مجله تحقیقات دام و طیور
سال دوم شماره 4 (1392)

This study was conducted to determine chemical composition, physical characteristics, digestibility, degradability and nutritional value of rose branches and alfalfa hay using in vitro and in situ techniques. Data were analysed by using t-test. Organic matter (OM), neutral detergent fiber (NDF) and ether extract of rose branches were significantly different from alfalfa hay (P<0.05). Effective degradability of dry matter (DM), OM and NDF of rose branches were not significantly higher than alfalfa hay. Digestibility of DM and OM of rose branches (53.30 and 52.36 percent, respectively) were not significantly higher than alfalfa hay (48.86 and 44.29 percent, respectively). Twenty four hours after incubation,gas production volume for rose branches was significantly higher compared to alfalfa hay (P<0.05). Moreover, soluble ash of rose branches was different from alfalfa hay (P<0.05). In conclusion, based on chemical composition, digestion kinetics and degradation data of rose branches, it can be used as a suitable forage source for partial replacement of alfalfa hay in animal ration.

The objective of this study was to investigate the suitable method for preparing sugarcane top (SCT) silage and evaluation the nutritive value of prepared silage by using in vitro methods in ruminant. The treatments were mixture of urea+molasses (1, 3 % DM, respectively) on two levels 0 and 1+3, sulfuric acid on three levels 0, 0.9 and 1.8 % DM that arranged in a 2×3 factorial design. The sugar cane top were mixed (DM basis) by additives and ensiled in polyethylene bags. Content of CPof SCT ensiled with urea+molasses and sulfuric acid increased (P<0.05). All additives significantly decreased pH of silage (P<0.05). The acid caused to increase NDF (P<0.05) and dry matter digestibility (P>0.05). Adding of sulphuric acid increased gas production linearly (P<0.05). All additives used in this experiment improved nutritive value of SCT silage, and made possible of long preservation. However, if pH decreases to lower than 4, silage quality remains the same as initial forage for a longer keeping time.

To evaluate antioxidant effects of tomato pomace in broiler diets contained full-fat linseed on the production index, energy and protein efficiency, 396 one-day old Ross 308 broilers were randomly allocated to 36 cages for nine dietary treatments with four replicate. This experiment were carried out in a completely randomized design with 3*3 factorial arrangement withthree levels of full-fat Linseed (0, 3 and 6% LS) and three levels of tomato pomace (0, 5 and 10% TP). Birds were fed with two diets of grower (10-24) and finisher (25-42d). Dietary contained TP and LS did not affect feed intake, body weight gain and feed conversion ratio. Supplementation of TP and LS to diets did not affect production index, Energy and protein efficiency of broiler chickens; however, the diets contained of 10% TP and 6% LS reduced the feed efficiency and production index of broilers at 28 d (P<0.05), with no effects on other parameters. In conclusion, supplementation of TP and LS to broiler diets may be with no effect onthe production index, energy and protein efficiency ratio, but the diets contained higher levels of LS (6%) and TP (10%) might reduce the energy efficiency and production index.

Camel production in Hormozgan province, Iran has a relative advantage over other livestock enterprises due to lack of pastures and arid lands. In this province, a number of camel service stations have been established in order to help camel owners improve their production. The cameleers of the stations take the camels to graze on available pastures every day and help better herd management. In this research, the effect of these stations on production parameters of camel herds of the private sector has been reviewed. To achieve this goal, some questionnaires were used. Two groups of herds were compared; group one being herds receiving stations services and group two receiving no services. Sirik and Jask are the main harbor cities known to have highest numbers of service stations in the province. Data were collected from these two cities and analyzed using SPSS and Microsoft Excel software. Results indicated that % 72.38 of beneficiaries were illiterate or have low level of educations. Average years of education were between 3-4 years. A significant difference between the average age of beneficiaries and herd size was observed (P<0.01). Some production parameters findings are as follows: increase in birth weight (P<0.01), increase in milk production (P<0.01), lower rate of mortality (P<0.01), average mature weight of herds (male and female) (P<0.05), lower rates of casualties due to predators (P<0.01), lower rates of road accidents and camel theft (P<0.01) were observed in the herds receiving services from the stations. While age at first calving (P<0.05), calving interval, weaning weight, length of lactation period and average of lactation period were not affected. It was concluded that the stations with control and partnership on camel herds can lower the mortality rates as well as improvement of production parameters drastically.

