Sciences 64, no. 4 (April 1, 2007): 587–601. http://dx.doi.org/10.1139/f07-034.

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The fecundity of European plaice (Pleuronectes platessa) in the Irish Sea between 2000 and 2004 was estimated during the spawning season for fish in the three main spawning areas (Liverpool Bay, the Cumbrian coast, and the western Irish Sea) and one small spawning group on the west coast of the Isle of Man. Fecundity was also estimated during September of 2003 and 2004. The aim of this was to assess the variability in fecundity between areas and years in the Irish Sea and also to identify when differences in fecundity become apparent in the maturation cycle. There were variations in fecundity on both the temporal and spatial scales. The greatest variation in fecundity between years occurred in the western Irish Sea, whereas there was no variation between years in the southeastern Irish Sea (Liverpool Bay). There was no difference in fecundity between areas or years during September. The maximum fecundity in plaice is determined by the total weight of the fish at the end of follicle recruitment in the ovary, and differences in the fecundity of each population are the result of different levels of down-regulation in the period between the end of follicle proliferation and spawning.

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Sanchez, Norma E., Jerome A. Onsager, and William P. Kemp. "FECUNDITY OF MELANOPLUS SANGUINIPES (F.) IN TWO CRESTED WHEATGRASS PASTURES." Canadian Entomologist 120, no. 1 (January 1988): 29–37. http://dx.doi.org/10.4039/ent12029-1.

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AbstractOviposition rate (eggs per ♀-degree-day) and fecundity (total number of eggs per ♀) were measured in two populations of Melanoplus sanguinipes (F.) under natural conditions during two seasons (1984, 1985). Differences in fecundity between the two seasons were indirectly associated with differences in time of hatching. In 1985, females hatched earlier and had shorter preoviposition periods, greater longevities, and higher oviposition rates; consequently, fecundity averaged about three-fold greater than in 1984. Longevity appeared to be the most important single determinant of fecundity. Maximum fecundity was 73.2 eggs (equivalent to four pods) and mean fecundity ranged between 10.1 and 28.9 eggs per female.

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Qiu, Tong, Marie-Claire Aravena, Robert Andrus, Davide Ascoli, Yves Bergeron, Roberta Berretti, Michal Bogdziewicz, et al. "Is there tree senescence? The fecundity evidence." Proceedings of the National Academy of Sciences 118, no. 34 (August 16, 2021): e2106130118. http://dx.doi.org/10.1073/pnas.2106130118.

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Despite its importance for forest regeneration, food webs, and human economies, changes in tree fecundity with tree size and age remain largely unknown. The allometric increase with tree diameter assumed in ecological models would substantially overestimate seed contributions from large trees if fecundity eventually declines with size. Current estimates are dominated by overrepresentation of small trees in regression models. We combined global fecundity data, including a substantial representation of large trees. We compared size–fecundity relationships against traditional allometric scaling with diameter and two models based on crown architecture. All allometric models fail to describe the declining rate of increase in fecundity with diameter found for 80% of 597 species in our analysis. The strong evidence of declining fecundity, beyond what can be explained by crown architectural change, is consistent with physiological decline. A downward revision of projected fecundity of large trees can improve the next generation of forest dynamic models.

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Diakov, Yury P. "Fecundity of the Far-Eastern flatfishes Pleuronectiformes. 1. General characterization of fecundity of Pleuronectiformes in the northern part of the Pacific Ocean." Izvestiya TINRO 188, no. 1 (March 30, 2017): 54–88. http://dx.doi.org/10.26428/1606-9919-2017-188-54-88.

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Cited and archive data on fecundity of 31 flatfish species are generalized for the North Pacific. General characterization of the fecundity is presented and correlation between absolute individual fecundity of the females and their body length or age is analyzed and formalized in equation form. Spatial variability of fecundity is described for different species: pacific halibut and starry flounder have the highest absolute fecundity in the eastern Bering Sea and Okhotsk Sea, greenland halibut, yellowfin sole, alaska plaice, sakhalin flounder, longhead dab, and flathead sole - in the Okhotsk Sea, northern rock sole - in the waters at East and West Kamchatka. kamchatka flounder - in the Bering Sea, arrowtooth flounder - in the Pacific waters at North America. So, the Okhotsk Sea is the area where the absolute fecundity of majority wide-spread flatfish species can reach the maximal level. However, the maximal fecundity of longsnouted flounder is higher in the Japan Sea than in the Okhotsk Sea.

