ANIMAL SCIENCE AND RESEARCH JOURNAL
Year:2009 | Volume:3 | Issue:-|Papers Count:15

In order to study of variance components, heritability and genetic correlation of some economic traits, were used collected data during 2004-2007 in hybrids of six lines of silkworm. In all hybrids, cocoon weight heritability was higher than cocoon shell weight’s heritability. Heritability of cocoon shell percentage was lower than other traits. There was a high and positive genetic correlation between cocoon weight and cocoon shell weight and there was a low genetic correlation between cocoon weight and cocoon shell percentage. Heterosis effect on means of cocoon weight and cocoon shell weight was positive and increase in heterosis percentage increased means of this traits. Along increase in recombination percentage in cocoon shell percentage, mean of this trait increased. The results showed that there was an inverse relationship between heterosis and recombination effects. Also genetic gain and means of traits in 31, 32 and their hybrids were upper than others hybrids. So it is expected that the use of these liens is better in commercial level.

To study the fleece characteristics of native goats in Lorestan province, fiber sample was taken from 29 and 45 female and male kids and adult goats. The least square means were generated with two-way model. Results indicated that significant different was found between sex and ages for fleece weight and hair staple length. Fleece weight and hair staple length in male and female were 527.98±34.32 and 344.44±28.44 gr, 9.62±0.66 and 7.82±0.56 cm res. The above characteristics in kids and adult goat were 365.50±33.46 and 507.93±29.19 gr, 7.21±0.67 and 10.23±0.55 cm res. Different ages also had significant different on mean hair fiber diameter, coefficient of variation of diameter and fiber lengths. The fiber diameter, CV of fiber diameter and lengths in kids was (76.62±2.63 mm, 21.88±1.20 percent and 5.32±0.44 cm), that finer than adult goats (86.29±2.31 mm, 25.29±1.06 percent and 6.89±0.36 cm) res. The dark color, low down fiber percentage and long length in Lorestan goats fleeces introduce them to produce good coarse hair fibers.

Weight, Heart girth, Stature and Scapulatial length in 3000 heads of Farahani sheep breed consisting of five age classes and 30 herds was recorded. Age, sex and herd were significant effects on weight and database was corrected for these effects. All regressed equations were significant. To select best fitting model, coefficients of determination (R2) and error mean square (MSE) of all models were compared. Model involving Heart girth, Scapulatial length and Stature best fitted the weight components. This model had R2 and MSE equal to 0.99 and 0.779 respectively. Largest phenotypic correlation was found between Weight and Heart girth and between Stature and Scapulatial length each 0.978 and 0.995 respectively. The least phenotypic correlation was found between Scapulatial length and Heart girth.

In order to study the nutritive value of Citric Acid production residue (CAPR) and the effect of using it on broiler chicken performance this experiment was conducted in completely randomized Design with 5 treatment (0, 2.5, 5, 7.5, 10 percent of CAPR) in 6 replicate and 14 broiler chicks (male and female) in each replicate with Arian strain at 7-49 days. At first, metabolism energy of CAPR were determined with Sibbald method and experimental Isonitrogenous and Isocaloric diets were prepared. In this experiment Feed Intake (FI), Weight Gain (WG), Feed Conversion Ratio (FCR) were evaluated every week and Mortality Percentage, expense of Feed Consumption for one Kg body Weight and Production Index(PI) were evaluated in total period.The results showed that maximum feed intake in total period was related to treatment of 7.5% CAPR and minimum was related to 2.5 % CAPR and control diet. The effect of different treatment on average of weight gain was significant in grower and finisher period (P<0.05). In total period; the maximum average of weight gain was related to treatment of 5 % and minimum average for treatment of 10% CAPR. In concern to feed conversion ratio, the difference between treatment was significant just in 1-21 days (P<0.05). In total period, the maximum feed conversion ratio was related to treatment of 10% CAPR and minimum was related to the treatment of 2.5% CAPR and control diet too. There were any significant differences between treatments about mortality percentage. In total period, the maximum average of production index was related to control treatment and treatment of 2.5% and the minimum amount of that was related to the treatment of 10% CAPR (P<0.05). Expense of feed intake for each Kg of body weight between different treatments was significant (P<0.05). The maximum average of feed expense was related to the treatment of 10% CAPR and minimum average of feed expense was related to control treatment. According to obtained results, level of 5% CAPR is suitable to use in broiler chick diets.

