پردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222An Estimation of Discounted Genetic Expressions of Dairy Traits in Iranian Holstein HerdsAn Estimation of Discounted Genetic Expressions of Dairy Traits in Iranian Holstein Herds18919723538FAAliSadeghi SefidmazgiArdeshirNejati-Javaremi0000-0002-0228-011XMohammadMoradi-Shahrbabak0000-0002-5255-609XSeyed RezaMiraei AshtianiPeterR AYMERJournal ArticleThe objective of this study was to assess the Discounted Genetic Expressions (DGEs) for different categories of animal traits as regards Holstein cattle of Iran. Using discounted gene-flow principles, DGEs per calf born were estimated for self replacing females and also for their sires. In the situation for sires of self replacing females, relative GDEs per cow per year for annual cow traits, traits of the calf at birth and slaughter, traits of heifer and traits of cow at culling were estimated as 1, 0.96, 0.4, 0.44 and 0.43, respectively. The respective values for self replacing females were 1, 0.5, 0.21, 0.44 and 0.43, respectively. The effects of different factors on DGEs were quantified using sensitivity analysis. Results obtained in this study provide important information for properly weighting the traits in national selection indexes and as well in conducting cost- benefit analyses of breeding strategies.The objective of this study was to assess the Discounted Genetic Expressions (DGEs) for different categories of animal traits as regards Holstein cattle of Iran. Using discounted gene-flow principles, DGEs per calf born were estimated for self replacing females and also for their sires. In the situation for sires of self replacing females, relative GDEs per cow per year for annual cow traits, traits of the calf at birth and slaughter, traits of heifer and traits of cow at culling were estimated as 1, 0.96, 0.4, 0.44 and 0.43, respectively. The respective values for self replacing females were 1, 0.5, 0.21, 0.44 and 0.43, respectively. The effects of different factors on DGEs were quantified using sensitivity analysis. Results obtained in this study provide important information for properly weighting the traits in national selection indexes and as well in conducting cost- benefit analyses of breeding strategies.https://ijas.ut.ac.ir/article_23538_3914109deb198245a300d2ec7561e405.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222An Association between the C>T Single Nucleotide Polymorphism of Bovine OPN Gene and Milk Production and Composition in Iran Holstein CattleAn Association between the C>T Single Nucleotide Polymorphism of Bovine OPN Gene and Milk Production and Composition in Iran Holstein Cattle19920523539FAMajidPasandidehMohammadrezaMohammad-abadiAlirezaTorangAliEsmaeilizadeh Kashkoueiyejh0000-0003-0986-6639Journal ArticleQuantitative trait loci (QTL) affecting milk production traits on bovine chromosome 6 close to the OPN gene location have been identified through several whole genome scans. OPN is a phosphoprotein, synthesized in a variety of tissues and cells and secreted into body fluids. In this study, DNA was isolated from blood samples collected from 398 Holstein cows in Tehran and Esfahan provinces. DNA isolation was performed using salting out method. RFLP-PCR method was used for genotyping of SNP C>T at position 8514 in OPN gene. Frequencies of CC, CT and TT genotypes were estimated as 19, 57 and 24%, respectively. Hardy-Weinberg Equilibrium (HWE) was evaluated using ? square test. The genotypes in this locus deviated from HWE. In this study, significant associations were observed between c.8514C>T genotypes in OPN gene and FATP2X, PROPER305 traits. The SNP, showing signi?cant association with milk traits would provide an excellent opportunity for marker assisted selection programs in dairy cattle.Quantitative trait loci (QTL) affecting milk production traits on bovine chromosome 6 close to the OPN gene location have been identified through several whole genome scans. OPN is a phosphoprotein, synthesized in a variety of tissues and cells and secreted into body fluids. In this study, DNA was isolated from blood samples collected from 398 Holstein cows in Tehran and Esfahan provinces. DNA isolation was performed using salting out method. RFLP-PCR method was used for genotyping of SNP C>T at position 8514 in OPN gene. Frequencies of CC, CT and TT genotypes were estimated as 19, 57 and 24%, respectively. Hardy-Weinberg Equilibrium (HWE) was evaluated using ? square test. The genotypes in this locus deviated from HWE. In this study, significant associations were observed between c.8514C>T genotypes in OPN gene and FATP2X, PROPER305 traits. The SNP, showing signi?cant association with milk traits would provide an excellent opportunity for marker assisted selection programs in dairy cattle.https://ijas.ut.ac.ir/article_23539_2965658b89b496b7c43d6a6ea3ac930b.