Research On Animal Production
Year:2012 | Volume:3 | Issue:5|Papers Count:7

In the present research, performance records of Fars native chicken from years 1988 to 2002 were used. Studied traits were body weight at 12 weeks (BW12), age at sexual maturity (ASM) egg weight (EW) and egg number (EN). Variance Components and genetic, phenotype and environmental correlations were estimated using restriction maximum likelihood (REML) and Bayesian analysis method based on Gibbs sampling technique under univariate and multivariate animal model. Univariate estimation of heritabilities with REML for ASM, EW, EN and BW12 were 0.53, 0.63, 0.33 and 0.53, while, with multivariate model these values were 0.51, 0.64, 0.33 and 0.53, respectively.Heritabilities estimates with Bayesian analysis in univariate model for ASM, EW, EN and BW12 were 0.53, 0.63, 0.34 and 0.55, respectively, while with multivariate model were these values 0.56, 0.58, 0.33 and 0.55, respectively. Genetic and environmental correlations between BW12 and ASM using both methods were negative but phenotypic correlation was positive. Genetic, environmental and phenotypic correlations between BW12 and EW and EN with both methods were positive. The estimates between W12 and EW with REML were 0.5, 0.15 and 0.36, whereas with Bayesian were 0.43, 0.26 and 0.28, respectively. Those estimates between BW12 and EN with REML were 0.03, 0.15 and 0.1, respectively, whereas with Bayesian were 0.19, 0.23 and 0.19, respectively. The above mentioned correlations between ASM and EN were high and negative using both methods. It can be concluded that the estimation of the parameters evalvated using with these two methods are close together.

An experiment was conducted to evaluate the effect of replacement of different levels of broken rice with corn on performance of broiler chicken in grower period. Four hundred one-day-old broiler chicks (Ross 308) were used in a completely randomized design with 5 treatments and 4 replicates for 42 days. Five treatments included control diet and different levels of broken rice 10, 20, 30 and 40 instead of corn meal diets (R1, R2, R3 and R4 respectively). Diets were calculated to be isocaloric and isonitrogenous and formulated according to National Research Council (NRC, 1994) recommendation. Body weight gain, feed conversion ratio and feed intake were measured weekly. Highest body weight were observed in control, R1 and R2 diets in the 4th, 5th and 6th weeks of experiment (P<0.05).Results of this experiment showed that using different levels of broken rice had significant effect on live weight, feed intake and body weight gain (P<0.05). The results showed that broken rice can be included in broiler diet up to 20% without any advers affect on growth performance.

An experiment was conducted to evaluate the effect of L-glutamine (Gln) supplementation on growth performance and small intestinal morphology of broiler chickens. One hundred and ninety two day-old male broilers (Ross 308) were used in a completely randomized design with 4 treatments and 4 replicates with 12 birds in each replicate. Four experimental diets were formulated to be isonitrogenous and isocaloric with different levels (0, 0.5, 1.0 and 1.5%) of Gln supplementation and were fed for the first 21 days of rearing period. Results showed that body weight and average daily weight gain increased in the birds consumed 1% Gln supplemented diet compared to the control birds fed a standard corn-SBM diet (P<0.05). Birds fed diets supplemented with 1 or 1.5% Gln had heavier duodenum and jejunum relative weight compared to the control birds (P<0.05).Morphological assays showed that villus height and villus surface area of the duodenum and jejunum increased as 1 or 1.5% Gln was supplemented in broiler diets comparing to the control group (P<0.05). Goblet cells density was not significantly affected by dietary Gln inclusion. The results of this study indicated that adding 1% Gln to diet for the first 21 days of rearing period improved growth performance and small intestinal morphology of broiler chickens.

