Effects of dietary chromium picolinate and ascorbic acid supplementation on egg production, egg quality and some serum metabolites of laying hens reared under a low ambient temperature (6 degrees C).

This experiment was conducted to evaluate the effects of chromium (chromium picolinate, Cr Pic) and vitamin C (L-ascorbic acid) supplementation on egg production and egg quality in laying hens (Hy-Line) kept at 18 degrees C (at thermo-neutral zone) or 6 degrees C (cold stress) in temperature-controlled rooms. One hundred and fifty laying hens (32 week-old) were divided into 5 groups, 30 hens per group. The laying hens kept at 6 degrees C temperature were fed either a basal diet (low temperature-basal diet, LTB group) or the basal diet supplemented with either 400 micrograms of Cr per kg diet (Cr group), 250 mg of L-ascorbic acid per kg diet (Vit C group) or 400 micrograms of Cr plus 250 mg of L-ascorbic acid per kg diet (Vit C + Cr group) while hens kept at 18 degrees C fed a basal diet (thermo-neutral-basal diet, TNB group). Performance and egg quality were significantly reduced in LTB group compared with TNB group. Supplemental chromium and vitamin C significantly increased live weight change, egg production, and improved feed efficiency in cold-stressed hens compared with group fed the basal diet at 6 degrees C brought up to the values of the group reared under thermoneutral conditions (18 degrees C). Egg production and egg weight were also greater in each supplemental group compared with the LTB group. Separately or as a combination, supplemental chromium and vitamin C increased serum insulin but decreased corticosterone, glucose and cholesterol concentrations. Results of the present study show that supplementing vitamin C and chromium, particularly as a combination, improved the performance of cold-stressed hens. Such a combination of supplement can offer a potential protective management practice in preventing cold stress-related losses in performance of laying hens.     

Chromium picolinate, rather than biotin, alleviates performance and metabolic parameters in heat-stressed quail

1. The effects of chromium picolinate and biotin supplementation alone and in combination on performance, carcase characteristics, malondialdehyde (MDA), vitamin C, vitamin E, glucose and cholesterol levels were evaluated in Japanese quail exposed to high ambient temperature. 2. Two hundred and forty quails (10d old) were assigned randomly to 4 dietary treatments at room temperature (22 degrees C; thermoneutral, TN) or ambient (34 degrees C for 8 h/d; heat stress, HS). Both TN and HS were fed either on a basal (control) diet or the basal diet supplemented with 400 microg of Cr/kg (Cr group), 0.5 mg of biotin/kg of diet (biotin group) or both (Cr + Biotin group). 3. Supplementing the diet of heat-stressed quails with chromium picolinate improved live weight gain, feed intake, feed efficiency and carcase traits. Biotin supplementation during TN and HS conditions did not have any beneficial effects on body weight gain, feed intake, feed efficiency or carcase traits. 4. Either in combination or alone, chromium picolinate increased serum concentrations of vitamins C and E, but decreased MDA, glucose and cholesterol concentrations in birds kept at high ambient temperature. There was no difference in vitamins C and E and MDA concentrations between birds given chromium picolinate and birds receiving chromium picolinate plus biotin, while glucose and cholesterol levels were significantly lower in all groups. The lowest concentrations of cholesterol and glucose were found in the combination group under both TN and HS conditions. An interaction between diet and temperature was detected for glucose and cholesterol concentrations. 5. Excretion rates for zinc, iron and chromium were lower in TN groups than in the corresponding HS groups. Supplementing diet with chromium picolinate and chromium picolinate plus biotin decreased excretion of minerals while biotin alone did not effect excretion of minerals. 6. Chromium supplementation, but not biotin supplementation, attenuated the decline in performance and antioxidant status resulting from heat stress.     

