Effect of Hoodia gordonii meal supplementation at finisher stage on productivity and carcass characteristics of Ross 308 broiler chickens

Two experiments were conducted to evaluate the effect of Hoodia gordonii meal supplementation at finisher stage on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment examined the effect of level of Hoodia gordonii meal supplementation at finisher stage (30 to 42 days of age) on productivity and carcass characteristics of chickens. Level of Hoodia gordonii meal supplementation had no effect (P > 0.05) on diet intake, growth rate, feed conversion ratio and live weight of chickens. Daily supplementation with 300 mg of Hoodia gordonii meal reduced (P < 0.05) fat pad weights by 40 % in broiler chickens The second experiment examined the effect of Hoodia gordonii meal supplementation interval on the productivity and carcass characteristics of broiler chickens. Hoodia gordonii meal supplementation interval had no effect (P > 0.05) on feed intake, growth rate, live weight, feed conversion ratio and all carcass characteristics except fat pad of broiler chickens. Daily supplementation with 300 mg of Hoodia gordonii meal/bird reduced fat pad weights of the chickens by 18 %. This could not be explained in terms of differences in feed intake, digestibility, or growth rate.     

三氯化铬对肉仔鸡生产性能和胴体性能的影响

本试验研究日粮中添加三氯化铬(CrCl3)对肉仔鸡生产性能和胴体性能的影响.选用144只1日龄体重均一、健康的艾维菌肉仔鸡,随机分成6组,每组设3个重复.试验期分别饲喂6种不同饲粮1组为对照组,喂基础日粮;2～6组为三氯化铬组,分别在基础日粮中添加0.5、1.0、1.5、2.0、2.5 mg/kg三氯化铬.试验结果表明日粮中添加1.5～2.0mg/kg三氯化铬均能显著提高肉仔鸡增重(P＜0.05),显著改善肉仔鸡的饲料效率和胴体性状(P＜0.05).     

Effects of Astragalus membranaceus on growth performance,carcass characteristics,and antioxidant status of broiler chickens

Abstract

An experiment was conducted using 720 one-day-old Arbor Acres broiler chickens to evaluate the effects of Astragalus membranaceus root powder (AMP), Astragalus polysaccharides (APS) on growth performance, carcass characteristics, and antioxidant enzymes, and metabolites of blood and liver in broiler chickens. The six dietary treatments included a control that was a corn–soybean meal basal diet; basal diet supplemented with 120 mg/kg antibiotic; 350 mg/kg APS; or 5000, 10,000, or 15,000 mg/kg diet of AMP. Supplementation of 10,000 mg/kg AMP increased average daily gain and feed conversion rate of broilers in grower period (22–42 d) and over the entire experiment compared to basic diet. Responses of antioxidant status to dietary APS and AMP varied depending on the age of the broilers. Beneficial effects of AMP on growth and feed utilization of broilers could be obtained by inclusion of AMP at the rate of 10,000 mg/kg diet.     

Influence of stocking density on the performance, carcass characteristics and selected welfare indicators of broiler chickens

AIM: To compare the effects of four stocking densities (5, 10, 15 or 20 birds per m2) on the performance, carcass characteristics and selected welfare indicators of broiler chickens. METHODS: A total of 756 day-old male broiler chicks were assigned as six replicates of 13, 25, 38 and 50 birds per pen, to stocking densities of 2,000, 1,000, 667 and 500 cm2 floor space per bird, respectively. The birds were housed in floor pens in an environmentally controlled room. Normal commercial diets were fed ad libitum and fresh water was freely available throughout the 5-week study period. Liveweights of birds and feed intake were recorded at weekly intervals. Data on carcass parameters and welfare indicators (moisture, gait scores, feather scores, breast and hip lesions, and foot pad and hock burns) were obtained on Day 35. Adrenal glands were removed at slaughter, weighed and examined histologically to determine the total proportion of cortical and medullary tissues. RESULTS: During the study, the birds at the lowest density grew faster (p<0.001-0.01) and consumed more (p<0.001- 0.01) feed than those at the other three stocking densities. The liveweight gains and feed intake of birds reared at densities of 10, 15 and 20 birds per m2 were similar (p=0.11-0.83 and p=0.17-0.57, respectively). Stocking density had no influence on the feed/weight gain, mortality or carcass characteristics. No breast or hip lesions were observed in carcasses from any of the groups. The weight and structure of the adrenal glands were similar across all groups although the staining of medullary tissue of birds was most intense in the highest stocking density group. As stocking density increased, so did moisture and gait score, hock and foot pad burn scores, and the feather score was adversely affected. CONCLUSIONS: The data showed that the relationship between stocking density and productivity traits was not linear in nature, in accordance with other studies. Under the conditions of the current study, the performance, mortality and carcass characteristics of broilers grown at densities of 10, 15 and 20 birds per m2 were similar. There were some welfare implications at high population densities as indicated by adverse effects on litter quality, gait scores and the incidence of hock and foot pad burns.     

