Litter size and progeny birth weights are lower in gilts than in sows. Somatotropin (ST) is an important regulator of ovulation, fetal growth and survival. We therefore investigated effects of pST treatment of gilts for two to four weeks before mating on ovulation rate, behavioural estrus, fetal growth and survival, litter size and birth weights. In Experiment One, gilts were injected with 0, 30, 60 or 90 µg pST/kg/day for 14 days commencing 7 days after first estrus. Reproductive tracts were collected and corpora lutea and follicle numbers counted 5.5 days after second estrus. Ovulation rate (P=0.031) and number of medium-sized follicles (P=0.059) correlated positively with pST dose. In Experiment Two, gilts were injected with 0, 12.5, 25 or 50 µg pST/kg/day for 21 days from first estrus, and mated at second estrus. Numbers of corpora lutea, follicles and fetuses were counted at day 31 of pregnancy. Numbers of medium follicles and ovary weights were positively related to pST dose. In Experiment Three, 31 week old (1(st) replicate) or 27 week old (2(nd) replicate) gilts were injected daily with 0 or 12.5 µg pST/kg/day until mating 25.9 ± 0.6 days later, and delivered at term. Pre-mating pST increased total litter size in younger gilts in the 2(nd) replicate only (P<0.05). In conclusion, injecting gilts with pST before mating does not consistently alter ovulation rate, increases the number of medium follicles available for recruitment at the second mating after treatment and increases subsequent litter size in younger gilts.
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Ecol Evol
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Department of Zoology, Fisheries, Hydrobiology and Apiculture, Faculty of Agronomy Mendel University in Brno Brno Czech Republic.
This study evaluates the response of ground beetle (Coleoptera: Carabidae) assemblage to forest management practices by integrating species composition, body traits, wing morphology and developmental instability. Traditional approaches that rely on averaged identity-based descriptors often overlook phenotypic plasticity and functional trait variability, potentially masking species-specific responses to environmental changes. To address this, we applied a three-layered analytical approach to address this gap, utilising ground beetle occurrence and morphological trait data from Podyjí National Park, Czech Republic.
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Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
Solid lipid nanoparticles (SLNs) have gained interest as drug delivery carriers due to their efficient cellular internalization and increased therapeutic effect of the loaded drug, with minimal side effects. Although recently several studies have shown the possibility to administer SLNs during pregnancy to vehicle mRNA to the placenta, data about the effect of premating exposure to SLNs on pregnancy outcome are scant. Considering that assumption of drug-delivering nanocarriers in reproductive age may potentially affect women's reproductive health, the aim of the present study was to evaluate whether repeated oral administration of SLNs to female mice prior to mating would influence key pregnancy outcomes.
View Article and Find Full Text PDFJ Dev Orig Health Dis
January 2025
Postgraduate Program in Physiological Sciences, State University of Londrina, Londrina, Parana, Brazil.
Nutritional status during the developmental periods leads to predisposition to several diseases and comorbidities, highlighting metabolic and reproductive changes throughout adult life, and in the next generations. One of the experimental models used to induce undernutrition is litter size expansion, which decreases the availability of breast milk to pups and delays development. This work evaluated the effects of maternal undernutrition induced by litter size expansion, a maternal undernutrition preconception model, on the metabolic and reproductive alterations of the offspring.
View Article and Find Full Text PDFSci Rep
January 2025
Key Laboratory of Genetics, Breeding and Reproduction of Grass-Feeding Livestock, Key Laboratory of Animal Biotechnology of Xinjiang, Ministry of Agriculture(MOA), Urumqi, 830026, Xinjiang, China.
CRISPR/Cas9 technology has been widely utilized to enhance productive performance, increase disease resistance and generate medical models in livestock. The FecB allele in sheep is a mutation in the BMPRIB gene, recognized as the first major gene responsible for the high fecundity trait in sheep, leading to an increased ovulation rate in ewe. In this study, we employed CRISPR/Cas9-mediated homologous-directed repair (HDR) to introduce a defined point mutation (c.
View Article and Find Full Text PDFEndocrinology
January 2025
Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, UT, USA.
We created the c.1286C>G stop-gain mutation found in a family with primary ovarian insufficiency (POI) at age 30 years. The Eif4enif1 C57/Bl6 transgenic mouse model contained a floxed exon 10-19 cassette with a conditional knock-in cassette containing the c.
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