Epididymal bull sperm selection by Percoll® density-gradient centrifugation prior to conventional or ultra-rapid freezing enhances post-thaw sperm quality.

This study evaluated the effectiveness of Percoll® density gradient centrifugation (Percoll-DGC) for selecting bull epididymal sperm prior to conventional slow (CS) or ultra-rapid (UR) freezing and its effects on sperm quality. Fifteen pooled samples from 30 epididymides (2 different samples/pool) of 15 bulls were split into two aliquots assigned to either CS or UR freezing. Samples were either selected using Percoll-DGC (40/80 %) or left non-selected (control), resulting in four pre-freezing treatments: Percoll-CS, Control-CS, Percoll-UR, and Control-UR.

Moon cycle influences calving frequency, gestation length and calf weight at birth, but not offspring sex proportion in tropical crossbred cattle.

Numerous studies have shown the influence of the moon cycle on biological functions in farm animals, suggesting that predicting calving distribution could enhance survival rates by improving management practices in animal production. This study builds on previous research by examining the impact of the lunar cycle on calving frequency, gestation length, birth weight, and calf sex in artificially inseminated cows. We analyzed 121,276 records from dual-purpose crossbred cows across 36 farms along the western margin of Lake Maracaibo basin, Venezuela.

The moon cycle influences reproductive and productive traits in guinea pigs () from a tropical Andean area.

There is currently innumerable evidence showing that the lunar cycle affects various reproductive aspects in farm animals. However, there is very little information on the effect of the lunar cycle on productive traits in these species. A retrospective study was conducted (2015-2018) to evaluate the influence of the lunar cycle on some reproductive and productive traits in a guinea pig () production system in the southern Andean region of Ecuador.

Egg Yolk-Supplemented Tris-Citric Acid Extender Improves the Prefreezing and Post-Thaw Sperm Quality Indices of Guinea Pig () Epididymal Spermatozoa.

This study aimed to assess the suitability of egg yolk (EY) supplementation to a tris-citric acid-based extender on cryosurvival of guinea pig () epididymal spermatozoa. Two synthetic-based extenders, tris-citric acid-glucose plus 20% EY (TCG-EY) and tris-citric acid-fructose (TCF) both with 5% glycerol, were compared. Thirty-two epididymides were recovered from 16 adult guinea pig males by gonadectomy, and then the sperm samples were retrieved by retrograde flushing using TCG-EY and TCF extenders for left or right epididymis, respectively.