نشریه علوم دامی (پژوهش و سازندگی)
پیاپی 103 (تابستان 1393)

This research was conducted to study the nutrient balance condition of dairy cattle in semi industrial dairy farms of sought west of Tehran province (Eslamshahr) by the questionnaire techniques. The farms based on the herd were categorized in 6 group as follows: 1(1-30), 2(31-60).3(61-100), 4(100-130), 5(130-200) and 200 heads upward. The 30 farms have been selected randomly based on the randomized category sampling methods. In this survey more than 130 dairy farms (at least) including 1500 dairy cow's were investigated. The given ration has been compared with NRC tables and the differences were reported.The results showed that differences on dry matter intake, crude protein and net energy lactation per cow per day in 6 groups were 42.5, 18.1, 6.6, 21.8, 10.4, 17.4 and 36.5,-4.8,-23.5,-4.9,-16.4, 3.8 and 8.4,-0.7,-7.1, 3.02,-3.02 and 1.5% consequently. The differences for minerals of Ca and P were42.4,19.8,22.5,8.4,29.9,13.4 and 53.1, 39.1, 38.7, 43.6, 37.4 and 39.2 respectively. The amounts of NDF and ADF in all categories were higher than recommended levels. The daily received amounts of K, Mn, Cu, Zn. Fe, Mg, ADF and NDF were higher than recommended levels too. Mineral imbalance in ration have very important role in farm income and dairy cattle health. For this reason education and increasing information of farmer about this matter, are very important.

The aim of this study was to estimate genetic parameters of age at first calving and its relationship with productive traits of Holstein dairy cows. A total of 24491 first lactation records (2X 305d) which were collected from 1995 to 2009 were used. The general linear model (GLM) procedure was applied to determine effective factors on studied traits. Herd-Year-Season (HYS) and age at first calving (AFC) were fitted as fixed and covariate factors in the model respectively. Variance components and corresponding genetic parameters were estimated based on bivariate animal models by restricted maximum likelihood (REML) method. HYS and AFC affected significantly studied traits including milk production, fat production, protein production, fat percentage and protein percentage. Mean and heritability of age at first calving were obtained 25.08±1.8 and 0.093±0.01 respectively. Twenty nine percent of heifers calved at 24.5 (24-25) months. The genetic and phenotypic trends of AFC were -0.015 and -0.09 respectively (P<0.001). Phenotypic and genetic correlations of AFC with milk yield, fat yield and protein yield were negative. Conversely, positive genetic and phenotypic correlation observed between AFC and fat-protein percentage. The results showed that reducing age at first calving can increase milk-fat-protein production and the optimum AFC for milk-fat-protein production was 22.5 (22-23) month in this study. Also, reducing age at first calving to 22 month has a negative effect on milk, fat and protein production.

In order to evaluation of genotype by environment interactions in Holstein cows, Iran was divided into cold, middle cold, temperate and hot climate regions. For this purpose used from 39570, 35813 and 18955 records for milk, fat and protein yields, respectively, to progeny test for 35 sires that have 50 daughters in each climate. The data were collected by the Centre of Breeding and Improvement of Livestock Production from 775 herds, during 1991 to 2009 years. Breeding values for milk, fat and protein yield for each animal were predicted from multiple traits with animal model (BLUP). Average of breeding value estimated for sires in cold, middle cold, temperate and hot climate was 75.53, 377.74, 167.08 and 81.49 kg for milk yield, -0.18, 5.42, 1.85 and 1.63 kg for fat yield and 0.96, 8.05, 3.93 and 1.94 for protein yield respectively. Spearman correlation for milk yield for cold-middle cold, cold-temperate, cold-hot, middle cold-temperate, middle cold-hot and temperate-hot also was 0.63, 0.61, 0.45, 0.87, 0.54 and 0.48 respectively, for fat yield was 0.63, 0.69, 0.52, 0.91, 0.49 and 0.40 respectively, and for protein yield was 0.61, 0.62, 0.39, 0.81, 0.48 and 0.41, therefore spearman correlation estimated show that ranking of sires was difference at different climates and existent genotype by environment interaction at difference regions of Iran.