Vitamin E supplementation can alleviate negative effects of heat stress on egg production,egg quality,digestibility of nutrients and egg yolk mineral concentrations of Japanese quails

The aim of this study was to determine if the negative effects of high ambient temperature (34 degrees C) on egg production, egg quality, digestibility of nutrients, and mineral content of egg yolk could be alleviated by dietary vitamin E (dl-alpha-tocopheryl acetate) supplementation in laying Japanese quails (Coturnix coturnix japanica). Japanese quails (n=240; 7-week-old) were divided into eight groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with either 125, 250 or 500 mg of dl-alpha-tocopheryl acetate/kg of diet. Birds were kept at 22 degrees C and 55% relative humidity (RH). At 14 weeks of age, the thermo-neutral (TN) group remained in the same temperature as at the beginning of the experiment, whereas the heat stress (HS) group was kept at an environment-controlled room at 34 degrees C and 44% RH for 3 weeks. Heat exposure decreased performance when basal diet was fed (P=0.001). With 250 and 500 mg/kg of diet, an increase in body weight (P=0.01), feed intake (P=0.01), egg production (P=0.001), and improvement in feed efficiency (P=0.01) was found with vitamin E supplementation in quails reared under heat stress conditions (HS). Similarly, egg weight (P=0.01), egg specific gravity (P=0.01), egg shell thickness (P=0.05) and Haugh unit (P=0.01) were positively influenced by vitamin E supplementation. Heat exposure decreased digestibility of dry matter (DM) (P=0.03), organic matter (OM) (P=0.05), crude protein (CP) (P=0.02), ether extract (EE) (P=0.05) and were elevated by supplemental vitamin E (P相似文献   

饲粮中添加维生素E和有机硒对攸县麻鸭产蛋性能、蛋品质、血清生化指标及咸蛋蛋黄品质的影响

本试验旨在研究饲粮中添加维生素E和有机硒对攸县麻鸭产蛋性能、蛋品质、血清生化指标及咸蛋蛋黄品质的影响.选用200只健康的处于产蛋高峰期的攸县麻鸭,随机分为4个组,每组5个重复,每个重复10只鸭.对照组(Ⅰ组)饲喂基础饲粮,3个试验组(Ⅱ、Ⅲ、Ⅳ组)分别在基础饲粮中添加50 IU/kg维生素E、0.2 mg/kg硒、0....     

The effect of soy isoflavones on egg quality and bone mineralisation during the late laying period of quail

1. Soy isoflavones play a role in calcium and bone metabolism. Poor egg quality, skeletal abnormalities and architectural deterioration of bone tissue are common problems under hot climate conditions and with increased age in poultry. 2. In this study, we investigated the effects of soy isoflavone supplementation on egg production, egg quality, bone mineral density (BMD), levels of osteocalcin (OC), vitamin D, calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) activity in quail (Coturnix coturnix japonica) during the late laying period. 3. The birds (n = 180; 28 weeks old) were randomly assigned to 6 treatment groups consisting of 6 replicates of 5 birds each in a 2 x 3 factorial arrangement of treatments (temperatures, soy isoflavone concentration). Birds were kept in wire cages in a temperature-controlled room at either 22 degrees C (thermo-neutral, TN) or 34 degrees C (heat stress, HS) for 8 h/d (09:00 to 17:00 h; until the end of the study) and fed either on a basal (control) diet or on the basal diet supplemented with either 400 or 800 mg of soy isoflavones/kg of diet. 4. Heat exposure reduced feed intake, egg production, egg quality, BMD, OC, vitamin D, Ca, P and ALP when the basal diet was given. Feed intake, egg production and egg weight were not affected, while eggshell thickness and eggshell weight increased in soy isoflavone-supplemented quails reared under TN conditions. However, feed intake, egg production, egg weight, eggshell thickness, eggshell weight and Haugh units were positively influenced by soy isoflavone supplementation in HS groups for quail during the late laying period. Bone mineral density, serum OC, vitamin D, Ca, P levels and ALP activity were significantly improved by soy isoflavone supplementation in both the TN and HS groups in quail during the late laying period. 5. Soy isoflavone supplementation of basal diet significantly improved egg quality and bone mineralisation in quail during the late laying period.     

