carcass traits

Dietary protein plays an important role in ruminant nutrition, because in addition to providing amino acids, it’s a nitrogen source for microbial protein synthesis. Providing protein, especially for high-producing livestock, is one of the most important concerns of livestock farmers. Soybean meal has been used for a long time as an excellent source of CP for ruminants, but with the increase in its price, has challenge due to the limitation of production and direct consumption by humans. Due to the ability of ruminants to use NPN (urea), nitrogen unit density and its low price, it has been used as an alternative in ruminant diets. Urea is converted into ammonia in the rumen, on the other hand, fiber-digesting bacteria in the rumen need ammonia to growth. Hydrolysis of common urea is faster than the growth of microbes and the digestion of structural carbohydrates in the rumen, so it will reduce the efficiency of nitrogen use and even nitrogen poisoning in livestock. Slow-release urea (SRU) is a type of urea that slows release of nitrogen in the rumen. Substitution of SRU instead of common urea in the diet of ruminants that have a limit with protein sources can reduce the competition between humans and animals. Also, it will not have the dangers of common urea for livestock. This article review the effects of using SRU instead of common urea and plant protein sources in ruminants diet on feed intake, digestibility, fermentation parameters, growth and production, blood parameters and carcass characteristics.

Aflatoxin B1 is the most dangerous form of aflatoxins that could be produced by Aspergillus flavus and Aspergillus parasiticus molds. Contamination of feedstuffs with aflatoxins is problematic during the manufacturing, processing, storage, and transportation stages, and it has adverse effects on the health and productivity of poultry and human health. By using inorganic and organic toxin binders in poultry feed, aflatoxins are not allowed to be absorbed through the animal's digestive system, and it is considered a good solution to reduce their negative effects.

In this research, the effects of adding a multi-component toxin binder to diets containing aflatoxin B1 were investigated on growth performance, carcass traits, and immune parameters of broilers, by using 180 one-day-old male broilers (Ross 308) in a 3×3 factorial arrangement in a completely randomized design with three levels of toxin binder (0.0, 0.5, and 1.0 kg/ton) and three levels of aflatoxin B1 (0.0, 0.5, and 1.0 mg/kg) in nine treatments, four replications, and five chickens in each replicate.

The results showed that the using of 1.0 kg/ton of toxin binder significantly reduced the negative effects of 0.5 mg/kg of aflatoxin B1 on the average daily feed intake and weight gain in the finisher and entire production periods and the final live weight in whole production period (P<0.05). The regression equations (Y= -25.033x+ 65.734) with (R2= 0.97), (Y= -23.961x+ 64.844) with (R2= 0.91), and (Y= -15.133x+ 64.319) with (R2= 0.75) were obtained to predict the average daily weight gain of birds fed with treatments containing 0.0, 0.5, and 1.0 kg/ton of "Delta bond®" toxin binder and different levels of aflatoxin B1, respectively. Feeding chickens with diets containing aflatoxin B1 significantly increased liver and spleen weights (P<0.05). All treatments containing 1.0 mg/kg of aflatoxin B1 and treatments containing 0.5 mg/kg of aflatoxin B1 and 0.0 and 0.5 kg/ton of toxin binder showed a significant decrease in the bursa of Fabricius weight compared to the other treatments (P<0.05). In addition, the treatment containing 1.0 mg/kg of aflatoxin B1 without a toxin binder increased heart weight compared to the other treatments (P<0.05). In the case of immune parameters, the amount of heterophils and the ratio of heterophils to lymphocytes were significantly increased and the number of lymphocytes was significantly decreased as the aflatoxin B1 level increased (P<0.05). Furthermore, there were no significant effects for the main and interaction of aflatoxin B1 and the toxin binder for the Newcastle antibody titer.

Based on the results, the addition of 1.0 kg/ton of a multi-component toxin binder to diets containing 0.5 mg/kg aflatoxin B1 can improve the average daily feed intake and weight gain in the finisher and entire production periods, final live weight, and bursa of Fabricius weight of broilers.

During the last stages of incubation, avian mortality commonly happens due to the lack of enough nutrients and amino acids (Fardoost et al. 2019). However, in ovo injection or in ovo feeding is considered a new technique for improving growth of chickens (Ebrahimi et al. 2017). Most studies indicated improving effect of in ovo feeding of nutrients (especially amino acids) on small intestine growth and histology as well as higher absorptive capacity of digestive system (Ebrahimi et al. 2017, 2018a,b; Elwan et al. 2019; Fardoost et al. 2019). Previous studies indicated an improving effect of excess feeding of arginine on growth performance, carcass traits, blood metabolites, and intestinal histology of broilers (Ebrahimi et al. 2013, 2014, 2016b). However, there are few records regarding the impact of in ovo injection of arginine on intestine histology of chickens. Accordingly, the present study was designed to evaluate the effect of in ovo injection of different levels of arginine on carcass traits, blood metabolites, and small intestine histology of broiler chickens.

