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Introduction: Although minerals include a small part of the total cost of poultry feed, they perform special functions in the body. Given that today's birds are primarily raised under stressful conditions (including high production demands, environmental stress, heat, and exposure to various other stress factors), their nutrient metabolism, including the absorption of minerals, has changed. This has led to decreased feed consumption, reduced mineral absorption, and consequently, increased excretion of minerals. Minerals that serve as cofactors for many enzymes are crucial; thus, to support proper functioning and enhance the immune system's response, higher amounts of these nutrients are required in diets. Chromium (Cr) is a critical micronutrient for humans and animals. It contributes to physiological and nutritional efficiency. Chromium increases glucose glycogenesis, promotes glucose transport, and increases protein synthesis. Chromium is important in protein digestion and reduction of lipid peroxidation and increased growth production. Chromium deficiency is associated with reduced growth rate, and glucose, and protein metabolism. Under environmental, nutritional, and hormonal stress, the benefits of chromium supplementation clearly demonstrated. Considering that with the increase in age and egg size, the egg quality decreases, and also the function of the immune system decreases at the late phase of egg production. Therefore, supplementation of layer hen diets with some nutrients at the end of the production period can improve the egg quality and potentiate the humoral immune response. Thus, the subject of the current study was to investigate the effects of dietary supplementation of chromium-methionine on egg laying performance, egg quality traits at different storage times and temperatures, humoral immune response, and some blood biochemical parameters of laying hens at late–phase of the egg production cycle.Materials and Methods: A total of 120 Leghorn laying hens (Hy-line W36, 73 weeks- old) were assigned in a completely randomized design with 6 dietary treatments, 5 replicates and 4 laying hens in each replicate for 6 weeks. The experimental treatments were 6 levels of chromium-methionine supplementation (0, 400, 800, 1200, 1600, and 2000 μg/kg of diet) of corn-soybean meal-based diet. The hens were housed in a 60 × 60 × 40 cm cage. All hens were housed in an environmentally controlled house with temperature maintained at approximately 25ºC. The house had controlled ventilation and lighting (16L: 8D). All hens were supplied with feed and water ad libitum. The hen-day egg production, egg weight, egg mass, feed intake, and feed conversion ratio were recorded daily. The feed conversion ratio was expressed in kilograms of feed consumed per kilogram of the egg mass. The effects of organic chromium supplementation of laying hens on egg quality traits were evaluated every 2 weeks at 75, 77, and 79 weeks of age. The egg shape index was calculated by dividing egg length to egg width. At the end of the experiment, to measure certain blood parameters, one bird from each replicate was selected, and blood was drawn from the wing vein. After preparing the serum, the concentrations of triglycerides, cholesterol, total protein, albumin, globulin, uric acid, alanine transaminase, aspartate transaminase, glucose, and malondialdehyde were measured using Pars Azmoon kits according to the manufacturer's instructions.Results and Discussion: Supplementing the diet with chromium-methionine had a significant effect on laying performance (including feed intake, feed conversion ratio, and egg production) and egg quality traits (such as eggshell weight, yolk color, yolk weight, albumen height, and Haugh unit). The results showed that birds fed 2000 µg/kg chromium-methionine had the lowest feed intake and the best feed conversion ratio and egg production percentage were observed with the addition of 1600 and 2000 g/kg organic chromium. By suppressing stress factors, chromium can increase the ovulation rate and increase the percentage of egg production. Addition of organic chromium except 2000 μg/kg improved albumen height and Haugh unit compared to the control group. The interaction effect between egg storage time and storage temperature on the yolk height and yolk percentage, albumen and yolk pH were significant. Carotenoids are responsible for the color of the yolk and they are a part of the fat-soluble compounds, so any factor that can improve the digestion and absorption of fats will probably lead to an increase in the color of the egg yolk. Haugh unit is a measure to determine the quality of egg white, which determines the quality of the egg. The higher HU means better egg quality (fresher, higher quality eggs have thicker whites). Blood serum cholesterol of chickens fed with 800 µg/kg of chromium-methionine decreased compared to the control group. The lowest serum concentration of malondialdehyde was observed using 1600 and 2000 µg/kg organic chromium. Addition of 1600 µg/kg of chromium-methionine increased total immunoglobulin production against sheep red blood cells. The effects of dietary chromium supplementation on improving immune responses can be attributed to its antioxidant activity. By enhancing antioxidant activity, chromium reduces the production of corticosterone, a potent suppressor of immune system function. This reduction in corticosterone levels prevents the decrease in lymphocyte production and proliferation, ultimately supporting the continued production of antibodies.Conclusion: In total, dietary supplementation of 1600 μg/kg chromium-methionine can improve egg laying performance including feed conversion ratio, egg production, and egg mass, as well as egg quality traits such as egg shell weight and albumen height of laying hens at the late-phase of laying cycle. Supplementation of layer diets with 1600 μg/kg organic chromium improved the humoral immune response at the late-phase of egg production cycle by increasing the production of total immunoglobulin against sheep red blood cells.

