hossein ghorbani; rasoul vaez torshizi; naser emam jomeh kashan
Volume 40, Issue 1 , June 2009
Abstract
The purpose of this study was to investigate the relationship of maternal breeding values of the weight of day-old chick chicks in a commercial broiler line with egg traits including yolk fatty acids. Maternal breeding values of 63 hens of known pedigree were estimated through an animal model, containing ...
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The purpose of this study was to investigate the relationship of maternal breeding values of the weight of day-old chick chicks in a commercial broiler line with egg traits including yolk fatty acids. Maternal breeding values of 63 hens of known pedigree were estimated through an animal model, containing direct additive genetic effect, maternal additive genetic effect, maternal common environmental effect and covariance between direct and maternal additive genetic effects, through DFREML program employing 6476 records of day-old chick weights. Hens were divided into 3 genetic groups (low, LGG; medium, MGG; and high, HGG) on the basis of estimated maternal breeding values. From the hens, 126 eggs (2 eggs from each hen) were collected at 32 weeks of age for an assessment of egg quality and quantity traits (egg weight, shell thickness, shell strength, shell weight, yolk weight, yolk percentage, albumin weight and albumin percentage) as well as yolk fatty acids (palmetic, palmitoleic, estearic, oleic, linoleic and linolenic acids). Analysis of variance was carried out through GLM procedure and differences among the means evaluated using Tukey method. Egg, shell, yolk, and albumin weights as well as albumin percentage were higher (p
mohammad razm kabir; ardeshir nejati javaremi; mohammad moradi shahr babak; amir rashidi; mohammad bagher sayad nejad
Volume 40, Issue 1 , June 2009
Abstract
Data related to Holstein dairy cattle from 1987 to 2004 were obtained from Animal Breeding Center of Iran to estimate the genetic and phenotypic trends. Variance components and genetic parameters of the first lactation records were estimated using Restricted Maximum Likelihood Method and AIREML algorithm ...
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Data related to Holstein dairy cattle from 1987 to 2004 were obtained from Animal Breeding Center of Iran to estimate the genetic and phenotypic trends. Variance components and genetic parameters of the first lactation records were estimated using Restricted Maximum Likelihood Method and AIREML algorithm through MATVEC program. Animal breeding values were predicted through multiple-trait animal model. Estimates of heritability for milk, fat and protein yields were 0.27, 0.22 and 0.25, respectively. Genetic trend was estimated as the linear regression of BLUPs of the breeding values of animals on the birth year. The estimate of genetic trend for milk yield was 33.84±2.10kg, for fat yield 0.64±0.05kg and for protein yield it was 1.00±0.08kg. Average phenotypic trend for milk, fat and protein yields were 122.28, 4.42 and 3.06 kg, respectively. Acceptable genetic improvement for milk yield, while low genetic trends for fat and protein yield were observed in Holstein cattle in Iran.
sahereh jozi shekalgoorabi; abdol ahad shadparvar
Volume 40, Issue 1 , June 2009
Abstract
To test the effect of culling herd life from the breeding goal function, 4 different selection indices were established as: index 1: using Milk production (Milk), Fat percentage of milk (fat%) and Rear Udder Height (Ruh); index 2: using Milk , fat% and Fore teat placement (Ftp), index 3: using Milk, ...
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To test the effect of culling herd life from the breeding goal function, 4 different selection indices were established as: index 1: using Milk production (Milk), Fat percentage of milk (fat%) and Rear Udder Height (Ruh); index 2: using Milk , fat% and Fore teat placement (Ftp), index 3: using Milk, fat% and Fore udder attachment (Fua); and index 4: using Milk, fat%, Ruh, Ftp and Fua) under two different selection goals, one of which included Milk, fat% and herd life while the other one was excluded of herd life. Calculations were made in economic situations of year 1995 and 2000. Response to selection and selection accuracy resulted from the above mentioned indices and under two economic situations revealed that exclusion of herd life would result in a decrease in genetic gain in the breeding goal function except when excluded from index 4 and under 1995 conditions, although by excluding this trait the selection accuracy may even increase.
