Sow Fafa, Niang Khady, Camara Younouss, Traoré El Hadji, Moula Nassim, Cabaraux Jean François, Missohou Ayao, Hornick Jean-Luc
Department of Animal Resources Management and Nutrition Unit, Faculty of Veterinary Medicine, University of Liège, Quartier Vallée 2, Avenue de Cureghem 6, B43a, 4000 Liège, Belgium.
Senegalese Institute for Agricultural Research (ISRA), Bel Air, Routes des Hydrocarbures, BP 3120 Dakar, Senegal.
Animals (Basel). 2020 May 15;10(5):861. doi: 10.3390/ani10050861.
This study aimed to compare digestive and metabolic characteristics in Sahelian (S) and Majorera (M) goat breeds. Six lactating females from each breed, with an average weight 27.0 ± 1.93 and 23.7 ± 1.27 kg, respectively, were used. Cowpea hay, variety 58/74, was offered as sole feed ingredient, at a rate of 2 kg of fresh matter per animal per day. The animals were placed in metabolic cages and a digestibility test was conducted according to an adaptation period of 15 days and a collection period of 7 days. The daily chemical components offered and refused and recovered faeces, urine and milk were measured in order to assess energy and nitrogen utilization. The M and S goats had similar levels of dry matter (DM) intake as well as nutrient digestibility. On a metabolic weight basis, dry matter intake, gross energy intake, metabolizable and energy intake, digestible energy and energy lost as methane production were significantly higher ( < 0.01) in M than in S goats. Urinary energy excretion was similar ( = 0.9) between breeds, while faecal energy output was higher in M than in S goats. The milk energy output from the M goats was higher than that the S goats ( < 0.05). However, metabolizable to net energy conversion efficiency (klm) was not affected by breed ( = 0.37), while N intake, milk N yield and faecal N losses, relative to metabolic weight, were significantly higher ( < 0.05) in M than in S goats. Similarly, the percentage of dietary N intake excreted in urine (UNIN) was higher in S than in M breeds. The breed factor had no effect on N retained, N digestibility, urinary N and N use efficiency. In conclusion, the M and S goats were similar in terms of energy and nitrogen use efficiency, despite higher daily milk production and DM consumption in the M goat. This suggests that the M breed is possibly more dependent on a dense nutrition diet than the S breed but requires less maintenance nitrogen.
本研究旨在比较萨赫勒山羊（S）和马约雷拉山羊（M）品种的消化和代谢特征。使用了来自每个品种的6只泌乳母羊，平均体重分别为27.0±1.93千克和23.7±1.27千克。提供豇豆干草58/74品种作为唯一的饲料成分，每只动物每天的新鲜物质摄入量为2千克。将动物置于代谢笼中，并根据15天的适应期和7天的收集期进行消化率测试。测量每日提供、拒绝和回收的粪便、尿液和牛奶的化学成分，以评估能量和氮的利用情况。M和S山羊的干物质（DM）摄入量以及养分消化率水平相似。以代谢体重为基础，M山羊的干物质摄入量、总能摄入量、可代谢能量摄入量、消化能以及作为甲烷产生而损失的能量均显著高于（<0.01）S山羊。品种间尿能排泄相似（=0.9），而M山羊的粪能输出高于S山羊。M山羊的乳能输出高于S山羊（<0.05）。然而，可代谢能量向净能量的转化效率（klm）不受品种影响（=0.37），而相对于代谢体重，M山羊的氮摄入量、乳氮产量和粪氮损失显著高于（<0.05）S山羊。同样，S品种尿液中排泄的日粮氮摄入量百分比（UNIN）高于M品种。品种因素对氮保留、氮消化率、尿氮和氮利用效率没有影响。总之，尽管M山羊的日产奶量和DM消耗量较高，但M和S山羊在能量和氮利用效率方面相似。这表明M品种可能比S品种更依赖于高营养密度的日粮，但所需维持氮较少。