In order to estimate the genetic parameters and comparison legendre polynomials for production traits of Iranian Holstein dairy cattle test-day records of first lactation cows for milk yield, fat yield, protein yield, fat percentage and protein percentage traits were used. These records collected from 2006 to 2010, by the Animal Breeding center of Iran. The genetic parameters were estimated using REML algorithm by random regression model with legendre polynomials of order 3 to 5. According to the results, order 5 of legendre polynomials were proposed for fitting permanent environment and additive genetic effects for the milk yield, fat and protein percentages traits, and order 4 of legendre polynomials for the fat and protein yields. Residual variances were considered homogeneous over the lactation period. The Phenotypic variance of the considered traits during lactation was not constant and it was higher at the beginning and the end of lactation. Additionally, the estimated permanent environment variance was larger than genetic variances throughout the lactation. Estimates of heritability were found to be lowest during early lactation. The additive genetic correlation between lactation adjacent days were more than between distant test days. The genetic trend of milk yield was showed an increasing phase during the10 past years, while this genetic trend for fat and protein percentages declined.

The aims of the present study was to evaluate the level of aflatoxin B1 (AFB1) in feedstuffs (corn silage, corn, dried alfalfa, cottonseed meal, cottonseed, soybean meal, canola meal, barley, wheat bran, concentrate, sugar beet pulp and wheat straw) that collected from dairy herds in Khorasan Razavi Province that classified according to milk yield in very high (>10000 Kg/day), high (5000-10000 Kg/day), intermediate (2000-5000 Kg/day) and low (<2000 Kg/day) milk production. Sampling was performed during cold (early December to late January) and warm (early June to late July) seasons. Feed samples were placed in sterile packages and were maintained until test at -18 °C. Aflatoxin B1 levels were measured using ELISA. Results showed significant differences between the amount of aflatoxin B1 in cottonseed meal, canola meal, wheat bran, sugar beet pulp and wheat straw among all dairy herd classes (P<0.05). The contents of aflatoxin B1 in all feedstuffs during the cold seasons were higher than those of warm seasons. Results also showed that aflatoxin B1 level in %21.87 of the total diet samples were higher than the maximum tolerance limit (50 ng/g).

Tumor necrosis factor -alpha (TNFα) is a proinflammatory cytokine that plays critical roles in the regulation of immune responses including macrophages activity and apoptosis. TNFα gene is polymorphic and its haplotypes have been associated with resistance or susceptibility to disease. This study was undertaken to identify the polymorphism of TNFα gene in Makoei sheep, using polymerase chain reaction (PCR) and single strand conformation polymorphism (SSCP) technique. A total number of 90 Makoei sheep were randomly selected from Makoei Sheep Breeding Station where located in Mako and blood samples were collected. Genomic DNA was extracted from blood samples in order to amplify 273 bp fragment comprising part of the fourth exon and the 3ʹ untranslated region (3ʹ UTR) of the ovine TNFα gene. PCR products were subjected to SSCP analysis. Based on the obtained SSCP patterns three alleles E, O and R with frequencies of 73.33, 17.78 and 8.89 % and three genotypes EE, OE and RE with frequencies of 46.67, 35.56 and 17.77 % were identified, respectively.

Assessing genetic biodiversity and population structure of minor populations through the information provided by neutral molecular markers, allows determination of their extinction risk and to design strategies for their management and conservation. Analysis of microsatellite loci is known to be highly informative in the reconstruction of the historical processes underlying the evolution and differentiation of animal populations. Iranian goat populations are recognized as an invaluable component of the world’s goat genetic resources. The aim of this work is to study the genetic status of Raeini goat population through the analysis of molecular data from 13 microsatellites markers. The mean expected heterozygosity across loci within populations ranged from 0.716 to 0.852. Genetic diversity measures revealed a good status of biodiversity in the Raeini goat population. The observed number of alleles ranged from 4 (ILSTS022) to 10 (BM121) with a total of 92 alleles and mean of 7.08 alleles across loci. The overall heterozygosity, PIC and Shannon index values were 0.808, 0.76 and 1.719 indicating high genetic diversity. Only 5 out of 13 loci were in Hardy-Weinberg equilibrium. The mean Fis was -0.016. Only 4 loci had positive Fis values and 9 loci had negative values. Genetic bottleneck hypotheses were also explored. Our data suggest that the Raeini goats have not experienced a genetic bottleneck in the recent past.