维生素E对免疫抑制产蛋鸡生产性能和蛋品质的调控效应

试验探讨维生素E对免疫抑制蛋鸡生产性能和蛋品质的调控效应,选取健康的尼克褐产蛋鸡270只,随机等分为5组,每组3个重复,每重复18只。第Ⅰ组为对照组,第Ⅱ~Ⅴ组为免疫抑制组,对第Ⅱ~Ⅴ组鸡在试验第5、6、7 d进行腿部肌肉注射80 mg/kgBW环磷酰胺(CTX),第Ⅰ组注射等量生理盐水。Ⅰ、Ⅱ组饲喂基础日粮(维生素E含量44.59 mg/kg),Ⅲ、Ⅳ、Ⅴ组在基础日粮中分别添加50、100、200 mg/kg维生素E。结果显示:①免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量显著降低(P<0.05),破蛋率显著升高(P<0.05)。基础日粮中添加50 mg/kg维生素E显著提高免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量(P<0.05),但仍低于对照组Ⅰ(P<0.05);显著降低料蛋比和破蛋率(P<0.05)。②免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位显著降低(P<0.05),蛋形指数和蛋黄颜色无显著改变(P>0.05);50 mg/kg维生素E添加量显著提高免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位(P<0.05),与对照组Ⅰ无显著差异(P>0.05)。因此,免疫抑制显著降低产蛋鸡的生产性能和蛋品质;基础日粮中添加维生素E对免疫抑制蛋鸡的生产性能和蛋品质具有明显的调控效应,且以50 mg/kg添加量效果较好。     

有机铬对热应激蛋鸡生产性能和血液生化指标的影响

试验选用91周龄新罗曼商品蛋鸡480只,按2×2双因子试验设计随机分为5组,对照组饲喂不添加铬的玉米-豆粕型基础日粮,4个试验组饲喂在基础日粮中分别添加了以吡啶羧酸铬或酵母铬来源的0.2mg/kg或0.4mg/kg的日粮,试验30d,以研究有机铬对热应激蛋鸡生产性能和血液生化指标的影响。试验结果显示:①有机铬能在一定程度上促进热应激蛋鸡的蛋白质利用,提高热应激蛋鸡的生产性能;②铬水平对血清尿素氮有极显著的影响(P<0.01),添加0.4mg/kg铬组均极显著地低于对照组(P<0.01),说明了补铬能够抑制由高温引起的蛋白质分解过程,从而起到缓解高温应激的作用;③吡啶羧酸铬和酵母铬在作用效果上无显著的差异;从经济效益方面考虑,0.4mg/kg铬水平的酵母铬和吡啶羧酸铬经济效益较高。     

饲粮中硒添加水平对产蛋高峰期临武鸭产蛋性能、蛋品质、血清抗氧化指标和蛋硒含量动态变化的影响

本试验旨在研究饲粮中硒添加水平对产蛋高峰期临武鸭产蛋性能、蛋品质、血清抗氧化指标和蛋硒含量动态变化的影响。试验选用29周龄体况良好、产蛋率接近的正处于产蛋高峰期的临武鸭200只,随机分为5组,每组5个重复,每个重复8只。对照组饲喂基础饲粮(不额外补充硒源,实测硒含量为0.15 mg/kg)45 d,Ⅰ组、Ⅱ组、Ⅲ组、Ⅳ组分别在基础饲粮中以酵母硒形式添加0.10、0.20、0.40、0.80 mg/kg的硒,饲喂35 d添加硒饲粮后改喂基础饲粮10 d。结果显示:1)饲粮中硒添加水平对蛋鸭产蛋性能和蛋品质各指标均无显著影响(P0.05)。2)与对照组和Ⅰ组相比,饲粮中添加0.40和0.80 mg/kg的硒可以显著提高蛋鸭血清中硒和谷胱甘肽(GSH)含量以及超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性(P0.05),显著降低血清中丙二醛(MDA)含量(P0.05)。3)随试验天数的增加,对照组和Ⅰ组蛋硒含量无显著变化(P0.05),而Ⅱ组、Ⅲ组、Ⅳ组蛋硒含量均呈现先升高后降低的趋势,且均在试验第9天达到峰值。试验第7、9、13、17、21、28和35天,Ⅱ组、Ⅲ组、Ⅳ组蛋硒含量显著高于对照组和Ⅰ组(P0.05);停喂添加硒饲粮的第1~4天,Ⅱ组、Ⅲ组、Ⅳ组蛋硒含量仍显著高于对照组(P0.05);停喂添加硒饲粮的第5~8天,Ⅲ组和Ⅳ组蛋硒含量显著高于对照组(P0.05);停喂添加硒饲粮的第9天,各试验组蛋硒含量均衰减至与对照组相同水平(P0.05)。由此可见,饲粮中添加不同水平的酵母硒形式的硒对产蛋高峰期临武鸭的产蛋性能和蛋品质均无不良影响。饲粮中添加0.40和0.80 mg/kg酵母硒形式的硒可以提高产蛋高峰期临武鸭的蛋硒含量、血清硒含量和抗氧化能力,延长蛋硒的存留时效。综合考虑各因素,产蛋高峰期临武鸭饲粮中硒(以酵母硒形式添加)的适宜添加水平为0.40 mg/kg。     

