凹凸棒石黏土对饲料颗粒质量及樱桃谷肉鸭生长性能、屠宰性能、肌肉品质和抗氧化性能的影响

Effect of different levels of palygorskite supplementation on pellet quality,growth performance,slaughter performance,meat quality and antioxidant ability in Cherry Valley ducks

[目的]本试验旨在研究日粮中添加不同水平的凹凸棒石黏土(凹土)对饲料颗粒质量及樱桃谷肉鸭生长性能、屠宰性能、肌肉品质和抗氧化性能的影响。[方法]按照随机区组试验设计,将720只1日龄的樱桃谷肉鸭随机分为4个处理组,每组6个重复,每个重复30只。分别饲喂基础日粮(对照组)及添加5、10和20 g·kg^(-1)凹土的试验日粮。试验期42 d,1~14 d为前期,15~42 d为后期。试验结束时,每重复随机抽取1只公鸭屠宰,用于各项指标测定。[结果]与对照组相比,添加3种不同水平凹土均显著提高肉鸭前期饲料颗粒硬度以及降低前期饲料的含粉率(P<0.05),添加20 g·kg^(-1)凹土使后期饲料的颗粒硬度显著提高(P<0.05),但其他凹土添加水平对后期饲料的颗粒硬度及含粉率无显著影响(P>0.05)。与对照组相比,添加3种不同水平的凹土对樱桃谷肉鸭的终末体质量、平均日采食量、平均日增重和料重比均无显著影响。与对照组相比,日粮中添加10 g·kg^(-1)凹土显著提高胸肌率、腿肌率与瘦肉率,添加20 g·kg^(-1)凹土显著提高腿肌率与瘦肉率,但对胸肌率没有影响(P>0.05),其中,就腿肌率而言,10 g·kg^(-1)凹土添加水平较20 g·kg^(-1)凹土添加水平提高显著。与对照组相比,添加3种水平凹土均显著降低胸肌的滴水损失,添加20 g·kg^(-1)凹土显著降低胸肌的蒸煮损失,添加10 g·kg^(-1)凹土显著降低胸肌的红度值(a*)和腿肌的滴水损失。与对照组相比,日粮中添加10和20 g·kg^(-1)凹土均显著提高胸肌的超氧化物歧化酶(SOD)活性,添加5 g·kg^(-1)凹土显著提高胸肌的谷胱甘肽过氧化物酶(GSH-Px)活性;添加10 g·kg^(-1)凹土显著提高腿肌SOD活性,添加3种水平凹土均显著降低腿肌中丙二醛(MDA)含量。[结论]在本试验条件下,基础日粮中添加凹土能改善饲料颗粒质量,提高樱桃谷肉鸭的屠宰性能,改善肌肉品质,提高肌肉的抗氧化能力,对肉鸭的生长性能无显著不利影响,其最佳添加水平为10 g·kg^(-1)。

[Objectives]This study was conducted to investigate the effect of different levels of dietary palygorskite supplementation on pellet quality,growth performance,slaughter performance,meat quality and antioxidant ability in Cherry Valley ducks.[Methods]According to the randomized block design,a total of 720 one-day-old Cherry Valley ducks were randomly divided into 4 dietary treatment groups with 6 replicates of 30 ducks per replicate,and fed a basal diet supplemented with 0(control group),5,10 and 20 g·kg-1 palygorskite.The experiment period was 42 days,which consisted of the starter period(1 to 14 days)and grower period(15 to 42 days).At the end of the experiment,1 male duck per replicate was randomly selected for measuring the relevant indexes.[Results]Compared with the control group,three levels palygorskite supplementation increased the hardness and decreased the fines percentage of pellet during starter period(P<0.05).The inclusion of 20 g·kg-1 palygorskite increased the pellet hardness of pellet during grower period(P<0.05),and other levels palygorskite supplementation did not affect the pellet hardness and the fines percentage of pellet during grower period(P>0.05).Palygorskite supplementation,regardless of levels,did not affect the final body weight,average daily feed intake,average daily weight gain and the ratio of feed intake to gain(F/G)of ducks.However,the percentage of breast muscle,leg muscle and lean muscle increased when supplementing 10 g·kg-1 palygorskite(P<0.05),and the inclusion of 20 g·kg-1 palygorskite increased the percentage of leg muscle and lean muscle(P<0.05),but had no effect on the percentage of breast muscle(P>0.05).10 g·kg-1 palygorskite supplementation showed higher leg muscle percentage than 20 g·kg-1 palygorskite supplementation(P<0.05).In addition,three levels palygorskite supplementation all significantly decreased the drip loss of breast muscle(P<0.05).The inclusion of 20 g·kg-1 palygorskite decreased the cooking loss of breast muscle(P<0.05).Similarly,the redness(a*)of breast muscle and the drip loss of leg muscle decreased significantly(P<0.05)when the palygorskite inclusion dosage was 10 g·kg-1.10 and 20 g·kg-1 palygorskite supplementation all significantly increased the superoxide dismutase(SOD)activity of breast muscle(P<0.05),and 5 g·kg-1 palygorskite supplementation increased the glutathione peroxidase(GSH-Px)activity of breast muscle(P<0.05).The inclusion of 10 g·kg-1 palygorskite supplementation increased the superoxide dismutase activity of leg muscle.Whereas the malonaldehyde(MDA)contents of leg muscle decreased significantly(P<0.05)by three levels palygorskite supplementation.[Conclusions]The basic dietary palygorskite supplementation could improve the feed pellet quality,enhance slaughter performance and meat quality,and increase antioxidant ability,and had no disadvantageous effect on the growth performance of Cherry Valley ducks.In addition,the optimal level of supplemented palygorsskite in the pellet diets of ducks was 10 g·kg-1.