早期断奶和育肥期饲粮NDF水平对湖羊生长性能和消化代谢的影响

doi:10.3864/j.issn.0578-1752.2021.10.017

摘要/Abstract

摘要：

【目的】以湖羊公羔为试验对象,探究早期断奶补饲和育肥前、后期饲粮NDF水平对羔羊生长发育和消化性能的持续影响,计算试验因素间的叠加效应,筛选出最佳的组合饲养方式。【方法】选取体重[ (8.26±2.14) kg]、日龄[(20±2) d]接近的健康湖羊公羔120只,随机分为4组,每组6个重复,每重复5只;饲粮NDF水平设置:育肥前期低（33%）高（38%）水平,育肥后期低（28%）高（33%）水平。4组处理分别为:早期断奶+育肥前低NDF饲粮+育肥后低NDF饲粮（EW-LL）;早期断奶+育肥前期低NDF饲粮+育肥后期高NDF饲粮（EW-LH）;早期断奶+育肥前期高NDF饲粮+育肥后期高NDF饲粮（EW-HH）;随母哺乳+育肥期前高NDF饲粮+育肥期后期高NDF饲粮（ER-HH）。早期断奶羔羊在20日龄由随母哺乳逐渐过渡到饲喂代乳粉,同时补饲开食料,所有试验羔羊育肥周期为61-180日龄。试验期160 d。测定羔羊不同阶段体重和采食量,在羔羊2、4、6月龄进行消化代谢试验。【结果】1）4组羔羊全期体重无显著差异（P>0.05）,除46—65日龄,其余各阶段各组间日增重无显著差异（P>0.05）。2）早期断奶羔羊21—65日龄干物质采食量显著高于随母哺乳羔羊（P<0.05）,早期断奶组中,育肥前后期均采食低NDF水平饲粮的羔羊121—180日龄时颗粒料采食量显著高于其他两组（P<0.05）。3）早期断奶组羔羊哺乳期营养物质消化率及能氮利用率低于随母哺乳组。进入育肥期后,消化代谢能力优势转移,育肥前期低NDF组羔羊干物质、有机物消化率显著高于高NDF组（P<0.05）,叠加效应分析EW-LL组全期日增重增效最高,但早期断奶和育肥前期饲喂低NDF饲粮这两种饲喂方式的叠加效果为-50.57%。【结论】从整个育肥周期来看,早期断奶补饲代乳粉对羔羊生长性能有促进作用,育肥前期低NDF水平饲粮育肥效果相比高NDF水平效果较差;而育肥后期试验羔羊饲粮相同时,育肥前期饲喂低NDF饲粮的羔羊增重效果优于饲喂高NDF饲粮的羔羊。综合羔羊整个饲养阶段生长和消化代谢情况分析,饲养效果明显的4组顺序为EW-LL>EW-LH=EW-HH>ER-HH。本试验条件下推荐组合为早期断奶+育肥前期饲粮NDF水平33%+育肥后期饲粮NDF水平28%。

关键词: 湖羊, 早期断奶, NDF水平, 生长性能, 消化代谢, 叠加效果

Abstract:

【Objective】This study was conducted to explore the effects of early weaning and NDF levels of finishing diets on the growth performance, and nutrient digestion and metabolism of Hu sheep lambs, and to filter out the best combination of feeding methods by calculating the superposition effect between the experimental factors. 【Method】One hundred and twenty Hu lambs with similar body weight [(8.26±2.14) kg] and (20±2 ) days of age were randomly divided into four groups with six replicates in each group and five lambs in each replicate. NDF levels of early finishing diets were 33%(low) and 38%(high), NDF levels of late finishing diets were 28% (low) and 38% (high). Treatments included followings: early weaning (EW) + feeding low NDF diet in early and late finishing stage (EW-LL); early weaning + feeding low NDF diet in early finishing stage and high NDF diet in late finishing stage (EW-LH); early weaning + feeding high NDF diet in early and late finishing stage (EW-HH); ewe reared (ER) + feeding high NDF diet in early and late finishing stage (ER-HH). Early weaned lambs gradually transitioned from breastfeeding to feeding milk replacer at the age of 20 days and supplemented with starter feed. The fattening period was from 61 to 180 days of age. The trial lasted 160 days. The body weight and feed intake of lambs were measured at different stages, and digestibility tests were carried out at 2, 4 and 6 months of age.【Result】There was no significant difference in body weight and average daily gain among four groups (P>0.05) except the average daily gain of lambs from 46 to 65 days of age, which was higher in ER group compared with EW group (P<0.05). The dry matter intake of early-weaned lambs from 21 to 65 days old was significantly higher than that of ewe reared lambs (P<0.05), In the early weaned groups, the pellet intake of lambs fed low-NDF diets during the finishing stage were significantly higher than the other two groups at the age of 121-180 days (P<0.05). The nutrient digestibility, energy and nitrogen utilization of early weaned lambs were lower than those in the ER group at 55 to 65 days of age. But it was inverse at fattening period, the dry matter and organic matter digestibility of lambs fed low NDF diet was higher than those fed high NDF diet in finishing stage (P<0.05). EW-LL group had the highest ADG increase scope by superposition effect analysis. The superimposing effect of the two feeding methods of early weaning and low-NDF diet during the early finishing stage was -50.57%.【Conclusion】According to the whole fattening cycle, early weaning and feeding milk replacer could promote the growth performance of lambs. The fattening effect of the low NDF level diet in the early finishing stage was worse than the high NDF level diet. When lambs have the same diet in the late finishing stage, the weight gain of lambs fed with low NDF diet was better than that of lambs fed with high NDF diet in the early finishing stage. By the comprehensive analysis of the growth performance, digestion and metabolism of lambs, the priority of the combination of feed methods was EW-LL>EW-LH=EW-HH>ER-HH. The combination of early weaning + feeding low NDF diet in early and later finishing stage was recommended in this study.