Dietary supplementation with acidifiers improves the growth performance,meat quality and intestinal health of broiler chickens

This experiment was conducted to study the effects of dietary supplementation with acidifiers on the growth performance, meat quality, and intestinal health of broiler chickens. A total of 648 male Arbor Acres broiler chickens at 1 d old were randomly divided into 6 groups, and each group consisted of 6 replicates with 18 broilers per replicate. The dietary treatments were as follows: negative control (NC, the basal diet), NC + antibiotic (enramycin, 8 mg/kg, positive control [PC]), NC + phosphoric acid (PA, 0.1, 0.2, and 0.3 g/kg), and NC + lactic acid (LA, 0.3 g/kg). The feeding trial lasted for 42 d. The results showed that the feed-to-gain ratio of the NC + acidifier groups was lower than that of the NC and PC groups from 1 to 42 d (P < 0.05). Compared with the values in the NC group, the pH of breast muscle was significantly higher in the NC + PA (0.2 g/kg) and LA (0.3 g/kg) groups (P < 0.05), and the cooking loss was lower in the breast muscle of the NC + PA (0.1 g/kg) and LA (0.3 g/kg) groups (P < 0.05). In addition, the shear force of the breast muscle and thigh muscle and the pH value in the crop, gizzard and duodenum of the antibiotic and acidifier groups were significantly decreased (P < 0.05). Moreover, the trypsin, chymotrypsin, and lipase activities of the duodenum in the NC + PA (0.2 and 0.3 g/kg) groups, as well as the villus height-to-crypt depth (VH:CD) ratio of the duodenum in the NC + PA (0.1 g/kg) group was significantly greater (P < 0.05) compared with those in the NC group. Meanwhile, the number of total aerobic bacteria, Escherichia coli and Salmonella in the cecum of the NC + PA (0.1 g/kg) and LA (0.3 g/kg) groups were decreased (P < 0.05). Collectively, diet supplementation with acidifiers could improve the growth performance, meat quality, and intestinal health of broilers, in which the effects of PA (0.1 g/kg and 0.2 g/kg) are better than the other supplementations.     

The effects of antibiotic,probiotic, organic acid,vitamin C,and Echinacea purpurea extract on performance,carcass characteristics,blood chemistry,microbiota, and immunity of broiler chickens

The present context investigated the comparative study on the supplementation of antibiotic, probiotic, organic acid, vitamin C, and herbal extract after vaccination into drinking water and their effects on performance, carcass quality, blood biochemical parameters, immune system, and intestinal flora in broiler chicks for 42 days. A total of 420 one-day-old male broiler chicks (Ross 308) were randomly assigned into 7 treatments with 3 replicates (pens) per treatment and 20 male chicks for each replicate (pen). The experimental treatments consisted of drinking water (control, without additive); drinking water + antibiotic sulfamet; drinking water + C-Vet-50; drinking water + antibiotic sulfamet + C-Vet-50; drinking water + probiotic Primalac; drinking water + butyric acid; and drinking water + extract of Echinacea purpurea Moench (coneflower). There were no differences observed among the treatments for feed intake, but during the whole experimental period, the highest body weight gain was found in the chicks fed with drinking water + antibiotic sulfamet + 50 cc vitamin C (P < 0.05). There were no differences (P > 0.05) observed among the treatments for feed conversion ratio (P > 0.05). Moreover, there were no differences reported among treatments for carcass characteristics at the end of the experiment. Among the treatments, drinking water + 50 cc vitamin C, and drinking water + extract of E. purpurea reduced (P < 0.05) the levels of cholesterol, triglycerides, and low-density lipoproteins. Drinking water + 50 cc vitamin C, drinking water + Primalac, and drinking water + extract of E. purpurea increased (P < 0.05) the lymphocytes count and decreased the heterophils count and heterophil:lymphocyte ratio. The highest Escherichia coli count and lowest Lactobacillus count in ileal content of the broilers were observed in the control group (P < 0.05). The additives used in this study may be incorporated in the drinking water of broiler chickens as growth promoters and for improved performance. A further, wider supplementation study is required to understand the performance, immune system, variation in the intestinal microbial counts, and any other possible alteration in the intestinal biota of the broilers.     