氧化鱼油对蛋鸡生产性能、蛋品质及血清抗氧化指标的影响

本试验旨在研究饲粮添加氧化鱼油对蛋鸡生产性能、蛋品质及血清抗氧化指标的影响。选择720只体重相近的38周龄海兰灰蛋鸡,随机分为4个组,每组6个重复,每个重复30只鸡。将新鲜鱼油和过氧化物值(POV)为1 200.10 meq O2/kg的氧化鱼油按不同比例分别加入基础饲粮中,组成新鲜鱼油组(FFO组)、0.25%氧化鱼油组(OFO1组)、0.50%氧化鱼油组(OFO2组)和1.00%氧化鱼油组(OFO3组)。试验期4周。结果表明,试验期内各氧化鱼油组显著降低了蛋鸡的平均蛋重(P<0.05),与FFO组相比,OFO1、OFO2和OFO3组平均蛋重分别降低了0.9%、0.9%和1.7%(P<0.05);氧化鱼油组显著降低了鸡蛋蛋黄颜色和哈氏单位(P<0.05),对蛋壳颜色影响差异不显著(P>0.05);与FFO组相比,OFO3组显著降低了蛋鸡血清谷胱甘肽过氧化物酶活性(P<0.05),显著提高了血清丙二醛含量(P<0.05)。由此可见,蛋鸡饲粮中鱼油被氧化在一定程度上影响了蛋鸡生产性能、蛋品质和血清抗氧化指标。     

硒和铬对蛋鸡脂质代谢及鸡蛋硒含量的影响

本试验旨在研究在蛋鸡日粮中添加酵母硒和吡啶羧酸铬及其互作对蛋鸡生产性能、脂质代谢及鸡蛋品质的影响.选用320只45周龄海赛克斯蛋鸡随机分为4组,每组4个重复,每个重复20只鸡,在基础口粮中分别添加0 mg/kg吡啶羧酸铬(Ⅰ组)、0.4 mg/kg吡啶羧酸铬(Ⅱ组)、0.5 mg/kg酵母硒(Ⅲ组)、0.4 mg/kg吡啶羧酸铬+0.5 mg/kg酵母硒(Ⅳ组),预饲1周,试验从46周龄持续到50周龄,试验期5周(35 d).结果表明,Ⅲ、Ⅳ组产蛋率极显著提高,料蛋比极显著降低(P<0.01).Ⅱ、Ⅳ组血清总胆固醇含量极显著降低(P<0.01),Ⅲ、Ⅳ组血清高密度胆固醇含量极显著升高(P<0.01).Ⅱ、Ⅲ、Ⅳ组蛋黄中的胆固醇含量与Ⅰ组差异极显著(P<0.01).Ⅲ、Ⅳ组与Ⅰ、Ⅱ组相比,鸡蛋硒含量极显著升高(P<0.01).Ⅲ、Ⅳ组在试验开始到第2周末鸡蛋硒含量极显著升高(P<0.01),从第2周末到第5周末,硒含量基本稳定,4个组均进入平台期.结果显示,吡啶羧酸铬极显著降低了血清及蛋黄中的胆固醇含量.酵母硒极显著提高了产蛋率,降低了料蛋比,并降低了蛋黄中胆固醇含量,提高了鸡蛋中的硒含量.同时添加吡啶羧酸铬和酵母硒极显著提高了产蛋率,降低了料蛋比,并降低了血清及蛋黄中的胆固醇含量,提高了血清中高密度胆同醇含量和鸡蛋中的硒含量.     

