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Aline Fernanda Lopes Paschoal Ana Paula Gonçalves Mellagi Cristina Vicenti Ferrari Karine Ludwig Takeuti Gabriela da Silva Oliveira Mari Lourdes Bernardi Rafael da Rosa Ulguim Fernando Pandolfo Bortolozzo 《Reproduction in domestic animals》2021,56(6):897-904
Semen collection has an essential role in the initial bacterial load in boar ejaculates and extended semen. The study aimed to explore the efficacy of an adjusted penis fixation in a semi-automatic collection system on reducing bacterial contamination of ejaculates in two-boar studs with different scenarios. Historically, stud A had low levels of bacterial load in raw semen, while stud B had a high level of contamination. A total of 56 mature boars had their semen collected using two methods of penis fixation: (a) Traditional: The penis was fixed directly with the artificial cervix and transferred to the adjustable clamp; (b) Adjusted: The fixation was performed with one gloved-hand, and after exteriorization, the penis was gripped using the artificial cervix with the other gloved-hand and transferred to the adjustable clamp. The bacterial load (p = .0045) and the occurrence of ejaculates >231 CFU/ml (p = .0101) were reduced in the Adjusted compared to the Traditional method. Bacterial load was reduced when using the Adjusted method in stud B (p = .0011), which showed a greater occurrence of critical factors for bacterial contamination (p ≤ .0034). The Adjusted method reduced the occurrence of ejaculates >231 CFU/ml when the preputial ostium was dirty (p = .016) and the duration of semen collection was >7 min (p = .022) compared to the Traditional method. In conclusion, the Adjusted penis fixation was efficient in reducing bacterial load of ejaculates, mainly in boar stud B, which had high contamination challenges. 相似文献
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Selection for body weight at 49 day of age ( s and h , downward selected lines; s' and h' , upward selected lines) affected reproductive traits in CF1 mice lines. The objective of this study was to compare ovarian structures in females of these lines, as well as in unselected controls (Line t ). The number of ovarian follicles ( N ), follicle diameter (FD), number of corpora lutea (CL), litter size (LS), and body weight ( W ), were recorded. There were significant differences among lines for N , FD, CL, LS and W ; means values for the lines with the greatest difference for post-pubertal females were: N s = 19.3 and N s' = 32.7; FD h' = 161.7 and FD s' = 178.2; CL h = 10.3 and CL s' = 21.9; LS s = 6.0 and LS h' = 11.1; W h = 18.9 and W s' = 32.4. There were also differences between positive lines; Line s' had a higher proportion of large follicles in pre-pubertal females, a greater capacity to convert these follicles into CL, but a lower capacity to maintain embryos until term than Line h' . For negative lines, Line h apparently had a reduced incidence of embryonic loss when compared with Line s . In conclusion, selection for body weight modified ovarian structure, as well as reproductive efficiency. 相似文献
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Faccin J. E. G. Laskoski F. Quirino M. Gonçalves M. A. D. Mallmann A. L. Orlando U. A. D. Mellagi A. P. G. Bernardi M. L. Ulguim R. R. Bortolozzo F. P. 《Tropical animal health and production》2020,52(3):1073-1079
Tropical Animal Health and Production - Housing nursery pigs according to body weight is an observed common practice in production systems and, supposedly, improves growth performance and reduces... 相似文献
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Valetti Lucio Lima Nelson Bernardi Cazón Luis I. Crociara Clara Ortega Leandro Pastor Silvina 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):923-935
European Journal of Plant Pathology - Apple valsa canker, caused by the fungus Valsa ceratosperma, is one of the most destructive diseases of this crop. Conventional fungicide treatments are not... 相似文献