El-Zaiat Hani M, Al-Marzooqi Waleed, Al-Kharousi Kaadhia
Department of Animal and Veterinary Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
J Anim Physiol Anim Nutr (Berl). 2025 Mar;109(2):338-349. doi: 10.1111/jpn.14057. Epub 2024 Oct 11.
Recently, the potential of using chitosan (CHI) as a feed additive to enhance ruminal fermentation and improve animal performance has gained increasing attention in ruminant nutrition. This study was undertaken to investigate the effect of dietary supplementation with increasing doses of CHI on rumen fermentation attributes and microbial composition, digestibility and milk performance in Dhofari goats. Twenty-four lactating goats (27 ± 1.8 kg of initial live body weight) were fed a control diet comprising of Rhodes grass hay plus a concentrate feed mixture. Goats were assigned to one of three experimental treatments (n = 8 per treatment) as: (1) control diet with no supplement (CTRL), (2) control diet with 0.300 g/day CHI (CHI0.3) and (3) control diet supplemented with 0.600 g/day CHI (CHI0.6) for a 45-day experimental period. Dietary supplementation with increasing doses of CHI decreased (p < 0.05) linearly ruminal pH (p = 0.023), total short chain fatty acids concentrations (p = 0.011), acetate (p = 0.013) and butyrate (p = 0.042) proportions, acetate to propionate ratio (p < 0.001), estimated methane (CH) production (p < 0.001), ammonia nitrogen concentrations (p = 0.003) and protozoa abundance (p = 0.003). However, the ruminal propionate proportion augmented (p = 0.002) linearly with increasing doses of CHI in the diet. Increasing doses of CHI linearly increased the abundance of the ruminal propionate-producing bacteria, while diminished acetate and CH-producing bacteria (p < 0.05). Serum total protein (p = 0.037) and glucose (p = 0.042) levels linearly increased as CHI doses increased in the diet. However, serum UREA levels decreased linearly (p = 0.002) by 21% with increasing CHI amounts in the diet. The digestibility of organic matter, crude protein and neutral detergent fibre increased linearly with the increasing CHI doses (p < 0.05). Neither linear nor quadratic responses (p > 0.05) were observed in daily milk yield and feed efficiency by supplementing the diet with CHI. In conclusion, supplementing the diet with CHI at a dose of 0.600 g/day as a feed additive for dairy goats reduced estimated CH generation and improved fibre and protein digestion, with no influence on feed intake, milk yield or composition.
最近，壳聚糖（CHI）作为一种饲料添加剂来增强瘤胃发酵和改善动物生产性能的潜力在反刍动物营养领域受到了越来越多的关注。本研究旨在调查在佐法尔山羊日粮中添加不同剂量CHI对瘤胃发酵特性、微生物组成、消化率和产奶性能的影响。24只泌乳山羊（初始体重27±1.8千克）饲喂由罗得草干草加精饲料混合物组成的对照日粮。山羊被分配到三种试验处理之一（每个处理n = 8）：（1）不添加任何物质的对照日粮（CTRL），（2）添加0.300克/天CHI的对照日粮（CHI0.3），（3）添加0.600克/天CHI的对照日粮（CHI0.6），试验期为45天。日粮中添加不同剂量的CHI使瘤胃pH值（p = 0.023）、总短链脂肪酸浓度（p = 0.011）、乙酸盐（p = 0.013）和丁酸盐（p = 0.042）比例、乙酸盐与丙酸盐比例（p < 0.001）、估计的甲烷（CH）产量（p < 0.001）、氨氮浓度（p = 0.003）和原虫数量（p = 0.003）呈线性下降（p < 0.05）。然而，日粮中随着CHI剂量增加，瘤胃丙酸盐比例呈线性增加（p = 0.002）。CHI剂量增加使瘤胃中产生丙酸盐的细菌数量呈线性增加，而产生乙酸盐和CH的细菌数量减少（p < 0.05）。随着日粮中CHI剂量增加，血清总蛋白（p = 0.037）和葡萄糖（p = 0.042）水平呈线性增加。然而，随着日粮中CHI含量增加，血清尿素水平呈线性下降（p = 0.002），下降了21%。随着CHI剂量增加，有机物、粗蛋白和中性洗涤纤维的消化率呈线性增加（p < 0.05）。日粮中添加CHI后，日产奶量和饲料效率未观察到线性或二次反应（p > 0.05）。总之，日粮中添加0.600克/天的CHI作为奶山羊的饲料添加剂可减少估计的CH生成，提高纤维和蛋白质消化率，且对采食量、产奶量或组成无影响。
