Effects of zinc and vitamin A supplements on plasma levels of thyroid hormones, cholesterol, glucose and egg yolk cholesterol of laying hens

The effects of zinc and vitamin A supplementation to the diet on some blood metabolites were evaluated in Hisex brown laying hens from 56 weeks to 68 weeks of age. A total of 130 birds were divided into two main groups according to vitamin A treatment (0 and 3.44 mg retinyl acetate kg(-1) feed, respectively), each consisting of 65 hens. Hens in both of the main groups were then divided into five zinc treatment groups (0, 25, 50, 100 and 200 mg zinc kg diet(-1) respectively) of 13 hens each. It was observed that plasma T4, T3 and total cholesterol levels were affected by only zinc supplementation. While 100 and 200 mg Zn kg(-1) decreased plasma T4 level compared to control value, plasma T3 level was reduced by 100 mg Zn kg(-1) compared to groups fed less Zn. Adding 50 and 200 mg Zn kg(-1) to the diet increased plasma total cholesterol level in the birds compared to other groups. Vitamin A, zinc, and their interaction did not influence the concentration of plasma high-density lipoprotein (HDL)-cholesterol, glucose and egg yolk cholesterol in laying hens.     

Effects of inulin on performance, egg quality, gut microflora and serum and yolk cholesterol in laying hens

1. The present study was conducted to investigate the effects of inulin on laying hens. A total of 360 Brown Nick laying hens were divided randomly into 6 groups of 60 with 6 replicates of 10 hens and fed on diets containing 0 (control), 0·1, 0·5, 1·0, 1·5 or 2·0% inulin during the 4-week trial. 2. Dietary supplementation of inulin reduced cholesterol concentration (mg/g yolk) and content (mg/egg) in eggs. Cholesterol content in eggs decreased linearly with increasing levels of dietary inulin level. 3. Supplementation of inulin in diets decreased coliform bacteria counts and pH in the caecum. The lowest coliform bacteria counts (6·30 ± 0·03 log10 cfu/g) and pH (6·47 ± 0·01) were obtained in the 2·0% inulin group, the two indices decreasing by 21·6% and 3·0% respectively, compared with the control group. Coliform bacteria count and pH were changed linearly in accordance with increasing levels of dietary inulin level. Caecal Bifidobacteria counts were increased in the 2·0%-inulin group. 4. Inulin supplementation of layer diets did not appear to have any adverse effects on laying rate, egg weight, feed intake, feed conversion efficiency, cracked-egg rate, eggshell thickness or Haugh unit compared with the control laying hens. 5. Therefore, dietary supplementation with inulin may lead to the development of low-cholesterol chicken eggs as demanded by health-conscious consumers.     

The impact of phytoestrogen source supplementation on reproductive performance,plasma profile,yolk fatty acids and antioxidative status in aged laying hens

The objectives of this study were to investigate the effects of flaxseeds and/or fenugreek seeds as a source of phytoestrogens in laying feed on productive performance, egg quality, yolk fatty acids, plasma profile and antioxidative status in aged laying hens. A total of 120 Bovans Brown hens at 65 weeks of age were housed individually in laying cages in an open‐sided building under a 16‐hr light: 8‐hr dark lighting schedule. Hens were randomly divided into four experimental treatments (n = 30 each): (a) control (basal diet without any supplementation); (b) 1 g/kg of flaxseeds; (c) 1 g/kg of fenugreek seeds; and (d) combination of 1 g/kg flaxseeds and 1 g/kg fenugreek seeds from 65 to 71 weeks of age. Hen‐day egg production and egg mass were significantly increased by dietary supplementation of flaxseeds and/or fenugreek seeds, while feed intake was not affected; thus, feed conversion ratio was improved (p < 0.05). Weights of egg, albumen, yolk and shell were increased by the dietary treatments. Shell thickness and yolk colour were improved by supplementation of flaxseeds and/or fenugreek seeds. Yolk crude protein was not significantly affected by treatments; however, crude fat and calcium contents in yolk were increased and egg yolk cholesterol content was decreased. Interestingly, dietary supplementation of flaxseeds, fenugreek seeds and their combination had a significant positive effect on plasma luteinizing hormone, follicle‐stimulating hormone, oestradiol‐17β and triglycerides. Inclusion of flaxseeds and/or fenugreek seeds in the diets enhanced the serum glutathione peroxidase and superoxide dismutase activities and reduced the malondialdehyde and total cholesterol concentrations in plasma. Dietary supplementation of flaxseeds and/or fenugreek seeds increased α‐linolenic and linoleic acids in egg yolk. It could be concluded that inclusion of mixed sources of phytoestrogens in diets improved laying performance, egg quality, the antioxidative status, hormonal profile and steroidogenesis in aged laying hens.     

