Yoo Seung Bin, Song Yoon Soo, Seo Siyoung, Kim Beob Gyun
Department of Animal Science, Konkuk University, Seoul 05029, Republic of Korea.
Animal Environmental Division, National Institute of Animal Science, Wanju 55365, Republic of Korea.
Animals (Basel). 2023 Dec 25;14(1):82. doi: 10.3390/ani14010082.
The objective was to evaluate the effects of benzoic acid, bromelain, adipic acid, and humic substance supplementation on nitrogen balance, urinary pH, slurry pH, and manure odorous compounds in pigs. Fifteen castrated male pigs with an initial body weight of 37.9 kg (standard deviation = 4.1) were individually housed in metabolism crates. The animals were allocated to a triplicated 5 × 2 incomplete Latin square design with 15 animals, 5 experimental diets, and 2 periods. The basal diet mainly consisted of corn, soybean meal, and rapeseed meal. Four experimental diets were prepared by supplementing each additive at a concentration of 10 g/kg at the expense of corn starch to the basal diet. Each period consisted of a 4-day adaptation period, a 24 h collection period for slurry sampling, and a 4-day collection period for feces and urine. The feces and urine collected for 24 h on day 5 were mixed at a ratio of fecal weight and urine weight to obtain slurry samples. The apparent total tract digestibility N in pigs fed the humic substance diet was the least ( < 0.05) compared to the other groups. The daily retained N and N retention as % ingested tended ( < 0.10) to be the lowest in the adipic acid group among the treatments. The urinary pH in pigs fed the adipic acid diet was less ( < 0.05) than that in other groups except the benzoic acid group. The slurry pH tended to differ among the treatment groups ( = 0.074) with the lowest value in the pigs fed the adipic acid diet. The concentrations of indole in slurry ( = 0.084) and isovalerate in feces ( = 0.062) tended to differ among the groups with the lowest values in the pigs fed the humic substance diet. In conclusion, adipic acid supplementation in pig diets can decrease urinary pH and slurry pH. Although benzoic acid and adipic acid have limited effects in reducing odorous compounds, humic substances have the potential to reduce some odorous compounds.
本研究旨在评估补充苯甲酸、菠萝蛋白酶、己二酸和腐殖质对猪的氮平衡、尿液pH值、粪浆pH值和粪便气味化合物的影响。15头初始体重为37.9千克（标准差 = 4.1）的去势公猪被单独饲养在代谢笼中。这些动物被分配到一个重复的5×2不完全拉丁方设计中，共有15只动物、5种实验日粮和2个阶段。基础日粮主要由玉米、豆粕和菜粕组成。通过以玉米淀粉为代价，在基础日粮中添加浓度为10克/千克的每种添加剂，制备了四种实验日粮。每个阶段包括一个4天的适应期、一个用于粪浆采样的24小时收集期以及一个用于粪便和尿液的4天收集期。在第5天收集的24小时粪便和尿液按粪便重量与尿液重量的比例混合，以获得粪浆样本。与其他组相比，饲喂腐殖质日粮的猪的表观全肠道氮消化率最低（<0.05）。在各处理组中，己二酸组的每日氮潴留量和氮潴留占摄入量的百分比趋于最低（<0.10）。饲喂己二酸日粮的猪的尿液pH值低于除苯甲酸组外的其他组（<0.05）。各处理组之间的粪浆pH值存在差异趋势（P = 0.074），饲喂己二酸日粮的猪的粪浆pH值最低。粪浆中吲哚的浓度（P = 0.084）和粪便中异戊酸的浓度（P = 0.062）在各组之间存在差异趋势，饲喂腐殖质日粮的猪的这些值最低。总之，在猪日粮中添加己二酸可降低尿液pH值和粪浆pH值。虽然苯甲酸和己二酸在减少气味化合物方面作用有限，但腐殖质有潜力减少一些气味化合物。