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Silva, Nelson Rodrigues, Bianca V. M. Berneck, Helio R. da Silva, Célio F. B. Haddad, Kelly R. Zamudio, Tamí Mott, Renato C. Nali, and Cynthia P. A. Prado. "Egg-laying site, fecundity and degree of sexual size dimorphism in frogs." Biological Journal of the Linnean Society 131, no. 3 (September 15, 2020): 600–610. http://dx.doi.org/10.1093/biolinnean/blaa126.

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Abstract Female fecundity is an important selective force leading to female-biased sexual size dimorphism (SSD) in frogs. Because anurans exhibit diverse reproductive modes, we investigated whether variation in SSD and fecundity are related with oviposition site. We asked whether arboreal breeding species show pronounced female-biased SSD and if, paradoxically, females have lower fecundity because of the costs of carrying oocytes and amplectant males. Conversely, we tested whether species that deposit eggs in concealed sites show less pronounced SSD, because females do not carry males and space limitation may reduce female size and fecundity. Our results showed that, in general, males were approximately 20% smaller than females. However, for species with hidden oviposition sites, males and females exhibited more similar body sizes and arboreal hylids showed more pronounced female-biased SSD. Overall, fecundity was higher in aquatic breeders, as expected, but in hylids, fecundity was smaller in arboreal breeders, which suggests that arboreality may impose restrictions on fecundity. By analysing SSD in a broader and more specific lineage (Hylidae), we found that reproductive microhabitat may also influence female size and fecundity, playing an important role in the evolution of SSD in frogs at different evolutionary scales.

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Agbugui, M. O., S. N. Deekae, and S. J. Oniye. "Sex ratio, gonadal development and fecundity of the grunt, Pomadasys jubelini (Cuvier, 1830) in the new Calabar-Bonny River, Nigeria." Journal of Aquatic Sciences 31, no. 2C (May 10, 2017): 499–507. http://dx.doi.org/10.4314/jas.v31i2c.17.

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The sex ratio, gonadosomatic index, stages of gonadal development and fecundity of the grunt, Pomadasys jubelini in the New Calabar-Bonny River were investigated. P. jubelini had a sex ratio of 1: 2.1 (male to female). Gonadosomatic index ranged from 0.33 to 7.29% with a mean of 2.89+0.08%. High gonadosomatic indices were recorded from September to October, which indicates the production period of the fish. Two stages; maturing and mature were observed for male fish while quiescent, maturing and mature were observed for female fish. Fecundity ranged from 9,085 to 37,926 eggs and a mean of 25,852+432 eggs. This is an indication that P. jubelini has low fecundity. Fecundity-body weight and fecundity-body length were positively correlated. Fecundity-weight relationship was Log F=0.1243+2.74 Log W (r=0.950). Fecundity-length relationship was Log F=0.0247 + Log 1.779 log L=(r=0.114), Fecundity was more related to weight than length. P. jubelini begins spawning during the rainy season in marine and estuarine environments. During this period large number of fingerlings and juveniles are in abundance. The results of this study will assist in increasing the knowledge of the reproductive biology of P. jubelini which is relevant in aquaculture development of the species.Keywords: Fecundity, gonadal development, gonadosomatic index, New Calabar-Bonny River, Pomadasys jubelini

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dos Santos Schmidt, Thassya C., Aril Slotte, James Kennedy, Svein Sundby, Arne Johannessen, Gudmundur J. Óskarsson, Yutaka Kurita, Nils C. Stenseth, and Olav Sigurd Kjesbu. "Oogenesis and reproductive investment of Atlantic herring are functions of not only present but long-ago environmental influences as well." Proceedings of the National Academy of Sciences 114, no. 10 (February 21, 2017): 2634–39. http://dx.doi.org/10.1073/pnas.1700349114.

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Following general life history theory, immediate reproductive investment (egg mass × fecundity/body mass) in oviparous teleosts is a consequence of both present and past environmental influences. This clarification questions the frequent use of season-independent (general) fecundity formulas in marine fish recruitment studies based on body metrics only. Here we test the underlying assumption of no lag effect on gametogenesis in the planktivorous, determinate-fecundity Atlantic herring (Clupea harengus) displaying large plasticity in egg mass and fecundity, examining Norwegian summer–autumn spawning herring (NASH), North Sea autumn-spawning herring (NSAH), and Norwegian spring-spawning herring (NSSH). No prior reproductive information existed for NASH. Compared with the 1960s, recent reproductive investment had dropped markedly, especially for NSAH, likely reflecting long-term changes in zooplankton biography and productivity. As egg mass was characteristically small for autumn spawners, although large for spring spawners (cf. different larval feeding conditions), fecundity was the most dynamic factor within reproductive investment. For the data-rich NSSH, we showed evidence that transient, major declines in zooplankton abundance resulted in low fecundity over several subsequent seasons, even if Fulton’s condition factor (K) turned high. Temporal trends inKslope(Kon total length) were, however, informative. These results clarify that fecundity is defined by (i) dynamics of primary (standing stock) oocytes and (ii) down-regulation of secondary oocytes, both processes intimately linked to environmental conditions but operating at different timescales. Thus, general fecundity formulas typically understate interannual variability in actual fecundity. We therefore argue for the use of segmented fecundity formulas linked to dedicated monitoring programs.

