جستجوی مقالات مرتبط با کلیدواژه "افزایش وزن روزانه" در نشریات گروه "علوم دام"

Several studies have been conducted regarding the importance of the availability of various minerals and vitamins for the growth and performance of livestock. Selenium and vitamin E are among the substances that have attracted the attention of researchers. Different dosses, appropriate time of consumption, and method of use are the aria that have been researched. Although the reports presented are not aligned and, in some cases, contradictions are observed. Therefore, in this study, the effect of oral and injectable supplementation of selenium and vitamin E on growth performance and some blood parameters of growing lambs was investigated.

Eighteen three-month-old lambs with an average weight of 18.6 ± 2.7 were kept randomly in three groups with six repetitions in individual cages for eight weeks. Experimental treatments included: control group (base diet without supplements), oral group (base diet plus 0.3 mg of selenium in the form of selenomethionine and 50 mg/kg of vitamin E in the form of alpha-tocopherol), injectable group (4 ml injectable supplement; each ml contains 0.5 mg of selenium in the form of sodium selenite and 50 mg of vitamin E in the form of alpha-tocopherol). The lambs were weighed every 15 days and, on the 1st, 30th, and 60th days of the experiment, blood was drawn from the Juglar vein

There was no statistically significant difference between experimental groups in terms of daily feed consumption, final weight gain and feed conversion ratio. Blood concentrations of zinc, copper and iron were not affected by supplementation. Cholesterol, triglyceride, high, low and very low-density lipoprotein concentrations were not affected by the method of supplementation. The number of red blood cells was not affected, but the number of white blood cells in the injection group increased significantly compared to the control group on the 60th day of the experiment (P<0.05). In terms of the activities of alanine aminotransferase, aspartate aminotransferase and superoxide dismutase, no significant difference was observed between the experimental groups, but the activity of glutathione peroxidase on the 30th and 60th days of the experiment and the total antioxidant capacity on the 60h of the experiment in the group receiving oral supplements were more than other experimental groups (P<0.05). Malondialdehyde index decreased in the groups receiving selenium and vitamin E supplements compared to the control group (P<0.05).

The results of this experiment showed that the use of oral supplements of selenium and vitamin E improved the antioxidant capacity of lambs by both oral and injectable methods, and no significant difference was observed between the two methods. However, due to the convenience of the oral method and the reduction of stress caused by the injection and its non-invasive nature, it is recommended to prescribe an oral supplement. ‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬ ‬‬‬‬‬‬‬‬‬‬

The use of medicinal plants as growth promoters is known as one of the suitable alternatives with multiple effects instead of antibiotics in animal feed. Several studies have been conducted on the use of medicinal plants or their essential oils and extracts in ruminants, but in most of these studies, the effect of these plants has been directly investigated on the growth and production performance of the animal itself. In this experiment, the effect of a mixture of medicinal plants as nutritional additives in the diet of Raman lactating ewes on the performance and blood parameters of male suckling lambs has been investigated.

Twenty-four lactating Roman ewes of the first calving, the average BW of 50.2 ± 1.2 and the average milk yield of 1107.03 ± 122.25 along with 24 suckling male lambs with an average BW of 3.34 ± 0.44 were divided into four groups six in each, in a completely randomized design and kept in individual pen for 65 days. The experimental groups of mother ewes included: control (basic diet) and first, second and third treatments, in addition to the basic diet, were received 15 grams of cumin, coriander and peppermint mixed powder with the ratios of 60:30: 10; 10:45:45 and 30:60:10 %, respectively. Male lambs did not receive the herbal mixture supplement. Lambs were weighed every 15 days. At the end of the experiment, before morning feeding, blood was taken from the jugular vein of the lambs in order to determine the parameters of hematology, biochemical, liver enzymes and antioxidant properties.

Based on the results of this research, no significant difference was observed between the control group and treatments in terms of final weight and daily weight gain of lambs. The concentration and volume percentage of red blood cells of lambs in the third treatment were lower than in other groups (P<0.05). The amount of hemoglobin was higher in the first treatment and lower in the third treatment, but there was no significant difference with the control group. The number of white blood cells and the differential count of these cells were not affected by the experimental treatments. The blood glucose concentration was the highest in the first experimental treatment and the lowest in the third treatment, although there was no significant difference compared to the control. The concentration of this parameter in the first compared to the third treatment was statistically different (P<0.05). There was no significant difference between the experimental groups in terms of total protein and creatinine concentrations. Triglyceride concentration in the second treatment was higher than the control (P<0.05). Aspartate aminotransferase activity in the second and third treatments was lower than in the control (P<0.05). Superoxide dismutase activity, total antioxidant capacity and malondialdehyde index were not affected.

The results of the experiment showed that the use of a mixture of cumin, coriander and peppermint plants with different proportions in the ration of mother ewes, despite the favorable effects on some blood parameters of suckling male lambs, did not have a significant effect on the performance and antioxidant status of their blood.

Introduction: 

In order to maximize poultry production, it is important to have knowledge of the bird's requirements. This can help to increase their production capacity. Since feed is a major expense in poultry production, it is crucial to consider the main components of the feed. Energy and protein are vital nutrients for poultry. Energy is necessary for body function, while protein is an essential constituent of all tissues in the bird's body. Proteins have a significant impact on the growth performance of birds, and they are also the most expensive nutrient in broiler diets. A lot of research has been done to better utilize feed by the animal and reduce feeding costs. This is important because diets that contain excessive amounts of certain nutrients can lead to nutrient loss and increased breeding costs. The Khazak hen is a native hen of the Sistan region and is known for its small body size. Achieving better growth performance in this bird requires determining the optimal levels of energy and dietary protein in different phases of production. Since there is no information about the optimal level of energy and protein in the growth period for Khazak chickens, so this study was conducted to determine the effect of different levels of energy and protein on growth performance of Khazak native chickens and select the best combination of energy and protein levels at 7 to 91 days of age.