For this reason, 300 fertile broiler breeder eggs were divided into three treatment groups: 1- 0.5% L-arginine in ovo injection group (100 eggs), 2- 1% L-arginine in ovo injection group (100 eggs), 3- control group included distilled water injected (sham-control subgroup, 50 eggs) and non-injected (control subgroup, 50 eggs). Eggs were then set into the incubator for the first 18 days with the temperature of 37.8°C and six rotations per day. At d 14 of incubation, eggs were injected into the amniotic fluid (Ebrahimi et al. 2017) as follows: 1- in ovo injection of 5 mg L-arginine/ ml distilled water, 2- in ovo injection of 10 mg of L-arginine/ml distilled water, 3- control group included sham-control (in ovo injection of 1 ml distilled water) and control (received no injection). For in ovo injection, solution pH was set at 7.0. At d 18 of incubation, eggs were moved into hatchery boxes. After hatching, chicks were reared for 24 days. During the experiment, chicks received standard commercial diets based on Ross recommendations as starter (0-10 days) and grower (11-24 days), (Table 1). At d 24, blood samples of three chickens per each replicate were collected, centrifuged (3000 rpm for 20 minutes), and serum was separated to evaluate cholesterol, glucose, triglyceride, uric acid, and total protein by the Enzymatic Colorimetric method (Ebrahimi et al. 2017). Then, all birds were weighed, slaughtered, some carcass traits (scalped carcass, eviscerated carcass, breast, thigh, gizzard, proventriculus, pancreas liver without gall bladder, heart, duodenum , jejunum, and ileum were weighed, and their relative weight to chicken body weight were calculated. Also, length of duodenum , jejunum, and ileum was evaluated and their samples were stored in 10% formalin for fixation to evaluate histological parameters (crypt depth, villus height, villus thickness, mucosal thickness, and crypt diameter) using Hematoxylin - Eosin staining method (Ebrahimi et al. 2017). Then, villus height to crypt depth ratios were calculated. Afterwards, data were analyzed based on a completely randomized design by the Proc GLM of SAS software (Ver 9.2). Also, Tukey-Kramer test was used for comparing treatments and results presented as least square means ± standard error.

Based on the results, in ovo injection of different levels of L-arginine did not affect hatchability, day-old chick weight, chick weight to egg weight ratio, 24-day-old chicken weight, feed conversion ratio, relative weight of all carcass traits, cholesterol, glucose, total protein and blood urea nitrogen (P> 0.05), (Table 2). However, serum triglyceride was significantly affected by experimental treatments (P <0.01) and the highest amount was observed in 0.5% L-arginine in ovo injection group (Table 2). In a similar study, Gao et al. (2017) indicated that L- arginine in ovo injection increased weight gain of broiler chickens. Furthermore, Abdolalizadeh Alvanegh et al. (2017) reported the improving effect of in ovo injection of different ratios of L- arginine to L- lysine on chick weight and their carcass traits. Also, they reported higher serum total protein level, while lower blood urea nitrogen of broiler chicks with in ovo injection of different ratios of L- arginine to L- lysine (Abdolalizadeh Alvanegh et al., 2017).Present results indicated no significant effect of in ovo injection of L-arginine on most weight and length parameters of small intestine length (P>0.05); however, relative weight of jejunum was significantly affected by in ovo injection of L-arginine (P<0.05) and the highest amount was observed in 0.5% L-arginine in ovo injection group (Table 3). Present results indicated no significant effect of in ovo injection of L-arginine on duodenal crypt diameter; jejunal villus height, crypt depth and diameter, and mucosal thickness; and ileum villus height, crypt depth, villus height/crypt depth ratio, and mucosal thickness (P>0.05), (Table 3). However, significant effect of in ovo injection of L-arginine was observed on duodenal villus height, villus thickness, crypt depth, villus height/crypt depth ratio, and mucosal thickness; jejunal villus thickness and villus height/crypt depth ratio; and ilium villus thickness and crypt diameter (P<0.05), (Table 3). Also, the highest amount in most histological parameters was observed in 1% arginine treatment (Table 3). In a similar study, it was reported that in ovo injection of L- methionine had a positive impact on small intestine length and weight with improvement in villus height, crypt diameter, crypt depth, and villus height/crypt depth ratio of duodenum and jejunum (Fardoost et al. 2019). Also, in ovo injections of L- lysine improved histological parameters of duodenum, jejunum, and ileum (Ebrahimi et al. 2017). Ebrahimi et al. (2018b) with in ovo injection of different DL- methionine to L- lysine ratios reported higher small intestinal weight and length along with higher Villus height and Villus height to crypt depth ratio.

Based on the overall results of the study, injection of 0.5% arginine showed a positive effect on the growth and small intestine morphology of broiler chickens.

Due to the climatic conditions and the altitude above the sea level, the northern areas of the Alborz mountain range, from Talash forests to Gorgan forests, which are home to several species of oak trees; The use of oak tree fruit due to its nutritious compounds and relying on the appropriate processing method to reduce anti-nutritional compounds and increase its digestibility, has the potential to be investigated in the discussion of feeding livestock. Therefore, the aim of this study was to investigate the effect of different levels of oak fruit processed with sodium hydroxide and urea on performance, apparent digestibility of nutrients, quantitative and qualitative traits of the carcass and some blood parameters of Zell fattening male lambs.