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Diakov, Yury P. "Fecundity of the Far-Eastern flatfishes Pleuronectiformes. 2. Comparative taxonomic analysis: fecundity, abundance and distribution of the species." Izvestiya TINRO 188, no. 1 (March 30, 2017): 89–114. http://dx.doi.org/10.26428/1606-9919-2017-188-89-114.

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Comparative analysis is made for absolute, species-specific and total fecundity of 31 flatfish species in the North Pacific from North America to the Japan Sea. Normally the individuals of larger size have higher fecundity. Similarity between the species by fecundity dynamics in dependence on body length and age is evaluated. Significance of the absolute fecundity for abundance or distribution of the species is discussed. Generally, the species with medium or high fecundity are more abundant than those with low number of eggs. The widest distribution is intrinsic for flatfish species with medium length of the early pelagic stage of their life.

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Bazaz, Asim Iqbal, Tasaduq H. Shah, Farooz A. Bhat, Irfan Ahmad, Nafhat-ul-Arab -, Maheen Altaf, Saima Andleeb, Zaib Hafiz, Bisma Shafi, and Azra Shah. "Assessment of Spawning Fecundity and Its Relationship with Body Parameters of Rainbow Trout (Oncorhynchus mykiss) and Brown Trout (Salmo trutta fario)." International Journal of Bio-resource and Stress Management 13, no. 10 (October 31, 2022): 1115–23. http://dx.doi.org/10.23910/1.2022.3066a.

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The present investigations were carried out at Trout Culture Farm Laribal, Srinagar (J&K Govt.), India during December, 2020. Relationship between length-weight, spawning fecundity and relative fecundity was observed in rainbow trout (O. mykiss) and brown trout (S. trutta fario). The mean length of male rainbow trout was (38.77±1.38 cm) and mean length of (38.05±1.32 cm) was observed in female rainbow trout. While as, the mean length of male brown trout was (38.86±1.41 cm) and for female brown trout mean length of (37.98±1.30 cm) was observed. The mean weight of male and female rainbow trout recorded was 794.6±49.3 g and 766.3±64.3 g respectively, while as, the average weight of male and female brown trout was 772.7±41.4 g and 757.6±57.22 g respectively. The spawning fecundity female-1 of rainbow trout ranged from 2002−2804 eggs and mean relative fecundity of 3.13±0.12 g-1 body weight was observed and for brown trout the spawning fecundity female-1 fish ranged from 961 to 1604 eggs, with a relative fecundity of 1.41 g-1 body weight to 1.56 g-1 body weight. The present study recorded a significant positive correlation between total body length and total body weight of male rainbow trout (r=0.938, p<0.05) and total body length and total body weight of female rainbow trout (r=0.989, p<0.05) and for brown trout a significant positive correlation was recorded between total body length and spawning fecundity, body weight and spawning fecundity was observed. However, relative fecundity formed a significant negative correlation between total length, body weight and spawning fecundity in brown trout.

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Stares, J. C., R. M. Rideout, M. J. Morgan, and J. Brattey. "Did population collapse influence individual fecundity of Northwest Atlantic cod?" ICES Journal of Marine Science 64, no. 7 (October 1, 2007): 1338–47. http://dx.doi.org/10.1093/icesjms/fsm127.

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Abstract Stares, J. C., Rideout, R. M., Morgan, M. J., and Brattey, J. 2007. Did population collapse influence individual fecundity of Northwest Atlantic cod? – ICES Journal of Marine Science, 64:1338 –1347. We examined the influence of population collapse on individual potential fecundity and total population egg production (TEP) of three northwest Atlantic cod (Gadus morhua) populations: northern cod (Divisions 2J3KL), southern Grand Bank cod (NAFO Divisions 3NO), and southern Newfoundland cod (Subdivision 3Ps). Fecundity at length increased in conjunction with population collapse for two (3NO, 3Ps) of the three populations. Subsequent moderate population recovery between the 1990s and 2000s in 3Ps was accompanied by a decrease in fecundity at length. A large decrease in fecundity at length for 3NO during the same time period, despite little or no population recovery, coupled with the fact that there was no obvious difference in fish condition between the two time periods, suggested that density-independent factors could be contributing to the changes in fecundity. Use of pre-collapse fecundity–length relationships to estimate TEP in the post-collapse period resulted in underestimation of TEP by as much as 30% in 3NO and 46% in 3Ps, whereas in 2J3KL, TEP was overestimated by as much as 18%. Although the results do not fully support the hypothesis of an inverse relationship between population size and fecundity, they do demonstrate the variable nature of cod fecundity which, if not accounted for, can lead to erroneous perceptions of stock reproductive potential.