The research was performed on Khazak chickens in the Research Center of Domestic Animals (RCDA) in the University of Zabol, Zabol, Iran. A total of 360 seven- day- old chicks were randomly allocated to 9 dietary treatments including three levels of energy (2600, 2800 and 3000 kcal / kg) and protein (17, 19 and 21%) as a factorial experiment in a completely randomized design with four replications, and 10 birds in each replication. The chicks entered the experimental pen in seven days of old and they were examined with experimental diets for 12 weeks. The birds had ad libitum access to feed and water throughout the experiment. Eenvironmental conditions in terms of light, temperature and humidity were considered similar for experimental treatments. Weighing chickens and feed intake were measured weekly. Other parameters including average daily body weight gain, feed conversion ratio, daily energy and protein intake, energy and protein efficiency ratio were calculated based on the body weight and feed intake data, in three age ranges (7 to 35, 35 to 63 and 63 to 91 days of age) and the whole period. The collected data were analyzed using GLM procedure of SAS software version 9.1 and the means were compared with Tukey test at 5% level.

The study results indicate that varying energy and protein levels had a significant impact on weight gain, feed intake (except during the 63-91 day age range), feed conversion ratio, and energy and protein intake (excluding the 63-91 day age range) during all three periods studied as well as over the entire period (P < 0.05). Furthermore, the interaction between energy and protein showed a significant effect on all variables studied across all periods (P < 0.05). However, the impact of energy and protein levels on protein efficiency ratio (PER) and energy efficiency ratio (EER) was not significant. During the starter period, physical limitations may cause birds to consume less energy with low-density diets. Thus, when birds consume diets that are low in energy and protein during this period, their energy consumption declines due to these physical limitations. The study results indicate that determining optimal energy and protein levels in the diet is crucial for maximizing the performance of native chickens. To balance poultry performance and economic production, an applied feeding program that compromises between the animal's nutritional requirements and management needs is necessary. Consequently, one approach to achieving this balance is by developing a diet formulation that can regulate a specific ratio of protein to renewable energy.

Although, the many performance variables were not significant between energy levels of 3000 with 2800 kcal/kg and protein levels of 21 with 19%, but the negative effect on performance was observed by reducing energy level to 2600 kcal/kg and protein level to 17 %. So level of 2800 kcal/kg and 19% for energy and protein suggested for these ages of chickens.

This research was conducted to study the effect of chickpea straw and strawberry forage in the diet of fattening calves. Eighteen Simmental male calves with initial weight of 285.16±38.15 kg were used in a completely randomized design with three diets over a four-month fattening period. Three diets were adjusted based on 70% concentrate and 30% forage. The forage section in the control was 18% alfalfa and 12% wheat straw, the second treatment was 25% strawberry plant, 3% alfalfa and 2% wheat straw and the third treatment was 25% chickpea straw and 5% alfalfa. The digestibility of diets was determined by acid-insoluble ash method. The use of strawberry forage and chickpea straw had no effect on feed intake and performance of calves. The digestibility of dry matter and organic matter in diet containing chickpea straw was higher than other complete feed blocks, however, the digestibility of NDF and ADF was higher in diets containing chickpea straw and strawberry forage than control . The feed conversion ratio in the group receiving chickpea straw was better than the control group. The cost price per kilogram of complete feed containing strawberry forage and chickpea straw were 20.2 and 24.57% lower than the control, respectively, which resulted in a reduction in feed cost per kilogram of increased calf weight compared to the control group. The results of this experiment showed that the use of strawberry forage and chickpea straw as a forage portion up to 25% in the diet reduced the cost of calf fattening.

This study aimed to compare the effects of combined buffer and sodium bicarbonate on growth performance and ruminal parameters of Holstein young bulls with an average weight of 330.8±43.1 kg and an age of 240 days, fed with a high-concentrate diet. The experiment was conducted for 90 days with 10 days of habituation in a completely randomized design with three dietary treatments and 10 replications, and a forage: concentrate ratio of 20 to 80%. Experimental diets included a control diet (without buffer), a basal diet with 1% sodium bicarbonate, and a basal diet with 1% mixed buffer. Daily feed intake, monthly weight gain, and digestibility were measured. The experimental diets did not affect feed intake, weight changes, and digestibility. The best feed conversion ratio for bulls was in treatment of diet containing the mixed buffer supplement (P<0.05). Daily weight gain was higher in bulls fed with the combined buffer than that of the control group (P<0.05). Rumen ammonia nitrogen was higher in the control group than the bulls receiving mixed buffer (P<0.05). The pH of rumen fluid was lowest in the control group, two hours after feeding (P<0.05). The present study results showed that the mixed buffer had a better performance in controlling the rumen acidity of bulls fed with high concentrate diets compared to sodium bicarbonate, especially in terms of improving feed conversion ratio, and it seems to be necessary to add it to such diets.