hossein abdi benmar; kamran reza yazdi; ali nikkhah
Volume 40, Issue 1 , June 2009
mojtaba nobakht; fariborz khajali; mehrab faraji nafchi
Volume 40, Issue 1 , June 2009
Abstract
Three hundred and sixty broiler chicks (Ross 308) were employed in an experiment from 6 to 49 days of age to evaluate the effect of replacing canola meal for soybean meal either with or without enzyme supplementation. Dietary treatments included 5 substitution levels (0, 25, 50, 75 and 100%) at two enzyme ...
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Three hundred and sixty broiler chicks (Ross 308) were employed in an experiment from 6 to 49 days of age to evaluate the effect of replacing canola meal for soybean meal either with or without enzyme supplementation. Dietary treatments included 5 substitution levels (0, 25, 50, 75 and 100%) at two enzyme concentrations of: 0 and 400 g/ton in a 5×2 factorial layout experiment. The enzyme mixture contained mainly ?-glucanase activity and to some extent xylanase activity. Data were analyzed in a completely randomized design. Body weight gain during 6 to 21d was significantly (P
mehdi ganj khanloo; kamran reza yazdi; gholam reza ghorbani; hossein moravej; mehdi dehghan banadaki; mohammad reza emami
Volume 40, Issue 1 , June 2009
Abstract
This study was conducted to evaluate production response of early lactating cows to rumen protected fats. Twelve (nine multiparous and three primiparous) Holstein cows (26±4 d in milk) were empolyed in a replicated 3×3 Latin Square Design of 21-d periods. Each period consisted of 14 days of adaptation ...
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This study was conducted to evaluate production response of early lactating cows to rumen protected fats. Twelve (nine multiparous and three primiparous) Holstein cows (26±4 d in milk) were empolyed in a replicated 3×3 Latin Square Design of 21-d periods. Each period consisted of 14 days of adaptation and 7 days of sampling. Cows received diets containing either one of two types of protected fats or no supplemental fat. Cows in group 1 (control) were fed Total Mixed Ration (TMR) of 20% corn silage, 20% alfalfa hay, and 60% concentrate mix. Cows in group 2 were fed the TMR containing 3% prilled protected fat (Energizer-10). Cows in group 3 were fed the TMR containing 3.5% Ca salt of protected fat (Magnapac). Intake of Dry Matter (DM), Organic Matter (OM) and Neutral Detergent Fiber (NDF) were decreased by rumen protected fat (P < 0.05) in multiparous cows (DMI: 25.7, 24.1, and 23.9 kg/d for control, prilled fat, and ca salt of fat, respectively); intake of NEL in all the cow population and intake of DM, OM and NDF in primiparous cows were similar for all diets (P > 0.05). Production of milk and 3.5% FCM in primiparous and multiparous cows as well as milk protein, fat, lactose and total solid percentages and yields (kg/d) were not affected by fat supplements (P > 0.05). The BCS and BW changes were similar for all diets in multiparous and primiparous cows (P > 0.05). In multiparous cows, feed efficiency (3.5% FCM/DMI) was higher for cows fed supplemental fat diets (P < 0.05) than for control samples. Fat fed cows were more efficient than those fed with control diet. In primiparous cows supplemental fat did not influence feed efficiency (P > 0.05). Fat supplements did not influence either chewing behavior or total time spent ruminating and eating (P > 0.05). The results indicate that supplementation of early lactating diet with rumen protected fat decreases feed intake and improves milk efficiency but this is not true for primiparous cows.
masood didar khah; mehrdad mohammadi; mokhtar mehdizadeh
Volume 40, Issue 1 , June 2009
Abstract
The objective of this study was to determine the best time for artificial insemination in Taleshi ewes. One hundred and fifty ewes were randomly allotted to three groups (n=50/per group). Estrus was synchronized with intravaginal insertion of Controlled Internal Drug Release (CIDR) for 14 days. At the ...