Egg production of light and medium hybrids given diets varying in energy level during the chick,rearing and laying stages

A total of 1000 birds, one‐half of which were light and the other half medium hybrids, were given diets containing either high or low levels of metabolisable energy ad libitum during the chick (0.6 weeks), rearing (6–16 weeks), early laying (first 8 months) and late laying (last 4 months) stages.

The medium hybrids ate more and were heavier than the lighter hybrids at all stages. More eggs were laid by the light than by the medium hybrids but the latter laid larger eggs so that the total weight of eggs laid did not differ significantly between the two groups.

Medium hybrids given a low‐energy chick diet laid more eggs subsequently than those given a high‐energy chick diet, while the opposite result was obtained for the light hybrids.

Birds given a low‐energy rearing diet were lighter at 16 weeks and subsequently laid more eggs than birds reared on a high‐energy diet.

During the first part of the laying period consumption of the low‐energy diet was greater than that of the high‐energy diet, but the level and efficiency of egg production were the same for both dietary treatments. Mortality during lay was not significantly affected by dietary treatment or breed.     

鲜茶叶粉对蛋鸡生产性能、蛋品质、蛋黄脂肪酸水平及经济指标的影响

文章旨在评估日粮添加不同水平的鲜茶叶粉对蛋鸡生产性能、蛋品质及蛋黄脂肪酸水平的影响.试验将672只产蛋性能一致的28周龄海兰褐壳蛋鸡随机分为4组,每组4个重复,每个重复42只.对照组饲喂基础日粮,处理组蛋鸡分别饲喂基础日粮+20(T1)、40(T2)和60?mg/kg(T3)鲜茶叶粉,试验为期6周.结果:与对照组相比,...     

益生茵对断奶仔猪生长表现、微生物区系和小肠黏膜结构的影响

为研究不同益生菌对断奶仔猪生长表现、微生物区系和小肠黏膜绒毛结构的影响,试验选用7kg杜×(长·大)三元杂种断奶仔猪112头,按体重、性别、窝别分至如下7个处理组(1)对照组(不添加益生菌);(2)200×10-6肠球菌制剂组;(3)1 000×10-6肠球菌制剂组;(4)200×10-6乳杆菌制剂组;(5)1 000×10-6乳杆菌制剂组;(6)200×10-6肠球菌与乳杆菌的混合菌制剂组;(7)1 000×10-6肠球菌与乳杆菌的混合菌制剂组.每处理2个重复(栏),每重复8头猪.测定断奶后两周和试验全期仔猪的生长表现,以及断奶两周末仔猪胃内容物pH、回肠内容物微生物区系、小肠黏膜绒毛高度与隐窝深度.结果表明,1)在断奶后两周内,益生菌极显著增加仔猪日采食量与料重比,各试验组均值分别较对照组高14%和10%(P＜0.01),益生菌有提高仔猪日增重的趋势(P=0.090 1),其中,1 000×1-6乳杆菌制剂组仔猪日增重较对照组增加20.6%(P＜0.05);在试验全期(7～19kg),益生菌降低仔猪采食量(P＜0.05),而对日增重与料重比没有影响(P＞0.05).2)益生菌对断奶后两周末仔猪胃内容物pH(P=0.841 8)、回肠大肠杆菌(P=0.503 9)及乳酸杆菌数量(P=0.139 7)均无显著影响.3)益生菌对仔猪绒毛高度/隐窝深度比值影响显著,各试验组均值较对照组增加17.7%(P=0.023 8),并有增加小肠黏膜绒毛高度的趋势,试验组小肠黏膜绒毛高度均值较对照组高12.8%P=0.053 8),但对仔猪小肠黏膜隐窝深度没有影响(P＞0.05).以上结果提示,益生菌能提高断奶仔猪的生长表现,改善小肠黏膜结构,不失为抗断奶应激添加剂的一种理想选择.     

