Maternal effects on body weight at 8 weeks of age (BW8W), egg weight (EW), egg number (EN) and age at sexual maturity (ASM) from 13 generations of Mazandaran native fowl were investigated. The data were analyzed using restricted maximum likelihood procedures and animal model with DFREML software. With or without using maternal effects, six different animal models were fitted. Likelihood ratio test wase employed to determine the most appropriate model. For all traits, maternal additive genetic and environmental effects together with the covariance between direct and maternal additive genetic effects were important. Direct heritability (h2a) ranged from 0.130 (for EN) to 0.506 (for EW). These estimates for maternal heritability (h2m) and maternal environmental variance as a proportion of the phenotypic variance (c2) varied from 0.008 (for EW) to 0.034 (for ASM), and 0.020 (for EN) to 0.047 (for BW8W), respectively. Also for all traits c2 was higher than h2m. The correlation between direct and maternal additive genetic effects (ram) were all negative and -0.737, -0.692, -0.590 and -0.396 for EN, EW, ASM and BW8W, respectively. The results indicated that ignoring maternal effects in the analysis of BW8W tended to overestimate direct additive genetic variance and heritability, but for EW, EN and ASM ignoring the covariance between direct and maternal additive genetic effects caused a decreased in those estimates.

The main objective of the dairy farmers is the improvement of production. Selection for production traits can result in deterioration of fitness traits (like udder disorders). Therefore, the traits such as reproduction and conformation should be considered in breeding programs. The data of first lactation production, reproduction and conformation traits of two Agro-Industrial Holstein dairy farms in Tehran province were used to investigate the genetic and phenotypic parameters.The Animal Model consisted of herd-year-season of calving (fixed), animal and residual effects (random).The age at first calving was used as a covariate. The average of 305d-2x milk and fat yield were 7019 (16) and 212.4 (0.6) kg, respectively. The average of fat percentage was 3.1 (0.01) percent. The average of calving interval was 407 (1) days. The average of age at first calving was 25.8 (0.02) months. The average of all conformation traits were within the range of values of Iranian Holstein cows. The heritability of milk and fat yield, fat percentage calving interval and age at first calving were 0.27 (0.3), 0.17 (0.3), 0.32 (0.04), 0.02 (0.01) and 0.03 ( 0.01), respectively. The range of heritability estimates for conformation traits were 0.15 (chest width and rear leg side view) to 0.41 (stature). The genetic correlation between first lactation milk yield and fat yield, fat percentage, calving interval and age at first calving were 0.72, -0.70, 0.17 and -0.03, respectively. There was a positive genetic trend for all production and reproduction traits (except fat percentage). The genetic trend for milk yield was 59.6 kg per year and for fat percentage was -0.01 percent per year.

The effect of genetic and non-genetic factors on body weight at 6 weeks (BW6WT), egg weight (EWT), age at sexual maturity (ASM) and egg production from 25 to 50 weeks (EP) of a commercial broiler line were investigated using restricted maximum likelihood procedure through estimation of direct and maternal additive genetic and common environmental variances. Six different animal models were taken into account by including maternal direct additive or environmental effects in the models of analysis. Likelihood ratio test was used to determine the most appropriate model. For BW6WT, maternal additive and common environmental effects together with the covariance between direct and maternal additive genetic effects were significant. For this trait, direct heritability (h2a), maternal heritability (h2m ), maternal environmental variance as a proportion of the phenotypic variance (C2) and the correlation between direct and maternal additive genetic effects (ram) were 0.350, 0.050, 0.040 and-0.670, respectively. For EWT, ASM and EP, only maternal additive genetic effects were important, in addition to the direct additive genetic effects. The estimates of h2a and h2m were 0.470 and 0.130 for EWT, 0.150 and 0.060 for ASM, and 0.240 and 0.05 for EP, respectively. The results of this study indicated that ignoring the maternal effects in the analysis tended to overestimate direct additive genetic variance and heritability for all traits.

In the research the genetic investigation productive and reproductive traits and changes trend the traits in years, seasons and different lactation periods and genetic evaluation cows and bulls of 785 records for milk and 665 records for fat yield and reproductive information during years 1998 to 2003 of 207 dairy cows ghezlagh farm aboureyhan campus (university of Tehran) studied. The least square mean and standard error (LSM±SE) of milk yield (3x, 305, ME) and fat yield were 6305.6±87.7 and 206.1±1.7 kg, respectively. The least square means (± SE) of calving interval, open days, dry days, age at first calving and gestation length were 403.2 (±6.7), 117.5 (±6.8), 86.8 (±7.3), 760.3 (±9.7), 278.1 (±0.7), respectively and insemination rate was 1.8 (±0.04). The effect of environmental factors of lactation period on milk production, persistency and insemination rate, year of parturition on milk and fat production, calving interval, insemination rate and age at first calving, dry days, and calving season on milk production and insemination rate were significant. Estimated heritabilities and standard error for milk and fat yield using Repeatability Record Animal Model (RRAM), were 0.22 (±0.12) and 0.29 (±0.05), respectively. Genetic and environmental trend of production traits during years 1998 to 2003 were positive. The breeding value of the animals for production traits predicted with Animal Model method and the superior families were ranked.