For this study, a total of 6,326 records of wool weight obtained from 273 rams and 1,927 ewes of Lori-Bakhtiari sheep were used. The data were collected in Shahrekord sheep breeding station (Sholi) during 1990-2011. SAS statistical software was utilised to determine the effect of environmental factors, and MTGSAM software via Gibbs sampling was applied to estimate genetic parameters. Environmental factors such as birth year, sex, type of birth, and age of mother had significant effect on the trait. The interaction between age of mother and sex of lamb, and interaction between type of birth and sex of lamb were significant. Animal’s age at shearing and birth weight were taken into account as covariates in the models. Using the best model, direct and maternal heritabilities for wool weight were 0.31±0.02 and 0.06±0.01, respectively. Direct and maternal genetic trends were 3.23±0.24 and 0.3±0.04 gr per year,respectively and statistically significant. Phenotypic and environmental trends were found to be 0.003 and -0.001, respectively but non-significant. Genetic progress was considerable at different years which could be due to breeding programs targeted at these stations.

An experiment was conducted in a 3×3 factorial arrangement (three different dietary protein levels: Cobb recommendation, 10 and 20 percents lower than that, and three types of feed formulations: 1- diet composed of corn and soybean as a control diet, 2-diet in which wheat, barley, wheat bran and poultry by-product mealwhich were substituted partially instead of corn and soybean of the first diet and its total sulfur containing amino acids, lysine and threonine were equal to total of these amino acids as per first diet and 3- diet which was similar to the second one but its digestible sulfur amino acids, lysine and threonine were equal to digestible amino acids in the first diet.In total, nine dietary treatments and four replicates of 10 chicks per eachtreatment were applied in a completely randomized design. Growth period of broilers was 28 days and they received starter diet at 1-10 days, grower diet at 11-24 and finisher diet at 25-28 days of age. The Interaction effect of diet type and dietary protein level on feed conversion ratio, production index, feed cost to gain and monetary returns per chickens was significant (P<0.05). As in diets formulated based on total amino acids a 10% reduction in dietary protein level resulted in a significant decrease in production index and monetary returns and increase in feed conversion ratio and feed cost to live weight however, in diets formulated based on digestible amino acids 10% reduction in dietary protein in spite of 20% reduction in dietary crude protein causes no significant difference in monetary returns, fed conversion ratio and feed cost to live weight in comparison with group their dietary crude protein was based on Cobb recommendation.

The objective of the present study was to estimate genetic parameters for weight, growth traits and Kleiber ratio in Zel sheep. Genetic and environmental (co)variance components were estimated using 1,664 records of Zel lambs collected during a seven-year period (2003-2009) in the Shirang breeding station, Golestan province, Iran. The traits under consideration were birth weight (BW), weaning weight, average daily gain and Kleiber ratio from birth to weaning. (Co) variance components and corresponding genetic parameters were estimated using univariate analysis fitting by six different animal models through restricted maximum likelihood (REML) method. The suitable model for each trait was determined based on Akaike information criterion (AIC). The estimated heritability of the birth weight, weaning weight, average daily gain and Kleiber ratio were 0.672± 0.146, 0.304± 0.086, 0.397± 0.088, and 0.134± 0.016, respectively. The estimated genetic trends for birth weight, weaning weight, average daily gain and Kleiber ratio, were -0.04824, 0.00062, -0.00062, and 0.04559, respectively.

The objective of this study was to detect mutation in intron 1 of myostatin gene using 110 individuals of Lori sheep breed. A 414-bp fragment of myostatin gene intron 1 was amplified and evaluated using PCR-SSCP. Five different SSCP patterns (genotype) and five alleles were observed. Frequencies of alleles A, D, C, E and F were 0.69, 0.19, 0.07, 0.02 and 0.03, respectively. Frequencies of genotype AA, AD, AC, AE and AF were 0.38, 0.36, 0.15, 0.05 and 0.06, respectively. Heterozygosity value was found to be 0.61. The chi-square test showed that the population has been deviated from Hardy- Weinberg equilibrium for the locus studied (P<0.05).