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222The Effect of Degradability Rates of Different Starch Sources on Performance and Blood Metabolites of Holstein Dairy Cows in their Early LactationThe Effect of Degradability Rates of Different Starch Sources on Performance and Blood Metabolites of Holstein Dairy Cows in their Early Lactation20721923540FAHamidAmanlou0000-0002-5631-125XBehzadAlizadehMohammad-HosseinShahir0000-0003-2327-1877TaherehAmirabadi FarahaniJournal ArticleIn order to examine the effect of degradability rates of different starch sources on performance of Holstein dairy cows in their early lactation, twenty multiparous lactating Holstein cows (586±33.7 BW; 48.15±9.32 DIM) were made use of in a randomized complete block design of four treatments during the 65 days of the experimental period. Cows were fed the following diets: 1) 100% barley, 2) 67% barley and corn 33%, 3) 33% barley and 67% corn and finally 4) corn by 100%. Cows were offered feed individually and three times daily. Dry Matter Intake (DMI), milk yield and composition, feed efficiency, blood metabolites, ruminal and fecal pH, body weights and body condition scores were assessed. Dry matter intakes (P=0.01), and milk yields (P=0.03) were highest for cows fed diet containing 33% barley and 67% corn. Milk fat percentage (P=0.001), milk non fat solid percentage (P=0.17) and milk lactose content, percentagewise (P=0.2) were lowest for cows fed diet containing 100% barley. Ruminal pH (P=0.09) was lowest in cows fed diet containing 100% barley while highest for cows fed diet containing 100% corn. No significant differences were found in blood BHBA, NEFA, BUN and in total protein. Blood glucose (P=0.018) and albumin were recorded as lowest in cows fed diet containing 100% barley. These results most probably reflect a more optimal synchronization of dietary protein and energy for dairy cows when fed diets containing 33% barley and 67% corn in their early lactating diets rather than alfalfa hey formerly fed as the sole forage source.In order to examine the effect of degradability rates of different starch sources on performance of Holstein dairy cows in their early lactation, twenty multiparous lactating Holstein cows (586±33.7 BW; 48.15±9.32 DIM) were made use of in a randomized complete block design of four treatments during the 65 days of the experimental period. Cows were fed the following diets: 1) 100% barley, 2) 67% barley and corn 33%, 3) 33% barley and 67% corn and finally 4) corn by 100%. Cows were offered feed individually and three times daily. Dry Matter Intake (DMI), milk yield and composition, feed efficiency, blood metabolites, ruminal and fecal pH, body weights and body condition scores were assessed. Dry matter intakes (P=0.01), and milk yields (P=0.03) were highest for cows fed diet containing 33% barley and 67% corn. Milk fat percentage (P=0.001), milk non fat solid percentage (P=0.17) and milk lactose content, percentagewise (P=0.2) were lowest for cows fed diet containing 100% barley. Ruminal pH (P=0.09) was lowest in cows fed diet containing 100% barley while highest for cows fed diet containing 100% corn. No significant differences were found in blood BHBA, NEFA, BUN and in total protein. Blood glucose (P=0.018) and albumin were recorded as lowest in cows fed diet containing 100% barley. These results most probably reflect a more optimal synchronization of dietary protein and energy for dairy cows when fed diets containing 33% barley and 67% corn in their early lactating diets rather than alfalfa hey formerly fed as the sole forage source.https://ijas.ut.ac.ir/article_23540_17397f76c707cd300612cac5898cbc36.