In this research, the effect of increasing the amount of alfalfa hay in the starter diet on the performance, blood parameters and health of Holstein dairy calves fed according to the milk feeding pattern by step down method using 24 female Holstein calves with 4±1 day of age and birth weight of 41.2 ±3 kg were studied in a completely randomized design with three treatments and eight calves in each treatment for 56-days (until weaning). Experimental treatments include: 1) feeding milk without alfalfa hay, 2) feeding milk with five percent of alfalfa hay (based on dry matter of the diet) and 3) feeding milk with 10 percent of alfalfa hay (based on dry matter of the diet). there was no difference between experimental treatments in terms of dry matter intake, feed conversion ratio, daily weight gain, fecal score, skeletal growth indices and ruminal pH. The concentration of propionate in the rumen of calves fed with milk and five percent alfalfa hay was significantly higher than the control and 10 percent forage treatments (P <0.05). The ratio of acetate to propionate in the rumen of calves fed milk and five percent alfalfa forage was significantly higher than of calves of other treatments. Plasma beta-hydroxybutyrate concentration was higher in calves fed the starter containing five percent of dry alfalfa than calves in other treatments (P <0.05). According to the results of this study, replacing part of the starter of dairy calves fed with high amounts of milk and alfalfa hay improves their rumen development.

The aim of this research was to investigate the effect of adding fat powder and flaxseed oil in milk on performance, growth, health, blood and rumen parameters of 45 suckling calves (avarage body weight = 38 ± 0.5 kg) in a compeletly randomized design in 10℃ of average temperature from d 3 to 30 of age in individual boxes. Experimental treatments included: 1- basal starter and milk without fat supplement (control) 2- basal starter and milk with fat powder (10 g/liter of milk) 3- basal starter and milk with flaxseed oil (10 g/liter of milk). Daily weight gain from d 3 to 30 and weight at d 30 were higher in flaxseed oil treatment than control treatment (P ≤ 0.05). Calves fed flaxseed oil treatment had higher hip height than control treatment at d 30 (P ≤ 0.05). Blood cholesterol concentration was higher in control treatmentthan flaxseed oil treatment and blood cortisol concentration was lower in flaxseed oil treatment than control treatment (P ≤ 0.05). The ratio oftotal protein to albumin in flaxseed oil treatment was lower than control treatment (P ≤ 0.05). Ruminal parameters were not affected by the experimental treatments. The results of this research indicated that using of fat sources including linolenic acid as flaxseed oil in milk have a positive effect on the performance, growth and health during the first month after birth of dairy calves.

The aim of the present experiment was to determine the effect of using the vitex agnus-castus (vitex) leaves as an alternative for alfalfa hay in the diet of fattening male goat kids on the performance, ruminal fermentation, digestibility of the nutrients and some blood parameters. The experimental treatments were 1) control (without vitex) and 2) replacement of vitex leaves with 60% alfalfa hay in the control diet(equal to 18% of diet). Sixteen fattening male goat kids with the average weights of 18 ± 2 kg and ages of 4.5 months were randomly assigned to the two treatments and eight replications for 60 days. Feed consumption, weight changes and feed conversion ratio were measured every 15 days. Dry matter intake, digestibility of nutrients, daily weight gain and feed conversion ratio were not affected by theexperimental treatments in the entire experiment period. Compared to the control diet, concentrations of blood urea nitrogen (P =0.08) and cholesterol (P =0.07) tend to decrease whereas blood glucose concentration (P=0.08) tend to increase in the kids fed with the diet containing vitex leaves. Ammonia nitrogen concentration and pH of the rumen liquor in treatment containing vitex leaves were significantly lower compared to the control group (P <0.05). Consequently, the vitex leaves can be used up to 18% of diet in the feeding of fattening male goat kids as an appropriate replacement for 60% of alfalfa hay without having the negative effects on their digestion and performance.

The aim of this study was to determine the effect of different energy intake before the peri-partum period on performance and some metabolic parameters in Ghezel newborn lambs. In this study, 15 mature Ghezel ewes after ultrasonographic confirmation of singleton pregnancy were used from 30 days prior to 30 days after lambing. Dietary treatments included: The control group with a diet that supplies 100% energy requirement of the animal, ewes under diet 70% (30% lower than animal energy requirement), ewes under diet 130% (30% higher than animal energy requirement). The amount of colostrum production and composition, daily milk yield, milk composition per week, birth weight, daily weight gain, and milk consumption in lambs were measured. Some plasma parameters immediately after birth, 24 hours later from birth and weekly until one month in lambs have been determained. The data obtained from this study on production and composition of milk showed that the diet 130% can increase the milk production (P<0.05). Colostrum production was significantly increased in  group fed with 130% energy level (P<0.05). However, in the 70% group, colostrum and milk production significantly decreased and the fat percentage has been increased (P<0.05). There was a significant difference between treatments of 130٪ of energy intake and other treatments in lambs weight, daily weight gain, and milk consumption so that the highest weight of lambing was in 130% group. There were no significant differences between treatments in aspartate aminotransferase (AST), alanine aminotransferase (ALT) and triglyceride (P>0.05). There was a significant difference between the treatments in relation to the immune system of lambs (P<0.05). The highest levels of immunoglobulin G and the lowest levels of plasma cortisol were observed in 130% group. It could be concluded that the high energy level intake in pre-parturition period, has led to an increase on ewe performance for produce heavy lambs, more milk and colostrum production, increase daily weight gain and high level of immunoglobulin G in lambs.