Influence of sumac (Rhus Coriaria L.) and ginger (Zingiber officinale) on egg yolk fatty acid,cholesterol and blood parameters in laying hens

The aim of the study was to evaluate the potential effect of different levels of sumac (Rhus coriaria L.) seed powder and ginger (Zingiber officinale) root powder on egg yolk fatty acid composition, blood/yolk cholesterol in laying hen. A total of 63 (ATAK‐S: Domestic Turkish Laying Hens) laying hens (average weight: 1470 g each hen, 25‐weeks of age) were assigned to seven treatment diets including sumac seed (S) and ginger root powder (G) at 0 g/kg (control), 10 g/kg (S1), 20 g/kg (S2), and 30 g/kg (S3); 10 g/kg (G1), 20 g/kg (G2), or 30 g/kg in rations respectively, for 8 weeks. After a two‐week adaptation period to cages, the hens were allocated to 7 groups with 9 replicates of 1 hen in per cage each. The replications were allotted equally into the upper and lower cages to minimize the effects of cage level. In this study, egg yolk cholesterol had a decrease (p <0.05) in supplemented diet( sumac seed and ginger root powder). Fatty acid content in yolk; saturated fatty acid, monounsaturated fatty acids, polyunsaturated fatty acids and rate of n6/n3 were not significant (p <0.05). However, dietary supplementation with sumac and ginger powder reduced and yolk/blood cholesterol concentrations in laying hens. Supplementation of sumac and ginger affected on HDL, there was found a significant effect (p < 0.05) in treatment groups. Moreover, LDL positively decreased in all treatment groups compared with the control group. The findings of this study suggested that feeding sumac and ginger tend to be decreasing cholesterol levels in both yolk and blood on laying hens. It can be concluded that ginger root and sumac seed powder can be used as an effective feed additive to improve fatty acid composition and yolk and blood cholesterol in ATAK‐S laying hens.     

Plasma alkaline phosphatase and production traits in laying hens as influenced by dietary protein,strain and age

1. Plasma alkaline phosphatase (ALP) activity was determined in 4 laying strains (White Leghorn, New Hampshire, Native Brown and Native Barred) at 48 and 54 weeks of age. Birds were fed 1 of 2 isoenergetic diets with calculated crude protein contents of 152 and 181 g/kg. 2. No significant differences in plasma ALP activity were noted between the strains, although significant differences in laying performance between strains were evident. 3. There was no response in plasma ALP activity to the high dietary protein level in any strain. Depressed plasma ALP activity was associated with increasing age of birds. 4. The results failed to confirm the suggestion that ALP activity is related to egg production of the laying hen.     

Effect of hens fed dietary flaxseed with and without a fatty liver supplement on hepatic,plasma and production characteristics relevant to fatty liver haemorrhagic syndrome in laying hens

1. Two long-term experiments were conducted with Single Comb White Leghorn (SCWL) hens (line UCD-003) predisposed to fatty liver haemorrhagic syndrome (FLHS). The first investigated the effect of adding a fatty liver supplement to the diet of laying hens prior to the onset of lay, and continuing either until peak production or throughout 39 weeks into lay. The second experiment, lasting 9 months into lay, investigated the effect of adding a fatty liver supplement, with or without 100 g/kg dietary ground flaxseed, to the diet. Body weight, feed intake, plasma triglycerides (in experiment 2) and egg production were measured throughout the experiment. Liver weight, liver fat content, liver malondialdehyde (MDA) content and liver haemorrhage score and fatty acid content of liver fat (in experiment 2) were measured at the end of each experiment. 2. In experiment 1, hens given diets containing the fatty liver supplement had higher egg production and eggshell strength, but there was no difference in liver parameters including MDA content or haemorrhage score compared with controls. 3. At the end of experiment 2, hens on 100 g/kg flaxseed diets had lower body weight, liver weight, liver dry matter and fat content, and plasma triglyceride concentrations than hens given the control diets. 4. Liver haemorrhage score was positively correlated with liver weight, but not with liver fat content, plasma triglyceride concentration or liver MDA content. This suggests that reducing the liver lipid content or feeding fatty liver supplements may not be as effective in controlling FLHS as controlling the size of the liver.     

