Sebastiano Rocco S, Sweeney Torres, Keady Timothy W J, Hanrahan James P, Good Barbara
School of Veterinary Medicine University College, Belfield, Dublin 4, Ireland.
Animal & Grassland Research and Innovation Centre, Teagasc, Athenry, Co. Galway, Ireland.
Vet Parasitol. 2017 Feb 15;235:8-16. doi: 10.1016/j.vetpar.2016.12.019. Epub 2017 Jan 7.
Ewes experience a temporary decline in resistance to gastrointestinal nematodes (GIN) during the periparturient period, characterised by a rise in faecal egg count (FEC) that represents a major source of pasture contamination for naïve progeny. The aim of this study was to assess the effect of level of supplementation with digestible undegraded protein (DUP) during the last 6 weeks of pregnancy on periparturient FEC and the performance of ewes with a naturally acquired parasite infection. Eighty-five Belclare and Belclare x Scottish Blackface twin/triplet-bearing ewes were allocated to 1 of 4 dietary groups representing the combination of 2 concentrates (DUP concentration 29 and 94g/kg dry matter) with 2 levels of concentrate during the final 6 weeks of gestation (18 and 30kg in total for ewes with twins; 24 and 35kg for ewes with triplets). All ewes were housed during the pre-partum feeding period and offered grass silage ad libitum; food intake was recorded daily. The intake of DUP varied from 26 to 72g/d among treatments and was reflected in variation of 0.76 to 1.20 in metabolizable protein supply as a proportion of requirements. After lambing, ewes and lambs grazed on permanent sheep pasture, without concentrate supplementation, until weaning (14 weeks post lambing). The variables studied, from week 6 pre-lambing up to week 10 post-lambing, included: FEC, serum pepsinogen concentration, body weight (BW) and body condition score (BCS). The effect of week (relative to lambing date) on FEC was highly significant (P<0.001). However, diet did not influence FEC (P>0.05) at any stage either pre- or post-partum. Pepsinogen concentration also varied with time but was not influenced by dietary treatment (P>0.05). The changes in BW and BCS from 6 weeks before lambing to weaning were not affected by the concentration of DUP in the supplement but ewes on treatments involving the higher level of supplementation lost less BW and BCS (P<0.001). The results of this study indicate that the level of DUP supplementation during the last 6 weeks of pregnancy does not affect FEC, BW or BCS of housed ewes with a naturally acquired GIN infection.
母羊在围产期对胃肠道线虫（GIN）的抵抗力会暂时下降，其特征是粪便虫卵计数（FEC）升高，这是新生后代牧场污染的主要来源。本研究的目的是评估妊娠最后6周补充可消化非降解蛋白（DUP）的水平对围产期FEC以及自然感染寄生虫的母羊生产性能的影响。85只怀有双胞胎/三胞胎的贝尔克莱羊和贝尔克莱羊×苏格兰黑脸羊被分配到4个日粮组中的1组，这4个日粮组代表了2种精饲料（DUP浓度分别为29和94克/千克干物质）与妊娠最后6周2个精饲料水平（怀有双胞胎的母羊总量为18和30千克；怀有三胞胎的母羊总量为24和35千克）的组合。所有母羊在产前饲喂期圈养，并随意提供青贮草；每天记录采食量。各处理间DUP摄入量从26克/天到72克/天不等，可代谢蛋白供应量占需求量的比例在0.76至1.20之间变化。产羔后，母羊和羔羊在永久性绵羊牧场上放牧，不补充精饲料，直至断奶（产羔后14周）。研究的变量，从产前6周到产后10周，包括：FEC、血清胃蛋白酶原浓度、体重（BW）和体况评分（BCS）。周（相对于产羔日期）对FEC的影响非常显著（P<0.001）。然而，日粮在产前或产后的任何阶段都不影响FEC（P>0.05）。胃蛋白酶原浓度也随时间变化，但不受日粮处理的影响（P>0.05）。从产前6周到断奶，BW和BCS的变化不受补充料中DUP浓度的影响，但补充水平较高的处理组母羊BW和BCS的损失较少（P<0.001）。本研究结果表明，妊娠最后6周补充DUP的水平不会影响自然感染GIN的圈养母羊的FEC、BW或BCS。