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222Effect of Supplementation of Different Level Protein Diets with Rumen Protected Methionine and Lysine on Performance and Ruminal Parameters of Holstein Dairy Cows in Early LactationEffect of Supplementation of Different Level Protein Diets with Rumen Protected Methionine and Lysine on Performance and Ruminal Parameters of Holstein Dairy Cows in Early Lactation22123023541FAHosseinAbdi BenmarKamranRezayazdi0000-0002-1835-8612MehdiDehghan Banadaki0000-0001-8448-1371Journal ArticleThe objective of this study was to evaluate the effects of supplementation of different level protein diets with rumen protected methionine and lysine on performance and ruminal parameters in Holstein dairy cows when in their early lactation. Twenty one dairy cows in their early lactations were assigned to three treatments in a randomized block design experiment of a 35-d duration period. Diets were: 1) High protein diet containing 17.5% crude protein (CP), 2) Moderate protein diet bearing 16% CP along with 12 gr/d of rumen protected methionine, 3) Low protein diet with 14.5% CP plus 14 gr/d of rumen protected methionine and also 5 gr/d of rumen protected lysine. Dry matter intake, milk production, 3.5% fat corrected milk (3.5% FCM), percent content of milk fat, molar concentration of rumen volatile fatty acids and ruminal fluid pH were not significantly affected by diets. However, experimental treatments significantly affected percent of milk protein, milk urea nitrogen and ruminal ammonia concentration (P<0.05). Results finally indicated that feeding 16% CP diet with rumen protected methionine can lead to a better performance, in comparison with the other experimental diets.The objective of this study was to evaluate the effects of supplementation of different level protein diets with rumen protected methionine and lysine on performance and ruminal parameters in Holstein dairy cows when in their early lactation. Twenty one dairy cows in their early lactations were assigned to three treatments in a randomized block design experiment of a 35-d duration period. Diets were: 1) High protein diet containing 17.5% crude protein (CP), 2) Moderate protein diet bearing 16% CP along with 12 gr/d of rumen protected methionine, 3) Low protein diet with 14.5% CP plus 14 gr/d of rumen protected methionine and also 5 gr/d of rumen protected lysine. Dry matter intake, milk production, 3.5% fat corrected milk (3.5% FCM), percent content of milk fat, molar concentration of rumen volatile fatty acids and ruminal fluid pH were not significantly affected by diets. However, experimental treatments significantly affected percent of milk protein, milk urea nitrogen and ruminal ammonia concentration (P<0.05). Results finally indicated that feeding 16% CP diet with rumen protected methionine can lead to a better performance, in comparison with the other experimental diets.https://ijas.ut.ac.ir/article_23541_ac4e60ea6e45a09da42c7e8fb15ce613.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222The in vitro Organic Matter Digestibility of Pistachio Hull using Rumen Fluid in Taleshi SheepThe in vitro Organic Matter Digestibility of Pistachio Hull using Rumen Fluid in Taleshi Sheep23123723542FARezaLotfi NoghabiYousefRouzbehanJournal Article20130923This study was conducted to assess the in vitro organic matter digestibility (OMD) of pistachio hull using rumen fluid of Taleshi sheep. Animals were fed diets composed of 34% pistachio hull, 29% grape pomace, 32% alfalfa, and 5% grain barley. The chemical composition and phenolics' levels of pistachio hull, either Industrially Dried Pistachio Hull (IDPH) or sun Dried Pistachio Hull (SDPH) were determined. In vitro gas production for 24 h either with or without Polyethylene Glycol (PEG) addition was made use of estimate the OMD for IDPH or SDPH for either of the days 0, 3 or 30. For IDPH, the OMD on days 0, 3 or 30 (with no PEG) were respectively estimated as 54, 65.6 and 63.4, while with PEG application they were 65.2, 71.3 and 70.1 respectively (P<0.05). Also, the OMD for SDPH on days 0, 3 or 30 (with no PEG) were estimated as 52.6, 62.9 and 60.3 respectively and, which with an addition of PEG reached 62.1, 68.6 and 67.3 respectively (P<0.05). The results finally revealed that the microbial activity in the ruminal ecosystem of Taleshi sheep have the capability to degrade the hydrolysable tannin in pistachio hull to be later used as a source of energy.This study was conducted to assess the in vitro organic matter digestibility (OMD) of pistachio hull using rumen fluid of Taleshi sheep. Animals were fed diets composed of 34% pistachio hull, 29% grape pomace, 32% alfalfa, and 5% grain barley. The chemical composition and phenolics' levels of pistachio hull, either Industrially Dried Pistachio Hull (IDPH) or sun Dried Pistachio Hull (SDPH) were determined. In vitro gas production for 24 h either with or without Polyethylene Glycol (PEG) addition was made use of estimate the OMD for IDPH or SDPH for either of the days 0, 3 or 30. For IDPH, the OMD on days 0, 3 or 30 (with no PEG) were respectively estimated as 54, 65.6 and 63.4, while with PEG application they were 65.2, 71.3 and 70.1 respectively (P<0.05). Also, the OMD for SDPH on days 0, 3 or 30 (with no PEG) were estimated as 52.6, 62.9 and 60.3 respectively and, which with an addition of PEG reached 62.1, 68.6 and 67.3 respectively (P<0.05). The results finally revealed that the microbial activity in the ruminal ecosystem of Taleshi sheep have the capability to degrade the hydrolysable tannin in pistachio hull to be later used as a source of energy.https://ijas.ut.ac.ir/article_23542_860f5834f8e7f8e2834fc2957042760e.