产蛋种鸡日粮中不同水平维生素E与有机和无机硒的效果研究

在３×５的两因子试验中,研究了不同添加水平维生素Ｅ（４、１４和２４ｍｇ／ｋｇ）与有机和无机硒（亚硒酸钠０．２０、０．３５和０．５０ｍｇ／ｋｇ,酵母硒０．３５和０．５０ｍｇ／ｋｇ）对褐壳蛋种母鸡在２０～４０周龄阶段生产繁殖性能和有关血液指标的影响。结果表明,产蛋母鸡的采食量、产蛋率、蛋重、产蛋量、饲料转化率和死淘率在３个维生素Ｅ添加水平间无差异;除了添加酵母硒０．５０ｍｇ／ｋｇ组蛋鸡的蛋重和产蛋量显著低于酵母硒０．３５ｍｇ／ｋｇ组以外,其它各项生产性能指标在各硒处理组间差异不明显。维生素Ｅ和硒可增加彼此在血液中的存留;当日粮中只补加维生素Ｅ４ｍｇ／ｋｇ时,将日粮亚硒酸钠硒添加水平由０．２０ｍｇ／ｋｇ提高到０．３５～０．５０ｍｇ／ｋｇ可使血浆α－生育酚含量由０．５０μｇ／ｍｌ上升到接近１．０μｇ／ｍｌ左右。     

日粮添加虾青素和维生素B2对鸡蛋品质的影响

试验旨在探究虾青素和维生素B2在日粮中的添加量对鸡蛋品质的影响。选择1200只体重相近、健康的45周龄海兰褐蛋鸡,随机分成5组,每组4个重复,每个重复60只鸡。对照组蛋鸡饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组蛋鸡饲喂固定比例的基础日粮和0.25%虾青素,混合不同含量的维生素B2(5.0、8.0、11.0、14.0 mg/kg)。预试期1周和正式试验期4周,预试期各组蛋鸡均饲喂基础日粮,正式试验期分别投放上面试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组的配比的饲料。结果表明,试验组蛋黄颜色、哈夫单位均显著高于对照组(P<0.05)。试验Ⅱ、Ⅲ、Ⅳ组鸡蛋粗脂肪含量显著低于对照组(P<0.05)。试验组鸡蛋平均蛋重、蛋壳厚度、蛋壳强度、蛋比重与对照组相比有增大的趋势。试验表明,日粮添加虾青素和维生素B2能提高蛋品质,添加0.25%虾青素和14.0 mg/kg维生素B2效果最好。     