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The objective of this study was to determine the best time for artificial insemination in Taleshi ewes. One hundred and fifty ewes were randomly allotted to three groups (n=50/per group). Estrus was synchronized with intravaginal insertion of Controlled Internal Drug Release (CIDR) for 14 days. At the time of CIDR removal PMSG (300IU) was injected to the ewes. The first (AI28), second (AI40) and third (AI52) groups were inseminated (cervically) 28, 40 and 52 hours after CIDR removal, respectively. All ewes showed estrus singns about 24 hours after CIDR withdrawal. The results of insemination efficiency and reproduction performance indicated that in prolificacy and twin bearing traits there did not exist any statistical difference among the groups. Insemination efficiency, lambing rate and fertility made significant differences among the groups (P
morteza sataii mokhtari; amir rashidi; mohammad reza mohammad abadi; hossein moradi shahr babak
Volume 40, Issue 1 , June 2009
Abstract
In this study the data of 2332 lambs from 815 dams and 61 sires, collected during 1993-2004 in Kermani sheep breeding station were used to estimate phenotypic, genetic and environmental trends for birth weight (BW), weaning weight (WW), 6 months weight (6MW), 9 months weight (9MW) and yearling weight ...
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In this study the data of 2332 lambs from 815 dams and 61 sires, collected during 1993-2004 in Kermani sheep breeding station were used to estimate phenotypic, genetic and environmental trends for birth weight (BW), weaning weight (WW), 6 months weight (6MW), 9 months weight (9MW) and yearling weight (YW). Heritability estimates were determined for each trait using derivative free REML procedures under univariate animal model. By excluding or including maternal genetic effects or maternal permanent environmental effects, six different models were fitted for each trait. Likelihood ratio test was used to determine the appropriate model. This test indicated that the model including direct and maternal genetic effects, without covariance between them, was the appropriate model for BW. The model including direct genetic effects and maternal permanent environmental effects was the most appropriate model for WW, 6MW and 9MW. The model including direct genetic effects was the most appropriate model for YW. Phenotypic, genetic and environmental correlations were estimated under multivariate analysis using the most appropriate model for each trait. Breeding values were estimated under univarite and multivariate analyses. Genetic, phenotypic and environmental trends were estimated by regression of the estimated mean of breeding values, phenotypic mean and difference between estimated mean of breeding values and phenotypic mean on birth year, respectively. The average additive direct genetic trends for BW, WW, 6MW, 9MW, YW in univariate and multivariate analyses were 0.53±0.30 and 0.84±1.14, 96.41±18.27 and 101.29±37.41, 88.24±26.11 and 90.51±48.34, 24.35±10.68 and 29.76±11.49 and 31.53±10.43 and 35.18±12.58 gr per year, respectively. The estimates of maternal additive genetic trend for BW in univariate and multivariate analyses were 3.07±1.21 and 2.91±1.67 gr per year, respectively.
jamshid izadi far; mohammad dadpasand
Volume 40, Issue 1 , June 2009
Abstract
The effect of crossbreeding between Ghezel and Mehraban on growth performance and carcass characteristics was studied for two consecutive years using 162 purebred and crossbred lambs. The four groups of lambs involved in the study were purebred Mehraban (MM), purebred Ghezel (GG), crossbred Ghezel ram×Mehraban ...
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The effect of crossbreeding between Ghezel and Mehraban on growth performance and carcass characteristics was studied for two consecutive years using 162 purebred and crossbred lambs. The four groups of lambs involved in the study were purebred Mehraban (MM), purebred Ghezel (GG), crossbred Ghezel ram×Mehraban ewe (GM) and crossbred Mehraban ram×Ghezel ewe (MG). The lambs were fed with grazing of cereal (wheat and barely) pasture, alfalfa as well as with concentrate for 84 days. The results indicated that crossbreeding had significant (p
hamid reza mirzaii alamooti; kamran rezayazdi; hamid amanloo; armin tohidi
Volume 40, Issue 1 , June 2009
Abstract
Sixty eight Holstein cows, 38 primiparous and 30 multiparous ones, were employed in a randomized complete block design, blocked to evaluate the effects of 2 diets in various ruminal fermentable carbohydrate sources (Ground Corn vs Rolled Wheat) on rumen fermentation and performance during preparturient ...