Background Restaurant waste (RW) can be considered as a valuable feedstuff for animal nutrition due to its high nutritional value and low price. The aim of this study was to determine nutritional value and the microbial load of the waste in order to incorporate it in the poultry feedstuff. To our knowledge the current study is the first attempt in the field of RW processing with Lactobacillus strains. Then the second goal of this experiment was to study the effect of RW processing with Lactobacillus on nutrient and chemical composition of RW. The four Lactobacillus strains applied in the study included Lactobacillus casei subsp1608 ATCC 39392, Lactobacillus plantarum-1058 ATCC 8014, Lactobacillus acidophilus-1643 DSM 20079 and Lactobacillus reuteri-1655 DSM 20016. Results The experiments in the case of chemical composition showed that the mixed processing caused a significant improvement in nutritional value compared to the raw waste (P.05). Among the strains, L. acidophilus had the highest mean amount of crude protein (CP), ether extract (EE), dry matter and gross energy (GE) with 21.40, 19.91, 41.02 and 4,872.61 kcal/kg, respectively, and the lowest amount of ash (3.67 %) compared with other strains. In the second phase of the experiment, the results obtained from comparing the average total count of bacteria and coliforms in five types of RW proved that the means of both bacteria and coliforms are within the standard range and can be applied as poultry feed. However, regarding the average total count of bacteria, barbecue waste with 9.85 9 104 CFU/g and chicken waste with 9.51 9 103 CFU/g were the most contaminated and the healthiest foods, respectively. In addition, barbecue waste with 1.28 9 102 CFU/g and fish waste with 1.08 9 102 CFU/g had the highest and lowest count of coliforms, respectively. Conclusion Nutritional value determination of RW samples showed that it is in the level that can be used in poultry diet. It was also presented that by adding Lactobacillus strains to the waste, the amount of GE, CP and EE increased and ash amount decreased. Therefore, its use in poultry diet is highly economic. In addition, this study showed that RW microbial load is in the level that can be applied as poultry feedstuff.