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222A Determination of the Optimal Slaughter Weight, Based on Carcass Characteristics for Ghezel and Mehraban Male LambsA Determination of the Optimal Slaughter Weight, Based on Carcass Characteristics for Ghezel and Mehraban Male Lambs23924523543FAJamshidIzadifardHadiAtashiJournal ArticleOne hundred and seventy four Ghezel and 130 Mehraban weaned male lambs were utilized to study the effect of on post weaning growth on slaughter weight and carcass traits. The lambs in each breed were randomly assigned to predetermined slaughter weight groups of 30, 40 or 50 Kg and were so far fattened as to reach their assigned slaughter weights. The average post weaning daily gain was estimated to be 185.82 (±54.88) grams, increasing significantly (p<0.05) with as increase in slaughter weight. Ghezel male lambs showed a significantly (p<0.05) more average daily gain, needing less time to reach their assigned slaughter weights than Mehraban ones. The dressing out percentage, hot carcass, cold carcass, carcass cuts' weights as well as cuts' percentages increased significantly (p<0.05) with increasing slaughter weight in both the examined breeds. The mean of dressing out was estimated to be 48.06 (±3.3) and varied between 45.78 (±0.31) and 51.36 (±0.41). All non-carcass fats and back fat thicknesses increased (p<0.05) significantly with increase in slaughter weight. The mean back fat depth varied from 2.56 (±0.217) to 6.64 (±0.286) mm for Ghezel slaughtered at a weight of 30 Kg and Mehraban slaughtered at weight of 50 Kg, respectively. Based on the obtained results, it can be concluded that the lambs of Ghezel can be fattened for more than 50 Kg, but slaughter weight of 50 Kg seems to be a proper target weight for Mehraban lambs at which to be slaughtered.One hundred and seventy four Ghezel and 130 Mehraban weaned male lambs were utilized to study the effect of on post weaning growth on slaughter weight and carcass traits. The lambs in each breed were randomly assigned to predetermined slaughter weight groups of 30, 40 or 50 Kg and were so far fattened as to reach their assigned slaughter weights. The average post weaning daily gain was estimated to be 185.82 (±54.88) grams, increasing significantly (p<0.05) with as increase in slaughter weight. Ghezel male lambs showed a significantly (p<0.05) more average daily gain, needing less time to reach their assigned slaughter weights than Mehraban ones. The dressing out percentage, hot carcass, cold carcass, carcass cuts' weights as well as cuts' percentages increased significantly (p<0.05) with increasing slaughter weight in both the examined breeds. The mean of dressing out was estimated to be 48.06 (±3.3) and varied between 45.78 (±0.31) and 51.36 (±0.41). All non-carcass fats and back fat thicknesses increased (p<0.05) significantly with increase in slaughter weight. The mean back fat depth varied from 2.56 (±0.217) to 6.64 (±0.286) mm for Ghezel slaughtered at a weight of 30 Kg and Mehraban slaughtered at weight of 50 Kg, respectively. Based on the obtained results, it can be concluded that the lambs of Ghezel can be fattened for more than 50 Kg, but slaughter weight of 50 Kg seems to be a proper target weight for Mehraban lambs at which to be slaughtered.https://ijas.ut.ac.ir/article_23543_bc633e62b0095c6ed17684297ee49db4.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222Effects of Feeding Different Levels of Alfalfa Hay and Corn Silage on Milk Production and Blood Metabolites in Holstein CowsEffects of Feeding Different Levels of Alfalfa Hay and Corn Silage on Milk Production and Blood Metabolites in Holstein Cows24725323544FAAmirAkbari AfjaniAbolfazlZali0000-0001-9654-2063MehdiGanjkhanlou0000-0002-1854-321XMehdiDehghan Banadaki0000-0001-8448-1371Journal ArticleThe effect of different levels of alfalfa hay and corn silage, in early lactation diet, on milk production and on milk components in Holstein cows was investigated. Fifteen Holstein cows (37 ±10 DIM) were taken in a completely randomized design experiment, lasting for 9 weeks. Three levels of hay