An experiment was conducted to determine effect of different feed deprivation in the growing period (11 to 28 days) on ross broiler performance. 300 one-day old chicken were distributed randomly to 20 pens in a completely randomized design with 5 treatment *4 replications and were grown for 42 days. 5 treatment groups included:1-ad libitum group. 2-2 h deprived group. 3-4 h deprived group.4-6 h deprived group.5-8 h deprived group. Chickens were fed by 1 corn soy based diet formulated according to Ross recommendation .Weight gain , feed consumption, feed conversion ratio were measured periodically and the end of experiment one chick was selected from each pen and slaughtered to measure carcass traits.There was no significant difference between weight gain, feed consumption and feed conversion ratio of treatment from d 0 to 42 ( p³0.05) but feed consumption in growing period (d 11 to 28 ) were significantly different between treatments (p<0.05) so that the 6h deprived group (treatment 4) show significantly more feed consumption than the 8h deprived group (treatment 5).Analysis of carcass traits showed no significant difference between treatments related to skeleton percentage, gizzard percentage, abdominal fat percentage, liver percentage, breast percentage, leg percentage, pancreases percentage, intestine percentage and heart percentage (p³0.05).European production index results indicate no significant difference between treatments (p³0.05).

This experiment was conducted to determine the effect of nutrient analysis tables of ingredient on Ross strain broiler performance. This experiment used CRD design. Chicks were grouped in to three treatments with six replications and each with 15 chicks. The experimental treatment consisted: 1) Diet formulation according to analysis table of NRC. 2) Diet formulation according to analysis table of FEEDSTUFF and 3) Diet formulation according to analysis table of DEGUSSA. Feed intake (FI), Average daily gain (ADG), Feed conversion ratio (FCR) and Production index (PI) were measured. The cost of feed per1kg of weight and carcass characteristics were also compared. According to the result the body weight among different treatments was significant (p<0.05). The highest final weight was obtained with NRC analysis table. Feed intake among treatments was not significantly difference (p>0.05). There was significant difference in feed conversion among treatments and NRC analysis table was resulted the lowest FCR. Production index among treatments was significantly difference (p<0.05). The cost of feed per 1kg weight among treatment was not significant (p>0.05).Finally, with respect of all parameters, the best treatment was NRC analysis table.

This study carried out to investigate the effects of soybean fatty acids and soybean calcium salt fatty acids on broiler chicken performance, carcass yield, pancreas and abdominal fat percentage. A total of 500 commercial crossbred of Ross was examined in 5 treatments and arranged on a completely randomized design (CRD) with 4 replicates per each treatment. Twenty five chicks were placed in each pen. The experiment lasted for 49 days. Neither soybean fatty acids nor soybean calcium salt fatty acids were used during the experiment in the first treatment. In the second treatment, for starter, grower and finisher period 0, 2.5 and 5 percents of soybean fatty acids were included respectively. During the third treatment 0, 2.5 and 5 percents of calcium salt fatty acids were used respectively, but in the fourth treatment 2.5, 5 and 5 percents of soybean fatty acids were used respectively, and in fifth treatment within the same period, 2.5, 5 and 5 percents of calcium salt fatty acids were used respectively. The results of the statistical analysis showed that there were significant differences in feed intake, weight gain and feed conversion ratio during the whole rearing periods (P<0.05). The results also showed significant differences among all treatments for carcass yield as well as pancreas percentage (P<0.05), and the use of soybean fatty acids and soybean calcium salt fatty acids had no significant effects on abdominal fat. It can be concluded from the results that the use of soybean fatty acids has precedence over calcium salt fatty acids on broiler performance.

Mastitis is an inflammatory immune reaction of the mammary gland, which is characterized by an influx of somatic cells into the milk. Bovine mastitis places a heavy economic burden on dairy sectors. In mastitis milk, microbial load and concentration of blood serum albumin, immunoglobulins,lactoferrin, sodium and chloride increase, whereas the content of lactose, casein, fat, different kinds of vitamins and minerals such as vitamin B1, B2, C, calcium, phosphorus, potassium and zinc decrease, and also intramammary infections cause an elevation of enzymatic activity of milk by increasing the concentration of different kinds of proteases such as plasmin, different types of cathepsin, elastase, and enzymes like lipase, b-glucuronidase, and catalase. These enzymes cannot be inactivated by thermal processing, thus they can affect the quality and shelf life of dairy products like yoghurt, milk powder, liquid pasteurized and UHT milk, and also enzymatic hydrolysis of casein result in decline in cheese yield. It seems that mastitis deteriorates the attributes of dairy products; therefore the main purpose of the present study is to review the importance of somatic cell count levels throughout the whole milk supply chain. It can be concluded that effective herd mastitis prevention and control programs on farm level in order to improve the quality of raw milk and dairy products, is essential.