Introduction: Vitamin D3 is one of the important vitamins in calcium metabolism, which increases the active transport of calcium and phosphorus in the intestinal epithelium. However, the mechanism by which vitamin D3 increases the absorption of calcium and phosphorus is not fully understood. The active form of vitamin D3 or 1,25-hydroxycalciferol is transported to the nucleus of the intestinal cells. In the presence of 1, 25-hydroxycalciferol, a specific RNA is secreted from the cell nucleus, which is translated into a specific protein by the ribosomes, thereby increasing the uptake of calcium and phosphorus. The primary role of 1, 25-hydroxyvitamin D3 in vertebrates in regulating calcium homeostasis is the direct action of 1,25-hydroxyvitamin D3 on the gut, kidneys and bones by inhibiting the production of parathyroid hormone in the parathyroid glades. Vitamin C prevents stress by preventing the release of corticosteroid hormones, which can be effective for bird function, egg production and reducing mortality. In the liver, vitamin D3 is converted into 25-hydroxycalciferol, which is later converted into calciferol hydroxylase (activated by vitamin C) in the kidneys by the enzyme 25-hydroxy molecule. This metabolite increases the absorption of calcium and phosphorus from the intestinal wall and renal tubules. The aim of this experiment is therefore the effect of vitamin D3 and vitamin C on performance, egg quality and hatchability in broilers breeder hen at the end of the production period. Materials and Methods: A total of 240 broiler breeder hens and 24 cockers (Ross 308) were distributed in a 2×2 factorial arrangement including two levels of vitamin D (3500 & 5500 IU) and two levels of vitamin C (0 & 150 mg/kg) with 6 replicate pens of 10 hens and one cock each. The experiment lasted for 12 weeks (from the age of 49 to 61 weeks), and during the trial, the performance traits production and hatchability were recorded. Every 28 days 4 eggs were evaluated for internal and external quality. Results and Discussion: The results of the study showed that the main effect of vitamin D3 had a significant impact on egg weight, with higher concentrations resulting in a reduction in egg weight. However, there was no significant effect on other performance parameters. The main effect of higher concentrations of vitamin D3 was an increase in the number of hatching eggs, shell percentage, shell thickness, specific gravity of the eggs, a decrease in the percentage of egg breakage. However, this effect was not significant for other parameters. Increasing the level of 1,25 hydroxycalciferol significantly increased plasma calcium levels, which led to increased renal 1-alpha-hydroxylase activity, envelope secretion, reduced oocyte rupture, resulting in increased hatch fertility. The main effect of vitamin C significantly increased production percentage and reduced feed conversion and feed consumption per egg. However, there was no significant effect on other parameters. Addition of vitamin C significantly increased external characteristics of the eggs, including shell proportion, shell thickness, shell ash and phosphorus, number of hatching eggs, but reduced the number of broken eggs. However, there was no significant effect on internal parameters, except for yolk color. The use of vitamin C activates the enzyme 25-hydroxycholecalciferol hydroxylase to produce 1,25 hydroxycalciferol, which increases calcium absorption from the intestinal wall and reduces the number of ruptured eggs. Regarding the interaction of different levels of vitamin D3 and vitamin C, the results showed that higher levels of vitamin D3 and vitamin C increased production percentage, egg mass, number of hatching eggs, shell thickness, phosphorus and FCR. Intake in the egg removed significantly increased, but the number of broken eggs decreased. Conclusion: In general, according to the results of the present experiment, it can be concluded that the use of vitamin C in an amount of 150 mg / kg with 5500 IU of vitamin D3 can increase the production percentage, increase the mass of eggs and improve the feed conversion ratio. It can also increase shell thickness and the number of chickens produced weekly and over the period, decrease the number of broken eggs, increase the number of hatching eggs, reduce feed intake per egg and feed intake per chicken at the end of the broiler breeder production period.