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Rodríguez-Félix, Demetrio, Miguel A. Cisneros-Mata, Daniel Guevara-Aguirre, E. Alberto Aragón-Noriega, and Edgar Alcántara-Razo. "Variability in fecundity of the brown crab, Callinectes bellicosus Stimpson, 1859 (Brachyura, Portunidae), along the coast of Sonora." Crustaceana 91, no. 12 (2018): 1523–36. http://dx.doi.org/10.1163/15685403-00003860.

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Abstract This work analyses how the fecundity of the brown swimming crab, Callinectes bellicosus, varies along the coast of Sonora in the Gulf of California. Ripe female crabs were collected during May 2015 in four zones, and fecundity was determined and compared with carapace width (CW), total body weight (TW) and egg mass weight (MW). TW ranged between 100.5 g and 209.8 g (average = 158.2 g, coefficient of variation (CV) = 23.4%); CW ranged from 97.9 mm to 123.6 mm (average = 113.4 mm, CV = 8.3%); MW varied from 16.4 g to 34.1 g (average = 25.3 g, CV = 20.4%). The total fecundity (number of eggs per female) of C. bellicosus varied from 1 769 195 to 3 739 254 (average = 2 730 217, CV = 22.2%); partial fecundity (number of eggs per g of egg mass) ranged from 100 422 to 117 130 (average = 107 721, CV = 5.1%). A general north-south decrease in fecundity was observed, although the least fecund females were found in central Sonora (Kino Bay). The most significant linear correlation was found between total fecundity vs. egg mass weight. Total fecundity was better explained by a Von Bertalanffy model, with a maximum average fecundity of 3.7 million eggs for a female of 230 g total weight.

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HASHIMOTO, K., R. UCHIKAWA, T. TEGOSHI, K. TAKEDA, M. YAMADA, and N. ARIZONO. "Immunity-mediated regulation of fecundity in the nematodeHeligmosomoides polygyrus– the potential role of mast cells." Parasitology 137, no. 5 (December 22, 2009): 881–87. http://dx.doi.org/10.1017/s0031182009991673.

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SUMMARYPrevious studies have shown that host immunity regulates the fecundity of nematodes. The present study was aimed at clarifying the reversible nature of fecundity in response to changes of immunological status and to determine which effector cells are responsible for compromising fecundity inHeligmosomoides polygyrus. Enhanced fecundity was observed in immunocompromised SCID andnu/numice compared to those in the corresponding wild-type mice, with significantly fewer numbers of intrauterine eggs produced in the wild-type than in the immunodeficient mice. When 14-day-old adult worms from BALB/c mice were transplanted into naïve BALB/c mice, their fecundity increased significantly as early as 24 h post-transplantation, but not when they were transferred into immune mice, suggesting the plastic and reversible nature of fecundity in response to changes in host immunological status. In mast cell-deficientW/Wvmice, nematode fecundity was significantly higher than in mast cell-reconstitutedW/Wvor +/+ mice. The serum levels of the mast-cell protease mMCP1 were markedly increased in the wild-type as well as the mast cell-reconstitutedW/Wv, but not in theW/Wv, SCID, ornu/numice during infection. These findings raise the interesting possibility that certain activities of mast cells, either directly or indirectly, regulate parasite fecundity during infection.

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García-Villada, Libertad, and John W. Drake. "Experimental selection reveals a trade-off between fecundity and lifespan in the coliphage Qß." Open Biology 3, no. 6 (June 2013): 130043. http://dx.doi.org/10.1098/rsob.130043.

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Understanding virus evolution is key for improving ways to counteract virus-borne diseases. Results from comparative analyses have previously suggested a trade-off between fecundity and lifespan for viruses that infect the bacterium Escherichia coli (i.e. for coliphages), which, if confirmed, would define a particular constraint on the evolution of virus fecundity. Here, the occurrence of such a trade-off is investigated through a selection experiment using the coliphage Qß. Selection was applied for increased fecundity in three independent wild-type Qß populations, and the ability of the virions to remain viable outside the host was determined. The Qß life-history traits involved in the evolution of fecundity and the genetic changes associated with this evolution were also investigated. The results reveal that short-term evolution of increased fecundity in Qß was associated with decreased viability of phage virions. This trade-off apparently arose because fecundity increased at the expense of reducing the amount of resources (mainly time) invested per produced virion. Thus, the results also indicate that Qß fecundity may be enhanced through increases in the rates of adsorption to the host and progeny production. Finally, genomic sequencing of the evolved populations pinpointed sequences likely to be involved in the evolution of Qß fecundity.

