Animal Science Journal
Year:2020 | Volume:33 | Issue:126|Papers Count:15

The aim of the present study was to investigate the effect of imported semen under different selection indices on phenotypic changes of production traits in Holstein cattle population in various climates of Iran. In the present research, records of first lactation on milk yield, fat and protein percentage of 269786, 216850 and 270566 Holstein cattle derived from imported semen under different selection indices in cold, semi-cold, moderate and warm climates, were used. The data were collected by the Center of Breeding and Improvement of Livestock Production during 1993 to 2017. The data were analyzed using the General Linear Model (GLM) software SAS 9. 2. In cold, semi-cold, moderate and warm climates, the means of milk yield (kg) in the progenies of imported semen were estimated, 9597. 92, 9654. 46, 9718. 34 and 8985. 37, the means of fat percentage were estimated, 3. 13, 3. 07, 3. 08 and 3. 15 percent, and the means of protein percentage were estimated 3. 10, 3. 25, 3. 14, and 3. 16 percent, respectively. In the present study, the highest least square means of the phenotypic value of Holstein cattle derived from imported semen based on different selection indices in cold, semi-cold, moderate and warm climates were according to countries of France 2001-2011, Italy 1993-2001, Netherlands 2001-2006, France 2001-2011 for milk yield, Netherlands 1999-2000, United States 1987-1988, United States 1992-1993, and Canada 1998-2000 for fat percentage and Canada 1991-1992, France 2012-2013, Sweden 2008-2012 and Germany 2002-2007 for protein percentage, respectively.

In order to evaluate the effect of adding butyric acid to whole milk on growth performance and blood parameters of Holstein calves, 36 calves were used in a completely randomized design. The experimental treatments were: 1) control group without any additive (B0); 2) B0 + 4 grams per day of added butyric acid in milk (B4); and 3) B0 + 8 grams per day of added butyric acid in milk (B8). The calves had free access to feed and water during the experiment. Body weight at weaning and end of experiment tended to increase in B4 and B8 compared to B0 (P = 0. 08). Average daily gain was significantly (P < 0. 01) affected by treatment during the pre-weaning, so that B0 had the lowest daily gain, but no difference was observed between B4 and B8. The starter intake was less in B0 compared to the other two groups during pre-weaning period (P < 0. 01), post-weaning, (P = 0. 04) and throughout study (P < 0. 01), but there was no difference between B4 and B8. The serum concentrations of glucose, total protein and albumin within pre-weaning were not significantly different among treatments, but BHBA concentration was lower in B0 group than in other groups (P < 0. 01). There was no difference among treatments in terms of average fecal score. In general, for the first time, the results of this study showed that adding butyric acid to the whole milk can have positive effects on improving performance.

Today, genes in the mitochondrial genome are widely used as a strong genetic marker. The purpose of this study was to determine sequence of ND6 gene of the mitochondrial genome of Khazak chicken and investigate the phylogenetic relationship of this region of the genome with other chicken breeds and some fowls of around the world. 20 blood samples of wing vein were collected from Khazak chicken of Research Center of specific livestock of Sistan and Baluchestan province. DNA was extracted from whole blood. Then, the ND6 gene along with a portion of upstream and downstream tRNA (854 bp) was amplified from mitochondrial genome by specific primers in Polymerase Chain Reaction. Samples were sequenced after purification and genetic diversity was investigated within the population. After Download similar sequences of the other mitochondrial genome from the chicken breeds and some fowls of the NCBI, phylogenetic analysis was carried out. The results showed that there was no nucleotide difference between ND6 sequences of native Khazak chicken. The results of the phylogenetic tree from native Khazak chicken with other breeds showed that the highest genetic similarity was observed from this region of the mitochondrial genome of native Khazak chicken with HuangLang, Zhuxiang, Fiji, Philippines, Hengshan Yellow, Jinhu Wufeng and Red jungle fowl breeds which indicates that there are a high genetic relationship between the native Khazak chicken with the Japanese and Chinese (southeastern Asia) chicken breeds. The least genetic similarity of ND6 sequence from native Khazak chicken was observed with the Grus japonesis.