This study aimed to investigate the interactions between corn particle size (PS) and conditioning temperature (CT) on the performance, carcass traits, intestinal morphology, and immune responses in broilers fed a corn-soybean meal-based diet. A total of 360 one-day-old male broiler chicks (Ross 308) were randomly allocated into six dietary treatments in a 2 × 3 factorial arrangement, consisting of two corn PS (finely ground with geometric mean diameter (GMD) of 357 µm (PSF) vs. coarsely ground corn with GMD of 737 µm (PSC), and three CT [unconditioned (CTU), conditioned at 75 °C (CT75) and 90 °C (CT90)]. Birds were accommodated in 30 pens with five replicates and 12 chicks per each pen. There was no interaction between corn PS and CT on the growth performance and immune response of broilers at any growth phases. However, during the starter (0–10 days) period, the average daily weight gain (ADWG) and feed conversion ratio (FCR) of PSF-fed birds were significantly improved compared to those fed PSC (p < 0.05). During the starter (0–10 days) and grower (11–24 days) periods, increasing the conditioning temperature of corn increased the ADWG, while in the starter phase only the CT75 caused a lower FCR (p < 0.05). Broilers fed PSF corn showed the lowest FCR during the finisher (25–42 days) period compared to those fed PSC (p < 0.05). Conditioning corn at 75 °C reduced FCR during the finisher (25–42 days) period compared to the birds fed CTU and CT90 corn (p < 0.05). In whole experimental periods (1–42 days), PSF and CT75 treatment increased the ADWG compared to the PSC and CTU (p < 0.05). The CT75 treatment improved primary total anti-sheep red blood cell (SRBCs) titer (IgT) and IgM and secondary IgT and IgG responses compared to the other experimental groups (CTU and CT90) (p < 0.05). No significant PS × CT interaction was found on the Newcastle disease (ND) antibody titer of broiler chickens (p > 0.05). Feeding CT75 corn reduced duodenum and jejunum relative lengths compared to the birds fed diets containing CTU corn. Significant PS × CT interactions (p < 0.05) were observed for villus height, villus height to crypt depth, crypt depth, muscle thickness, and absorption surface area of the jejunum. The highest carcass yield was observed in the PSF-CT75 group (p < 0.05). In conclusion, the use of finely ground corn (PSF) conditioned at 75 °C (CT75) was beneficial to growth performance, development of the digestive tract, jejunum histomorphometry and the immune responses of broilers.

In order to investigate the effects of using different levels of either raw or processed amaranth (Amaranthus hybridus chlorostachys) grain on performance productivity, egg physicochemical properties, blood biochemistry and egg fatty acids, a trial was conducted using 168 Hy-line W-36 laying hens (67 week of age) in a completely randomized design with seven treatments and six replications of four birds for eight weeks. The trial treatments included the control group receiving no amaranth and the test groups receiving 5, 10 and 15% of raw or autoclaved (120 °C for 5 min) amaranth grain based on dry matter. The results showed that the use of processed amaranth up to the level of five and ten percent of the diet compared to raw amaranth resulted in a better performance than the control group (p < 0.05). The consumption of amaranth decreased blood glucose, cholesterol and triglyceride of trial birds without having a negative effect on their health and blood antioxidant status (p < 0.05). The use of different forms of amaranth in diets of laying hens had no negative effects on the physicochemical properties of eggs and led to the production of eggs with reduced yolk cholesterol and triglyceride; however, the omega-6 content in eggs and the ratio of omega-6/omega-3 increased (p < 0.05). In conclusion, the use of amaranth grain at low levels in the diet of laying hens can enhance the health of the bird and the production of quality and useful eggs.

Ruminants are one of the largest anthropogenic methane and nitrous oxide emissions. Therefore, the hypothesis was to study the effects of reducing dietary crude protein (CP) level on environmental contaminators when rumen-protected amino acids and choline chloride were supplemented. Sixty Holstein dairy cows were used during the experiment. Test diets were: (1) CD = Control diet with16.2 g of crude protein/ Kg of DM); (2) LM = Low protein diet with 14.2 g of crude protein/ Kg of DM + methionine ; (3) LL = Low protein diet with 14.2 g of crude protein/ Kg of DM + lysine; (4) LML = Low protein diet with 14.2 g of crude protein/ Kg of DM + methionine + lysine; (5) LMLC = Low protein diet with 14.2 g of crude protein/ Kg of DM + methionine + lysine + choline. Dry matter and NDF intake were not different, but the control group received higher CP and ADF compared with other groups (P < 0.05). Fecal CP and ADF of control group were lower (P < 0.05), but no differences were observed for fecal dry matter (DM) and NDF. Milk yield and protein content were higher for LML and LMLC like control group (P < 0.05). Nitrogen intake, urinary N, urinary urea N and total excreta N decreased (P < 0.05) when animals fed low protein. There was no difference in ruminal pH and acetate to propionate ratio, whereas the ruminal ammonia-N decreased with the low protein (P < 0.05). The 120-h gas production test, showed no difference on the kinetics of digestion and in vitro methane emission. However, the inclusion of DMI in the calculations revealed that low protein can reduce (P < 0.05) methane emission. Overall, our findings indicated that low protein can be compensated for by adding rumen-protected amino acids, not only to maintain the animal performance, but also to decrease nitrogen excretion and methane emission.