The aim of this study was to evaluate the effect of three sources of chromium (Nano-Cr, Met-Cr and Bonza-Cr) on growth performance, ruminal fermentation, some blood metabolites and rumen protozoan population in Mehraban fattening lambs. Twenty-eight lambs 7 month of age (mean body weight of 27.30 ± 3.98 kg), were randomly allocated to four dietary treatments for 63 days during winter season, -6 to 15 centigrade, using completely randomized design. The feed conversion ratio of Cr supplemented groups were not different from that of control group (P=0.11). The gas production, organic matter degradability and metabolizable energy in lambs receiving Met-Cr and Cr-Bonza on day 60 were higher than those of other groups (P˂0.001). The ammonia nitrogen decreased (P˂0.05) in lambs receiving Met-Cr and Bon-Cr compared to other groups on days 40 and 60 of experiment. Total volatile fatty acids of rumen liquor of lambs supplemented with Cr were increased (P=0.03) compare to control on day 40 of experiment. The protozoa count did not influence due to incorporation of Cr to diet (P>0.05). The serum albumin of lambs received Nano-Cr and blood urea concentration of Cr supplemented animals were affected (P<0.05). The overall results indicated that the addition of Met-Cr and Bonza-Cr increased the growth of lambs, but it did not affect the population of protozoa and gross profits.

The objectives of this study were to identify a suitable mathematical method for describing the growth traits of Mahabadi goat. Thereafter, four non-linear growth function of Brody, Gompertz, Logistic and Von Bertalanffy were applied. Growth curve analyzed based on weekly records of live weight form birth to 105 days of Mahabadi goat breed. Growth models were fitted to a total of 2036 weight-age data belonging to 126 kids. The growth models were compared by using the coefficient of determination (R2), Root mean square error (MSE) and Akaike information criterion (AIC). Among all non-linear models, the Brody function had the smallest AIC and MSE values and the higher R2 value, indicating the best fit for Mahabadi breed growth data. Average of birth weight, weaning weight (105days old) and pre-weaning average daily gain (ADG) for Mahabadi goat were3.25kg, 13.5kg and 0.092kg, respectively. The results of this study can help farmer to management strategies and make decision in selection and culling of kids through the growth curve.

Early-weaning of lambs could led to improve the efficiency and profitability of Baluchi ewes and lambs in Iranian sheep husbandry. Early weaning of lambs can stimulate growth of gastrointestinal tract, minimize weaning stress and guarantee post-weaning health. However, results on weaning age of lambs vary widely because of the effects of available feeds, feeding management and genotype. Iranian rural and nomadic herders are usually weaning their lambs when the pastures are in good condition. Reducing the duration of suckling lamb can be associated with optimal results, including sales of surplus milk of ewes and helping the herder household’s economy and entering the early weaned lambs into the feedlot systems and breed the ewes in a well-controlled condition. The aim of this study was to determine the appropriate weaning age of Baluchi lambs to achieve the better production and economic performances as well as the higher ewe's reproductive efficiency. Thirty monoparous Baluchi ewes in their second lambing with an average body weight of 47± 0.5 (Kg) and their lambs (15 males and 15 females with an average birth weight of 4.5 ± 0.05 Kg) were allocated to the experimental groups randomly. The lambs were left with their mothers for 3 days, in order to consume adequate colostrum and then were divided into 3 groups according to their gender (5 males and 5 females in each group) and kept in individual boxes. The experimental ewes were also kept separately in individual boxes. These lambs were allowed to be with their mothers twice a day for 2 hours. Lambs had free access to water and TMR ration including 10% Alfalfa leaves and 90% concentrate. Ewes also had free access to water and a TMR ration containing 65% alfalfa hay and 35% concentrate. The respective lambs were weaned at ages of 4, 8 and 12 weeks, abruptly and fed with the above noted TMR ration. The birth weight of each lamb and the weight of ewes were recorded at birth and until the end of the test weekly, each of the ewes and lambs were weighed individually before morning feeding. During the experiment, every two weeks, samples were taken from forage, consumed concentrate and existing residues, and their dry matter and nutrient content were determined. The average daily weight gain, weight fluctuations, dry matter intake, milk consumption and blood parameters at age of 12 weeks in lambs, weight fluctuations, dry matter intake at weaning time in ewes and benefit to cost ratio were measured. Data were analyzed with Proc GLM of SAS (9.1) software in completely randomized design. Based on the results, early weaning of lambs at age of 4 weeks led to a significant (P<0.05) improvement in average daily weight gain, body weight, dry matter intake, reduction in milk consumption at the end of week 12 by lambs, and improvement in body weight and dry matter intake at the weaning time by ewes. Also, the daily milk consumption of lambs showed that the production of milk decreased gradually from the ninth week after lambing. ALP enzyme levels and IGF-1 hormone in serum of lambs weaned at age of 4 weeks were higher in comparison with the other 2 groups. In this experiment, the average cost of feed for lambs weaned at age of 4 weeks was significantly higher than the other two groups, and in the ewes, this ratio was in contrast. On the other hand, the average cost of milk consumed by lambs in the three groups was completely reverse the feeds and the differences between groups were significant. The cost of labor was also significant in the groups due to the variability of the number of days. Average weight loss of ewes from lambing to weaning their lambs at age of 4 weeks was significantly lower than the other two groups. The average benefit from lamb weight gain in the group weaned at age of 4 weeks was significantly higher than the other two groups. Also, the benefit from ewe weight gain from the weaning to mating (2 weeks after weaning) was significantly higher in the ewes weaned their lambs at age of 4 weeks than in the other two groups. The benefit to cost indicator showed weaning of lambs at age of 4 weeks could be a suitable and economical management practice in rural and nomadic situation in sheep industry. The obtained results revealed that early weaning of lambs (at age of 4 weeks) may be regarded as a method of lambs and ewes' management in Iranian sheep husbandry. Preparing ewes for the next pregnancy and reducing the lambing interval are the noticeable results. The offered feeds can be used efficiently, and ewe's readiness for the next pregnancy increased by lowering metabolic stress. Furthermore, according to the benefit to cost ratio indicator, better economical outcome could be resulted.