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Hopkins, Juhani, Gautier Baudry, Ulrika Candolin, and Arja Kaitala. "I'm sexy and I glow it: female ornamentation in a nocturnal capital breeder." Biology Letters 11, no. 10 (October 2015): 20150599. http://dx.doi.org/10.1098/rsbl.2015.0599.

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In many species, males rely on sexual ornaments to attract females. Females, by contrast, rarely produce ornaments. The glow-worm ( Lampyris noctiluca ) is an exception where wingless females glow to attract males that fly in search of females. However, little is known about the factors that promote the evolution of female ornaments in a sexual selection context. Here, we investigated if the female ornament of the glow-worm is a signal of fecundity used in male mate choice. In support of this, we found brightness to correlate with female fecundity, and males to prefer brighter dummy females. Thus, the glow emitted by females is a reliable sexual signal of female fecundity. It is likely that male preference for the fecundity-indicating ornament has evolved because of large variation among females in fecundity, and because nocturnal males cannot directly assess female size and fecundity. These results indicate that female ornamentation may evolve in capital breeders (i.e. those in which stored resources are invested in reproduction) when females vary significantly in fecundity and this variation cannot be assessed directly by males.

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Coleman, Matthew T., Joanne S. Porter, and Michael C. Bell. "Investigating fecundity and egg loss using a non-invasive method during brooding in European lobster (Homarus gammarus)." ICES Journal of Marine Science 76, no. 6 (April 8, 2019): 1871–81. http://dx.doi.org/10.1093/icesjms/fsz055.

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Abstract This article examines two important components of measurement of fecundity in the European lobster Homarus gammarus: (i) comparing the traditional gravimetric dry weight fecundity method against two non-invasive depth gauge methods initially developed for Homarus americanus and (ii) utilizing the depth gauge method to determine egg loss during the brooding period and its impacts on effective fecundity estimates. No significant difference was observed between fecundity estimates derived using either the traditional or depth gauge methods. Derived fecundity estimates from the two depth gauge methods differed by −0.31% (±2.7 s.e.) for cylinder and −1.1% (±2.4 s.e.) for ellipsoid fecundity estimates compared with the traditional method. This highlights the utility of the depth gauge method for providing fast, reliable and low-cost estimates without sacrificing lobsters or their egg masses. Egg loss is estimated to be as high as 44% from initial extrusion to hatching. The application of the non-invasive methods for estimating fecundity to other fisheries and stocks is discussed along with the importance of understanding egg loss in this commercially valuable fishery.

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Poudel, Jwala, Jay Narayan Shrestha, Dipak Rajbanshi, and Jash Hang Limbu. "Fecundity of Glyptothorax telchitta (Hamilton, 1822) from Tamor River, Nepal." Our Nature 21, no. 1 (January 1, 2023): 60–66. http://dx.doi.org/10.3126/on.v21i1.50831.

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The present study assesses the fecundity of Glyptothorax telchitta, a hill stream fish from the Tamor River, Nepal. A total of 60 specimens were collected from the Tamor River, with the help of local fishermen between March 2019 and February 2020. The absolute fecundity ranged from 3385 to 14298 eggs with the mean absolute fecundity of 9448.469 ± 607.783. The fish was found to be a medium fecund fish. Relative fecundity ranged from 151 to 529 eggs per gram body weight with mean relative fecundity of 371.38 ± 15.72. Fecundity showed significant positive correlations with ovary weight (r = 0.858) total length (r = 0.844) and total weight (r = 0.825). This indicated that fecundity dependent is mostly on ovary weight. Gonado-somatic index scored the peak values during March (15.15%) and May (15.01%), indicating the fish’s spawning period during the spring season. Egg sizes varied from 0.382 mm to 1.149 mm. The appearance of various sizes of eggs in a single ovary indicated that the fish was a fractional spawner. The ovaries occupied maximum space in the abdomen during the breeding season.

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De Oliveira, J. A. A., B. A. Roel, and M. Dickey-Collas. "Investigating the use of proxies for fecundity to improve management advice for western horse mackerel Trachurus trachurus." ICES Journal of Marine Science 63, no. 1 (January 1, 2006): 25–35. http://dx.doi.org/10.1016/j.icesjms.2005.07.006.