In order to evaluate the effects of using mixture of probiotic bacteria applied as a freeze dried or fresh culture on feed intake, weight gain, structural growth measurement and health, and blood metabolites, twenty four female Holstein calves were used in a completely randomized design. Calves after birth were randomly assigned into one of three treatments as follow: 1) control (without any additive), 2) calves received probiotic as a fresh culture and 3) calves received probiotic as freeze dried. Determination of starter intake and fecal scoring were done daily, and weighing and Structural growth measurements were recorded weekly. Blood samples were taken at the age of 25, 50 and 70 days old. Rumen fluid was collected 4 hours after morning feeding on 30, 60 and 70 days. The results showed that there were no differences among treatments on average weaning age and structural growth indices (p>0. 05). Neither fresh culture probiotic nor freeze dried probiotic had effect on initial, final and weaning weight (p>0. 05). There was no significant difference between treatments in terms of pH and ammoniacal nitrogen concentration (p>0. 05). Freeze dried or fresh culture of probiotic had no significant effect (p>0. 05) on blod metabolites (glucose, triglyserid, total protein, β _Hydroxybutyrate and albumin). Totally, the loss of predictable response resulted using of powder and liquid probioticson weaning calves performance can be attributed to good managerial and sanitary condition in weaning calves.

The objective of the present study was to characterize the growth pattern of morphometric traits of Isfahan native chickens. For conducting this research, 200 (112 males and 88 females) of Isfahan native chickens were reared for 12 weeks. At day 1, each chicken was weighed and marked with color plastic tags attached on the one leg and then weighed weekly. At weeks 3, 6, 9 and 12 morphometric traits such as breast width and length, thigh diameter and length, shank diameter and its length were measured. Flexible growth and fixed point of inflection functions were evaluated for their ability to describe the relationship between morphometric traits and age. Three non-linear growth functions (Gompertz, Logestic and Richards), were used for this purpose. Based on models fitting criteria and statistical parameters, all three models gave a good fit to the data (r2adj≤ 0. 90), but the Gompertz function gave the best fit to the data. The results indicated that male broilers had a higher final body size than the females. In general, males had higher asymptotic body size and lower growth rate than females. Females reached to maximum growth rate faster than males and had a lower body size in the inflection point. The correlation between body weight and morphometric traits at week 12 for both sexes were positive and significant (p < 0. 05) and the correlation values were moderate to high (0. 03

It has been shown that the occurrence of any changes in the function of DNMTs genes has a significant effect on both the embryo development and birth weight in mammals; therefore, the aim of the present study was to investigate the presence of DNA polymorphisms in the members of DNA methyl transferase superfamily and its relationship with birth weight in Sistani cattle’ s. Blood sampling was done randomly from 60 Sistani cows. DNA extraction was performed using phenol chloroform method. Candidate region for the presence of functional polymorphism within the DNMTs gene including the 114-bp fragment of the exon 33 of the DNMT1 gene, the 176-bp fragment of the intron 4 of the DNMT3a gene, and the 207-bp fragment in intron 3 of the DNMT3b gene were amplified by polymerase chain reaction. PCR-SSCP followed by polyacrylamide gels silver stain analysis was done to evaluate the presence of candidate mutations in target gens. The result analysis of all analyzed region did not show any mutations in the investigated DNMTs genes. Based on the results of this study, it seems that the lack of observation of genetic diversity in the studied regions could be related to the evolutionary selection against occurrence of specific mutations in the analyzed population. In general, based on the results of this study, analysis of genetic diversity in the studied genomic region may not be effective in identifying effective markers for breeding programs in Sistani cows.

Considering high tomato cultivation in Iran, the aim of this study was to investigate the replacement of different levels of tomato forage with alfalfa on the performance of Dalagh lambs. Therefore, it was carried out by using 16 lambs with a mean initial weight of 26. 5 ± 4. 2 with 4 treatments in completely randomized design. Tomato forage in three levels of 7, 14 and 21 percent replaced with alfalfa that with of control group formed experimental treatments. Daily feed was provided to lambs twice at, 8 and 16 hours and the feed residues were weighed in the end period. The lamb weight was measured every 14 days to measure growth. At the end of the course, stool and blood were performed to measure apparent digestion and blood metabolites. Lambs performance was affected by treatments (P <0. 05). Treatment 4 had the lowest daily gain at 187 gr and it has highest feed conversion ratio but no was significant difference between treatments 2, 3 with control. The use of tomato plants instead of alfalfa (more than 20%) resulted in an increase of 12 mg / dl of blood urea and 6 mg of cholesterol. There was no significant difference between experimental treatments in digestibility. Replacing tomato forage in a level of 14% with alfalfa in the final performance of lamb is economically beneficial, and trough this, by reducing the cost of breeding and reducing biological problems can be a beneficial nutritional resource.