包膜酸化剂和小肽螯合铁对夏季蛋鸡生产性能、蛋黄中微量元素 量及血清免疫和抗氧化指标的影响

本试验旨在研究包膜酸化剂和小肽螯合铁及其交互作用对夏季产蛋高峰期蛋鸡生产性能、蛋黄中微量元素含量以及血清免疫和抗氧化指标的影响.试验采用2×4双因子完全随机试验设计,其中饲粮中包膜酸化剂设2个添加水平,小肽螯合铁设4个添加水平.选用576只38周龄健康罗曼粉壳蛋鸡,随机分成8个组,每组6个重复,每个重复12只鸡.A、B、C和D组饲粮分别在基础饲粮中添加0 mg/kg包膜酸化剂以及0(对照组)、0.04％、0.08％和0.12％小肽螯合铁(铁含量分别为0、60、120和180 mg/kg);E、F、G和H组饲粮分别在基础饲粮中添加300 mg/kg包膜酸化剂以及0、0.04％、0.08％和0.12％的小肽螯合铁(铁含量分别为0、60、120和180 mg/kg).预试期l周,正试期6周.结果表明:1)包膜酸化剂和小肽螯合铁及其交互作用对第3周和第6周蛋鸡的平均日采食量、产蛋率和料蛋比均无显著影响(P＞0.05).G组第3周和第6周的平均日采食量均显著高于对照组和C、D组(P＜0.05);B组第6周的产蛋率显著高于对照组和D、E组(P＜0.05),且料蛋比显著低于D组(P＜0.05).包膜酸化剂对第3周末蛋鸡的蛋重、第6周末的蛋黄指数和哈氏单位有显著影响(P＜0.05);小肽螯合铁对第6周末的蛋黄指数有显著影响(P＜0.05),小肽螯合铁和包膜酸化剂的交互作用对第6周末的蛋黄指数有极显著影响(P＜0.01),对第6周末的哈氏单位有显著影响(P＜0.05).第3周末,G组的蛋重显著高于B组(P＜0.05),G和H组的蛋黄指数显著高于C组(P＜0.05);第6周末,C、D和G组的蛋重显著高于对照组(P＜0.05),F组的蛋黄指数显著高于C、D和E组(P＜0.05),E、F和G组的哈氏单位显著高于D组(P＜0.05).2)小肽螯合铁及包膜酸化剂和小肽螯合铁的交互作用对第3周和第6周末蛋鸡蛋黄中铁元素含量有极显著影响(P＜0.01).B、C、D、F、G和H组第3周和第6周末蛋黄中铁元素含量极显著高于对照组和E组(P＜0.01),且H组第3周末蛋黄中铁元素含量显著高于B和F组(P＜0.05);H组第3周末蛋黄中锌元素含量显著高于F组(P＜0.05),B组第6周末蛋黄中锌元素含量显著高于D组(P＜0.05).3)包膜酸化剂对蛋鸡血清中总超氧化物歧化酶(T-SOD)活性有极显著影响(P＜0.01),对血清丙二醛(MDA)含量有显著影响(P＜0.05);包膜酸化剂和小肽螯合铁的交互作用对血清T-SOD活性有极显著影响(P＜0.01).C组血清免疫球蛋白M(IgM)含量显著高于对照组(P＜0.05),D、E、F、G和H组血清T-SOD活性极显著高于对照组(P＜0.01);B、F和G组血清MDA含量显著低于对照组和E组(P＜0.05).综合考虑,饲粮中单独添加0.04％和0.08％的小肽螯合铁或与300 mg/kg包膜酸化剂复合添加均有利于维持和延长蛋鸡夏季的产蛋高峰期,改善蛋品质,增加蛋中铁元素的富集,增强机体抗氧化能力.     

吡啶甲酸铬对产蛋鸡的生物安全性评价

本试验旨在研究饲粮添加不同水平吡啶甲酸铬对北京红商品产蛋鸡产蛋性能、血液生理生化指标、器官发育和主要脏器组织病理学变化的影响,进而评价吡啶甲酸铬对产蛋鸡的生物安全性。试验采用单因子完全随机设计,选用360只23周龄北京红商品产蛋鸡,按产蛋率和体重一致的原则随机分为4个组,每个组6个重复,每个重复15只鸡。各组分别在玉米-豆粕型基础饲粮中添加0、0.6、4.0和6.0 mg/kg(以铬计)的吡啶甲酸铬。预试期21 d,正试期70 d。结果表明:1)饲粮铬添加水平对试验全期产蛋鸡产蛋性能和器官指数无显著影响(P0.05)。2)饲粮铬添加水平除显著提高试验第35天产蛋鸡血浆谷草转氨酶活性(P0.05)外,对其他血浆生化指标和血液常规生理指标均无显著影响(P0.05)。3)饲粮铬添加水平对产蛋鸡主要内脏器官的发育均无明显影响,同时均未观测到产蛋鸡的心脏、肝脏、肾脏、卵巢和输卵管组织出现明显的病理学变化。以上结果表明,产蛋鸡玉米-豆粕型饲粮中吡啶甲酸铬的推荐添加水平为0.6 mg/kg时,具有10倍的安全系数,即饲粮中以吡啶甲酸铬形式添加6.0 mg/kg铬对产蛋鸡是安全的。     