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Abstract Observations of fecundity from the 2001 western horse mackerel spawning-stock biomass survey suggest that the species is an indeterminate spawner. Therefore, estimates of fecundity based on biological analyses and until recently used in the calibration of the stock assessment are now questioned. The stock is assessed by fitting a linked Separable and ADAPT VPA-based model to the catch-at-age data and to the egg production estimates. Currently, the assumption is that egg production and spawning-stock biomass are linked by a constant but unknown fecundity parameter, estimated within the model. In this study, the effects of introducing relationships linking biological indicators of fecundity, such as lipid content or feeding intensity during the spawning season, to actual fecundity are examined within a simulation framework. Simulations suggest that when the underlying relationships between fecundity and the proxy are poorly described, weak, or based on a relatively short time-series of data, the assumption of constant fecundity will result in better management advice than using the proxy.

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Rajkumar, M., S. Lakshmi Pillai, Josileen Jose, K. S. Sobhana, and M. Rosalind George. "Relationship fecundity – morphometrics in the green tiger shrimp, Penaeus semisulcatus De Haan, 1844 (Decapoda, Penaeidae), along the Palk Bay, southern Peninsular India." Crustaceana 96, no. 9 (September 1, 2023): 853–65. http://dx.doi.org/10.1163/15685403-bja10319.

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Abstract The green tiger shrimp, Penaeus semisulcatus, is a commercial species supporting important fishery along the Palk Bay coasts. It is a much sought-after seafood commodity influencing the livelihood of the local fishers. This study aims to investigate the fecundity of the species in relation to its morphometry. Fecundity is an index of reproductive capacity used to calculate a stock’s reproductive potential and the egg’s survival. The absolute fecundity of the shrimp ranged from 26 100 to 750 000 ova alive per female, and the mean absolute fecundity from 59 100 to 583 000 ova alive per female. The relationship between fecundity and the morphometric measurements showed a positive exponential correlation. One-way ANOVA indicated a significant difference in the different size classes’ carapace length, total weight, ovary weight, absolute fecundity, stomach weight, and gastrosomatic index. There was no significant difference between the relative fecundity and the gonadosomatic index. This study provides insight into the reproductive potential of P. semisulcatus for efficient management of the resource in Palk Bay, Tamil Nadu, India.

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Rae, G. A., and J. Calvo. "Fecundity and reproductive habits in Patagonotothen tessellata (Richardson, 1845) from the Beagle Channel, Argentina." Antarctic Science 7, no. 3 (September 1995): 235–40. http://dx.doi.org/10.1017/s0954102095000332.

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Population fecundity and reproductive habits in Patagonotothen tessellata were established for each reproductive period during 1988 and 1989. Fecundity/total length and fecundity/total weight relationships were analysed through regression models. Fecundity was positively correlated with fish length and weight. Mean fecundity was 25932 eggs (range 7634–62033). The regressions for each reproductive period are similar, suggesting that the amount of energy allocated to reproduction does not vary between spawning periods. Parental behaviour is described from both field and laboratory observations. Nesting and parental care were carried out by P. tessellata males. The life history strategy of this species is discussed in relation to that of other nototheniid species.

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Hubbs, Clark, and Doyle T. Mosier. "Fecundity of Gambusia gaigei." Copeia 1985, no. 4 (December 10, 1985): 1063. http://dx.doi.org/10.2307/1445264.

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Salzer, Elizabeth A. J. "Fecundity in transgender men." Journal of the American Academy of Physician Assistants 34, no. 10 (October 2021): 51–53. http://dx.doi.org/10.1097/01.jaa.0000750996.25261.ce.

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Memmi, Albert. "The Fecundity of Exile." Journal of French and Francophone Philosophy 19, no. 2 (December 12, 2011): 4–6. http://dx.doi.org/10.5195/jffp.2011.504.

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Chiek, Yual. "Lawful Fecundity and Incompossibility." Leibniz Society Review 26 (2016): 129–49. http://dx.doi.org/10.5840/leibniz2016266.

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Guenther, Lisa. "Fecundity and Natal Alienation." Levinas Studies 7 (2012): 1–19. http://dx.doi.org/10.5840/levinas201273.

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Zaadstra, Boukje M., Jacob C. Seidell, Paul A. H. Van Noord, Egbert R. te Velde, J. Dik F. Habbema, Baukje Vrieswijk, and Jan Karbaat. "Fat and Female Fecundity." Obstetrical & Gynecological Survey 48, no. 7 (July 1993): 484–85. http://dx.doi.org/10.1097/00006254-199307000-00022.