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Sixty eight Holstein cows, 38 primiparous and 30 multiparous ones, were employed in a randomized complete block design, blocked to evaluate the effects of 2 diets in various ruminal fermentable carbohydrate sources (Ground Corn vs Rolled Wheat) on rumen fermentation and performance during preparturient period. Primiparous and multiparous cows were blocked by parity. The cows were fed diets as total mixed ration with similar energy and crude protein content including 1) 18.57% GC; 2) 18.57% RW from -23.1 ± 9 d relative to expected calving until calving. Followeing calving, all the animals received the same lactation diet for 28 days. The results revealed that, dry matter intake, energy intake, energy balance, and body condition score did not differ between multiparous cows fed either the ground corn or rolled wheat diet at preparturient period. Dry matter intake, energy intake, and energy balance were lower for primiparous cows fed the rolled wheat diet at prepartum period (p
a'azam mir heidari; yousef rouzbehan; hassan fazaeli
Volume 40, Issue 1 , June 2009
Abstract
The effects of replacement of alfalfa hay with pistachio by-product (PB) at 0, 25, 50, and 75% (DM basis) on the ruminal parameters, Dry Matter Intake (DMI) of female Rayini goats, after kidding, and on the Live Weight Gain (LWG) of their kids were investigated. Five single-bearing female Rayini goats ...
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The effects of replacement of alfalfa hay with pistachio by-product (PB) at 0, 25, 50, and 75% (DM basis) on the ruminal parameters, Dry Matter Intake (DMI) of female Rayini goats, after kidding, and on the Live Weight Gain (LWG) of their kids were investigated. Five single-bearing female Rayini goats each with a single kid were employed in each level of replacement. The basal diet contained barley and alfalfa hay, the Metabolizable Energies (ME) of which were respectively 9.9 and 13.4 MJ/Kg of OM, and CP of 146 and 114 g/Kg of DM. Diets were offered to animals for ninety days. Throughout the study, DMI of female Rayini goats was measured on a daily basis, while LWG of kids assessed fortnightly. Conventional chemical composition, phenolics and their capacity to precipitate protein (PPP), In Vitro Gas Production for 24 h (IVGP), estimated Organic Matter Digestibility (OMD) and ME of the experimental diets were determined on a regular basis. Data were analyzed using the completely randomized design. As the level of PB increased in the diets, water soluble carbohydrates, neutral detergent fiber, acid detergent fiber and lignin(sa) were significantly (P
leyla zartash; ahmad zare shahneh; abolfazl zali; rooh-o-lah gaykani; javad poor reza
Volume 40, Issue 1 , June 2009
Abstract
The present study was carried out to investigate the effect of corn replacement by different levels of wheat with supplementation of phytase with reduced phosphorus level for laying hens. Two hundred seventy nine layer hens (the strains of Hy-line W36) at the 53th week of age, selected based on the same ...
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The present study was carried out to investigate the effect of corn replacement by different levels of wheat with supplementation of phytase with reduced phosphorus level for laying hens. Two hundred seventy nine layer hens (the strains of Hy-line W36) at the 53th week of age, selected based on the same egg production percentage and body weight, assigned in a factorial arrangement with completely randomized design of 30 treatments each in 3 replicates. The factors included 5 levels of replacements (0, 25, 50, 75, 100% replacement of corn by wheat), phytase enzyme in three levels (0, 500, 1000 ftu/kg) and two levels of non phytate phosphorus (0.70% and 0.55% requirement) along with one corn soybean meal control diet. The experiment was carried out at 3 periods, each of 28 days. Egg production percentage, egg weight, feed conversion ratio, shell percentage, shell strength, shell thickness and toe ash were assessed. The results indicated that the effects of substitution wheat on egg production, Feed Conversion Ratio (FCR), shell strength, shell thickness and toe ash were significant (P