A feeding trial was performed to assess the effects of dietary raw amaranth (Amaranthus hybridus chlorostachys) grain (RAG), with or without an enzyme blend, on the productive performance, blood biochemistry, and antioxidant status in laying hens. The trial was conducted following a completely randomized design by factorial method, including five levels of RAG (0, 10, 20, 30, and 40%, respectively) and two levels of enzyme blend (0 −E and 0.025 +E %). A total of 960 White Leghorn (Hy-line W-36) laying hens (56 weeks of age) were divided into 10 groups with eight repetitions, including 12 birds. The trial period was ten weeks. Results showed that RAG levels in feed (>10%) led to a significant decrease in blood total cholesterol (TC), but they also significantly decreased feed conversion ratio (FCR) (p ˂ 0.05) as measured by feed intake (FI), hen daily production (HDP), egg weight (EW), and mass (EM), leading to overall worse productivity compared to the control group. On the contrary, the addition of the enzyme blend led to an improvement in the investigated production traits (p ˂ 0.05), with the exception of HDP. The enzyme blend was also capable of recovering productive performance when combined with low concentrations of RAG (10%) (p ˂ 0.05), and RAG × enzyme blend groups showed the lowest values of TC (p ˂ 0.05). Moreover, the interaction effects for atherogenic index (LDL/HDL) indicated a significant and promising reduction in response to the addition of RAG both in the presence and absence of the enzyme blend (p ˂ 0.05), and this additive also significantly reduced levels of egg yolk cholesterol (p ˂ 0.05). In summary, the evidence gathered in this trial showed that dietary RAG had positive effects on egg quality characteristics, leading to the production of low-cholesterol eggs, and, at the same time, it may improve the health status of laying hens. Furthermore, the addition of an enzyme blend allowed feeding up to 10% RAG in the diet, leading to an optimal balance between animal productivity and the beneficial effects of RAG.

The objective of this study was to investigate the effects of feeding Amaranthus hybridus chlorostachys grain (AG) with (+E) and without enzyme (−E) on performance, egg quality, antioxidant status and lipid profile of blood serum and yolk cholesterol in laying hens. A total of 960 white leghorn (Hy-line W-36) commercial layers (56 weeks) were divided into 10 groups with 8 replicates per group (12 birds per replicate, including 3 adjacent cages with 4 birds each). A completely randomized design was implemented with a 5 × 2 factorial arrangement of treatments consisting of five levels of AG (0, 100, 200, 300 and 400 g/kg) and two levels of multienzyme complex addition (0 −E and 0.25 +E g/kg) fed to the hens for 12 weeks (2 wk. adaptation + 10 wk. main experiment). Feed intake (FI) and percentage of hen day production (HDP) were not affected by main effect of the AG level, but egg mass (EM) and egg weight (EW) were decreased (p < 0.01), and the feed conversion ratio (FCR) was impaired (p < 0.01). EM, EW and FCR were improved by enzyme addition (p < 0.01). EM, EW and FCR were affected (p < 0.01) by the interaction of AG and enzyme addition. The highest value of EM and the lowest value of FCR were observed in hens on the diet containing 200 g/kg AG with enzyme addition. Egg yolk cholesterol content was reduced (p < 0.05) by up to 10% with increasing levels AG in experimental diets. The egg quality traits, including Haugh units of protein quality, strength and shell thickness, were not affected by the main effects or interaction of AG and enzyme consumption. Amaranth feeding led to a decrease (p < 0.05) in triglyceride (TG) and low-density lipoprotein (LDL) while also promoting increases (p < 0.05) in the high-density lipoprotein (HDL) and total antioxidant capacity (TAC) of the blood. A comparison of the effects of contrasts showed that functional parameters (except FI), yolk cholesterol, antioxidant parameters (except MDA) and blood lipid profile had differed significantly (p < 0.05) between the hens fed amaranth versus those not fed amaranth. These findings indicate that feeding a diet containing up to 200 g/kg of AG with enzyme addition can improve EW, EM and FCR. Feeding laying hens diets containing AG also positively influenced blood traits and antioxidant status in laying hens while reducing egg yolk cholesterol content.