Improved efficiency in the use of animal feed is important. The use of algae extract (Tasco) in domestic animal feeding improves digestibility of the diet and consequently increases production and profitability. This feedstuff is used as a source of vitamins to increase economic longevity of livestock, and the use of this substance plays a role in reducing the effects of heat stress. Ascophyllum nodosum is an algae that has several uses, including increasing the digestibility of fibrous materials. The present experiment was conducted to investigate the effect of using an extract of Ascophyllum nodosum algae (with Tasco brand) on feed digestibility and finishing performance of buffalo calves. Fifteen buffalo calves (262±18 kg) were allocated to three treatments as a completely randomized design. The experimental treatments were including 1- basal diet without supplement (control diet), 2- basal diet supplemented with 1% Tasco, and 3- basal diet supplemented with 2% Tasco. Dry matter intake and ort was recorded daily and live weight each fifteenth days. The average daily gain, feed conversion ratio, and feed performance were calculated. The digestibility of feed nutrients were measured by total feces collection method. The average feed intake of the whole period of experiment in control and treatment containing 1% Tasco was highest and lowest amount, respectively. The treatment containing 1% Tasco had the highest final weight and weight gain from day 0.0 to 75 and 30 to 60 of the experiment (P<0.05). In comparison to control, feed conversion ratio in treat contains 1 and 2% Tasco was improved about 21 and 25%. The treatment containing 1% Tasco showed the most suitable feed conversion ratio (P<0.05). In comparison to control, supplementation of diets with Tasco, significantly increased the intake and digestibility of NDF (P<0.05). The digestibility of crude protein and NDF was increased linearly with increasing amount of Tasco in the diet (P<0.05), compared with control the most percentage was belonged to treat containing 2% of Tasco. According to the results of present experiment, using Tasco had beneficial effects on performance and digestibility of nutrients in finishing buffaloes and for performance diet containing 1% compared to 2% Tasco and control diet had the best results. Therefore, it may be beneficial to use Tasco especially in finishing livestocks. According to the results of present experiment, using Tasco had beneficial effects on performance and digestibility of nutrients in finishing buffaloes and for performance diet containing 1% compared to 2% Tasco and control diet had the best results. Therefore, it may be beneficial to use Tasco especially in finishing livestocks.

Average daily gain (ADG) is the most economically important trait in sheep industry.
In genome wide association study and genomic selection, determining of extent and level of linkage
disequilibrium (LD) and haplotype block structure are critical in sample size and marker density. Haplotype blocks are defined as long stretches of SNPs along a chromosome that have low recombination rates, which characterized by relatively few haplotypes. Understanding haplotype structure in genome can greatly facilitate LD analysis. Haplotype-based association analysis can offer a powerful approach for mapping functional genes (Gabriel et al., 2002). Therefore, the objective of this research were to study LD pattern, determine haplotype block structure and genome wide haplotype association study in Zandi sheep for identifying the genomic region associated with pre-weaning (AGW) and post-weaning daily gain (PWG). A total of 96 Iranian Zandi sheep were used in the study. The following two traits were analyzed: pre-weaning daily gain and post-weaning daily gain. Animals were genotyped using 50 K SNPChip panel. Quality control of the genotype data consisted in removing SNPs with a call rate less than 95 %, SNPs with a minor allele frequency (MAF) less than 5 %, individual with more than 10 % missing genotypes, and SNPs that deviated strongly from Hardy–Weinberg equilibrium (P < 10−6). LD between all pairs were calculated with r2 by PLINK v1.07. Haplotype blocks were identified on base algorithm Gabriel et al. (2002) for all autosomes, using Haploview software (Barrett et al. 2005), based on estimates of D' for all pairwise combinations of SNPs within each chromosome. Following Gabriel et al. (2002), a pair of SNPs is defined to be in “strong LD” if the upper 95% confidence bound of D' is > 0.98 (consistent with no historical recombination) and the lower bound is > 0.7. Using the Haploview default values for blocks (Gabriel et al. 2002), a haplotype block is defined as a region over which 95 % of informative SNP pairs show “strong LD”. The PLINK was used to generate the matrix using the GLM algorithm. In this analysis, because of the previous selection history of the flock, it was important to identify and correct for population stratification. To evaluate whether estimates were overinflated, we used the genomic inflation factor λ using the PLINK software (Purcell et al., 2007). We also assessed their deviation from the expected distribution of no SNPs being associated with the trait of interest using a quantile-quantile (Q-Q) plot, which is commonly used to analyze population stratification in GWAS. We use SNPEVG tool to show the (Q-Q) plot. The Bonferroni method was used to adjust for multiple testing from the number of SNP loci detected. We declared a significant SNP at the genome-wide significance level if the raw P-value was, 0.05/N, here N is the number of SNP loci tested in the analyses. Therefore, for each trait, the threshold P-value for declaring genome-wide significance was (0.05)/40,879=1.2×10-6. The exact positions of the annotated genes were extracted from the latest sheep genome Oar_v4.0 assembly along with the NCBI annotation release 102 of the sheep genome. To investigate whether the
significant SNPs detected in this study were within the range of previously identified QTL for relevant traits, we searched for meat or production QTL in the Animal QTLdb within a 1-Mb region on both sides of each significant haplotype. After quality control, 2 individuals were excluded, leaving 94 sheep for the association analysis. Additionally, we removed 1070 SNPs with call rates less than 95% and 7717 SNPs with MAF less than 0.05. A total of 40,879 SNPs passed these quality-control filters and were retained in the dataset. These SNPs were distributed across 26 autosomes, with the number of SNPs per chromosome ranging from 747 to 5694, and with a mean distance between adjacent SNPs ranging from 50.4 to 68.7 kb. Also, in this study, the extent of LD was 40 kb with r2=0.2. Overally, 1472 blocks were observed in the 7.58% of all SNPs were classified into haplotype blocks, covering 1.45% of the total autosomal genome size. The results showed a reduction in LD level with the increase in distance between markers. The average pre-weaning daily gain was 0.197±0.04 kg with an individual sheep range of 0.08-0.34 kg. Average post-weaning daily gain was 0.126±0.07 kg with an individual sheep range of 0.03-0.41 kg. The result from genomic control showed weak population stratification for AGW and PGW in between population of Zandi sheep. The genomic inflation factors (λgc) for the two traits were equal to 1.039 and 1.073, for AGW and PGW, respectively. However, as the Q-Q plots clearly show, there is no evidence of any systematic bias (λgc˂1.1) due to population structure or analytical approach in our case. Considering the significant fixed effects in the genomic wide association analysis, four haplotypes on chromosomes 3, 5, 6 and 7 identified to affect significantly AGW and PWG traits. The results of this study could provide a suite of novel SNP markers and candidate genes associated with growth traits and hence, may play an important role for understanding the biology of average daily gain in sheep.