Effects of dietary medium-chain fatty acids on performance,carcass characteristics,and some serum parameters of broiler chickens

1. This study aimed to evaluate the effects of dietary medium-chain fatty acids (MCFAs) on the performance, carcass characteristics, and some serum parameters of broiler chickens.

2. A total of 176 one-day-old male broiler chicks (Ross 308) were assigned to four treatments including control treatment (basal diet), 0.1% MCFA, 0.2% MCFA, and 0.3% MCFA treatments according to a completely randomised design. Each treatment consisted of 4 replicates with 11 chicks for each replicate. In MCFA treatments, the amounts of MCFAs were added to basal diet as a substitution of soybean oil.

3. There were not any significant differences in body weight, feed intake, and feed conversion ratio among the treatments in different stages of the experiment. However, MCFA treatments had a lower abdominal fat and a higher breast yield compared to control treatment.

4. Blood glucose, cholesterol, and low-density lipoprotein (LDL)-cholesterol concentrations were significantly decreased, but blood high-density lipoprotein (HDL)-cholesterol concentration was significantly increased in the MCFA treatments compared to the control treatment.

5. These results indicate that dietary MCFA has a positive effect on the health and productivity of broiler chickens.     

Influence of pre‐press solvent‐extracted cottonseed meal supplemented with exogenous enzyme and digestible lysine on performance,digestibility, carcass and immunity responses of broiler chickens

The response of broiler chickens to two levels of endo‐1,4‐β xylanase (EC 3.2.1.8) and endo‐1,3‐β glucanase (EC 3.2.1.6) combination (with and without), three levels of digestible lysine (0.8%, 0.9% and 1.0% with the applicability of ideal protein concept) and two levels of cottonseed meal (CSM; 20% and 30%) were evaluated in 2 × 3 × 2 factorial arrangement. A total of 2448 male Hubbard broiler chicks were fed on practical vegetable‐based mash diets having 2750 kcal metabolizable energy (ME) per kg and 18.5% crude protein (CP) from the age of day 1 to 42. The supplemental enzyme had minimum 1100 units of endo‐1,4‐β xylanase and 100 units of endo‐1,3‐β glucanase/kg of finished diet. The addition of CSM at 30% resulted in increasing arginine to lysine ratio. A decrease in dressing and breast percentages were observed by the addition of 30% CSM. The digestible lysine at 1.0% decreased the body weight (BW) gain and lowered the mortality during day 1 to 21 whereas the BW gain and feed:gain ratio were unaffected among the three digestible lysine levels during day 1 to 42. The antibody titres against Newcastle and infectious bursal disease viruses were improved with the increasing levels of digestible lysine. The enzyme supplementation improved the apparent ME and digestibility coefficient of nitrogen when it was used with 30% CSM. No effect of enzyme, lysine, CSM or their interactions was observed on serum iron, gizzard and liver weights or abdominal fat percentage. The results showed that increasing digestible lysine improved the antibody titre but did not improve the growth performance and carcass characteristics; supplemental enzyme failed to show any improvement in performance of birds fed on CSM‐based diets.     

Growth performance,carcass characteristics,meat quality and serum profile of broiler chicks fed on housefly maggot meal as a replacement of soybean meal

A study was conducted to invesstigate the housefly maggot meal (HMM) as an alternative protein source to replace the soybean meal in broiler chick's diet. A total of 720 1-day-old male broiler chicks were divided into three groups and fed diets formulated with HMM to replace soybean meal at the rate of 0%, 4% and 8%. The study lasted for 42 days in two phases. Results showed that HMM addition did not markedly affect body weight, average daily body weight gain and average daily feed intake of the broiler chicks. Feed conversion ratio increased linearly (1–21 days) in starter or quadratically (22–42 days) in the grower phase. HMM non-significantly increased the feed intake and body weight during the grower phase. Slight changes were observed for decrease of blood biochemical indices in the platelets (day 21), and alkaline phosphatase and lysozyme (day 42), and increase for red blood cells, packed cell volume, total protein and uric acid on day 42; however, the fluctuations were within the physiological range. Non-significant effects were observed for carcass composition and meat quality, except that HMM numerically reduced the shear force of breast muscle (linear, p = .058). These results are the strong evidence that HMM can be used as an alternative protein source at 8% in broiler chick's diet without any adverse effect on chick's performance.     

The effect of cimaterol and its withdrawal on carcass composition and meat tenderness of broiler chickens.