Deposition of orally administered β‐carotene, β‐apo‐8'‐carotenoic acid ethyl ester and zeaxanthin in the egg yolk by laying hens

An analytical procedure was adapted to determine separately the carotene and xanthophyll pigments of egg yolk. The transfer of β‐carotene, the ethyl ester of β‐apo‐8'‐carotenoic acid and zeaxanthin from the diet to the yolk was measured in hens which had been previously depleted of pigments by feeding a diet of low pigment content. The pigments were either dispersed in gelatin or dissolved in oil and were administered once daily in gelatin capsules. The pigments dispersed in gelatin were transferred to the yolks to a greater extent than those dissolved in oil. During the period when the yolk colour intensity was at a maximum the following recoveries of the dietary pigments were found for the pigments dispersed in gelatin: β‐carotene, o%, ethyl ester of β‐apo‐8'‐carotenoic acid, 8%, and zeaxanthin, at least 75%. The colour of mixed yolk was assessed visually using a 12‐degree colour scale. This procedure showed that a particular intensity of colour judged by visual assessment, encompassed a wide range of pigment concentrations and there was considerable overlap between concentrations equivalent to different degrees of colour. The light absorbance of a solution of xanthopylls is less than that of a solution of carotenes of equal concentration and thus for a given intensity of colour a yolk would contain much more zeaxanthin than the ethyl ester of β‐apo‐8'carotenoic acid.     

一株牦牛源屎肠球菌对小鼠肠道微生物、形态和免疫功能的影响

为研究牦牛肠黏膜源屎肠球菌G2对健康小鼠肠道微生物、形态和免疫功能的影响,试验设置对照组(CON)、热灭活菌组(EHK)、活菌组(ENT)3个处理组,每组8只C57BL/6小鼠,共计24只。CON组、EHK组、ENT组于正式试验期第1、2、4、6天按0.1 mL/只分别灌胃M17培养基、热灭活菌液和活菌菌液,灌胃前无菌收集小鼠粪便进行乳酸菌总菌计数,第8天处死小鼠取样。结果表明:ENT组乳酸菌总菌数量在第3、5天显著大于CON组与EHK组(P <0.05);各组小鼠结肠病理学评分无显著差异,但ENT组隐窝深度显著高于CON组与EHK组(P <0.05);各组间肠黏膜免疫因子Reg3β、Reg3γ和MUC2基因mRNA表达量差异不显著,TNF-α表达量ENT组显著低于CON组(P <0.05)。综上可知,牦牛源屎肠球菌G2可能为一种肠道过路菌,能在短时间内提高肠道乳酸菌的总数,一定程度上具有改善肠道形态和促进肠道健康的作用。     

Long‐term feeding effects of dietary protein levels on egg production,immunocompetence and plasma amino acids of laying hens in subtropical condition

The objective of this study was to determine the effect of protein levels on production performance, immune response, liver triglyceride and plasma amino acids profile of laying hens during 21–48 weeks of age. Two groups of commercial hens (Babcock B‐308) were fed with diets with different crude protein levels (14% and 18% CP). The high protein diet (18% CP) significantly increased production performance, essential amino acid intake, spleen weight (% of body weight), ND‐titre (haemagglutination‐inhibition test), serum albumin (g/dl), serum alpha‐globulin and plasma essential amino acids (except histidine) and decreased liver triglyceride (mg/g liver) in relation to the low protein diet (14% CP). In long‐term effect, therefore, this study suggested that adequate dietary condition of amino acids, particularly methionine and branch‐chain amino acids is necessary for sustaining normal immunocompetence and achieving maximum production performance.     

Feeding of different levels of metabolite combinations produced by Lactobacillus plantarum on growth performance,fecal microflora,volatile fatty acids and villi height in broilers

The effects of feeding different dosages of metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456) on the performance of broiler chickens was studied. A total of 504 male Ross broilers were grouped into 7 treatments and offered different diets: (i) standard corn‐soybean based diet (negative control); (ii) standard corn‐soybean based diet +100 ppm neomycin and oxytetracycline (positive control); (iii) standard corn‐soybean based diet + 0.1% metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456); (iv) standard corn‐soybean based diet + 0.2% of Com3456; (v) standard corn‐soybean based diet + 0.3% of Com3456 (vi) standard corn‐soybean based diet + 0.4% of Com3456 and (vii) standard corn‐soybean based diet + 0.5% of Com3456. Supplementation of Com3456 with different dosages improved growth performance, reduced Enterobacteriaceae and increased lactic acid bacteria count, and increased villi height of small intestine and fecal volatile fatty acid concentration. Treatment with 0.4% and 0.2% Com3456 had the best results, especially in terms of growth performance, feed conversion ratio and villi height among other dosages. However, the dosage of 0.2% was recommended due to its lower concentration yielding a similar effect as 0.4% supplementation. These results indicate that 0.2% is an optimum level to be included in the diets of broiler in order to replace antibiotic growth promoters.     

