一针注射疗法可减少猪群的应激,增加畜牧场的收益

毫无疑问,应激是影响肉食品动物生产一个重要因素。处于应激的动物对疾病更敏感,生产低质量的肉类产品,生长速度和生产性能很可能达不到其正常的指标。避免非必要的应激并不是仅仅对动物福利有利:它也能确保养猪场取得良好的商业利润。     

Anthropogenic landscapes support fewer rare bee species

Landscape Ecology - The response of rare species to human land use is poorly known because rarity is difficult to study; however, it is also important because rare species compose most of...     

Digestion of soybean meal proteinin the equine small and large intestine at various levels of intake

Four mature pony geldings weighing an average of 134 kg and fitted with ileal cannulas were used in a 4×4 Latin square experiment to determine the digestibility of soybean meal (SBM) protein in different segments of the equine digestive tract at various levels of protein intake. A complete basal corn-based diet was supplemented with SBM to formulate four diets with increasing crude protein. The diets, labeled A (basal), B, C and D, contained 4.9%, 9.5%, 14% and 16.5% crude protein (as fed), and provided nitrogen, per feeding, at approximately 44.8, 84.3, 123.9 and 146.3 mg/kg of body weight, respectively. Chromic oxide was fed to measure ileal flow and fecal excretion. Digestion and absorption of nitrogen was determined from changes in nitrogen: chromium ratios, and true digestion of nitrogen was computed by regression analysis. True total tract digestion of nitrogen was 95.7%. True digestibility of nitrogen in the small intestine over the range of linearity was 72.2%, while true digestibility of nitrogen reaching the large intestine was 89.8%. These data indicate that the protein in SBM was almost completely digested in the equine digestive tract. Furthermore, approximately 75% of the digestible protein was digested prececally when nitrogen intake was less than approximately 125 mg/kg of body weight per feeding.