To perform this study, 20 fattening Zell and Atabai mixed lambs with an mean age of 5.5±0.38 months and an initial weight of 27±0.4 kg were used in a completely random design for 90 days. The experimental treatments included the control group (without oak fruit + polyethylene glycol) and treatments containing levels of 10, 20 and 40% in the dry matter of oak fruit processed with sodium hydroxide and urea. The feed consumed by the lambs was in the form total mixed ration at the level of appetite on two occasions (at 8:00 and 17:00). The oak fruit (Quercus castaneifolia) used in this research was collected in the late summer and early autumn from oak trees of the Bolandmazo species, Mazandaran province, Sari city. Experimental animals were weighed every 14 days with 12 hours of feed deprivation. To measure the quantitative and qualitative traits of the carcass at the end of the 90th day of the experiment and after 24 hours of the last feed weighing, 3 lambs were selected from each treatment and killed after 12 hours of feed deprivation. To determine blood parameters at the end of the experiment, 3 to 4 hours after feeding, blood was taken from the jugular vein of the lambs using vacuum tubes containing anticoagulant.

The results of the growth performance showed that the treatment of 40% of processed oak fruit significantly had the highest amount of dry matter intke, daily weight gain, final weight and also the lowest feed conversion ratio (P<0.05). The results of apparent digestibility of nutrients showed that there was a significant difference between experimental treatments in crude protein and NDF (P<0.05). The highest apparent digestibility of crude protein and NDF was observed in the treatment of 20% and 40% of processed oak fruit, respectively. The results of some blood parameters showed that there was a significant difference in the concentration of blood glucose and urea nitrogen between the experimental treatments (P<0.05). The highest concentration of blood serum glucose was observed in the treatment of 40% processed oak fruit. In blood urea nitrogen concentration, the control group had the highest concentration and the 40% processed oak fruit treatment had the lowest concentration. In quantitative and qualitative characteristics of the carcass, the highest slaughter weight, hot carcass weight, cold carcass weight, Leg and Shoulder percentage were found in the treatment of 40% processed oak fruit and the highest carcass yield was found in the treatment of 20% processed oak fruit (P<0.05).

The general results of the present study showed that the fattening end weight, daily weight gain, dry matter intake, lowest feed conversion ratio, as well as valuable parts of the carcass in fattening lambs were improved by consuming 40% processed oak fruit treatment. Apparent digestibility of raw protein and NDF was improved by using 20% and 40% levels of processed oak fruit, respectively.

Profitability of sheep in terms of meat production largely depends on growth traits and carcass characteristics. Despite the importance of the quality of sheep meat, few researches have been conducted in this field in the native sheep of the country. Therefore, the importance of examining the characteristics of animal carcasses, especially when they are still alive, is evident. The aim of the present study was to investigate the genetic and phenotypic relationship between biometric traits, body weights and carcass traits measured by ultrasound in Kurdi sheep of North Khorasan. Since the measurement of carcass traits is difficult and expensive, and in order to better design breeding programs to improve carcass traits, if there is a strong genetic relationship, it is possible to replace traits that are easier to measure with carcass traits that are difficult to measure.

The data of 658 Kurdi sheep in the Shirvan Kurdish sheep breeding and breeding station located in North Khorasan province in the northern area of eastern Iran between 57 degrees east longitude and 37.4 degrees north latitude in the spring, summer and autumn seasons of 2021 were used. The information related to pedigree and birth weights (658 records), three months (652 records), six months (638 records) and nine months (419 records) were extracted from the records recorded in the said station. General linear models (GLM) procedure of SAS software was used to investigate fixed effects on traits. To estimate the parameters and the genetic relationship between the mentioned traits, the restricted maximum likelihood (REML) method was used based on single and two traits animal models in WOMBAT software. Multivariate regression was used to obtain the prediction equation of carcass traits based on other studied traits.

Heritability of subcutaneous fat thickness, area, width and depth of ultrasound longissimus muscle were estimated as 0.1±0.06, 0.06±0.06, 0.10±0.03 and 0.08±0.03 respectively. A high positive genetic correlation was observed between subcutaneous fat thickness and longissimus muscle area (0.71±0.31). Ultrasound carcass traits had a high positive genetic correlation with tail traits. A high positive genetic genetic correlation was found between ultrasound carcass traits and height of the withers, height at rump, heart girth, belly circumference, body diagonal length, thigh circumference and rump depth. The model related to longissimus muscle area with the highest coefficient of determination (0.82) is more reliable than other models for prediction.

The low heritability of traits measured by ultrasound technology in Kurdi sheep of Shirvan Kurdi sheep breeding station showed that improving these traits through individual selection is not very effective and other selection methods (family selection or marker-assisted selection) should be used for improvement of these traits. Generally, due to relatively high coefficient of determination, regression models can be used to predict carcass traits in the flock of Shirvan Kurdi sheep station.

