Abstract:
1. This study was conducted to determine the effects of graded levels of phytase on the performance, egg quality and gut health of white laying hens.2. Treatments consisted of a negative control (NC) diet containing 0.14% available phosphorus (avP), positive control (PC) diet containing 0.35% avP provided via dicalcium phosphate (DCP) and DCP replaced in the PC by with three graded levels of phytase derived from Komagataella phaffii at 500 (PC-500), 750 (PC-750) and 1000 (PC-1000) FTU/kg which provided 0.176%, 0.188% and 0.200% of avP, respectively.3. Egg production, feed intake, feed conversion ratio and jejunal morphometry were negatively affected in NC-fed birds (p < 0.05). Considering the whole period, birds fed a diet supplemented with graded levels of phytase shared the same egg production and feed intake levels with PC birds (p < 0.05). Feed conversion ratio was significantly lowered by 4.9%, 1.6% and 7.6% in hens fed on diets PC-500, PC-750 and PC-1000, respectively compared to those fed the PC (p < 0.05).4. Neither of the dietary treatments affected cracked eggs, dirty eggs, eggshell breaking strength and eggshell thickness. Dietary supplementation of phytase significantly increased villus surface area by 15%, 36% and 40% in PC-500, PC-750 and PC-1000 birds, respectively compared to PC (p < 0.05).5. A significant increase in lactobacillus count was observed in line with increasing the level of phytase (p < 0.05). Dietary treatments had no effect on the caecal coliform or aerobic populations. Furthermore, phytase supplementation significantly increased the concentrations of total caecal short-chain fatty acid (SCFA; p < 0.01).6. In conclusion, along with improving performance parameters, the inclusion of phytase in laying hen diets can ameliorate intestinal morphology and stimulate caecal microflora and increase SCFA concentrations.
摘要:
1.这项研究是为了确定植酸酶的分级水平对性能的影响,白蛋鸡的蛋品质和肠道健康2.治疗包括含有0.14%有效磷(avP)的阴性对照(NC)饮食,阳性对照(PC)饮食中含有0.35%的avP,通过磷酸二钙(DCP)和DCP在PC中被三个分级水平的植酸酶所替代,这些植酸酶来自于500(PC-500)的Komagataellaphafii,750(PC-750)和1000(PC-1000)FTU/kg,提供0.176%,AVP的0.188%和0.200%,分别.3.鸡蛋生产,饲料摄入量,在NC喂养的鸟类中,饲料转化率和空肠形态计量学受到负面影响(p<0.05)。考虑到整个时期,饲喂添加分级水平植酸酶的日粮的禽类与PC禽类具有相同的产蛋量和采食量(p<0.05)。饲料转化率显著降低4.9%,与饲喂PC的母鸡相比,饲喂PC-500,PC-750和PC-1000的母鸡分别为1.6%和7.6%(p<0.05)。两种饮食处理都不影响破裂的鸡蛋,脏鸡蛋,蛋壳断裂强度和蛋壳厚度。日粮补充植酸酶使绒毛表面积显著增加15%,36%和40%在PC-500,PC-750和PC-1000鸟,分别与PC相比(p<0.05)。观察到乳杆菌计数的显著增加与植酸酶水平的增加一致(p<0.05)。饮食治疗对盲肠大肠杆菌或有氧人群没有影响。此外,植酸酶显著提高了盲肠总短链脂肪酸浓度(SCFA;p<0.01)。总之,随着性能参数的改善,在蛋鸡日粮中加入植酸酶可以改善肠道形态,刺激盲肠微生物区系并增加SCFA浓度。