Motta Guilherme Augusto, Neto Paulo Sabino Milhomen, Nociti Ricardo Perecin, Santana Áureo Evangelista
Department of Veterinary Clinic and Surgery, School of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal 14884-900, São Paulo, Brazil.
Department of Veterinary Medicine, Araraquara University-UNIARA, Araraquara 14801-340, São Paulo, Brazil.
Animals (Basel). 2023 Jul 25;13(15):2398. doi: 10.3390/ani13152398.
The Brazilian savannah region, characterized by high average temperatures, well-defined rainy and dry seasons, soil with low productive potential, and high pressure for parasitic diseases, is home to the highest percentage of the beef herd, which is the world's largest commercial beef producer. Therefore, breeds that present rusticity combined with productivity are the focus of research in cattle breeding in the region. Considering their geographic particularities and their effects on the animals' blood parameters, the objective was to study the behavior of hematological variables, serum biochemistry, and acute phase proteins in beef calves at weaning age. Jugular blood samples were collected in a single day from 30 weaning calves (about eight months old and 200 kg of body weight) from the following breeds: Nellore, Senepol, Nellore × Aberdeen Angus cross, Nellore × Senepol cross, and Nellore × Aberdeen Angus × Senepol cross. Hematological data were obtained using an automatic cell counter, serum biochemical measurements were obtained using commercial kits, and the electrophoretogram was obtained using the SDS-page technique. In general, the results were consistent with data already published in similar situations regarding health status, age, and level of metabolic activity. However, differences observed between groups can be explained by differences observed in other concurrent variables like temperament. The pure zebu breed was more reactive than pure taurine. While crossbreds showed intermediate values, and parasitic infestation, the pure taurine breed with higher parasite infestation, while the zebu breed had lower values, which produced effects in some laboratory tests, and generated differences between breeds. In conclusion, the reference intervals available for healthy animals can be routinely used without interference from the geographic region for animals produced without nutritional failures as long as changes are recorded in pathological, infectious, metabolic, or nutritional deficiency situations. However, it is suggested that a study covering a larger number of herds may demonstrate a greater geographic effect on the studied variables.
巴西热带稀树草原地区平均气温较高，雨季和旱季分明，土壤生产潜力低，寄生虫病压力大，是牛肉牛群比例最高的地区，巴西也是世界上最大的商业牛肉生产国。因此，兼具适应性和生产力的品种是该地区养牛业育种研究的重点。考虑到该地区的地理特殊性及其对动物血液参数的影响，本研究旨在探讨断奶期肉牛犊血液学变量、血清生化指标和急性期蛋白的变化规律。在同一天从30头断奶犊牛（约8月龄，体重200 kg）采集颈静脉血样，这些犊牛来自以下品种：内洛尔牛、塞内波尔牛、内洛尔牛×阿伯丁安格斯牛杂交种、内洛尔牛×塞内波尔牛杂交种以及内洛尔牛×阿伯丁安格斯牛×塞内波尔牛杂交种。血液学数据通过自动血细胞计数器获得，血清生化指标通过商业试剂盒检测，电泳图谱采用SDS - 聚丙烯酰胺凝胶电泳技术获得。总体而言，研究结果与已发表的关于健康状况、年龄和代谢活动水平相似情况下的数据一致。然而，不同组之间观察到的差异可以用其他同时存在的变量（如性情）的差异来解释。纯瘤牛品种比纯黄牛品种反应性更强。杂交种表现出中间值，寄生虫感染方面，纯黄牛品种寄生虫感染率较高，而瘤牛品种感染率较低，这在一些实验室检测中产生了影响，并导致品种间出现差异。总之，只要在病理、感染、代谢或营养缺乏情况下记录了变化，那么对于没有营养问题的动物，健康动物的参考区间可常规使用，不受地理区域干扰。然而，建议开展一项涵盖更多牛群的研究，可能会显示出地理因素对所研究变量有更大影响。