Considering high tomato cultivation in Iran, the aim of this study was to investigate the replacement of different levels of tomato forage with alfalfa on the performance of Dalagh lambs. Therefore, it was carried out by using 16 lambs with a mean initial weight of 26. 5 ± 4. 2 with 4 treatments in completely randomized design. Tomato forage in three levels of 7, 14 and 21 percent replaced with alfalfa that with of control group formed experimental treatments. Daily feed was provided to lambs twice at, 8 and 16 hours and the feed residues were weighed in the end period. The lamb weight was measured every 14 days to measure growth. At the end of the course, stool and blood were performed to measure apparent digestion and blood metabolites. Lambs performance was affected by treatments (P <0. 05). Treatment 4 had the lowest daily gain at 187 gr and it has highest feed conversion ratio but no was significant difference between treatments 2, 3 with control. The use of tomato plants instead of alfalfa (more than 20%) resulted in an increase of 12 mg / dl of blood urea and 6 mg of cholesterol. There was no significant difference between experimental treatments in digestibility. Replacing tomato forage in a level of 14% with alfalfa in the final performance of lamb is economically beneficial, and trough this, by reducing the cost of breeding and reducing biological problems can be a beneficial nutritional resource.

This experiment was conducted to evaluate the effect of electron irradiation (EI) and fibrolytic enzyme (FE) on chemical composition and rumen degradation of palm leaves (PL) in a completely randomized design with factorial (2×2) arrangement include 2 levels of irradiation ( 150 and 300 KGy) and enzyme (1. 5 and 3 gr/kg dry matter of samples). For this purpose, at first 5 g of milled sample was incubated for 2, 4, 8, 12, 24, 48, 72 and 96 hours in the rumen of two Sistani bull with rumen fistula and degradability parameters estimated using nylon bags method. Based on the results, The EI and FE had no significant effect on dry matter, ether extract and crude protein. Treatment separately and together caused a significantly decreased (p < 0. 01) NDF and ADF. Also, the rapid and slowly degraded fraction and effective degradability of dry matter significantly increased with increasing irradiation dose and enzyme levels (p < 0. 01). EI along or with the FE had an effective role in improving the nutritional value and degradability of palm leaf. Considering that the best results were obtained in the simultaneous use of EI of 300 KGy and 3 g/kg of FE, the simultaneous use of these two levels were effective in order to improve the digestibility and degradability of palm leaves.

The aim of current research was to investigate the efficiency of dietary addition of ASRI1® and ASRI2® toxin binders and probiotic on performance, Aflatoxin concentrations of liver and muscle and intestinal microbial population of broiler chicks fed Aflatoxin-contaminated diets. A total of 420 one-day old Ross 308 broiler chicks were assigned in a completely randomized design to 7 treatments with 5 replications of 12 birds in each. The experimental treatments 1) non Aflatoxin contaminated diets or negative control (NC), 2) Aflatoxin-contaminated diets or positive control (PC), 3) PC diets containing ASRI1® toxin binder, 4) PC diet containing ASRI2® toxin binder, 5) PC diet containing probiotic, 6) PC diet containing probiotic+ ASRI1® toxin binder and 7) PC diet containing probiotic+ ASRI2® toxin binder. Performance was evaluated in periodical, Aflatoxin concentrations of liver and muscle at 28 and 42 days of age and intestinal microbial population at 42 days. The results showed body weight was significantly lower (p < 0. 05) and feed conversion ratio was significantly higher (p < 0. 05) in NC group when compared with PC group in grower and finisher periods. The harmful microbial population and Aflatoxin concentrations of liver and muscle were significantly higher (p < 0. 01) in PC group in comparison to NC group. However, the dietary addition of commercial toxin binders and probiotic especially their combination, significantly alleviated (p < 0. 05) Aflatoxin effects on performance, Aflatoxin concentrations of liver and muscle and intestinal microbial population.

In this research, effect of treating native rapeseed meal (NRSM) with microwave irradiation on chemical composition, glucosinolate, phytic acid, ruminal dry matter (DM) and crude protein (CP) degradability, metabolizable protein (MP) and in vitro CP digestibility of before and after irradiation were investigated. At first, moisture content of samples (three sample of 500 g) were increased to 250 g/kg. Then, were subjected to microwave irradiation at a power of 800 W for 2, 4 or 6 min. Chemical composition, phytic acid and glucosinolate contents of untreated and irradiated samples were determined by standard methods. Degradation kinetics of CP were determined according to in situ procedure. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used to monitor protein subfractions and the fate of true proteins of untreated and irradiated feed samples in the rumen. The results of experience showed that irradiation decreased the total glucosinolate and phytic acid content of NRSM (p < 0. 001). Ruminal disappearance of DM and CP in different incubation times linearly increased (p < 0. 05) as irradiation time increased. Based on results of this study, microwave irradiation more than 2 min decreased glucosinolate and phytic acid content and ruminal degradability of CP and increased by pass protein, in vitro CP digestibility and MP of NRSM and eventually, microwave irradiation was effective in improving nutritional value of NRSM for using in ruminant diet.