This study was conducted to evaluate effects of rosemary essential oils (REO) on feed digestibility, blood and rumen parameters of Ghezel sheep. Four male sheep with average body weight 46±2 kg were used in a 4×4 Latin square design. Treatments composed of Basal diet (control) in addition to diets containing 100 (RO100), 200 (RO200) and 400 (RO400) mg/day of REO. Sheep's fed with 4 diets at 4 periods of 21 days (14 days as adaptation and 7 days for sample collection). Digestibility was determined by fecal collection method. On 20 day of the experimental period, Ruminal liquor samples were taken at 0, 2, 4 and 6 hours after feeding for rumen pH, N-NH3 and total volatile fatty acids measurements. On the last day of each measurement period, Blood samples were taken at 0 and 4 hours after feeding, via jugular vein, and analyzed for glucose, urea, and total protein and creatinine contents. The results showed that Ruminal total volatile fatty acids in RO100 diet were lower than control and RO200 diets (P˂0.05). Ruminal ammonia concentration in control diet was higher than RO100 diet at all sampling times and also RO200 diet was higher than RO100 and RO400 diets (P<0.05). Blood creatinine concentration in control diet was higher than RO400 diet at 4 h after feeding (P<0.05). In conclusion, treatment of 200 mg/day REO may have positive effect on feed digestibility and rumen fermentation of sheep; however more experiments are required in this field

This experiment was conducted with broiler chickens to evaluate the effects of High and Low Swelling Bentonite (Natural and Processed by CuSo4) supplementation in diets on performance and carcass traits. A total of 300 day-old Aryan broiler’s chicks were used in a completely randomized design with 5 dietary treatments. Six pen replicates of 10 chicks were assigned to each of five dietary treatments, which included: 1) corn-soybean meal basal diet(control); 2) basal diet supplemented with % 1 high swelling bentonite(HSB); 3) basal diet supplemented with % 1 processed high swelling bentonite (PHSB); 4) basal diet supplemented with % 1 low swelling bentonite(LSB); and 5) basal diet supplemented with % 1 processed low swelling bentonite(PLSB). Body weight and feed intake were recorded weekly over 42 d. Results showed that HSB supplemented diets significantly decreased body weight and feed intake, and increased feed: gain ratio in comparison to other treatments. Also, the production index in birds fed HSB diet, were lower than birds fed on diets containing PHSB(P < 0.05). PHSB addition to diets significantly decreased (P < 0.05) the relative weights of gut and liver when compared to control P < 0.05). These results indicated that processed HSB by CuSo4 have better effects on growth performance, mortality reduction and improvement of production index broilers compared to HSB. It seems that using processed high swelling bentonite in diets contaminated by mold’s toxins to be better than low swelling bentonits

A study was conducted to evaluate the effects of blood pressure medications on index of liver damage in Ascites Incidence in broilers. A completely randomized experimental design with a 2×3 factorial arrangement (sex and feed additive), with 3 replicates of 12 birds, with 216 (108 male and 108 female) one-day-old (Ross 308) was applied. Feed additive includes control (without feed additive) levothyroxine and atenolol at level of 45 ppm in the basal diet after 21 days of age. Albumin and total protein of serum and ascetic fluid, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) enzymes acivity of serum were determined in 42 and 49 days of age. In 42 days of age 2 birds from each replicate and in 49 days of age all birds slaughtered and relative weight of spleen, liver and heart measured (ratio body weight). Total ascites mortality and ascites morbidity (the ratio of right ventricular weight to total ventricular weight) in 42 and 48 days of age. Levothyroxine in diet increased the ALT an AST activity in contrast reduced albumin and total protein of serum. Relative weight of spleen decreased in response to levothyroxine in diet but relative weight of heart and liver increased. Ascites mortality and ascites morbidity decreased in response to atenolol in diet. The results of this experiment indicated Levothyroxine could be a replacement of cool temperature in rearing period for ascites incidence in broilers.

