مجله علوم دامی ایران
سال چهل و هشتم شماره 4 (زمستان 1396)

The aim of the present study was to evaluate the incidence of liver abscess in lactating and dry Holstein cows and its effect on some blood parameters and histology of hepatocytes. The liver of 577 lactating and dry Holstein cows at the time of slaughter in two abattoirs in Iran were examined. Blood collection from cows was carried out at the time of slaughter. Sixty healthy cows, i.e., the same number of cows with liver abscesses (which had no problem in terms of autopsy and splanchnic checking), were considered as control group according to herd and number of gestation. Immediately after slaughter, the livers of the cows was divided into 4 groups of liver without abscess score 0, liver with one or two small abscesses or scars; score A, liver with two to four well-organized abscesses; score A, and liver with one or more large open abscesses, with or without adhesions; score A. The slaughterhouse survey showed that, 10.4% (60 cows) had liver abscesses (25, 31.7 and 43.3 % for A-, A and A). Data from histological studies showed that in livers with abscesses in compare to healthy livers, natural form of hepatocytes close to sinusoids in liver with abscesses had changed, parts of the affected tissue showed necrosis and the numbers of Kupffer cells were increased. The concentration of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma glutamyltransferase (GGT) in the blood serum of cattle with liver abscesses with A, A and A scores were higher than that of healthy cows (P≤0.01), while the concentration of creatine kinase (CK) in the cows affected by the abscess was lower than the healthy group (P≤0.01). Cows with liver abscesses with scores A-, A and A had lower concentrations of albumin and serum cholesterol than healthy cows (P≤0.01). The results of this study showed that the higher concentrations of liver enzymes and low blood concentrations of albumin and cholestrol in cows with liver abscesses may be due to the destruction of liver cells and inflammation. In conclusion, some blood parameters can be used as an indicator for assessing the status of liver abscess.

At this study, with using from univariate and multivariate Econometrics Models of time series techniques, the annual prices from 2015 to 2020 for Iran and from 2014 to 2020 for world was predicted. The Iran data related to the chicken price, corn price, soybean meal price and chicken production rate from 1990 to 2014 were provided from Ministry of Agriculture Iran, State Livestock Affairs Logistics (S.L.A.L) Inc. and Central Bank of the Islamic Republic of Iran and the world data are provided from FAO STAT for the year 1961-2013. The most appropriate model for fitness and prediction of chicken meat in Iran is the autoregressive moving average model (ARMAX (3,5)), with the in-sample and out of sample of predicting error are 2.12 and 4.7 percent and in world, autoregressive moving average model (ARMA (1,13)) with the in-sample and out of sample of predicting error are 4.34 and 3.91 percent, according to mean absolute percent error criterion. Also the results of vector error correction models (VECM) estimation have shown one unit increasing in the ratio of the price of corn to soy and the amount of meat production in Iran, can increase 7.59 and 3.29 percent in Iran chicken meat and one unit increasing in world price of corn and the amount of world production of chicken meat can cause increase equal 0.31, 0.46 and 0.64 percent in chicken meat world price.

To investigate effects of dietary supplemention with betaine and injection of vitamin B12 during the transition period on profile of milk fatty acids, 32 Holstein dairy cows were used. Experimental treatments included control (a basal diet without any supplementation; CC), CB (supplemnting with 50 g of rumen unprotected betaine per day per head during the transition period), BC (injection of 0.5 mg vitamin B12 in a 10-days interval) and CC (supplemnting with 50 g of unprotected betaine per day per head plus injection of 0.5 mg vitamin B12 in a 10-days interval. The CB and BB significantly increased denovo synthesis of fatty acids in mammary gland and milk fat concentration of saturated fatty acids (P 0.05). Milk fat concentration of polyunsaturated fatty acids was higher in cows recived CB than in BC and BB cows, but similar to CC cows. Experimental treatments had no effect on perentage of milk fat and plasma concentration of glucose (P>0.05). In conclusion, to inceraese denovo synthesis of fatty acids in mammary glands intarmuscualr injection of vitamin B12 in transition cows is recommended.