A large part of animal performance is under effect of the dietary nutrient level and the balance of nutrients in the feed consumes a great deal on the yield of the farm animals. Studies on ruminant’s nutrition have shown that diets containing high levels of concentrate can increase the growth rate and increase the production level. Also it has been reported that high energy diets have improved the feed conversion rate. Despite its importance there is no much information about response of Iranian sheep, especially fatty tailed breeds to nutrient requirements estimated by new nutritional systems. Therefore, the aim of this study was to investigate the effect of two dietary treatments with energy level recommended by SNRS (2.25 ME cal/Kg) and 10% higher (2.5 ME cal/Kg) on growth performance and blood parameters of two Iranian breed lambs. This study, was conducted in completely randomized blocks design with two treatments (2 level of dietary energy) and two blocks (Zel and Afshari breeds) using 20 lambs with a mean body weight of 20 and 28 kg respectively in a 150 day period, during which time feed intake and the feed residues were weighed at the beginning and the end of each day, and each 14 days, lambs were regularly weighed. In order to investigation of the blood parameters, Blood samples were collected from the venous veins of the lambs 4 times (on days 10, 30, 50 and 70). Finally, the parameters of triglyceride, cholesterol, HDL, and LDL were measured. Statistical analyzes were performed using SAS version 9.2. Lambs receiving High energy diet showed more weight gain. According to the results, Zel and Afshari breeds in this treatment had 24 and 34 grams, respectively, more weight gain than the low energy treatment, which was statistically significant in Afshari lambs. Also, the feed conversion rates of lams receiving High energy diet were 0.7 and 0.9 units lower respectively. The results of the analysis of blood parameters showed that increase in dietary energy in Afshari lambs, increased blood glucose and triglyceride levels, and the cholesterol, LDL and HDL levels were decreased significantly with decreasing dietary energy level in both breeds. Based on the results of this study, it can be said that using the energy level higher than the recommendations for Afshari lambs results in improvement of feed conversion rate, which is associated with an increase in the weight gain, hence, can improve the income earned by the farmer.

Mutton production in Iran, as the main source of red meat, does not satisfy the increasing demand of the consumers. Estimation of genetic parameters of economic important traits are necessary for determining breeding goal and selection index. In this study, data were collected from 1996 to 2014 at the Makooei Sheep Breeding Station (Makoo) in west-Azerbaijan province were used to estimate the genetic parameters for growth traits and Kleiber ratios. Traits studied were birth weight (BW), weaning weight (WW), six month weight (6MW) and yearling weight (YW), Average daily gain from birth to weaning (ADGa), Average daily gain from weaning to six months of age (ADGb), Kleiber ratio from birth to weaning (KRa), and Kleiber ratio from weaning to six months of age (KRb). (Co) variance components were obtained fitting different animal models using a restricted maximum likelihood (REML) procedure via ASREML program. The most appropriate model for each trait was determined based on log likelihood ratio tests. The most appropriate model for birth weight trait model 3 (direct and maternal genetic effects, without considering covariance between them), weaning weight, six month weight and Average daily gain from birth to weaning Model 2 (direct additive genetic effects and maternal permanent environment) and yearling weight, Average daily gain from weaning to six months, Kleiber ratio from birth to weaning, and Kleiber ratio from weaning to six months of age Model 1 (direct effects). Direct estimate of heritability for BW, WW, 6MW, YW, ADGa, ADGb, KRa and KRb was 0.15±0.04, 0.16±0.03, 0.21±0.04, 0.22±0.06, 0.13±0.05, 0.14±.04, 0.06±0.03 and 0.03±0.02, respectively. The estimate of maternal heritability for BW was 0.08±0.02. Genetic correlations were ranged 0.13 (between YW with KRb) to 0.94 (between WW with KRa). The results of this study indicated that selection for Kleiber ratio can result in genetic improvement of growth rate as well as feed efficiency.Genetic parameter estimates of local breeds are important. Genetic parameter estimates of local breeds are important for conservation purposes, defining breeding objectives, and programs. The traits having economic value such as growth
rate and Kleiber ratio are influenced by individual direct genetic, maternal effects, and environment which animal is raised Profitability of a sheep production system can be influenced by growth rate of the lambs in different ages. Normally, the lambs having more growth rate are more capable of reaching market weight. Growth rate is defined as the average daily gain of an individual in a specific period and can be classified as from birth to weaning, from birth to 6 months of age, from weaning to 6 months of age