In this experiment, the effect organic forms of zinc, copper, manganese and iron on growth performance, morphology and microbial population of small intestinal using 360 one-day-old Ross 308 male broilers in a Completely randomized design with 6 groups and 6 replicates from 1 to 42 days of age under heat stress conditions. The experimental groups were: 1- basal diet (control), 2- basal diet + 5mg copper-methionine, 20mg manganese-methionine and 5mg iron-methionine (CuMnFe) 3-basal diet + 40mg zinc-methionine, 20mg manganese-methionine, 5 mg iron-methionine (ZnMnFe) 4-basal diet + 40mg zinc-methionine, 5mg copper-methionine, 5mg iron- Methionine (ZnCuFe) 5-basal diet +40mg zinc-methionin, 5mg copper-methionine, 20mg manganese-methionine (ZnCuMn) and 6-basal diet +40mg zinc-methionine, 5mg copper-methionine, 20mg manganese-methionine and 5mg iron-methionine (ZnCuMnFe). The consumption of CuMnFe and ZnCuMn groups increased the villus height as compared to other groups. The birds of all groups had the lower abdominal fat weight, higher muscle layer thickness and lower coliform population in ileum compared to control birds. The number of Lactobacillus bacteria in ZnMnFe and ZnCuMn birds was higher than that of the birds in other groups. In conclusion, consumption of ZnCuFe group in broiler diet under heat stress condition causes the decreased harmful microbial population in intestine and improved performance and breast and thigh weights.

This study was performed to evaluate of effect corn and wheat gluten individually and combination on performance and carcass traits broiler chickens. The experiment was performed using 400 broilers Ross 308 with the same initial weight in a completely randomized design with 4 treatments and 5 replications of 20 pieces for mixed sex and in a period of 42 days. The treatments included: 1- Control. 2- Corn gluten (5 %). 3- wheat gluten (4 %). 4- Mixed corn gluten (2/5 %) + wheat gluten (2 %).The measured experimental characteristics were; feed intake, weight gain, feed conversion and production index. At the end of experimental period one bird was selected randomly from each replicate and slaughtered and carcass characteristics were measured. Results from compare means by duncan test showed that wheat gluten treatment significantly better performance in terms of feed intake, feed conversion ratio and production index is compared to other treatments. But in the case of weight gain, there is no significant difference between treatments. Wheat gluten treatment had a better carcass characteristics in terms of percentages of carcass, breast, thighs, wings and parts of the digestive system is compare to other treatments.

Organic acids are compounds that can be considered as a replacement for antibiotics. Butyric acid is known as the main stimulant of intestinal wall tissue and modulator of normal intestinal microflora (Van Immerseel et al. 2004). Butyric acid is also the main source of energy for intestinal cells and is essential for the development of gastrointestinal-related lymphoid tissue (Friedman and Bar-shira, 2005). The positive and beneficial effect of butyric acid on the functional traits of broilers has been reported (Leeson et al. 2005; Antongiovanni et al. 2007). Butyric acid is a highly volatile and highly smelling compound, much of which is absorbed at the beginning of the gastrointestinal tract (Bolton and Dewar, 1965). The effects of butyric acid appear to improve if it is protected from absorption in the upper gastrointestinal tract (Leeson et al. 2005). For this purpose, butyric acid glyceride along with butyrate-calcium was used in this study. Calcium butyrate is a protected form of butyric acid that is produced using a new technology by Kimia Daroo Mehr Company in Tehran, Iran. This product passes intact through the gut and after decomposition by the pancreatic lipase is absorbed in all different parts of the intestine. Calcium butyrate is a bio-odorless substance and contains 70% butyric acid. butyric acid glyceride (C4) is the brand name of butyroglycerol (Sanadam Pars, Tehran, Iran). Butyric acid is esterified with a glycerol molecule and the resulting compound has a very stable structure. After consumption by animal, pancreatic lipase, it is broken down to the constituents and is absorbed. The aim of this experiment was to investigate the effects of different dietary supplementation levels of calcium butyrate, butyric acid glyceride and their mix on growth performance, carcass traits and jejunal morphology in broiler chickens. A total of 400 one-d-old broilers from Ross 308 strain were allotted to 10 dietary treatments, 5 replicates and 10 broiler chicks per each, from 1 to 42 days of age. Experimental diets included: control (without additives), and supplementation of calcium butyrate (0.15, 0.30 and 0.45% of diet), butyric acid glyceride (C4) powder (0.15, 0.30 and 0.45% of diet), and three levels of calcium butyrate and C4 powder mixture in equal proportion (0.075+0.075, 0.15+0.15, and 0.225+0.225% of diet). Light was provided as 23 h light and 3 h darkness. Rearing house temperature was set at 32°C on day one, and then decreased by 3°C per weak to reach 21±2 °C and remained constant until the end of the experiment. During the experimental period, feed and water were provided ad libitum. Mortality were collected, weighed and recorded daily. At the end of each period, the amount of feed consumed and the group weight of the chickens in each pen were recorded and feed conversion ratio was calculated after adjusting for dead birds. In order to evaluate the morphology of the small intestine at the age of 24 days, one chick per pen close to average pen weight was selected and slaughtered. About one centimeter was removed from the middle part of the jejunm tissue and placed in 10% formalin solution and sent to the laboratory. At the end of the rearing period (42 days), after weighing the chickens, one chick was selected from each replication and slaughtered to measure carcass traits. Data were analyzed in a completely randomized design using General Linear Model procedure by SAS (2009) statistical software. The treatments mean was compared using Duncan's multiple range test at P < 5 %. The average body weight of chicks at the age of 10 days and the mean daily weight gain of 1-10 days in the groups receiving the mixed powder C4 and calcium butyrate (0.225+0.225% of diet) was significantly higher than the control group (P< 0.05). However, the effect of experimental treatments on body weight at 24,42 days of age, and the weight gain at 11-24, 25-4, and 42-1 days of age was not significant (P> 0.05). The feed conversion ratio (FCR) at the age of 1-10 and 1-42 days in control treatment was significantly higher than other treatments (P <0.05). Treatment with mixed powder c4 and calcium butyrate (0.225+0.225% of diet) had the highest relative hepatic weight and lowest abdominal fat weight compared to other treatments (P<0.05). Regarding to the morphological traits of the small intestine, the highest thickness of the muscle layer was observed in the control treatment (P<0.05). Iincreasing villus length can be attributed to the reduction of pathogenic bacteria. Increasing the length of villus increases the digestibility and absorption capacity of nutrients, and since this increase in jujumen, which is the main source of digestion and absorption of nutrients in birds, can be concluded that it is likely the use of organic acids can have beneficial effects on the digestion and absorption of food and subsequently the performance of the birds. In this study the thickness of the muscle layer in the treatment of organic acid intake was reduced, it can be concluded that the use of organic acid supplementation with the effects on the pH gastrointestinal tract probably reduced the pathogenic bacteria in the intestine. By reducing the number of pathogenic bacteria in the intestine and making it healthier, it requires a thinner epithelium to protect the surface of the intestine, which is likely to result in a thickening of the muscle layer thinner. Given that most of the additives that have been introduced as growth promoters have been shown to have an impact on the performance of broiler chickens due to antimicrobial activity and the effect on the microbial flora of the digestive tract. Therefore, breeding conditions and the rate of infection of birds with pathogenic bacteria in the test can be as a result of the test. Each of these additives has different levels of compounds and levels, the dosage and the ingredients used in the experiment can also be effective in the various results obtained from using these growth stimulating agents. In general, the results of this experiment showed that the addition of butyrate-calcium and glyceryl butyric acid to the diet alone or combined with each other, with a positive effect on digestion and absorption of nutrients, could improve the growth performance, some carcasses components and Morphology of small intestine of broiler chicks. The difference in the results of the research may be related to the different buffering capacity of the experimental diets or the type and amount of organic acids used in the experiments.