This study was conducted to production and evaluation of encapsulated fish oil ca-salts using a saturated FA containing material. Nutrient content and FA profiles of produced supplements were determined and ruminal biohydrogenation and oil release were examined in vitro. Additionally, in a complementary in vivo experiment, effects of dietary inclusion of fish oil, ca-salts and encapsulated ca-salts on nutrient digestibility and ruminal paramerters were evaluated using three rumen fistulated Holstein cows. Encapsulation of Ca-Salts increased protection efficiency of PUFA against ruminal biohydrogenation. Encapsulated ca-salts with 10 % of wall material (weight basis) had lower biohydrogenation afer 48-h in vitro incubation (P˂ 0.05). Encapsulation of ca-salts decreased rumen oil release but oil release in other simulated media or total tract oil release were not affected by encapsulation (P˃ 0.05). Protected supplements increased nutrient digestibility compared with fish oil (P˂ 0.05). Results of ruminal parameter analysis can warrant inertness of ca-salts and encapsulated ca-salts in the rumen of experimental animals. Fish oil decreased acetate and rumen N-NH3 concentration as well as protozoa `population, but increased propionic acid concentration (P˂ 0.05). Encapsulation of Ca-Salt did not changed rumen parameters (P˃ 0.05). According to the results, it can conclude that encapsulation of ca-salts increased protection of PUFA against ruminal biohydrogenation without worse effects on rumen parameters. Encapsulation with 10 % of wall material (weight basis) can be concluded as the best treatment according to chemical composition, fatty acid profiles, rumen biohydrogenation and oil release data.

This experiment was conducted to evaluate the effect of thyme essential oil and capsulated form on performance, carcass traits yields, feed intake, blood metabolite, in broiler chicks. This experiment was conducted in a completely randomized design with 4 treatments, 4 replicates and 12 broiler chicks per each replicate. The experimental treatments was consist 1) basal diet 2)basal diet 200 ppm thyme essence 3) basal diet 200 ppm encapsulated thyme essence 4) basal diet 100ppm encapsulated thyme essence. Body weight, feed intake and feed conversion were measured at the end of each experimental period. 10d Body weight at was significantly differ between control and other treatments significantly (P

Identification of selection targeted genomic regions is one of the main aims of biological research.The objective of this study was a genome-wide scan to identify the genomic regions that have been under artificial and natural selection in Zandi sheep breed. For this purpose, 96 animal of Zandi breed have been genotyped using the Illumina ovine SNP50 BeadChip. The intergrated hapl-type score (iHS) test was used to detect the selection sweep, due to linkage disequilibrium, associated with these signatures. The results revealed eleven genomic regions on 1 (two areas), 3, 6, 7,8, 9, 10, 17, 22 and 26 chromosomes. Bioinformatics analysis demonstrated that some of these genomic regions overlapped with reported genes that directly and indirectly influenced traits for adaptation to hot arid environments (DNAJB4, HSPA4L, MSRB3), immune response (IL23A, STAT6, LY96), body size and development (STAC3, LAP3), development of the skeletal system (SPP1, MEPE, IBSP) and energy and digestive metabolism (ATP5B, GLS2, CS). Finally, study of the reported QTL in these regions of the sheep genome showed that they overlapped with QTL of economically important traits such as carcass yield, growth and wool traits. However, it will be necessary to carry out more association and functional studies to demonstrate the implication of these genes.

This study was conducted to investigate the effects of supplementing fattening lamb diet with various levels of commercial supplement Fortide C, produced from enzymatic hydrolysis of cottonseed meal as a source of small chain peptides, on in vitro gas production and fermentation parameters, nutrients digestibility and activity of rumen microbial enzymes in vitro using rumen liquor of sheep. Dietary treatments were control diet (without Fortide C) and supplementing control diet with Fortide C at the levels of 2.35, 4.70 and 7.70 g/kg of diet on dry matter basis. Results showed that at 16, 24 and 48 h of incubation, the highest and the lowest volume of gas production (GP) was observed in the diet containing the highest level of Fortide C and control diet, respectively (P 0.05). Activity of carboxymethyl cellulase and alpha-amylase increased as the level of Fortide C increased in the diet compared to the control diet (P