and corn silage namely: 1) 10% alfalfa -30% silage corn (Diet 1), 2) 20% alfalfa -20% silage corn (Diet 2) and 3) 30% alfalfa -10% silage corn (Diet 3) former the treatments. The ratio of forage to concentrate was taken as the same (40: 60) in all the treatments. Cows were fed in Total Mixed Rations (TMR) and twice daily. They were milked 3 times a day at 02:00, 10:00, and 18:00 h. Milk production was recorded at each milking, but milk composition was weekly determined. Dry matter intake for each cow was daily assessed. Dry matter intake was higher (P<0.05) when cows fed diet 2 (23.20 kg per day) as compared with diets 1 (22.95 kg per day) and 3 (18.64 kg per day). Treatments affected milk production (P=0.014). Substituting corn silage with alfalfa hay increased the percentage of milk fat (P<0.05), but did not affect milk protein (P>0.05). Apparent total tract digestibility of dry matter (DM), organic matter, crude protein and neutral detergent fiber did not significantly differ among different dietary treatments (P>0.05). Blood parameters were not seriously affected by dietary treatments (P>0.05), although glucose content for Diet 1 was higher than that for Diet 2.The effect of different levels of alfalfa hay and corn silage, in early lactation diet, on milk production and on milk components in Holstein cows was investigated. Fifteen Holstein cows (37 ±10 DIM) were taken in a completely randomized design experiment, lasting for 9 weeks. Three levels of hay and corn silage namely: 1) 10% alfalfa -30% silage corn (Diet 1), 2) 20% alfalfa -20% silage corn (Diet 2) and 3) 30% alfalfa -10% silage corn (Diet 3) former the treatments. The ratio of forage to concentrate was taken as the same (40: 60) in all the treatments. Cows were fed in Total Mixed Rations (TMR) and twice daily. They were milked 3 times a day at 02:00, 10:00, and 18:00 h. Milk production was recorded at each milking, but milk composition was weekly determined. Dry matter intake for each cow was daily assessed. Dry matter intake was higher (P<0.05) when cows fed diet 2 (23.20 kg per day) as compared with diets 1 (22.95 kg per day) and 3 (18.64 kg per day). Treatments affected milk production (P=0.014). Substituting corn silage with alfalfa hay increased the percentage of milk fat (P<0.05), but did not affect milk protein (P>0.05). Apparent total tract digestibility of dry matter (DM), organic matter, crude protein and neutral detergent fiber did not significantly differ among different dietary treatments (P>0.05). Blood parameters were not seriously affected by dietary treatments (P>0.05), although glucose content for Diet 1 was higher than that for Diet 2.https://ijas.ut.ac.ir/article_23544_5aa86b4de7af02b2dda5de2fe8c60f47.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222Estimating Chemical Composition, Degradation Parameters and Gas Production of Persian Clover Nutrients at Different Plant's Growth StagesEstimating Chemical Composition, Degradation Parameters and Gas Production of Persian Clover Nutrients at Different Plant's Growth Stages25526423545FASeyed Mohammad MehdiTabatabaeiBehrouzNajaf-nejadPouyaZamani0000-0002-1051-2259AkbarTaghizadehAhmadAhmadiHassanAliarabi0000-0002-6182-173XJournal ArticleThis study was conducted to determine the chemical composition, degradability characteristics gas production as well as the phenomenon of the Persian clover (Trifolium resopinatum) when at some growth stages of the were early budding to full flowering, namely: early budding (I), full budding (II), early flowering (III) as well as full flowering stage (IV). Four fistulated Mehraban male sheep were taken as experimental specimens to estimate the degradability parameters. The results obtained from the chemical composition indicated that as the plant growth stage advanced, percentages of organic matter and NDF increased but the levels of CP, NFC and EE decreased significantly (P<0.05). The results concerning the degradability traits indicated that as the growth stage advanced the disappearance of the DM and CP contents and their effective degradability decreased. A similar trend was observed for the phenomenon of gas production, i.e. as the growth stage advanced, simultaneous with that, the digestible OM and metabolizable energy decreased significantly (P<0.05). It can be concluded, as deduced from the obtained results, that clover harvested at an early flowering stage benefits from more desirable nutritive qualities than when at the other tested growth stages.This study was conducted to determine the chemical composition, degradability characteristics