Phytogenic products have been used as food spices and traditional remedies has a long history in different worldwide nations, but their application in poultry feed industry is almost new. Phytogenic feed additives are natural products originated from different parts of the plants, mostly in the form of powder or extracts. Researches with phytogenic agents have shown various characteristics such as anti-oxidative and antimicrobial effects, regulation of the gut function, and growth promoting effects for this products. They also have been noticed as potential alternatives for antibiotic growth promoters especially after the ban on antibiotic growth promoters in animal feed industry by European Union due to concerns about their residues in animal tissues and subsequent induction of bacterial resistance. It has been shown that the dietary incorporation of herbs and their associated essential oils may provide beneficial effects on poultry performance and health due to the antimicrobial activity of their phytochemical components Turmeric (Curcuma longa) is a member of Zingiberacae family and contains curcumin and its different derivatives as active constituents. Antioxidant, anti-inflammatory and nematocidal activities of turmeric and their relative constituents have been demonstrated in numerous researches. However, the benefits of an additive in animal nutrition matters little if it fails to show a significant economic improvement. Therefore, the objective of the present study was to assess the effects of addition of different levels of turmeric to diet on the growth performance and some economic indicators of broilers production.

To investigate the effect of turmeric addition in diet on growth performance, carcass traits and economic parameters of broilers, a completely randomized design was conducted. Three experimental diets having 0% (control), 0.25% and 0.5% Turmeric were fed to 120 mixed sex of Ross 308 day-old chicks. Chickens were randomly distributed into 12 pens, so as to have 4 replicate per treatment and 10 chicks per pen. The experiment lasted for 42 days. Average body weight gain, feed intake, feed conversion ratio, breast muscle and thigh muscle relative weights and economic indexes were used as a criteria of response. Relative weight of internal organs including heart, liver, gizzard, spleen and bursa of fabricius and abdominal fat were also recorded. Diets were formulated to meet nutrient requirements of chicks according to the Ross 308 Management Guideline (2009) in three periods of starter (0-10 days), grower (11-24 days) and finisher (25-42 days). Feed and water were provided ad libitum. All chicks were vaccinated against Newcastle, Bronchitis and Inflammatory bowel disease, according to the regional vaccination program routine. Body weight and feed intake of chickens were recorded on days 1, 10, 24, 28, 35 and 42 of experimental period and the feed conversion ratio calculated for days 10, 24, 42 and feed cost of each pen, feed cost to weight gain ratio, production efficiency and monetary return calculated for days 28, 35 and 42. At the end of experimental period, 1 chicken per pen was slaughtered, and carcass cuts including breast muscle, thighs, and back bone, neck and wings were weighed in fresh and empty carcass was calculated as sum of these parts. Abdominal fat, heart, liver, spleen and bursa of fabricius were separated and weighed and percent of each part per live weight was calculated. The data were analyzed as a completely randomized design by analysis of variance (ANOVA), using the general linear model (GLM) procedure of SAS (2001). Means were compared using Duncan's Multiple Range Test with accepted level of significance of 0.05.