Effects of liquid metabolite combinations produced by <Emphasis Type="Italic">Lactobacillus plantarum</Emphasis> on growth performance,faeces characteristics,intestinal morphology and diarrhoea incidence in postweaning piglets

A study was carried out to investigate the effects of feeding liquid metabolite combinations produced by Lactobacillus plantarum strains on growth performance, diarrhoea incidence, faecal pH, microfloral counts, short-chain fatty acids (SCFA) and intestinal villus height and crypt depth of postweaning piglets. A total of 120 piglets (26 days old) were randomly assigned evenly into five treatment groups treated with same basal diet: (1) −ve control (free antibiotic); (2) + ve control (0.03% of chlortetracycline); (3) Com 1 (0.3% metabolite of TL1, RG11 and RI11 strains); (4) Com 2 (0.3% metabolite of TL1, RG14 and RS5 strains); (5) Com 3 (0.3% metabolite of RG11, RG14 and RI11 strains). After 5 weeks, the average daily feed intake was not significantly different (P > 0.05) among the treatments and feed conversion ratio was the highest (P < 0.05) in the −ve control group. In addition, diarrhoea incidence was reduced when piglets were fed with metabolite combinations. Faecal lactic acid bacteria (LAB) counts were significantly higher (P < 0.05) in metabolite treatment groups than in the groups without metabolites. However, the treatment of Com 2 metabolite resulted lower (P < 0.05) faecal pH and Enterobacteriaceae (ENT) than the −ve control group. In contrast, total faecal SCFA of Com 2 were significantly higher (P < 0.05) than the −ve control group. The villus height of duodenum was higher (P < 0.05) in the + ve control and Com 2 groups as compared to −ve control group. The results obtained in this study showed that feeding metabolite combinations could improve growth performance, and increase the population of gut LAB and faecal SCFA of postweaning piglets.     

Hydrolysis of phytic acid by intrinsic plant and supplemented microbial phytase (Aspergillus niger) in the stomach and small intestine of minipigs fitted with re-entrant cannulas. 3. Hydrolysis of phytic acid (IP6) and occurrence of hydrolysis products (IP5, IP4, IP3 and IP2)

Hydrolysis of phytate in the stomach and the small intestine as influenced by intrinsic plant (wheat) and supplemented microbial phytase (Aspergillus niger) were investigated with six minipigs (40-50 kg initial body weight) fitted with re-entrant cannulas in the duodenum, 30 cm posterior to the pylorus (animals 1, 4, 5 and 6) and ileocecal re-entrant cannulas, 5 cm prior the ileocecal junction (animals 1, 2 and 3), respectively. Dietary treatments were as follows: (1) diet 1, a corn-based diet [43 U phytase/kg dry matter (DM)]; (2) diet 2, diet 1 supplemented with microbial phytase (818 U/kg DM); and (3) diet 3, a wheat-based diet (1192 U/kg DM). At 07 30 h and 19 30 h, each animal was fed 350 g diet mixed with 1050 ml de-ionized water. Digesta were collected continuously and completely during a 12-h period after feeding. Mean hydrolysis rates of IP6 in the stomach as measured at the proximal duodenum of animals 1, 4, 5 and 6 were 9.0, 77.2 and 66.2% for diet 1, 2 and 3, respectively. Microbial phytase was much more effective in phytate hydrolysis than wheat phytase. Mean IP6 hydrolysis rates of the respective diets in the stomach and small intestine as measured at the distal ileum of animals 1, 2 and 3 were 19.0, 62.6 and 64.6% and were lower than treatment means of the stomach only. Differences existed between experimental animals with respect to their ability to hydrolyse IP6 in the stomach independent of the presence and source of dietary phytase. Considerable amounts of hydrolysis products occurred in both the duodenal and ileal digesta when diets 2 and 3 were fed; however, only traces were determined after ingestion of diet 1. Independent of dietary treatment, four IP5 isomers were detected, but in different amounts.