腐植酸对蛋鸡产蛋后期产蛋性能、抗氧化及促产蛋激素分泌的影响

试验旨在探究天然腐植酸和合成腐植酸对蛋鸡产蛋后期生产性能、蛋品质、血清生化指标、抗氧化指标和激素水平的影响。选取52周龄体重、产蛋率相近的海兰白蛋鸡405羽,随机分成3个组,每组9个重复,每个重复15羽。对照组饲喂基础饲粮(CON组),试验组在基础饲粮中分别添加1 000 mg/kg的天然腐植酸A(HAA组)和合成腐植酸B(HAB组),预试期2周,正试期8周。结果表明:与CON组相比,添加腐植酸均可提高平均蛋重(P<0.05),降低不合格蛋率(P<0.05)和料蛋比(P<0.01),其中HAA组产蛋率极显著提高,HAA组的料蛋比低于HAB组(P<0.01);饲粮添加腐植酸对蛋品质无显著影响;与CON组相比,HAA组血清中白蛋白含量降低(P<0.05),HAB组乳酸脱氢酶活性提高(P<0.05),HAA组与HAB组血清中甘油三酯含量均降低(P<0.01);相比于CON组,添加HAB可提高谷胱甘肽过氧化物酶活性(P<0.05);与CON组相比,饲粮中添加腐植酸提高了血清中促黄体素水平(P<0.01),对促卵泡素水平有升高趋势(P=0.060),且HAA组中促卵泡素水平高于HAB组(P<0.01)。结果提示,腐植酸可促进机体促性腺激素分泌,改善机体抗氧化水平,显著提高产蛋后期蛋鸡的生产性能,且天然提取的腐植酸作用效果更佳。     

半胱胺和酵母铬对生长肥育猪生产性能和胴体品质的影响

试验选择25 kg左右的"杜长大"三元杂交猪96头,采用2×2析因设计分成4组,每组6个重复,每个重复4头。对照组喂基础饲粮,酵母铬(Cr)组在基础饲粮中添加酵母铬(生长期和肥育期分别添加Gr 200、300μg/kg),半胱胺(CS)组在基础饲粮中添加半胱胺(生长期和肥育期分别添加CS 120、170 mg/kg),复合组在基础饲粮中同时添加酵母铬和半胱胺(生长期和肥育期分别添加Gr 200μg+CS 120 mg/kg、Gr300μg+CS 170 mg/kg)。试验分生长期和肥育期两阶段进行,研究半胱胺和酵母铬对生长肥育猪生长性能、胴体和肌肉品质的影响。结果表明,生长肥育猪饲粮中分别添加半胱胺和酵母铬,一定程度上可改善生产性能,提高日增重、降低饲料/增重比;二者同时添加时有提高日增重的趋势,但统计分析差异不显著(P>0.05)。饲粮中分别或同时添加半胱胺和酵母铬对胴体肌肉品质也有一定的改善作用,但统计分析差异不显著(P>0.05)。     

Vitamin C Overcomes the Detrimental Effect of Vanadium on Brown Eggshell Pigmentation

Phosphorus supplementation from poor quality feed-grade sources may introduce excessive levels of vanadium (V) into the diets of laying hens. Vanadium in the diet of chickens has been shown to be detrimental to egg production, albumen height, BW, and feed consumption. This study showed that dietary V also has a negative effect on the color of brown eggshells from commercial-type layers. Commercial-type brown egg layers were fed a cornsoybean meal basal diet supplemented with 0, 50, or 100 ppm of V as NH₄ VO₃ to determine the effect on shell pigmentation. Hens fed V at both dietary concentrations laid lighter colored eggs (less redness) after only 2 d. Another experimental group of the same type of hens that were fed lower V concentrations (0, 15, or 30 ppm) also had less shell pigmentation. After the detrimental “bleaching” effect on shell color was observed, these diets were supplemented with 1 of the following: no supplement, 100 ppm of vitamin C, 100 IU of vitamin E, or 100 ppm of β-carotene. Only vitamin C restored the eggshell color of eggs from hens fed both levels of V. When these same antioxidants were added as preventive agents to diets supplemented with 15 ppm of V before the effects of V were established, brown layers benefited again from 100 ppm of vitamin C but not from vitamin E or β-carotene.     