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38

Gemmell, Neil J., and Jon Slate. "Heterozygote Advantage for Fecundity." PLoS ONE 1, no. 1 (December 27, 2006): e125. http://dx.doi.org/10.1371/journal.pone.0000125.

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39

Skakkebaek, Niels E., Niels Jorgensen, Katharina M. Main, Ewa Rajpert-De Meyts, Henrik Leffers, Anna-Maria Andersson, Anders Juul, et al. "Is human fecundity declining?" International Journal of Andrology 29, no. 1 (February 2006): 2–11. http://dx.doi.org/10.1111/j.1365-2605.2005.00573.x.

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40

Abedon, Stephen T., and Rachel R. Culler. "Optimizing bacteriophage plaque fecundity." Journal of Theoretical Biology 249, no. 3 (December 2007): 582–92. http://dx.doi.org/10.1016/j.jtbi.2007.08.006.

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Davis, G. H. "Fecundity genes in sheep." Animal Reproduction Science 82-83 (July 2004): 247–53. http://dx.doi.org/10.1016/j.anireprosci.2004.04.001.

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Hudson, W. D. "Book Reviews : Philosophical Fecundity." Expository Times 100, no. 8 (May 1989): 316. http://dx.doi.org/10.1177/001452468910000837.

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Ghosh, Bishnupriya, and Bhaskar Sarkar. "DIASPORA AND POSTMODERN FECUNDITY." Communicare: Journal for Communication Studies in Africa 16, no. 1 (November 3, 2022): 19–48. http://dx.doi.org/10.36615/jcsa.v16i1.1897.

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Central to the experience of postmodernity is the increase in, and the intensification of, transnational encounters. The globalization of capital, culture, work-forces, and identities leads to patterns of homogenization whose totalizing tendency is undercut by intense fragmentation and the local play of differences. Thus Coca-Cola and IBM feel the need to acknowledge the heterogenity of the world market, even as they capture it. The increased productivity in economic and cultural terms marks the postmodem as remarkably fecund. This perception of fecundity comes from the various, and often opposing, groups on the pOlitical continuum.1 The 'triumph' of transnational capital in Asia and the entry of Eastern Europe into the capitalist fold have created unprecedented economic and financial flows. Simultaneously, the antifoundational dismantling of epistemological hierarchies release long-repressed energies that create new flows and open up fresh possibilities. These new flows and structurations require cognitive refigurations, as older modes of knowing the world have become inadequate. The nation is one social and cul-tural formation that has come to be rigorously Interrogated in the light of the global-local· dynamisms. A rise in the volume of migrations and the increasing visibility of varied diasporas - communities that transcend the geopolitical boundaries of the nation-state - demand a new sense of national belonging: national heritage, essence, tradition etc. have lost their immanent valences. For instance, Chow (1993) stresses the need to "unlearn Chinese ness" in order to foster Chinese diasporic identity. Our object of study is the Indian diaspora as it redefines the Indian nation. We look at specific political controversies among immigrant/expatriate Indians about what it means to be properly Indian. We trace the Indian diaspora's relation to 'home' and 'host' nations in cinematic representations originating both in and outside of India. As diasporic cultural productions are celebrated as part and parcel of the glob~1 postmodernism, we use this occasion to take a hard look at the promises of postmodern fecundity.

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Suonio, Sakari, Seppo Saarikoski, Olavi Kauhanen, Annikki Metsäpelto, Juhani Terho, and Ilkka Vohlonen. "Smoking does affect fecundity." European Journal of Obstetrics & Gynecology and Reproductive Biology 34, no. 1-2 (January 1990): 89–95. http://dx.doi.org/10.1016/0028-2243(90)90011-o.

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Kutzer, M. A. M., J. Kurtz, and S. A. O. Armitage. "Genotype and diet affect resistance, survival, and fecundity but not fecundity tolerance." Journal of Evolutionary Biology 31, no. 1 (December 4, 2017): 159–71. http://dx.doi.org/10.1111/jeb.13211.

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McQuaid, N., R. P. Briggs, and D. Roberts. "Fecundity of Nephrops norvegicus from the Irish Sea." Journal of the Marine Biological Association of the United Kingdom 89, no. 6 (April 15, 2009): 1181–88. http://dx.doi.org/10.1017/s0025315409000319.

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Potential fecundity, number of oocytes in the mature ovary, and realized fecundity, number of eggs extruded and attached to the pleopods of female Nephrops, caught at the start of the incubation period were estimated for females from the eastern and western Irish Sea grounds. Potential fecundity was found to differ significantly between eastern and western Irish Sea stocks, while realized fecundity did not differ between areas. Inter-year comparison of realized fecundity, and effective fecundity (the number of mature eggs on the pleopods of females at the end of the incubation period) in the western Irish Sea stocks revealed no significant variation over time. Egg loss during the transition from oocytes in the ovary to mature eggs increased with female size, ranging from 40% at 25 mm carapace length (CL) to 65% at 40 mm CL. No relationship was found between egg diameter or volume and female size.