To examine the effects of cimaterol (CIM) and its withdrawal on meat tenderness and carcass composition, 21-d-old broiler chickens (n = 288) were randomly assigned to one of nine treatments. For Treatments 1 through 6, birds were fed a control diet or a diet containing 1 ppm CIM until slaughter at 35, 42, or 49 d of age. Treatments 7 and 8 consisted of birds fed the CIM diet for 14 d and then withdrawn from CIM for either 7 or 14 d before slaughter (42 or 49 d of age). In Treatment 9, birds were fed the CIM diet to 42 d of age, then withdrawn from CIM for 7 d. Breast muscle (BM) weight, leg muscle (LM) weight, whole body weight, and BM and LM cathepsin B and L activities were obtained on 12 birds/treatment. Body, LM and BM composition and BM shear values were obtained on 12 additional birds/treatment. Eight birds/treatment were used to balance the number of birds per pen. Leg muscle weight, as a percentage of whole body weight, was elevated in CIM-fed birds at all ages, and BM percentage was greater at 35 d of age (P less than .05). Leg muscle fat percentage was reduced at 35 and 42 d of age (P less than .05), and LM protein was elevated at 42 and 49 d of age (P less than .05) in CIM-fed birds. Percentage of protein in the BM of CIM-fed birds was elevated at 35 and 42 d of age. Protein content of the whole body was also increased at 35 d of age. Shear values were higher in 42- and 49-d-old CIM-fed birds.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of genotype and population density on growth performance,carcass characteristics,and cost-benefits of broiler chickens in north central Nigeria

The influence of genotype and stocking densities on growth performance, carcass qualities, and cost-benefits of broilers were examined in a 28-day trial. Two hundred and seven 4-week-old birds each of Anak Titan and Arbor Acre hybrid broiler types were randomly assigned to three stocking density treatments of 8.3, 11.1, and 14.3 birds/m² in a 2 × 3 factorial arrangement. Final body weight, average weekly body weight and average weekly feed intake were affected (P < 0.05) by strain, with higher means recorded for Arbor Acres. However, average weekly body weight gain and feed conversion ratio were similar (P > 0.05) in both genetic groups. The effect of placement density on some growth parameters did not follow a linear trend. Arbor Acres had significantly (P < 0.05) higher relative (%) fasted body, carcass, back, neck, and wing weights compared to Anak Titans. Housing density effect (P < 0.05) was observed for relative (%) fasted body, shank, and wing weights of birds. However, the relative weights of visceral organs of birds were not significantly (P > 0.05) influenced by genotype and housing density. The economic analysis revealed that higher gross margin was recorded for Arbor Acres compared to Anak Titans (€2.76 versus €2.19; P < 0.05, respectively). Conversely, stocking rate did not exert any influence (P > 0.05) on profit margin. Genotype × stocking density interaction effect was significant for some of the carcass indices investigated. It is concluded that under sub-humid conditions of a tropical environment, the use of Arbor Acre genetic type as well as a placement density of 14.3 birds/m² appeared to be more profitable.     

Dietary supplementation of phenyllactic acid on growth performance,immune response,cecal microbial population,and meat quality attributes of broiler chickens

A total of 750 one-day-old male broiler chicks were randomly fed 5 dietary treatments with 5 replicate pens per treatment. The 5 dietary treatments fed for 42 d were a corn-soybean meal basal diet without antibiotic (control); a mixture of 10 ppm of avilamycin + 60 ppm of salinomycin as antibiotic growth promoters (AGP); 0.1% phenyllactic acid (PLA); 0.2% PLA; and 0.4% PLA. The BW gain and FE were significantly improved in AGP and PLA groups compared with control group. The white blood cells and heterophil counts were significantly higher in the PLA-supplemented groups compared with AGP and control groups, but the heterophil-to-lymphocyte ratio was lower in the control group than other groups. The plasma IgY concentration was significantly increased in birds fed PLA-supplemented diets, but the plasma IgA and IgM concentrations were not different among the treatment groups. In addition, the antibody titer against Newcastle disease virus was significantly higher in PLA-treated compared with control and AGP-treated groups. Neither PLA nor AGP treatments affected the cecal aerobes andSalmonella content; however, cecalLactobacillus population increased in chickens fed 0.1% PLA, and total coliform bacteria population significantly decreased in chickens fed various levels of PLA and AGP. Dietary supplementation of PLA did not affect the pH, lightness, and redness of breast meat, but the water-holding capacity and shear force value increased and the yellowness decreased significantly when birds were fed PLA. It was concluded that dietary supplementation of 0.1 and 0.2% PLA improves BW gain and FE of broiler chickens. In addition, PLA supplementation increases the immune characteristics and the number of lactic acid bacteria, decreases the number of coliform bacteria, and improves the meat quality attributes of broiler chickens. Thus, dietary PLA could be a viable alternative to antibiotics in broiler diets.     