An experiment was conducted to study the effect of L-carnitine (0, 125 mg/kg) in diets with different sources of fat (Soybean oil, tallow, blend of soybean and tallow) on performance, body composition and blood parameters on 108 broiler chicks (Ross 308) in a factorial arrangement (2´3) with completely randomized design with 6 treatments, 3 replicates and 6 chicks in each replicates. During the experiment (11-28 d) feed intake, body weight gain feed conversion ratio body composition and blood parameters were measured. Based on the results of this experiment, different sources of fat had not significant effect on chick performance. However, carcass fat decreased significantly in chicks fed with diets supplemented with soybean oil but carcass Protein and fat percentage were not affected by different sources and levels of fat and L-carnitine. Lcarnitine supplementation in diet had not significant effect on body weight, feed intake and feed conversion ratio, but it significantly decreased total carcass fat. Adding of soybean oil to diet, significantly reduced, blood glucose, cholesterol and LDL concentration compared with diets containing tallow or a mixture of tallow and soybean oil, while triglyceride, HDL and VLDL concentrations increased. Adding L-carnitine to diets containing soybean oil reduced carcasses fat and glucose, cholesterol and LDL concentrations compared with diets containing tallow or a mixture of tallow and soybean oil in Ross 308 broiler chickens.

This experiment was conducted to evaluate the effect of Ziziphora clinopodioides L. on performance, blood biochemical parameters and cells of broiler chickens. The experiment was conducted in a completely randomized design with 300 broiler chickens (Ross 306) in 5 treatments and 3 replicates (with 20 chicks per replicate) from day 1 to day 42 of age. The experimental groups were 1), control without using medicinal plant 2), 0.5% Ziziphora clinopodioides L., 3), 1% Ziziphora clinopodioides L., 4) 1.5% Ziziphora clinopodioides L., 5), 2% Ziziphora clinopodioides L. The results showed that the addition of Ziziphora clinopodioides at 1.5 and 2% significantly increased feed intake in grower period and adding 1% Ziziphora clinopodioides to diet decreased feed conversion ratio, when compared to control group. In comparison to control diet, supplementation of 1% Ziziphora clinopodioides significantly decreased abdominal fat and increased breast percentage (p<0.05). There were not significant (P>0.05) differences in dressing, thigh and relative weight of liver, gizzard and small intestine. The addition of Ziziphora clinopodioides had not significant effect on cholesterol and triglyceride concentrations and heterophil and lymphocyte percentage. The overall results showed that using of 1% of Ziziphora clinopodioides medicinal plant could be helpful in improving performance and immunity parameters of broiler chickens.

The aim of this study was investigation of monthly changes of semen characteristics, length and scrotal circumference in Dallagh rams. Semen samples were collected from four healthy and mature rams of 3-4 years old with an average body weight of 45±5 kg with an electro ejaculator in once three weeks since June to November 2008. Results showed that the effect of months on scrotal circumference, testicular length, viability, motility, wave motion and minor defects spermatozoa were not significant (p>0.05).Maximum testicular length, motility and the minimum minor defect were observed in October while the maximum viability and scrotal circumference were observed in July.Effect of months on major defects was significant (p<0.05) and the maximum major defects were observed in June. The effect of months on testis and semen characteristics were not significant. It can be concluded that the reproductive activities of Dallagh rams were not affect by season probably and they had reproductive capability throughout months of experiment. Therefore it seems Dallagh rams have lower sensitivity to changes of day length and breeding season and canbe used for mating ewes in favorable time until lambing occur in suitable season.

To investigate the effects of feed restriction and Coenzyme Q10 supplementation on incidence of ascites and immune system in broilers, a factorial arrangement with completely randomized design with two levels of CoQ10 (0, 20 mg/kg of diet) and three levels of feed restriction (0, 10 and 20 %) was carried out. Six hundreds 1-d-old Arian broiler chicks were randomly allocated into 6 groups with 5 replicates and 20 chicks in each replicate. From d 15, the diets were supplemented with CoQ10 at levels of 0 and 20mg/kg. During the experimental period (42 days) chick mortality for ascites problem were investigated. Also, the RV/TV ratio, total red blood cell (RBC), hematocrit (PCV), hemoglobin (Hb), leukocyte differential counts (including heterophils (H), lymphocytes (L), H: L ratio) were investigated. In this experiment SRBC response, IgG and IgM were investigated as immune responses. According to results, RV/TV ratio, hematocrits, hemoglobin and total red blood cell number were not affected by feed restriction and CoQ10 (p>0.05). Feed restriction had no positive effect on SRBC response but it was affected by CoQ10 which found to be significant (p<0.07). Feed restriction and CoQ10 had not significant effect on immunoglobulin M and G (p>0.05). White blood cells, lymphocytes, hetrophils and also hetrophil to lymphocytes ratio were not affected by feed restriction and CoQ10 (p>0.05).