gas production as well as the phenomenon of the Persian clover (Trifolium resopinatum) when at some growth stages of the were early budding to full flowering, namely: early budding (I), full budding (II), early flowering (III) as well as full flowering stage (IV). Four fistulated Mehraban male sheep were taken as experimental specimens to estimate the degradability parameters. The results obtained from the chemical composition indicated that as the plant growth stage advanced, percentages of organic matter and NDF increased but the levels of CP, NFC and EE decreased significantly (P<0.05). The results concerning the degradability traits indicated that as the growth stage advanced the disappearance of the DM and CP contents and their effective degradability decreased. A similar trend was observed for the phenomenon of gas production, i.e. as the growth stage advanced, simultaneous with that, the digestible OM and metabolizable energy decreased significantly (P<0.05). It can be concluded, as deduced from the obtained results, that clover harvested at an early flowering stage benefits from more desirable nutritive qualities than when at the other tested growth stages.https://ijas.ut.ac.ir/article_23545_a9ddacdd8891788c87fb2a7f31fa1ca0.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222Effect of Considering Nutrient Equivalency of a Commercial Multi Enzyme (Natuzyme-P) in Feed Formulation on Broiler Chicks’ PerformanceEffect of Considering Nutrient Equivalency of a Commercial Multi Enzyme (Natuzyme-P) in Feed Formulation on Broiler Chicks’ Performance26527323546FAMojtabaZaghari0000-0003-4440-3584SaeidKhalajiJournal ArticleThis experiment was conducted to evaluate the effect of the addition of a multi enzyme (Natuzyme-P) to corn-soybean based diets and to determine the enzyme's nutrient equivalency on broiler chicks’ performance. Ninety six day-old male broiler chicks were randomly assigned to a number of 24 battery cages in a completely randomized design. The chicks were grown up to 6 wk of age. Six diets (control, negative control, positive control along with three other diets made on the basis of 50, 100 and 120% nutrient equivalency of the enzyme) were formulated and fed to four pens, each pen housing 4 chicks up to 42 days of age. The control diet was formulated with no enzyme supplementation, the positive control diet contained sufficient nutrients for normal broiler growth along with the addition of enzyme as feed additive with an exclusion of the nutrient equivalency of the enzyme and while the negative control diet formulated with no enzyme supplement, but corrected to a nutrient equivalency level for the enzyme. Diets 50, 100 and 120% were prepared together with enzyme supplement and a correction of the diets to 50, 100 and 120% of nutrient equivalency of the enzyme. Body weight gain, feed intake and feed conversion ratio were assessed at 21, 35 and 42 d of age. Results indicated significant differences among the treatments in body weight gain (P<0.01) and feed conversion ratio at 21, 35 and 42 d of age (P<0.05). Carcass, breast, thigh, and abdominal fat relative weights were not affected by the treatments, but gizzard relative weight was. Immune response to PHA-P was significantly affected by treatments (P<¬0.01). In summary, addition of Natuzyme, in comparison with the negative control diet, improved broiler chicks performance, and the treatment with enzyme supplement, accompanied by correction up to 50% of nutrient equivalency of the enzyme resulted in the best response. Correcting up to 50% of nutrient equivalency of the enzyme reduced the feed cost per kg of body weight gain for 4.4 and 5% as compared with the control and positive control diets.This experiment was conducted to evaluate the effect of the addition of a multi enzyme (Natuzyme-P) to corn-soybean based diets and to determine the enzyme's nutrient equivalency on broiler chicks’ performance. Ninety six day-old male broiler chicks were randomly assigned to a number of 24 battery cages in a completely randomized design. The chicks were grown up to 6 wk of age. Six diets (control, negative control, positive control along with three other diets made on the basis of 50, 100 and 120% nutrient equivalency of the enzyme) were formulated and fed to four pens, each pen housing 4 chicks up to 42 days of age. The control diet was formulated with no enzyme supplementation, the positive control diet contained sufficient nutrients for normal broiler growth along with the addition of enzyme as feed additive with an exclusion of the nutrient equivalency