جستجوی مقالات مرتبط با کلیدواژه « Carcass characteristics » در نشریات گروه « دامپزشکی »

The present experiment was performed to compare the effect of different levels of dietary threonine on performance, carcass characteristics and immune system and blood factors in Japanese quailunder heat stress. For the experiment, 300 one-day-old Japanese quail chicks (Coturnix coturnix japonica) were used in a completely randomized design with six levels of threonine in 6 treatments and 5 replications, each replication containing 10 chicks. The percentages of threonine in the diet of the experimental treatments were: 1) 0.82 %, 2) 0.92 %, 3) 1.02 %, 4) 1.12 %, 5) 1.22 % and 6) 1.32 %. The results showed that the increase in body weight and feed conversion ratio improved significantly in treatments 5 and 6 (p < 0.001). Levels of 1.12 and 1.22% of threonine in the diet had a significant effect on carcass percentage (p < 0.001). There was no significant difference in the weight of lymphatic organs and the titer of antibodies produced against SRBC (sheep red blood cells) in the treatments (p>0.05). Dietary threonine levels had a significant effect on serum uric acid, HDL (high-density lipoprotein) and LDL (low-density lipoprotein) concentrations (p < 0.05). Liver enzyme levels were not significantly different in any of the treatments (p < 0.05). The results showed that increasing threonine in quail diet up to 1.22% can have beneficial effects on performance and improvement of carcass characteristics under heat stress conditions.

Ninty nine broiler chicks from Ross 308 strain at 21 days of age were randomly divided into three treatments and each treatment was divided into trireplicates and each replicate containing 11 chicks. The chicks were recieved water and three different diets with the same energy and protein levels free up to 42 days of age. Feed intake, weight, feed conversion ratio and mortality were calculated at the end of each week. At the end of the study, blood samples were collected and the different parts of the carcasses were separated and weighted. Experimental group 1 (Corn and barley-based diets (barley level 22%) and soybean meal, β-glucanase 2,600 IU/g, β-beta glucanase 1800 IU/g and cellulase 500 IU/g) had the highest production cost. There were statistically significant differences between experimental groups respected to proventriculus (P=0.002), abdominal fat (P=0.031), liver, gizzard and intestine ratio to alive weigh and average percent of carcass, breast and the thighs (P<0.0001). The highest carcass percent was observed in experimental group 2 (Receiver of corn, barley, β-xylanase 2200 U/g, β-glucanase 200 IU/g, cellulase 100 IU/g and pectinase 100 IU/g). The different groups showed no statistically significant differences in term of total protein and uric acid (P>0.05). However, the groups 1 showed statistically significant differences decreases for glucose and albumin in comparision to other groups (P<0.05). The findings of this study showed that the group that received lower levels of β-xylanase, β-glucanase and cellulase, with adding of pectinase, had better performance and lower production cost, which indicates a decrease in the effect of anti-nutritional factors on the recipients of this enzymatic complex.