The aim of present experiment was to investigate the buffering capacity of some buffers or alkalizers, their effect on digestion and fermentation of high concentration diets. The concentration of 0, 0.5, 1, 1.5, 2 g in 100 ml from different buffers and alkalizing agents including: sodium bicarbonate, sodium sesquicarbonate, magnesium oxide, magnesium carbonate, sodium bentonite, zeolite and combined buffer (0.75% sodium bicarbonate 0.75% sodium sesquicarbonate) was used. The initial pH of the buffer solution, the amount of consumed hydrochloric acid for abrupt changes of pH to 5.2 or below it, and the final pH was registered. The lowest amount of the hydrochloric acid was consumed for solutions containing sodium bentonite, magnesium oxide, magnesium carbonate and control for suddently dropping their pH; and highest amount by sodium sesquicarbonate, combined buffer and sodium bicarbonate, respectively. The zeolite buffer also indicated a proper resistance to pH changes and did not have a significant difference with the combined buffer or sodium bicarbonate buffer. The treatments in gas production were included: control or basal diet without buffer, and amounts of 0.5 to 2% sodium bicarbonate, 0.5 to 2% sodium sesquicarbonate, 0.5% sodium bentonite, 2% magnesium carbonate, 1.5, 2 and 2.5% of zeolite and combined buffer, which were added to basal diet. The highest produced gas was in the sodium sesquicarbonate, sodium bicarbonate, combined buffers and zeolite. Therefore, sodium sesquicarbonate, combined buffers, sodium bicarbonate and zeolite had the best position respectively, which were evaluated as suitable buffers for using in diets containing high concentration ingredients for feeding the ruminant animals.

In order to increase the accuracy of genomic best linear unbiased prediction method (GBLUP), bootstrap aggregating sampling (bagging) technique was applied. In this order a genome consisted of 10,000 bi-allelic single nucleotide polymorphism (SNP) over ten chromosomes, with 100 cM length each, was simulated. To generate linkage disequilibrium (LD) between SNPs and quantitative trait loci (QTL), random mating was simulated for 100 generations between 100 individuals (50 males and 50 females). Then in generation 101 (reference population) number of individuals increased to 1000 or 2000 and their phenotypes were also simulated. Then the marker effects were estimated in this population using GBLUP method or combined this method with bagging technique (BGBLUP). By using these regression coefficients and according to the genotype markers for juvenile individuals in generations 102 to 105, called validation population which had no phenotype, genomic breeding values were predicted. According to the finding of this research, the accuracies of genomic breeding values of GBLUP method were higher than those for BGBLUP (p > 0.05) and about the first testing set (102 generation) and regardless of QTL effects with a population of 1000 (or 2000) observations in the reference set, the range of GBLUP accuracy was 0.339±0.049 (0.412±0.042) for a trait with 0.05 heritability to 0.728±0.015 (0.783±0.015) for a trait with 0.65 heritability, whereas the accuracy of BGBLUP method were varied between 0.338±0.047 (0.411±0.042) to 0.725±0.016 (0.780±0.015).

Social interaction among individuals can have important influences on the production and fitness traits in livestock population. Therefore, the aim of this study was to estimate variance components due to social effects for two production traits including egg weight and body weight in a commercial broiler chicken line. In this study 29,645 production records provided by Arian commercial broiler chicken line center of Iran from 2007 to 2016 were used. Data were analyzed with four different single-trait animal models including or excluding random genetic social and pen effects, using AI-REML algorithm. For each trait, the most appropriate model was chosen based on Akaike information criteria. Based on the most appropriate fitted models, direct heritability estimates ranged from 0.60±0.02 (egg weight) to 0.55±0.02 (body weight). Even though social genetic variance was small, it was significantly different from zero for body weight and egg weight. The variance due to random pen effect was significant for egg production traits. In general, social genetic and pen effects were important effects regardless of trait under study. Correlation between direct and social genetic effects was negative (-0.51) for egg weight and positive (0.27) for body weight. Overall, we concluded that social genetic and pen effects should be included in the statistical models for genetic evaluation of egg weight and body weight in broiler chicken.