Introduction Animal nutrition, accounted as significant portion of the animal husbandry costs. Dry and semi-arid climate and lack of rainfall in Iran has caused difficulty in preparation of inexpensive feed for ruminant animals. Therefore, one way to overcome limitation of forage resources and the high cost of livestock feeds is use of agricultural by products such as mung bean straw or other unconventional sources of the feed. Irrigated cultivation of mung bean in Iran distributed in Azerbaijan, Khorasan, Isfahan, Fars, Khuzestan and northern provinces, and rainfed cultivation in the foothills of Gorgan. Most nutritional studies, conducted with the mung bean, but just few studies have been done on its straw. Therefore, the present experiment was conducted to finding the effects of mung bean straw on digestion and sheep fattening performance when it was replaced by wheat straw or low grain-corn silage in diet of Arabic lambs.
Materials and Methods After determining the appropriate level of replacing mung bean straw with wheat straw and corn silage using the in vitro two steps digestion method, in the second step of study the lambs, fed selected diets from first step, included: diet without mung bean straw (control ration), 100% replacing of mung bean straw with wheat straw (diet 1), 25% and 50% replacing of mung bean straw by corn silage (diets 2 and 3, respectively) as a completely randomized design. For determination of nutrients digestibility, the amount of feed intake, ort and fecal excretion was recorded. In order to estimate blood and rumen fermentation parameters, and rumen protozoa population count at the end of the experiment, rumen fluid and blood was taken from the lambs after the morning feeding. The weight of lambs was recorded at initial, final of experiment, also every fifteen days. Feed conversion ratio and feed efficiency was calculated.
Results and Discussion The result of first step, determining the appropriate level of digestibility, was showed that there is no difference between the experimental diets for nutrients digestibility. According to the in vitro results, amount of feed intake was different between rations and in diets containing mung bean straw (diets 1 and 3 exception 2) was more than the control, diet 1 had the highest nutrients digestibility. The experimental diets had no effect on blood and rumen parameters. There was no significant difference between the diets for the average daily gain and feed conversion ratio in whole period of study. About 30-40% of rumen microbial digestion of fiber, done by protozoa population, also 34% from cellulolytic activity of the rumen is belonging to the protozoa. The fiber degradability significantly decreases by defaunation of rumen, so it is possible that more digestibilities of NDF and ADF in the diet containing 100% replacement of mung bean straw by wheat straw (diet 1) was related to more rumen protozoa population of this diet. Also, lower amount of pH, even non significant, in control diet, no. 2 and 3, may be caused to decrease their digestibility, because proper growth of cellulolytic bacteria and protozoa take place in pH 6.7 and when pH falls under 6.2, the significant decreases in digestibility of fiber will be happened and fiber decreasing continued by falling of pH. In the other hand, rumen protozoa have the ability for stabilizing the rumen pH, which is probably due to the rapid digestion of starch and stored by ciliated protozoan. So, perhaps the more population of fiber digester strains such as Entodinium in diet 1 improves its digestibility.
Conclusion Therefore, according to the results of present study, there were no difference in the finishing performance and nutrients digestibility of lambs, also these traits were even better in some cases such as feed intake (0-45 day), gain (0-15 and 0-30 day) and feed conversion ratio (0-15 day), so the use of mung bean straw because of its abundance and relatively cheapness at the particular season of the year, the replacement of it by wheat straw or low grain-corn silage in the feeding of lambs is recommended.