In this study, Effect early age feed restriction and thermal conditioning on growth, carcass characteristics broiler chickens subjected to heat stress Was evaluated. Three hundred chicks (cobb500) were randomly divided into four equal groups as treatments including thermal conditioning group (TC), feed restriction-thermal conditioning group (TCFR), feed restriction group (FR) and control group (C), each group was replicated 5 with 15 birds per replicate.The groups TC and TCFR were exposed to thermal conditioning (38±1 C, for 24 h) at third day and the FR and TCFR groups were exposed to feed restriction for seven hours (10 am to 5 pm) at 7-14 days. Mid (26 days) and late period (40 days) culture, blood samples were taken to measure serum biochemical parameters. Thermal conditioning increased BW at 42d of age (P < 0.05). Feed Restriction decreased BW and feed intake at 21d of age(P < 0.05). In thermal conditioning birds at 26 d of age, Triglyceride (P < 0.05). In feed-restricted birds at 26 d of age, Cholesterol (P < 0.05) were increasedin serum. Also at 40 days of age, Thermal adaptation of phosphorus was significantly increased (P < 0.05). thermal conditioning, Feed Restriction and their effects on serum blood glucose and total protein levels were not significant (P < 0.05). The results indicated that early age thermal conditioning improves broilers performance under summer heat stress condition.

This experiment was performed to determine the role of vitamin E and coenzyme Q10 antioxidants on performance and ascites parameters of broiler chicks in cold stress conditions using a completely randomized design with 5 treatments and 5 replicates in each treatment. Treatments were: positive control (PC, normal thermal conditions without antioxidants), negative control (NC, cold stress without antioxidants), NC + vitamin E (150 mg/kg diet), NC + Q10 (40 mg/kg diet) and NC + E (150 mg/kg diet) + Q10 (40 mg/kg diet). Temperature decreased gradually between days 15 to 21 and fixed at 15oC afterwards. Result showed that there were significant differences between treatments in body weight gain (BWG) and feed conversion ratio (FCR) (p<0.05). The NC group had the lowest BWG and the highest FCR amongst the dietary treatments but there were no significant difference between positive control and antioxidant group for this trait. In spite of a higher amount of FI for the negative control, there were no significant differences in FI between the treatments. Ascites indicators such as heart weight, RV/TV ratio, red blood cell count, hematocrit, and T3/T4 ratio were significantly increased in the negative control (p<0.05). Antioxidants in stressful conditions improved these parameters. Beside of an increase in liver weight and T3 were observed in the negative control but the differences were not significant (p<0.05). In general, the use of vitamin E and coenzyme Q10 antioxidants led to improvement in performance and ascites index in broiler chicken exposed to cold stress.

This experiment was conducted to evaluate the effects of different levels of crude protein and probiotic in diets on performance, egg quality and blood biochemical and immunity parameters of laying hens. A completely randomized design with factorial method (2×4) was conducted in which two levels of crude protein (NRC and 10% lower than NRC recommendation) and 4 levels of probiotic (0,. 025%, 0.05% and 0.075%) were tested on 288 of Hy- line (W36) laying hens for 12 weeks from 42-54 weeks of hens ages. Results showed that the different levels of crude protein and probiotic in the diets have significant effects on performance, egg traits and immunity parameters of laying hens (P<0.05). Low crude protein diet significantly reduced the egg production percentage, egg mass, feed intake and increased the feed conversion ratio. Inclusion of probiotic in the diets decreased the amount of daily feed intake. Using different levels of probiotic with different levels of crude protein could not improve the performance of laying hens. The shell surface weight was decreased when the laying hens received low protein diet. Inclusion of probiotic improved the egg specific gravity, but the highest level of probiotic decreased the eggshell percentage. The blood hemoglobin percentage was positively affected by the probiotic content in the diet. Different levels of dietary crude protein, probiotic and interaction between them could not significantly changed the blood biochemical parameters

