The objective of this study was to evaluate the effect of milking hygiene practices, herd size, water hardness, and temperature-humidity index (THI) on the physicochemical and microbiological characteristics of raw milk, and standard plate count (SPC) in milking machines of dairy farms in the central region of Mexico. Data were collected from fifty-three dairy farms during one year. The evaluated effects included milking hygiene conditions (good, medium, poor), herd size (1-50, 51-100, 101-150, ≥151 heads), water hardness (soft or [...] ABSTRACT The objective of this study was to evaluate the effect of milking hygiene practices, herd size, water hardness, and temperature-humidity index (THI) on the physicochemical and microbiological characteristics of raw milk, and standard plate count (SPC) in milking machines of dairy farms in the central region of Mexico. Data were collected from fifty-three dairy farms during one year. The evaluated effects included milking hygiene conditions (good, medium, poor), herd size (1-50, 51-100, 101-150, ≥151 heads), water hardness (soft or

In a performance trial, 50 intact Rambouillet×Dorper male lambs (19±2.8 kg), were randomly assigned to experimental diets containing 0, 10, 20, 30 or 40%, Opuntia leucotrichia (O. leucotrichia; dry matter basis). At day 91 animals were slaughtered for carcass and meat quality evaluation. In trial two, five ruminal cannulated Rambouillet male rams were used in a digestion study. Dry matter intake, average daily gain and feed efficiency of lambs decreased (P<0.05) generally with increasing levels of O. leucotrichia. Carcass dressing was increasing as O. leucotrichia was augmented. Water intake decreased as consumption of O. leucotrichia increased. Crude protein was digested higher (P<0.05) in lambs fed 40% diet than other lambs. Ruminal pH and ammonia-N were not significantly different among treatments. Inclusion of O. leucotrichia on feedlot lamb diets is a good option for production systems if this resource is available.

This study aimed to evaluate the effect of three inclusion levels of Opuntia ficus-indica mucilage (OFM) to the lactose-egg yolk extender on the quality of frozen-thawed boar semen. Semen samples (n=22) were split into four OFM treatments: 0.0 (control), 3.3, 6.7, or 10.0% OFM. The semen was packaged in 0.5 mL straws and frozen using conventional methods. The sperm motility, viability, membrane integrity (HOST), and morphology (intact acrosome and normal sperm) characteristics were evaluated immediately post-thaw. Additionally, sperm were incubated at 37 ºC during 3.5 h and monitored hourly in a termoresistance test (TRT) to assess sperm motility, viability, and membrane integrity, The study showed that adding OFM to the freezing extender significantly improved (P < 0.05) sperm quality characteristics, without affecting (P > 0.05) acrosome integrity or sperm abnormalities. Furthermore, the OFM addition improved (P < 0.05) the sperm viability and membrane integrity for up to 3.5 h of incubation. Results indicate that OFM can be added to the extender at a 6.7% OFM inclusion level to improve the quality of cryopreserved boar sperm.

One hundred eighty-nine Catalan crossbreed donkeys (Equus africanus asinus) were used to evaluate the effect of gender (gelding, n=106; or female, n=83) and live weight at slaughter (LW) (kg, n=37) on carcass characteristics, non-carcass components and meat and fat color. Geldings had greater (P<0.05) carcass weight, carcass dressing and ^*L value of subcutaneous fat than females; but females had greater (P<0.05) cooling loss, a^* value of semitendinosus muscle and b^* value of subcutaneous fat. Donkeys with more than 126kg of LW showed greater (P<0.05) carcass weight and dressing and lower (P151kg). Meanwhile, the LW did not affect the color (L^*, a^* and b^* values) of subcutaneous fat (P>0.05). These results suggested that both gender and live weight should be considered when producing meat from donkeys. It is advisable to use geldings weighing more than 126kg at slaughter to obtain the greatest weight and carcass yield.

The nutritional potential of Opuntia forage is limited by its low crude protein (CP) content. Urea supplementation enhances low-quality forages, but its application in Opuntia silage and its influence on ruminal degradability are limited. This study evaluated the effects of urea addition (0, 20, 40, 60, or 80 g/kg of dry matter (DM)) and ensiling duration (0, 4, 8, 16, 24, or 28 d) on the silage pH and in situ DM degradability of four Opuntia species. Silage pH was influenced by both species and urea level, with greater values observed in silages treated with urea at 80 g/kg DM. The effective degradability of DM (EDDM) was influenced by Opuntia species and was reduced at the highest urea level. In contrast, the ensiling period beyond 12 d did not affect EDDM, and pH stabilized for all treatments after this point. Urea supplementation increases CP content and modifies silage pH but does not improve ruminal degradability. It is recommended that the addition of urea in Opuntia silages should not exceed 60 g/kg DM to avoid reduced fermentative quality. A study limitation is the absence of fermentation end-product data, which would offer a more complete quality assessment.