The results of this experiment showed that, addition of turmeric powder in broiler diet has no significant effect on feed intake, average weight gain or feed conversion ratio. Carcass traits including percentage of breast muscle weight (21.66, 22.78 and 21.62 % respectively in control, 0.25% turmeric and 0.50% turmeric groups), thighs muscle weight (19.98, 19.31 and 20.01% in control, 0.25% turmeric and 0.50% turmeric groups, respectively) and empty carcass weight (58.62, 59.16 and 59.43% in control, 0.25% turmeric and 0.50% turmeric groups respectively) relative to live weight also were not significantly affected by addition of turmeric powder in diet, however abdominal fat was significantly decreased in both turmeric containing treatments (2.98 and 2.90 respectively in treatments containing 0.25 and 0.50 percent turmeric powder vs. 3.31 percent in control group, p<0.05). This may indicate an improvement in fat metabolism of chickens and can be important in terms of human health. Relative weights of internal organs (heart, spleen, liver and bursa) were not significantly different among experimental treatments (p<0.05). Our findings also revealed a significant reduction of production efficiency in 0-28 days period (242.90 vs. 262.90) and monetary return (25452.25 vs. 29445.00) compared to control group as a result of 0.25% turmeric powder addition to feed (p<0.05). Addition of 0.50% turmeric powder didn't affect production efficiency and monetary return, however resulted statistically insignificant increase in feed cost compared to control group (66908.75 vs. 64535.00 rials/kg of weight gain).

Based on results of this experiment, it can be concluded that, addition of turmeric powder in levels used in this experiment (0.25% and 0.50% of feed dry matter) had no beneficial effect on feed intake, growth performance or most of carcass traits. However, the reduction of abdominal fat in turmeric containing treatments was noticeable, usage of turmeric powder as broilers feed additive cannot be recommended in commercial farms because of its negative effects on economic parameters of boilers production. More experiments with different levels of turmeric or in challenging environment may be needed to illuminate beneficial effects of turmeric in broiler feed.

There are different methods to formulate poultry diets, which is one of the newest methods, based on digestible amino acids. Meals are used to provide protein and amino acids in diets. The use of soybean meal has many limitations compared to canola meal. The use of multi-enzyme was done to reduce the limitation in flour such as canola. This experiment was conducted to evaluate the effects of diets formulated based on total and digestible amino acids, soybean and canola meals with or without adding multienzyme on the performance and carcass traits of broilers.

Experiment was conducted as 2×2×2 factorial arrangement with 800 day old of Ross-308 broilers with 8 treatments, 4 replicates and 25 chicks in each,  in a complected randomized design in 3 experimental periods (starter 1-10 days, grower 11-25 days and finisher 25-42 days).

The final results showed that diets formulated based on digestable amino acids, canola meal and enzyme by reduceing the amount of feed intake, improved chicks performance (p<0.05). Canola meal increased the abdominal fat, gizzard, liver and spleen percentages, however the percentages of breast and thighs increased this results also were abserverd in interaction between canola meal, digestible amino acids and enzyme.

The overall results indicated that in broilers in the prsense of multienzyme, use of canola meal in contrast with soybean meal in diets formulated based on digestible amino acids can improve their performance and carcass traits.

This experiment was performed to investigate the effect of saturated and unsaturated fatty acids calcium salts (omega-3 and omega-9) on fattening performance, carcass traits and some blood biochemical properties of Lori Bakhtiari × Romanov male lambs.

49 male lambs with 29.97± 0.88 kg initial weight were divided into 7 equal groups, randomly. Lambs were fed individually with the following experimental diets: 1) Basal diet without fat powder (control), 2) Basal diet with fish oil calcium salts (2% of diet DM) for 90 days, 3) Basal diet with fish oil calcium salts (2% of diet DM) for 45 days, 4) Basal diet with olive oil calcium salts (2% of diet DM) for 90 days, 5) Basal diet with olive oil calcium salts (2% of diet DM) for 45 days, 6) Basal diet with saturated fat calcium salts (2% of diet DM) for 90 days and 7) Basal diet with saturated fat calcium salts (2% of diet DM) for 45 days. Daily feed intake of lambs was recorded and lambs body weight was measured weekly. At the end of the experiment, blood samples were taken from the jugular veins of the lambs. Then 28 lambs were weighed and slaughtered and were measured the weights of different parts of the lambs carcass.

Totally, feeding with calcium salts of fish oil, olive oil and saturated fats significantly increased daily weight gain and reduced the lambs feed conversion ratio compared to control group (p= 0.04). But had no significant effect on dry matter intake of the Lambs. Feeding with saturated and unsaturated calcium salts had no significant effect on serum glucose, cholesterol and triglyceride concentrations. Serum high density lipoproteins (HDL) were higher among the fat treatments than control treatment, but no significant difference was observed between fat treatments. The level of serum low density lipoproteins (LDL) when using of unsaturated fatty acids for 45 and 90 days was significantly lower than the using of saturated fat and control (p= 0.01). Lambs treated with fat powder had higher carcass yields than the control group. Feeding on fish and olive oil calcium salts reduced abdominal fat and kidneys around fat of lambs (p= 0.03).