This experiment was conducted to investigate the effect of different levels of Saccharomyces cerevisiae cell wall on performance, carcass traits and intestinal morphology in broilers. In this experiment 240 Ross- 308 broilers were used in 4 treatments, 5 replicates and 12 bird in each replicate in a completely randomized design for 42 days. The treatments included: 1) control group (without Saccharomyces cerevisiae cell wall, (in treatments 2, 3 and 4 the amounts of Saccharomyces cerevisiae cell wall were 0. 5, 1 and 1.5g/kg. Weight gain, feed intake and feed conversion ratio were measured periodically. In 28 and 42 days of experiment period, 2 bird from each replicate for measure of carcass traits and intestine morphology randomly selected and slaughtered. The experimental treatments significantly affected the performance, carcass traits, and intestinal morphology of broilers in 28 and 42 days of experiment period (p<0.05). The best results were obtained by using 1.5 g/kg of Saccharomyces cerevisiae cell wall in diet. Different levels of Saccharomyces cerevisiae cell wall did not have any significant effects on size of liver, spleen and bursa of Fabricuse (p>0.05). The overall results showed that in broilers using 1.5 g/kg of Saccharomyces cerevisiae cell wall in diet improve their performance, carcass traits and intestinal morphology.

This study was carried out to evaluate the effect of different levels of essential oils of wormwood (Artemisia absinthium) and cumin (Cuminum cyminum (on antioxidant status, lipid peroxidation and serum metabolites in broiler chickens for 42 days. 336 day-old male broiler chicks (Ross 308) were allocated to 7 treatments with 4 replications. Dietary treatments were included a corn-soybean based diet as control, and groups of containing 100, 200 and 300 part per million (ppm) of wormwood and cumin essential oils. At the end of experiment, two birds per each replicate were randomly selected, bled and then killed to determine antioxidant indexes and serum metabolites. Chemical analysis of worwood and cumin essential oils by gas chromatography–mass spectra (GC-MS) showed as the main constituents β-pinene (24.2%) and γ-terpinene (26.24%), respectively. Results showed that addition of 200 and 300 ppm of wormwood essential oil and 300 ppm of cumin essential oil significantly increased (P<0.05) glutathione peroxidase activity in liver and kidney when compared with the control group. Also, treatment of 200 ppm cumin essential oil significantly increased (P<0.05) glutathione peroxidase activity in kidney than control group. Chicks received 200 and 300 ppm cumin essential oil and 200 ppm wormwood essential oil in the diet, had higher (P<0.05) superoxide dismutase activity in liver than control group. There were no significant difference between experimental groups regarding liver and kidney catalase activity and liver superoxide dismutase activity (P>0.05). Adding 300 ppm wormwood and cumin essential oils significantly increased (P<0.05) total antioxidant capacity in serum compared with the control group. Supplementation of diet with wormwood and cumin essential oils, significantly decreased (P<0.05) malondialdehyde concentration in liver, kidney and serum, and significantly decreased serum cholesterol and LDL concentration. Serum HDL concentration significantly increased (P<0.05) than control group, but did not significant affect on other serum metabolites.In general, results indicated that addition of wormwood and cumin essential oils to diet, caused improvement body antioxidant system, increased serum HDL, and decreased serum cholesterol and LDL concentration in broiler chicks.

The experiment was designed to study the changes in production performance and egg quality of old laying hens after injection of different doses of growth hormone (GH) and testosterone (Ts). A total of 160 old laying hens (HyLine W-36) at 73 wks of age were randomly assigned to four treatments with four replicates and 10 birds in each replicate in a completely randomized design. Treatment groups were: treatment 1: injection of 100 µl distilled water (control group), treatment 2: injection of 500 µg Ts/kg live-weight+50 µg GH/kg live-weight, treatment 3: injection of 500 µg Ts/kg live-weight+100 µg GH/kg live-weight and treatment 4: injection of 500 µg Ts/kg live-weight+150 µg GH/kg live-weight. During second and third weeks after the hormone injection production performance and egg quality parameters were measured. Ovulation rate (egg production percent), egg mass and feed intake of treatment three significantly increased compared to control group (p<0.05). Feed conversion ratio (FCR) was significantly higher in treatment four compared to other treatments (p<0.05). Treatment 3 caused higher egg weight, albumen height, eggshell weight, eggshell density and eggshell weight per surface area (ESWSA) compared to control group (p<0.05). Yolk height in treatment 2 was significantly lower than other treatments (p<0.05). Shell breaking strength of control group was significantly higher than all injected groups. In conclusion, our results showed the positive effects of GH and Ts administration on old laying hens’ performance and egg quality parameters.