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Logue, D. N., A. Gill, and T. H. McClelland. "The effect on fertility of fecundin used together with PMSG and progestagen in early lambing mule ewes." Proceedings of the British Society of Animal Production (1972) 1986 (March 1986): 32. http://dx.doi.org/10.1017/s0308229600015439.

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Observations of the effect of the immunogen ovandrotone-albumin (Fecundin ® Coopers Animal Health) when used in ewes mated in their breeding season have shown that with a boost-tupping interval (BT) of 21 days for natural oestrus and 28 days for synchronised oestrus there was an increased fecundity but that treated ewes lambed a little later than controls.While this latter effect was not dramatic it was felt advisable to investigate the use of Fecundin as a means of boosting lamb production in an early lambing flock in conjunction with progestagen and PMSG treatments.

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Maema, Malefane. "Experimental infection ofTribolium confusum(Coleoptera) byHymenolepis diminuta(Cestoda): host fecundity during infection." Parasitology 92, no. 2 (April 1986): 405–12. http://dx.doi.org/10.1017/s0031182000064167.

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SUMMARYSome effects ofHymenolepis diminutaon the fecundity ofTribolium confusumare described. Host fecundity is observed to be reduced exponentially with increasing parasite burden/host, although there are differences in the ability of individual hosts to respond to parasitism. Of particular interest is the finding that host fecundity is greatly reduced in young beetles on or by day 14 post-infection (p.i.). This age-related reduction in host fecundity is discussed in relation to the population dynamics of this hostr-parasite relationship.

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Chakraborty, Binay K., SA Azad, B. Barman, and AMO Faruque. "Fecundity and gonado somatic index of Gangetic mud eel, Monopterus cuchia (Hamilton, 1822)." Bangladesh Journal of Zoology 41, no. 2 (May 13, 2015): 165–72. http://dx.doi.org/10.3329/bjz.v41i2.23318.

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The gonado-somatic index (GSI) and fecundity of Gangetic mud eels Monopterus cuchia (Hamilton, 1822) were investigated during January to December, 2010 at Sherpur, Bangladesh. Highest GSI value was found in the month of June and the values began to fall gradually from July to December in both sexes. The fecundity ranged from 458.0±31.22 to 1116.0±11.31 in 62 samples having a total length of 54.25±1.71 to 66.05±0.71 cm, body weight from 256.33±45.14 to 492.50±2.50 g and gonad weight from 21.32±4.48 to 55.90±0.98 g. The relationships between body length and fecundity was found to be polynomial of second order of body weight and was expressed as: Y=0.2683 X2- 1.9383 X+370.72. The regression equation established for fecundity on total body weight was Y=454.37 X-692.8. The regression equation established for fecundity on total gonad weight was Y=19.602 X-27.546. The above equation showed that the relationships between fecundity and total weight was curvilinear. A highly significant (P<0.01) linear relationship was found to exist between fecundity and gonadal weight.Bangladesh J. Zool. 41(2): 165-172, 2013

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Tanasichuk, R. W., and D. M. Ware. "Influence of Interannual Variations in Winter Sea Temperature on Fecundity and Egg Size in Pacific Herring (Clupea harengus pallasi)." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 8 (August 1, 1987): 1485–95. http://dx.doi.org/10.1139/f87-178.

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Data for 2937 fish, collected from seven locations over five years, were analysed to evaluate the effects of sea temperature and stock biomass on size-specific ovary weight and fecundity at spawning. Ovary weight did not vary significantly between years or locations. Size-specific fecundity was higher in 1983, when coastal waters were abnormally warm because of a strong El Niño – Southern Oscillation event. The effect of location was equivocal: one stock that overwintered in warm water tended to have a higher fecundity. Mean sea temperature between 60 and 90 d before spawning (in spring) best accounted for variations in size-specific fecundity. Temperature may influence fecundity by regulating gonadotropin concentration and consequently pre-ovulatory atresia. We hypothesize that the trade-off between fecundity and egg size is adaptive. A theoretical analysis of the early life history of Pacific herring suggests that, to maximize survival to metamorphosis, egg size should decrease and fecundity increase with temperature when the larval growth rate Q10 is less than the mortality rate Q10. Our model seems to explain the differences in egg size between recruit and repeat spawners, and between stocks of Atlantic herring that spawn in different seasons.

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Journal articles on the topic 'Fecundity'

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