Key words: Hu lamb, early weaning, NDF level, growth performance, digestion and metabolism, superimposition effect

黄文琴,吕小康,庄一民,崔凯,王世琴,刁其玉,张乃锋. 早期断奶和育肥期饲粮NDF水平对湖羊生长性能和消化代谢的影响[J]. 中国农业科学, 2021, 54(10): 2217-2228.

HUANG WenQin,LÜ XiaoKang,ZHUANG YiMin,CUI Kai,WANG ShiQing,DIAO QiYu,ZHANG NaiFeng. The Effects of Early Weaning and NDF Levels of Finishing Diets on Growth Performance, Nutrient Digestion and Metabolism of Hu Lambs[J]. Scientia Agricultura Sinica, 2021, 54(10): 2217-2228.

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项目 Items	开食料 Starter	育肥前期Early fattening		育肥后期Late fattening
项目 Items	开食料 Starter	低NDF Low NDF	高NDF High NDF	低NDF Low NDF	高NDF High NDF
原料Ingredients
葵花壳 Sunflower seed hull	-	10	16	10	10
大豆皮 Soybean hull	-	20	25	11	20
棕榈仁粕 Palm kernel meal	-	0	5	0	5
苜蓿Alfalfa hay	-	5	0	7.5	0
玉米Corn	50	35	25	45	35
豆粕Soybean meal	23.5	-	-	-	-
麸皮Wheat bran	10	0	5	5	5
膨化大豆 Extruded soybean	-	8	8	6	5
玉米干酒糟 DDGS	-	4.5	8	6	8
玉米胚芽粕 Corn germ meal	11.8	10	0	0	5
脂肪粉 Fat power	-	1.5	2	1.5	0.8
糖蜜 Molasses	-	2	2	2	2
小苏打NaHCO₃	0.5	-	-	-	-
食盐 Salt	0.5	0.5	0.5	0.5	0.5
石粉Limestone	2.0	0.5	0.5	0.5	0.7
磷酸氢钙 Dicalcium phosphate	0.5	1	1	1	1
膨润土 Bentonite	0.2	1	1	1	1
预混料Premix¹⁾	1.0	1	1	1	1
合计Total	100	100	100	100	100
营养水平 Nutrient levels
代谢能²⁾ME(MJ·kg^-1)	12.24	12.05	11.93	12.25	12.00
干物质 DM	90.66	91.70	91.68	89.48	90.18
粗蛋白质 CP	15.27	13.75	12.76	13.00	12.86
粗脂肪 EE	8.31	5.64	6.28	6.02	5.94
粗灰分 Ash	2.76	7.09	6.55	7.34	7.13
中性洗涤纤维 NDF	12.30	33.00	37.50	28.18	33.42
酸性洗涤纤维 ADF	4.01	18.13	21.37	13.99	19.98
钙 Ca	1.06	1.03	1.18	1.23	1.03
总磷 P	0.59	0.56	0.51	0.46	0.52

项目 Items	日龄 Days of age	组别 Groups				SEM	P
项目 Items	日龄 Days of age	EW-LL	EW-LH	EW-HH	ER-HH	SEM	P
体重 BW (kg)	25	8.13	8.12	8.12	8.71	0.20	0.678
	45	12.91	12.53	12.67	12.29	0.20	0.196
	65	18.49	17.71	18.22	19.25	0.71	0.531
	90	22.37	22.47	23.03	24.40	0.42	0.695
	120	28.93	28.68	29.46	27.31	0.79	0.339
	150	36.28	34.30	35.76	33.00	1.32	0.352
	180	41.85	39.52	41.24	37.06	1.60	0.199
平均日增重 ADG (g·d^-1)	25-45	234.62	206.14	211.63	202.41	10.10	0.154
	46-65	256.01b	265.28b	281.38b	311.42a	13.05	0.043
	25-65	252.68	233.02	227.41	258.16	7.49	0.086
	66-120	200.42	194.56	219.70	173.81	12.44	0.129
	121-180	227.29	236.37	200.25	166.92	19.47	0.093