Totally, results of this study showed that diet supplementation with fish and olive unsaturated fatty acids calcium salts increases the fattening performance and productivity of lambs.

Crossbreeding of fat-tailed native sheep with well known high performance thin-tailed sheep is currently widely used as a rapid solution to enhance production and reproduction, and reduction of fat-tail of native sheep. Nevertheless, comparison studies about native and crossbred animal performance in different environment is necessary for sheep husbandry industry.

This study was performed in the summer using 20 Lori-Bakhtiari (Lori) and 20 Lori-Bakhtiari×Romanov (F1) (Cross) sheep with an average weight of 31.6±2.5 kg in eight treatment with five-repetition for each in a completely randomized design with 2×2×2 factorial array including breed (Lori and Cross), water (free water and water restriction), and food (free food and food restriction). Unrestricted animals had free access to water and food, while water-restricted animals had free access to water for only one hour a day, and food-restricted animals were fed only with 0.45 to 0.65 percent of their body weight. After six weeks of treatments, lambs slaughtered and carcass traits were measured.

Food restriction has widely affected the measured traits in comparsion to water and breed and significantly reduced rectal temperature, respiratory rate, water intake, final weight, carcass weight, Carcass cuts and internal organ weight, fat-tail, visceral fat, total body fat, testis weight and volume (p≤0.01), while increased the water-to-feed ratio and carcass yield without fat-tail (p≤0.007). Water restriction had lesser effects and caused a significant increase in the difference between the maximum and minimum rectal temperature in each period (p<0.05), and decrease in water consumption (p=0.0001), but had no effect on other functional, physiological, and carcass traits. Crossbreeding also significantly reduced fat-tail and total carcass (p˂0.0001), and increased visceral fat, carcass yield without fat-tail, the proportion of carcass cuts, and testis weight and volume (p≤0.01), but had no effect on other traits.

In general, in normal food conditions (regardless the type of access to water) crossbreed animals performed better than Lori, but there is no differencess between them in severe food restriction. Therefore, it could be concluded that in all conditions F1 generation could make the carcass healthier and reduce the generation interval due to less carcass fat and faster maturation.

In order to study of polymorphism in exon 6 of CTSK gene and its association with carcass traits and blood parameters in Afshari×Booroola Merino sheep, blood samples were collected from 97 lambs of animal husbandry station of Zanjan University. DNA was extracted using phenol-chloroform method and a fragment of 500 bp from CTSK gene was amplified with polymerase chain reaction (PCR). The binding patterns for all animals were determined by single stranded conformation polymorphism (SSCP) and then sequenced. For this gene, two binding patterns of GG and GA were identified with the frequencies of 0.74 and 0.26, respectively. Chi-square test (χ2) showed that this population was not in the Hardy-Weinberg equilibrium. Results showed that genotype of GG was significantly associated with increased of tail weight, muscle thickness and muscle cross-sectional area and decreased of cholesterol and VLDL traits. However the more investigations with larger sample size are necessary in future for usage from this locus in breeding programs based on marker-assisted selection.

Ruminal digesta is the nutrients consumed by the animal prior to slaughter, which is processed almost exclusively by rumination and exposure to the various enzymes and protozoa present in the rumen and a complete, ready-to-digest feed. After being processed, it is possible to re-feed it to ruminant animals. The use of digestive leftovers from slaughtered cattle could be a cheap, nutritious, and accessible alternative to the conventional feed ingredients. Therefore, the purpose of this study was to evaluate the effects of replacing cattle and sheep rumen digesta with alternative feed ingredients on the growth performance, carcass quantitative and qualitative traits, and some blood parameters of Dalagh fattening lambs.

A total of 24 Dalagh fattening male lambs at the age of 4.5 months, with a mean live weight of 27 ± 2.0 kg, were assigned to 6 treatments and four replications in individual cages for 90 days. Experimental treatments consisted of: 1) control, without rumen digesta of cattle and sheep, 2) 15% rumen digesta of cattle, 3) 30% rumen digesta of cattle, 4) 15% rumen digesta of sheep, 5) 30% rumen digesta of sheep, and 6) 15% rumen digesta of cattle, and 15% rumen digesta of sheep.

The results showed that daily gain and FCR were significantly different between treatments at the end of experiment (P <0.05). The highest daily weight gain and final body weight as well as the improving feed conversion ratio were observed in the treatment containing 30% rumen digesta of sheep. The results of body biometric showed that body length was significantly higher in the treatment contaning 30% rumen digesta of sheep, compared to the control (P <0.05). The results of quantitative carcass traits showed that treatment containing 30% rumen digesta of sheep in hot carcass weight, cold carcass weight, and crustacean were significantly higher than the control treatment (P <0.05). The results of some blood parameters of day 90 showed that there was a significant difference in the concentrations of glucose, cholesterol, BUN, and total protein between the experimental treatments (P <0.05). Therefore, in the treatment containing 30% of rumen digesta of sheep, the concentration of desired parameters was higher.