The effect of different dietary levels of maize germ meal on the performance of broiler chickens

In the first experiment chicks were given pelleted diets containing 0, 10, 25 or 50% maize germ meal from 1 day of age for 4 weeks; from 4 to 8 weeks of age the birds were given a common finisher diet. In the second experiment the maize germ meal was used in broiler finisher diets at levels of 0, 10, 20 or 30%. In the third experiment, the maize germ was incorporated in diets for the entire 8‐week period. It involved three levels of the maize germ (0, 10 or 20%) in the diets given during the rearing period and four levels (0, 10, 20 or 30 %) in the diets given from 4 to 8 weeks, the experiment having a 3 x 4 factorial design.

It is concluded that maize germ meal can successfully be included in broiler diets at levels up to 20% during the first 4 weeks and up to 30 % during the second 4 weeks.     

Effect of sodium bentonite on the performance and blood variables of broiler chickens intoxicated with aflatoxins.

1. This study was conducted to evaluate the protective effect of natural sodium bentonite (NaB) in the prevention of toxic effects of aflatoxins. Five hundred and twenty-eight 1-d-old Ross male broiler chickens were housed in pens (22 chickens per pen) for 42 d. There were 3 inclusion rates of NaB (0, 2.5, and 5 g/kg) and 2 of aflatoxins (0 and 3 mg/kg food). Each treatment had 4 replicates of 22 chickens. 2. All chickens treated with aflatoxin and without bentonite were adversely affected. NaB treatment at 5.0 g/kg improved body weights at 42 d of age by 31.3%, increased food intake by 23.8% and improved productive efficiency by 40.1%. Weights of liver, heart, pancreas and crop and biochemical variables were not affected by dietary NaB. However, serum phosphorous concentration was reduced by 30% compared with chickens that received aflatoxin. 3. NaB caused no adverse effects on chickens that did not receive aflatoxin. 4. It is concluded that NaB at pH 7.9 partially neutralises the effects of aflatoxins on broiler chickens when included at 5.0 g/kg in the diet.     

Dietary supplementation of Zingiber officinale and Zingiber zerumbet to heat‐stressed broiler chickens and its effect on heat shock protein 70 expression,blood parameters and body temperature

The present study was conducted to assess the effects of dietary supplementation of Zingiber officinale and Zingiber zerumbet and to heat‐stressed broiler chickens on heat shock protein (HSP) 70 density, plasma corticosterone concentration (CORT), heterophil to lymphocyte ratio (HLR) and body temperature. Beginning from day 28, chicks were divided into five dietary groups: (i) basal diet (control), (ii) basal diet +1%Z. zerumbet powder (ZZ1%), (iii) basal diet +2%Z. zerumbet powder (ZZ2%), (iv) basal diet +1%Z. officinale powder (ZO1%) and (v) basal diet +2%Z. officinale powder (ZO2%). From day 35–42, heat stress was induced by exposing birds to 38 ± 1 °C and 80% RH for 2 h/day. Irrespective of diet, heat challenge elevated HSP70 expression, CORT and HLR on day 42. On day 42, following heat challenge, the ZZ1% birds showed lower body temperatures than those of control, ZO1% and ZO2%. Neither CORT nor HLR was significantly affected by diet. The ZO2% and ZZ2% diets enhanced HSP70 expression when compared to the control groups. We concluded that dietary supplementation of Z. officinale and Z. zerumbet powder may induce HSP70 reaction in broiler chickens exposed to heat stress.     

米曲霉和枯草芽孢杆菌对羽毛粉降解效果研究

为提高羽毛粉的营养价值,通过测定蛋白酶活力和羽毛粉中可溶性蛋白含量,对米曲霉和枯草芽孢杆菌对羽毛粉的降解效果进行研究。结果表明:发酵72 h后,米曲霉产蛋白酶活力达到3 256.61 U/g(P<0.05),枯草芽孢杆菌产蛋白酶活力达到690.03 U/g(P<0.05)。米曲霉发酵羽毛粉48 h,可溶性蛋白含量由最初的2.21 mg/g提高到362.07 mg/g(P<0.05)。结果显示,米曲霉和枯草芽孢杆菌均可对羽毛粉起到降解作用,其中米曲霉的降解效果更为明显。