Introduction Kurdish sheep breed is one of the most important native breeds of Iran. They are fat-tailed, large-sized, well adapted to the mountainous regions in northern Khorasan province and mainly raising for meat production under pastoral production system (28). Feed efficiency is a major component in the profitability of the small ruminant enterprise, because quality of range and pasture is low in poor environmental conditions in Iran. Growth rate and feed efficiency are two traits of great economic importance in sheep production and also Kleiber ratio has been suggested to be a useful indicator for these traits (2). There was no information regarding genetic parameters for growth traits in Kurdish sheep. Thus, the main objective of the present research was to estimate (co)variance components and genetic parameters for pre- and post-weaning growth traits and Kleiber ratio in Kurdish sheep.
Material and Methods In this study, the records of growth traits from 5144 lambs (from 161 rams and 1982 ewes) were used. The data were collected during a 17-year period (1996–2013) in Kurdish sheep Breeding Station located in Shirvan city of northern Khorasan province. Traits investigated were average daily gain from birth to weaning (ADG0-3), average daily gain from weaning to six months of age (ADG3-6), average daily gain from six to nine months of age (ADG6-9), average daily gain from nine to twelve months of age (ADG9-12) and Kleiber ratios (KR) defined as: KR1=ADG0-3/(BW3)0.75
KR2=ADG3-6/(BW6)0.75
KR3=ADG6-9/(BW9)0.75
KR4=ADG9-12/(BW12)0.75
Test of significance for the fixed effects to be included in the final functional model for each trait and calculation of least squares means was accomplished using GLM procedure of SAS software (24). The considered fixed effects were year of lambing (1996-2013), sex of lamb (male and female), type of birth (single and twin) and age of ewe (1–7 years old). (Co) variance components and genetic parameters were estimated applying restricted maximum likelihood (REML) method fitting six animal models using WOMBAT (18): y =Xb斦 Model 1
y=Xb斦빦鞩篧 Model 2
y =Xb斦빦榾 Cov(a,m)=0 Model 3
y =Xb斦빦榾 Cov(a,m)=Aσam Model 4
y =Xb斦빦榾暗ꥻ Cov(a,m)=0 Model 5
y =Xb斦빦榾暗ꥻ Cov(a,m)= Aσam Model 6
where y: is a vector of records, b: is a vector of fixed effects, a: is a vector of direct additive genetic effects, m: is a vector of maternal additive genetic effects, pe: is a vector of permanent environmental effects due to ewe, X, Za, Zm and Zpe are corresponding design matrices relating the fixed effects, direct additive genetic effects, maternal additive genetic effects and permanent environmental effects due to ewe to vector of y, respectively, e: is a vector of residual effects, and Cov(a,m): is the covariance between direct additive genetic and maternal additive genetic effects.
Akaike’s Information Criterion (AIC) was used for selecting the best model among the tested models (3): Where logLi: is the maximized log likelihood of model i at convergence and pi: is the number of the parameters in each model. Model with the lowest AIC was considered as the best model for each trait. Estimation of genetic and phenotypic correlations was accomplished using multi-trait analysis (with model 1). The fixed effects included in the multi-trait animal models were those in single-trait analyses.
Results and Discussion The pre-weaning average daily gain in Kurdish lambs was 215.33±0.96 g, while this trait in post-weaning periods had a decreased trend. These values (especially in pre-weaning period) indicated that Kurdish lambs have a good potential for growth. Results from the analysis of variance of ADG and KR in different ages showed that birth year and sex of the lambs significantly influenced studied traits (PConclusion It was observed that maternal genetic models could better explain the genetic variation observed in pre-weaning traits. Estimates of phenotypic and genetic correlations among ADG and KR traits were high in magnitude. These results suggest that selection for Kleiber ratio can result in genetic improvement of growth rate as well as feed effeciency.

The study was designed to investigate the relationship between growth trait and biometric traits in Baluchi sheep. This study was conducted to estimate the genetic and phenotypic biometric traits including daily gain (ADG) and height at withers (HW), height at back (HB), body length (BL), heart girth (HG), leg girth (LG) and testis girth (TG) in Baluchi sheep. Total data of 4542 records from six experimental herds of Jahad Organization Research Centre of Mashhad County were collected since 2001 to 2011. Data were analyzed using General Linear Model (GLM) of SAS. For the estimation of genetic parameters and genetic correlation between traits, animal model uni and multi-trait by restricted maximum likelihood (REML) of WOMBAT 32 (Meyer 2007) have been used. The mean heritability of ADG, BL, HG, HW, HB, TG and LG traits was estimated 0.13±0.01, 0.11±0.06, 0.21±0.07, 0.17±0.06, 0.32±0.1 and 0.2±0.06 respectively. The results of the current study showed that the TG trait has the highest heritability. The estimations shows genetic improvement will be predictable in biometric traits of Baluchi sheep. The genetic correlation between traits was positive, ranged between 0.15-0.97. Moreover, phenotypic correlation was positive and was estimated in range of 0.32 to 0.94.

Estimation of genetic parameters of economic important traits are necessary for determining breeding goal and selection index. In present study, the genetic parameters of average daily gain from birth to weaning (ADGa), from weaning to 6 month of age (ADGb) and from 6 to 9 month of age (ADGc) and Kleiber ratio at weaning (KRa), at 6 month of age (KRb) and at 9 month of age (KRc) were estimated. The data set included 12701 records of rural flocks under supervision of Ghezel sheep breeding station located in Western Azerbaijan province and collected over the period from 1994 to 2009 were analysed by Restricted Maximum Likelihood (REML) procedure using WOMBAT software. Fixed effect of Herd - year of birth (HY) was significant on all traits. Effect of sex was significant on all traits except for KRa and effect of litter size was significant for all traits except for KRb. Effect of dam age was significant on ADGc, KRb, only. Model 1 (contains direct additive genetic effect) was the best model for ADGc and KRc and model 7 (contains direct additive genetic and maternal common environmental effects) was the best model for the other traits. Direct heritability of the ADGa, ADGb, ADGc, KRa, KRb and KRc based on the best model were 0.27, 0.18, 0.14, 0.22, 0.13 and 0.16, respectively. The proportion of maternal common environmental variance to phenotypic variance (c2) for ADGa, ADGb, KRa and KRb were 0.52, 0.16, 0.52 and 0.19, respectively. Direct heritability of Average Daily Gain and Kleiber ratio in studied rural flocks were moderate. Therefore selection specially based on KRa will be effective for these traits. Moreover, including maternal common environmental effect in animal models for accurate estimation of direct heritability in this breed is recommendable.