Amaranth is a pseudocereal which can thrive in conditions of drought and limited inputs. Samples of amaranth grain were subjected to proximate analysis with standard laboratory methods. We conducted two experiments to determine apparent (corrected to zero nitrogen balance) metabolisable energy (AMEn) content of untreated (UAG) and heat-treated (HTAG) amaranth grain for Ross-308 male broiler chicks (35–42 d and BW 2141 ± 10.41 g). In each experiment, 10 assay diets (ADs) were fed to 400 birds in individual metabolism cages in a 2 × 5 factorial design. ADs were obtained by substituting amaranth for the main ingredients in the reference diet (RD). Two levels of enzyme addition (0 and 0.55 g/kg) and five amaranth replacement rates (0, 150, 300, 450 and 600 g/kg) were used, and metabolism trials were conducted using the total excreta collection method. Two regression equations were estimated for UAG, with and without enzyme addition, that determined the AMEn content of UAG as 3264 and 3255 kcal/kg, respectively. For HTAG, the AMEn contents with and without enzyme addition were 3973 and 3828 kcal/kg, respectively. Thus, enzyme addition improved the energy value of UAG and HTAG by 0.28 and 3.8%, respectively. The AMEn value of HTAG was 708 and 573 kcal/kg higher than UAG in diets with and without enzyme addition, respectively. Thus, we conclude that there was more benefit from heat treatment than enzyme addition, but there was a synergistic effect of heat treatment and enzyme inclusion on the metabolisable energy concentration of amaranth in the diets of broilers.

This study was performed to evaluate the effect of folic acid (FA) on performance, egg quality and yolk 5-methyltetrahydrofolate (5-MTHF) content. A total of 384 Hy-line W36 strain hens from 52 to 58 weeks of age were randomly assigned to 4 groups, and each group received one of following dietary treatments: 0, 5, 10 and 15 mg FA/kg diet. A completely randomized design was used. Egg production percentage, egg mass and egg weight were increased significantly (P

An experiment was carried out to investigate the effect of multi-enzyme in high and low levels of metabolizable energy (13.81 and 11.51 MJ kg-1 diet) on performance and energy utilization of broilers fed wheat-soybean meal diets from 0 to 21 days of age. Result showed that birds fed diets containing 11.51 MJ kg-1 consumed significantly (p < 0.05) more feed than diets containing 13.81 MJ kg-1, whereas daily gain and feed conversion ratio improved (p < 0.05) when enzyme was added to 11.51 MJ kg-1 diet. There was significant improvement in metabolizable energy, net energy for production, organic and dry matter digestibility in 0-21 when diets supplemented with enzyme (p < 0.05). Addition of enzyme to 11.51 MJ kg-1 containing diet significantly (p < 0.05) reduced heat production of birds in 0-10 d, whereas heat production was not changed in 21 days. Supplementation of 11.51 MJ kg-1 diet with enzyme improved the efficiency of ME use for carcass energy and protein retention of broilers (p < 0.05). Generally, the results of current study demonstrated that addition of enzyme to wheat-soybean diets improved NEp of broiler chickens while MEI was not changed and it seems NEp is a more sensitive energy utilization response criterion to use in evaluating broilers response to enzyme supplementation.