项目 Items	日龄 Days of age	组别 Groups				SEM	P
项目 Items	日龄 Days of age	EW-LL	EW-LH	EW-HH	ER-HH	SEM	P
代乳粉采食量 Milk replacer intakes (g·d^-1)	21-45	109.74	108.17	108.88	-	-	-
开食料采食量 Starter intakes (g·d^-1)	21-45	283.90a	271.37a	298.76a	153.43b	14.37	0.000
	46-65	665.78	662.52	712.13	605.20	19.19	0.283
	21-65	474.84a	466.95a	505.45a	379.31b	15.60	0.017
干物质采食量DMI (g·d^-1)	66-120	823.43	801.96	918.77	824.83	20.27	0.174
	121-180	1417.02a	1119.32b	1168.14b	1124.56b	43.28	0.048
	66-180	1054.16	956.11	1039.89	970.41	29.66	0.590
NDF采食量 NDF intakes (g·d^-1)	66-120	271.74b	264.65b	333.75a	293.61ab	7.59	0.001
NDF采食量 NDF intakes (g·d^-1)	121-180	399.49	374.07	390.39	375.83	11.79	0.876
饲粮转化率 FCR	66-120	3.63	4.18	3.66	3.37	0.19	0.534
饲粮转化率 FCR	121-180	4.39	4.18	5.07	5.19	0.23	0.350

项目 Items	组别 Groups				SEM	P
项目 Items	EW-LL	EW-LH	EW-HH	ER-HH	SEM	P
55-65日龄 55-65 days of age
干物质 DM	77.23b	75.61b	80.28a	80.57a	0.62	0.004
有机物 OM	80.66b	79.32b	83.25a	83.50a	0.54	0.006
中性洗涤纤维 NDF	61.43	55.79	62.13	64.58	1.17	0.059
酸性洗涤纤维 ADF	49.55bc	42.02c	55.63ab	59.43a	2.17	0.001
总能 GE	74.24b	72.42b	78.09a	78.20a	0.71	0.001
氮 N	76.22a	70.45b	77.47a	79.86a	1.03	0.002
粗脂肪 EE	72.87ab	68.02b	76.03a	77.45a	1.26	0.045
115-125日龄 115-125 days of age
干物质 DM	70.73ab	71.80a	67.37bc	65.89c	0.82	0.017
有机物 OM	73.64a	74.22a	69.55b	69.09b	0.75	0.010
中性洗涤纤维 NDF	54.56	52.53	53.93	49.66	4.34	0.222
酸性洗涤纤维 ADF	49.94	47.67	46.43	44.82	1.08	0.478
总能 GE	69.81ab	70.75a	67.27b	67.48b	0.51	0.022
氮 N	72.73	74.21	71.14	70.37	0.63	0.135
粗脂肪 EE	89.71	91.07	88.59	89.25	0.60	0.553
170-180日龄 170-180 days of age
干物质 DM	76.19a	72.84b	73.79ab	71.45b	0.61	0.035
有机物 OM	79.73a	76.65b	77.70ab	75.89b	0.51	0.047
中性洗涤纤维 NDF	54.99	57.88	62.10	59.91	1.26	0.232
酸性洗涤纤维 ADF	52.87b	60.37a	60.93a	58.97a	1.09	0.035
总能 GE	71.23	71.57	73.12	71.79	0.69	0.807
氮 N	78.65a	73.53b	74.24b	73.29b	0.70	0.019
粗脂肪 EE	71.71	85.97	87.43	90.34	2.89	0.072

项目 Items	组别 Groups				SEM	P
项目 Items	EW-LL	EW-LH	EW-HH	ER-HH	SEM	P
50-60日龄 50-60 days of age
代谢能采食量ME intake (MJ·d^-1)	8.71ab	8.13b	9.40a	9.48a	0.19	0.041
总能代谢率Metabolic rate of GE (%)	61.13	62.99	62.49	62.87	1.35	0.968
总能沉积率Retained GE (%)	32.49	30.53	36.45	37.07	1.11	0.139
氮采食量N intake (g·d^-1)	24.54ab	22.89b	27.11a	26.69a	0.58	0.023
氮沉积率Retained N (%)	48.87ab	44.19b	54.79a	53.92a	1.36	0.010
115-125日龄 115-125 days of age
代谢能采食量ME intake (MJ·d^-1)	9.34	7.74	8.15	7.35	0.29	0.059
总能代谢率Metabolic rate of GE (%)	55.71	48.22	47.84	47.86	1.56	0.158
总能沉积率Retained GE (%)	45.57	40.10	35.22	34.92	2.19	0.237
氮采食量N intake (g·d^-1)	25.73	22.45	23.18	21.16	0.87	0.311
氮沉积率Retained N (%)	37.42	43.72	41.19	41.75	1.13	0.266
170-180日龄 170-180 days of age
代谢能采食量ME intake (MJ·d^-1)	9.85	8.78	9.58	9.18	0.27	0.567
总能代谢率Metabolic rate of GE (%)	32.45	38.62	45.25	43.31	1.10	0.230
总能沉积率Retained GE (%)	22.39	31.42	40.05	39.90	2.94	0.066
氮采食量N intake (g·d^-1)	24.35	23.28	25.40	24.33	0.70	0.793
氮沉积率Retained N (%)	35.48	31.53	29.47	33.55	2.00	0.757