Two hundred and twenty one-day male chicks (Ross 308) were used in a completely randomized design with 5 treatments and four replicates each to investigate the effects of the different levels of 0.15, 0.3 and 0.6 percent rosemary extract along with nitrate (27.4 mg sodium nitrate/liter water) in drinking water on growth, some blood parameters and carcass characteristics of broiler chickens. No different difference was observed between the treatments for feed consumption and body weight gain (P˃0.05). Nitrate consumption increased the feed conversion ratio which was removed by rosemary extract (P<0.05). Rosemary extract had no effect on alanine aminotransferase (ALT) but nitrate increased the aspartate aminotransferase (AST) activity (P<0.05). Consumption of 0.3 and 0.6 percent rosemary extract deducted the blood HDL of nitrate consumed birds (P<0.05). Liver weight was decreased by the highest rosemary level (P<0.05). Totally rosemary extract consumption lowers the liver and lung damages through its antioxidant effects in broiler chickens under nitrate treatment. Hence it diminishes the liver and lung weights and aspartate aminotransferase activity and as a consequence improves the feed conversion ratio.

To determine the amount of food amino acid and to spend time in the laboratories are expensive & time-consuming due to a chemical analysis. In the current laboratories, digestion NIRS method is widely used for this purpose. But this method has technical limitation. Therefor is important find appropriate method for estimate amount of amino acids. Artificial Neural Network (ANN) can provide a better reflection of the relationship between approximation feed composition and particular nutrient amount in that feed. Therefore, this study was performed to estimate amino acids corn and wheat by using artificial neural networks and multiple linear regression (MLR). In neural models used in the study, input variables include crude protein, crude fat, crude fibre, phosphorus and ash, and output variables includ profiles of amino acids relevant to combination of these two types of feed. The Results showed that there is a significant relationship Between amino acids in corn and wheat and its chemical composition. Also The statistical evaluation showed that the ANN model compared with MLR was a stronger estimation for prediction the amount of each amino acids. Hence the artificial neural network as a powerful tool for modelling, forecasting and estimating the nutrient composition of foods used poultry. Using the results of this study, it is recommended that artificial neural network can be used as a computational method with sufficient accuracy for modelling, prediction and estimation of the nutrient composition of foods used in poultry.

Since the last decades, hydroponic fodder production systems have been experienced in some parts of the world. During the germination process, the growth of embryo results in the rupture of the seed coat and emergence of a young plant which it reaches to about 20cm height in a week. Apparently, the concept of putting one kilogram of seeds into a hydroponic system to obtaine several kilograms of fresh green fooder, during 7-10 days period, is appealing. Although it seems like growing a lot of feed, but in fact, increase in fresh weight is due to water and most often there is a reduction in dry matter weight and energy obtained compared with the initial grain. This technique is less a case of growing feed and more a case of spending grain and additional cost to change its quality and reduce its dry matter weight. During soaking and germination, seeds lose dry matter as they use their own endosperm energy reserves for growth, results in a carpet math of roots, green and seed residues that contains high amount of water and low dry matter. There are a number of challenges in producing hydroponic fodder and its nutritive value, but research reports indicated that the balance of DM yiled and recovery of energy is negative when grains converted to green fodder in this system. Using of hydroponic fresh forage in the diets of different animals has not shown advantages over the initial grain hence it increases the feeding cost. Contamination of green grass by mulds and mycotoxines is the other risk of the system that will affect the animal health and products. This paper evaluates and discusses the mentioned aspects of forage production in hydroponic system.