The aim of this study was to investigate the effect of lactation stage and numbers of parities on milk composition in Arabi ewe. Thirty Arabi ewes (10 ewe per each group from first, second and third parity) with average weight of 47 Kg in randomized design were used. After the parturition of ewes from each group, milk samples were collected every two weeks for two months to evaluate the milk composition. In the third parity ewes, the highest milk protein percent was related to the second month of lactation (p < 0. 05). In the first, second and third parity, milk fat percent was increased with lactation progress (p < 0. 05). The highest amount of total solid was belonged to ewes in their third parity in the 8th week of lactation (p < 0. 05). In the first parity ewes, the amount of total solid was fluctuating with lactation (p < 0. 05). In first and third parity of ewes, the percentage of milk lactose in the 8th week of lactation was higher than the previous stages of lactation. In the first parity ewes, pH increased with progress the lactation period (p < 0. 05). In general, physicochemical characteristics of Arabi ewe milk, except ash and density, were affected by parity and lactation stage.

Genomic information offers new possibilities to control the level of progeny inbreeding. Traditionally, mating plans constrain the inbreeding of predicted progeny by using a matrix of relationships among individuals. In this study aims to improve genetic gain and restrict the inbreeding level of progeny, a founder population, with effective population size 1000 and 1000 generations, was simulated using the QMSim program to generate linkage disequilibrium. Thereafter, 500 males and 500 females were used to generate a secondary 10-generation population, with 1000 individuals per generation and its corresponding phenotype and genotype in SNP terms. Five hundred sires and 500 dams from generation 1010 were randomly selected to create generation G0 and a trait with heritability of 0. 3 was simulated. The eight strategies consisting of two mating designs: minimum_inbreeding (minf) and random (rnd) and four relationship matrices as matrices of A, GRM, IBS and Weighted were used to estimate breeding value for ten generations. Comparison of strategies showed that type of mating designs and different relationship matrices had significant effect on amount of genetic gain, homozygosity and inbreeding (p < 0. 05). The type of relationship matrix affected the accuracy of predictions. In strategies with weighted matrix (Gweighted), average of genetic gain during 10 generations was less than strategies using A, GRM and IBS matrices. In strategies with random mating, inbreeding rate had increasing trend. Accuracy of selection (0. 63) in strategies with A matrix was lower than other strategies. In general,

In this study environmental effects, genetic and phenotypic trends for body weight traits in different age in Arabi Sheep estimated. In this study used a total of 11365 records on birth weight, 6930 records of weaning weight, 3275 records of 6 month weight, 2043 records of 9 month weight and 1750 records of 12 month weight. The data used in this study, collected during 1994-2015 in Khuzestan province. The breeding value of the animal were estimated by restricted maximum likelihood method. The SAS statistical software was used to evaluate the effect of environmental factors and Wombat software was employed to estimate animals breeding value. The SPSS software was used for estimation of the trends. Environmental factors such as birth year, Sex, birth type and age of Mather were significant on all traits and were fixed effects in model. Animal’ s age was introduced to the model as covariate. Estimation of direct genetic trend for birth weight, weaning weight, 6 month weight, 9 month weight and 12 month weight were as-0. 07,-17, 2, 1 and 1 gr per year respectively. The phenotypic trend for considered traits was respectively 5, 256, 76, 83 and 194 gr per year. It can be concluded that reduction of the average breeding value in the genetic trends and the oscillation in the phenotypic trend are due to reduction of recording accuracy and entering livestock with low breeding value to the herd or negative impact of environmental factors on the production potential of livestock.

The optimization of the reference population in genomic evaluation plays an important role in livestock breeding, because of its potential impact on the accuracy of estimating the marker effects and genomic breeding values. In the present study, seven different train set selection methods including selection of all, selection of the highest and lowest performances, random selection, selection of individuals with the most and least marker and QTL similarity were evaluated. In genome wide association study selection of all as train set detected common SNPs which make a high variation on the trait. However selective train set was just reported rare SNPs with a major effect on the trait. In genomic selection simultaneous use of high-density markers and selective train set in comparison with low-density and selection of all as train set reduced accuracy, but did not change the ranking of animals. There was also an interaction between train set selection method and generation (P≤ 0. 0134) as well as the linkage disequilibrium (P≤ 2e-16). In general, selection of all animals as a train set resulted in higher accuracy compared to six selective train set methods. There were no differences between the methods of selecting train set in populations with a low effective size (r2 = 0. 255, Ne =100), but in populations with a high effective size (r2 = 0. 086, Ne =400) methods, with different accuracy predicted genomic breeding values. The highest and lowest accuracy were respectively belonged to most QTL and marker similarity methods.