of the enzyme and while the negative control diet formulated with no enzyme supplement, but corrected to a nutrient equivalency level for the enzyme. Diets 50, 100 and 120% were prepared together with enzyme supplement and a correction of the diets to 50, 100 and 120% of nutrient equivalency of the enzyme. Body weight gain, feed intake and feed conversion ratio were assessed at 21, 35 and 42 d of age. Results indicated significant differences among the treatments in body weight gain (P<0.01) and feed conversion ratio at 21, 35 and 42 d of age (P<0.05). Carcass, breast, thigh, and abdominal fat relative weights were not affected by the treatments, but gizzard relative weight was. Immune response to PHA-P was significantly affected by treatments (P<¬0.01). In summary, addition of Natuzyme, in comparison with the negative control diet, improved broiler chicks performance, and the treatment with enzyme supplement, accompanied by correction up to 50% of nutrient equivalency of the enzyme resulted in the best response. Correcting up to 50% of nutrient equivalency of the enzyme reduced the feed cost per kg of body weight gain for 4.4 and 5% as compared with the control and positive control diets.https://ijas.ut.ac.ir/article_23546_c1aa157f9e8516370e3345f226ef62fc.pdfپردیس کشاورزی و منابع طبیعی دانشگاه تهرانIranian Journal of animal Science2008-477342320111222Effect of Various Levels of Barley and Multi Enzyme on Metabolizable Energy, Dry Matter and Protein Digestibility of Diets and Performance of Broiler ChicksEffect of Various Levels of Barley and Multi Enzyme on Metabolizable Energy, Dry Matter and Protein Digestibility of Diets and Performance of Broiler Chicks27528323547FAAli-asgharSakiSaraMirzaei GoudarziShahabGhaziMohammad MehdiMoeiniFatemehSahebi AlaJournal ArticleThis experiment was carried out for a determination of metabolizable energy and the effect of the Grind multienzyme on in-vitro dry matter and protein digestibility in diets, and as well on performance of broiler chicks. A number of 800 day old unsexed Arbor Acres broilers were placed in 8 treatments and 4 replicates (25 chicks each). A completely Randomized Design (CRD) of a factorial arrangement (4×2), along with 4 levels of barley (0, 10, 20 and 30%) and 2 levels of enzyme, (0 and 500 g/ton) were modulated for a duration of 42 days. Apparent Metabolizable Energy (AME), the same factor (AME) corrected by nitrogen (AMEn), True Metabolizable Energy (TME), and true metabolizable energy corrected by nitrogen (TMEn) as well as digestibility of barley protein (based on dry matter) were recorded as 2886.6, 3015.8, 3624.2, 3205.5 kcal/kg and 57.95% respectively. Feed intake rate, in control treatment (2776.66g), was significantly (p<0.05) higher than those in 10% barley (no enzyme containing), and 30% barley (enzyme containing). Body weight recorded for 0% barley treatment (2077.83g) was significantly higher than those for 20 and 30% treatments (p<0.05). The results finally indicate that 0 and 10% barley along with Grind enzyme supplementation treatments lead to desirable feed conversion ratio, increased body weight as well as improved growth rates.This experiment was carried out for a determination of metabolizable energy and the effect of the Grind multienzyme on in-vitro dry matter and protein digestibility in diets, and as well on performance of broiler chicks. A number of 800 day old unsexed Arbor Acres broilers were placed in 8 treatments and 4 replicates (25 chicks each). A completely Randomized Design (CRD) of a factorial arrangement (4×2), along with 4 levels of barley (0, 10, 20 and 30%) and 2 levels of enzyme, (0 and 500 g/ton) were modulated for a duration of 42 days. Apparent Metabolizable Energy (AME), the same factor (AME) corrected by nitrogen (AMEn), True Metabolizable Energy (TME), and true metabolizable energy corrected by nitrogen (TMEn) as well as digestibility of barley protein (based on dry matter) were recorded as 2886.6, 3015.8, 3624.2, 3205.5 kcal/kg and 57.95% respectively. Feed intake rate, in control treatment (2776.66g), was significantly (p<0.05) higher than those in 10% barley (no enzyme containing), and 30% barley (enzyme containing). Body weight recorded for 0% barley treatment (2077.83g) was significantly higher than those for 20 and 30% treatments (p<0.05). The results finally indicate that 0 and 10% barley along with Grind enzyme supplementation treatments lead to desirable feed conversion ratio, increased body weight as well as improved growth rates.https://ijas.ut.ac.ir/article_23547_7dfbfb4a386b98740005488c55f5ccbe.pdf