The results of this study showed that the use of rumen dried digesta in the diet of fattening lamb was effective in improving growth performance; especially live weight gain, FCR and carcass traits. Consumption of dried rumen digesta of sheep also had a significant effect on some blood parameters of experimental lambs. Similarly, 30% of rumen digesta of sheep had a better performance than other levels.

This study was conducted to determine the effects of Bitter Orange blossom powder (BOBP) on growth performance, carcass characteristics and some blood parameters in broiler chickens under heat stress condition. A total of 200 one day-old male broiler chicks (Ross 308) randomly were divided into five treatment groups in a completely randomized design with four replicates of 10 birds each. The experimental treatments including control (basal diet), the basal diet with Neomycin (0.2% of v diet) and 3 levels of BOBP (0.5, 1 and 2% of diet). Birds submitted to heat stress (32±2ºC from 10.00 AM to 6.00 PM) from 15 to 42 d of age. Blood samples were taken from 8 birds per treatment at the end of experiment. The results showed that, average mortality was significantly lower (P<0.05) in treatments groups (3.75%) than in the control group (22.5%). The diet supplemented with BOBP had no effects on feed intake and weight gain of chicks during different periods (P>0.05). In the grower phase (11-24 d), the lowest fed conversion ratio (FCR) was obtained in 0.5% BOBP, which were significantly different from 2% treatment (P<0.05). Birds receiving diet supplemented with 1% BOBP revealed significantly (P<0.05) lower blood glucose compared to the control group (211 vs 225.8 mg/dl). LDL level was lower (p < 0.05) in 2% BOBP treatment (57.4 mL/dL) compared to 0.5% (69.6 mg/dl). The feeding of BOBP did not induce any significant effect on the whole carcass, breast, drumstick and internal organs weight of broiler chickens (P<0.05). In conclusion, BOBP may be effective in attenuating heat stress effects due to its illustrated antioxidant effects.

Considering that about 70 to 75 percent (in developed countries about 50-60 percent) of the total production costs related to livestock feed. One of the economical ways of producing is to use waste from agricultural and industrial activities, One of the industrial wastes of corn gluten feed that is used in the feeding of dairy cattle, sheep. A little comparison of performance, Carcass traits and digestibility has done of the same energy and protein feeds in sheep. The aim of this study, was the replacement of Soybean meal with corn gluten feed in the diet of fattening lambs and the investigate effect of it on performance, Carcass traits and digestibility.

This experiment was conducted in a completely randomized design with Four diets (Treatment) containing 0, 33, 66 and 100 percent Corn gluten feed was substituted with soybean meal on fattened lambs. Six lambs were given to each treatment (Repeat) with the age of about three months. Animals were individually located in separate cages for 84 days (15 days adaptation period). The protein and energy content of diets were equal. Dry matter, ash, crude fiber, and crude fat were determined according to AOAC (2000), crude protein was determined by Coldall method (AOAC, 2000), NDF, ADF and by van Sost (1991).

The highest daily feed intake was for lambs fed 100% corn gluten and the lowest daily feed for lambs fed 66% corn gluten (P <0.05). reatments containing 66% corn gluten feed had the highest body weight (P <0.05). In most periods, 66% of corn gluten feed showed the highest weight gain (P <0.05). Feed conversion ratio of lambs receiving 66% corn gluten feed improved in most periods (P <0.05). The digestibility of dry matter, organic matter and protein was 66% higher and significantly different from other treatments (P <0.05). Digestibility of cell wall without hemicellulose (ADF), cell wall (NDF), nonfibrous carbohydrate (NFC) and crude fat digestibility (EE) were not significantly different (P <0.05). There were significant differences among treatments for all carcass composition (P <0.05). The 66% corn gluten level treatment showed the best carcass traits compared to the other treatments. Dry matter, organic matter, crude protein, ash, crude fat, crude fiber, cell wall without hemicellulose and cell wall were 87.96, 82.67, 21.66, 6.33, 3.5, 9.4, 37.55, 12.70.

According to the results mentioned and low-cost corn gluten feed, use of corn gluten feed up to 66% in lambs is recommended.

The effects of increasing levels of L-leucine supplementation on performance, carcass traits, breast meat production and determination of digestibleleucine requirement broilers during the grower period (15 to 30 days) using 240 Ross males broiler chickens in a completely randomized design withsix dietary treatments (five repetitions and eight chicks per repetition) was investigated. Treatments include; a basal diet with 1.53% digestible leucineand five diets containing 1.63, 1.73, 1.83, 1.93, and 2.03% digestible leucine by adding synthetic L-leucine to the basal diet. By increasing the levels ofdigetible Leucin, body wieght gain, carcass and breast muscle percentage were increased, but feed conversion ratio and abominal fat percentage weredecreasd (P<0.05). The response trends to increasing levels of digestible leucine were quadratic for weight gain, feed conversion ratio, the relativeweight of carcass, relative weight of breast muscle and relative weight of abdominal fat ( P<0.05). Due to the better fit of the quadratic model to theresponse criteria, digestible Leucine requirements were estimated at 1.70, 1.72, 1.724, and 1.735% for body weight gain, feed conversion ratio, therelative weight of carcass and breast muscle; respectively. Based on the average of these estimates, the suggested digestible Leucine requirements ofbroilers in the grower period is 1.72%.