The nutritive value of pistachio epicarp (PE) was evaluated by in situ and in vitro techniques. Chemical analysis indicated that PE was high in crude protein (11.30%) and low in neutral detergent fiber (26.20%). Total phenols, total tannins, condensed tannins and hydrolysable tannins contents in PE were 8.29%, 4.48%, 0.49% and 3.79%, respectively. Ruminal dry matter and crude protein degradation after 48 hr incubation were 75.21% and 82.52%, respectively. The gas production volume at 48 hr for PE was 122.47 mL g-1DM. As a whole, adding polyethylene glycol (PEG) to PE increased (p < 0.05) gas production volumes, organic matter digestibility and the metabolizable energy that illustrated inhibitory effect of phenolics on rumen microbial fermentation and the positive influence of PEG on digestion PE. The results showed that PE possessed potentials to being used as feed supplements.

This study was conducted to determine nutritive value of common animal feed sources in East Azerbaijan province including second cutting of alfalfa hay ( N=35) and wheat straw (N=26). Chemical composition and mineral contents of alfalfa hay and wheat straw were determined according to standard methods. Then the average chemical compositions of these samples were compared with those of the Gilan, Kurdistan and Kermanshah samples and the National Research Council (NRC) data. The results demonstrated that the mean dry matter (DM) content of alfalfa hay and wheat straw were 942.4± 5.6 and 948.7 ± 6.5 g/kg, and mean crude protein (CP) concentrations were 158.6 ± 11.4 and 40.7 ± 4.8 g/kg of dry matter, respectively, that showed a significant difference with NRC data. Neutral Detergent Fiber (NDF) content of alfalfa hay was 347.5 ± 51.5 g/kg and Acid Detergent Fiber (ADF) of alfalfa hay and wheat straw were 447.3 ± 39.2 and 703.1 ± 5.55 g/kg, respectively; that showed no significant difference. The content of calcium in the alfalfa hay was 13.9 ± 3.5 g/kg that revealed no significant difference with the NRC data. The calcium concentration of wheat straw was 5.7 ± 1.4 g/kg, that differed significantly with the NRC data. The gross energy of alfalfa hay and wheat straw were 4100±154 and 3981± 126 kcal/ kg, respectively. In conclusion, it is recommended that agricultural managers in regional programming, farmers and feed manufacturers in balanced feed formulation use this data.

Food by-products in Iran are produced in high levels. In this study, in situ and in vitro gas production techniques were used to describe nutritive value of apple pomace, tomato pomace and noodle waste. For this purpose two ruminal fistulated sheep were used. Nylon bags which were approximately (6x12 cm) containing 5 g samples (2 mm screen) were incubated in duplicate in the rumen of fistulated sheep for 0,2,4,6,8,12,16,24,36 and 48 h. The gas production was recorded after 2, 4, 6, 8, 12, 16, 24, 36 and 48 h of incubation and the equation of P = A ([1-e.sup.-ct]) was used to describe the kinetics of gas production. The data was analyzed using completely randomized design. DM and CP disappearance were significantly different among feedstuffs (p Key words: By-product, in situ, gas production, metabolizable energy, INTRODUCTION A major constraint to increasing livestock productivity in developing countries is the scarcity and fluctuating quantity and quality of the year-round supply of conventional feeds. These countries experience serious [...]

Some feedstuffs which used in ruminants diet (corn grain, soybean meal, wheat bran and alfalfa) were analyzed for chemical composition, apparent in vivo nutrient digestibility, in vitro fermentation gas production and metabolizable energy. Chemical composition of test feeds differed in nutrient contents. Initially apparent in vivo digestibility of alfalfa nutrients were obtained then digestibility of nutrients for the other test feeds were determined by difference method, using 16 Ghezel mature rams (mean weight of 43.9[+ or -]4 kg). In vivo DM, CP, NDF and OM apparent digestibility were different among the test feeds (p Key words: Feed evaluation, in vivo digestibility, gas production, metabolizable energy, INTRODUCTION The nutritive value of a ruminant feed is determined by the concentrations of its chemical components, as well as their rate and extent of digestion. Determining the digestibility of [...]