霉菌毒素吸附剂对产蛋鸡生产性能、蛋黄中微量元素含量、血清抗氧化和生化指标的影响

本试验旨在研究霉菌毒素吸附剂(分别命名为CZ和SF)对产蛋鸡生产性能、蛋黄中微量元素含量、血清抗氧化和生化指标的影响。选取216只38周龄健康的罗曼蛋鸡,随机分成3个组,每组6个重复,每个重复12只。对照组饲喂基础饲粮,试验组(CZ组、SF组)分别在基础饲粮中添加0.5 g/kg的CZ和SF。预试期为10 d,正试期为35 d。结果表明:1)与对照组相比,CZ组产蛋鸡试验3~5周产蛋率、日产蛋量显著提高(P0.05);饲粮中添加霉菌毒素吸附剂对产蛋鸡的平均蛋重、平均日采食量、料蛋比和死淘率均无显著影响(P0.05)。2)与对照组相比,各试验组产蛋鸡第14天和第35天蛋黄铜、锰含量均无显著差异(P0.05);CZ组第14天蛋黄锌含量显著提高(P0.05)。3)饲粮中添加霉菌毒素吸附剂对第14天和第35天产蛋鸡血清谷胱甘肽过氧化物酶活性和丙二醛含量无显著影响(P0.05)。与对照组相比,各试验组产蛋鸡第14天血清总抗氧化能力均显著提高(P0.05);SF组第35天血清总超氧化物歧化酶活性显著提高(P0.05)。4)与对照组相比,CZ组产蛋鸡血清碱性磷酸酶活性、葡萄糖含量显著降低(P0.05);SF组血清总胆固醇含量显著降低(P0.05)。由此可见,饲粮中添加霉菌毒素吸附剂CZ明显提高了产蛋鸡产蛋性能,2种吸附剂CZ和SF都增强了产蛋鸡血清抗氧化功能,改善了部分血清生化指标。     

Effect of different dietary levels of Yucca schidigera powder on the performance,blood parameters and egg yolk cholesterol of laying quails

A total of 135 laying quails (Coturnix coturnix japonica), 9 weeks old, were divided into three dietary treatment groups. Three replicates were assigned to each treatment group consisting of 15 birds per cage. The diet was supplemented with 0, 100 and 200 ppm Yucca schidigera powder and given ad libitum to the quails for a period of 14 weeks. Body weight, egg production, feed consumption and feed efficiency were not different due to dietary treatments among the groups. Increased egg weight was determined in the control group. Yucca powder supplementation decreased serum glucose, cholesterol triglyceride level in laying quails. Serum total protein concentration was not changed by dietary treatments but albumin level was decreased in quails fed 100 ppm yucca powder. Egg yolk cholesterol concentration was not significantly different among the groups but tended to decline (11.5%) as a result of yucca supplementation. Red Blood Cell (RBC) and White Blood Cell (WBC) counts, packed cell volume (PCV), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) were not affected by supplementation of yucca powder. However, haemoglobin (HB) concentration was slightly increased and mean corpuscular haemoglobin concentration (MCHC) was significantly increased by 200 ppm yucca powder supplementation to the diet.     

Ascorbic acid and melatonin reduce heat-induced performance inhibition and oxidative stress in Japanese quails

1. The effects of ascorbic acid (L-ascorbic acid) and melatonin supplementation on performance, carcase characteristics, malondialdehyde (MDA) as lipid peroxidation indicator, ascorbic acid, retinol, tocopherol and mineral status in the Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature were evaluated. 2. Two hundred and forty Japanese quails (10 d old) were randomly assigned to 8 treatment groups consisting of 10 replicates of three birds each. The birds were kept in a temperature-controlled room at 22 degrees C (Thermoneutral, TN groups) or 34 degrees C (for 8 h/d; 09:00 to 17:00 h; Heat stress, HS groups). Birds in both TN and HS were fed either a basal (control) diet or the basal diet supplemented with 250 mg of L-ascorbic acid/kg of diet (Ascorbic acid group), 40 mg of melatonin/kg of diet (Melatonin group) or both (Ascorbic acid + Melatonin group). 3. Supplementing heat-stressed quails with ascorbic acid and melatonin improved performance compared with the control group. Effects generally were greatest in quails supplemented with both ascorbic acid and melatonin. 4. Although supplementation did not consistently restore the concentrations of serum ascorbic acid, retinol and tocopherol to those of TN groups, these concentrations increased significantly with supplementation. Furthermore, serum and liver MDA and serum cholesterol and glucose concentrations were lower in the supplemented groups than in the heat-stressed controls. 5. Within each environment, excretion of Ca, P, Mg, Zn, Fe and Cr were lowest in the combination group and, in all cases, highest in the HS group. Interactions between diet and temperature were detected for live weight gain, cold carcase weight, MDA, ascorbic acid, tocopherol concentrations and excretion of zinc. 6. The results of the study indicate that ascorbic acid and melatonin supplementation attenuate the decline in performance and antioxidant and mineral status caused by heat stress and such supplementation may offer protection against heat-stress-related depression in performance of Japanese quails.