microsatellites are widely used for designing of gene mapping, genetic distance estimation and evaluation of different animals. The aim of present study was investigation of association of microsatellite markers polymorphism with production and reproduction traits of Sanjabi sheep. Blood samples were randomly collected from 78 ewes and 22 rams of Sanjabi sheep and transported to laboratory. After extraction of DNA by salting out method, 11 microsatellite loci (GC101, LSCV043, TGLA377, CSSM47, OarFCB128, OarAE101, BM1329, BM143, OarHH55, OarHH35 and OarHH64) were amplified by specific primers and polymerase chain reaction. By electrophoresis of productions on 8% polyacrylamide gel, different alleles were recognized and then data were analyzed by using of software program SAS 9.1 and POPGENE. The mean of number of observed and effective alleles were 5.82 and 4.05, respectively. PIC amount of markers was in range of 0.63 (TGLA377) to 0.82 (OarHH35). The mean of observed and expected heterozygosity was 0.64 and 0.77 in between loci, respectively. Also, the statistical analysis showed that genotypes associated with markers TGLA377, CSSM47, OarFCB128, OarHH35, OarHH55 and OarHH64 have had a significant effect (P<0.01) on the twinning of Sanjabi sheep and genotypes associated with markers GC101, LSCV043, TGLA377, CSSM47, OarAE101, BM143 and OarHH64 have had a significant effect (P<0.05) on body weight gain traits in different ages. Due to the findings, it can be concluded that except of marker BM1329, other studied markers are suitable on body weight gain and twinning traits in breeding programs of Sanjabi sheep.

In this study, the genetic and phenotypic trend of milk and fat production traits were estimated form 94121 cows’ first lactation records and that for age at first calving and calving interval traits were estimated from 41900 cows’ reproduction records. Data related to Iranian Holstein dairy cattle from 1995 to 2003. Data were analyzed, using univariate and mulitivariate animal model with genetic group effects. The heritability of milk yield, fat yield and fat percentage, age at first calving and calving interval were 0.29 (±0.01), 0.22 (±0.01), 0.38 (±0.01), 0.055 (±0.01) and 0.034 (±0.005), respectively. The linear regression of average breeding values and phenotypic values of cows for a trait on birth year provided an estimate of genetic and phenotypic trend, respectively. There genetic trend for milk yield, fat yield and Calving Interval were 53.5 kg, 1.07kg and 0.46 day, respectively. Their trend for fat percentage and Age at First Calving were -0.011% and -0.23 day, respectively. There was a positive phenotypic trend for milk yield, fat yield and fat percentage. This trend was negative for Age at First Calving and Calving Interval.

In this research, the effect of environmental factors on reproduction traits such as calving interval, days dry, number of days open, was studied. Data collected from 163 buffalo herds from Guilan, Mazandaran, West Azerbaijan, Khuzestan and Ardebil provinces by Animal Breeding Center of Iran during 15 years (1992-2008). The environmental factors were herd nested within state, lactation period, age at calving, season of calving, year of calving, state and season of drying were analysed by GLM procedure in SAS software. The average and standard errors of calving interval, days dry and number of days open traits were 440.88±1.11 day, 163.10±0.65 day, 149.05±1.24 day, respectively. Results indicated that the season of calving significantly influenced all traits, except the calving interval. The effect of other factors on all traits was significant.

Records of 3257 lambs of Zandi sheep breed, collected from 1991to 2003 in Khojir rearing and breeding station of Tehran province were used to estimate the genetic parameters for growth traits (birth weight, weaning weight, body weight at 6, 9, and 12 months of ages) along with composite reproduction traits (total weight of lamb weaned per ewe joined through three consecutive parities. Based on univariate analysis, the best model for birth and weaning weights was model 3 (including direct and maternal additive genetic effects). Modell (including direct additive genetic effect) was the most appropriate model for body weight at 6, 9 and 12 months of ages. According to this model, the direct heritability estimates for growth traits (from birth weight to body weight at 12 months of age) were 0.08±0.04, 0.20±0.05, 0.29±0.06, 0.25±0.06 and 0.35±0.07, respectively. Maternal heritabilities of 0.17±0.02 and 0.06±0.03 wares obtained for birth and weaning weights, respectively. Genetic parameters for composite reproduction traits were estimated using model 1. Heritability estimates of 0.06±0.08, 0.03±0.09, and 0.08±0.11 were obtained from first to third parity, respectively. Covariance components and correlations between growth and composite reproduction traits were estimated on the basis of multivariate analysis, using the most appropriate model in univariate analysis. The highest additive genetic correlation among growth and composite reproduction traits was obtained between weaning weight and TWW2/EJ (0.99). The corresponding estimate for additive genetic correlation among growth traits was 0.99 (between weaning and body weights at 6 months of age). The results of this study indicated that selection on the basis of weaning weight can improve the post weaning and composite reproduction traits.

In this research, production and reproduction performance data of 526 buffalo herds of Khuzestan, collected by the deputy of improving livestock production of Agriculture Organization of Khuzestan from 1992 to 2009, were studied. The GLM method of SAS software was used to study the effect of none genetic factors on considered traits. Variance components and hertabilities were also estimated by restricted maximum likelihood using DFREML software package. The average and standard error were estimated as 1939.76±6.5 kg for milk yield, 120.27±0.48 kg for fat yield, 6.1±0.01 % for fat percentage, 83.94±0.40 kg for protein yield, 3.9±0.004 % for protein percentage, 200.34±0.44 days for lactation length, 4.68±0.02 kg for milk yield per day of calving interval and 9.58±0.04 kg for milk yield per day of lactation length, respectively. The average and standard error of reproductive traits were estimated as 240.27±1.89 days for dry period, 156±2.05 days for the number of open days, 465.21±2.05 days for calving interval and 3.68±0.02 years for age at first calving, respectively. The effect of herd, calving year and parity were significant for all traits. However, calving season had not significant effect on protein percentage, calving interval and the number of open days. The estimated heritability coefficient was zero for all studied traits, except age at first calving with heritability of 0.21. Some factors such as inappropriate feeding and breeding management in these buffalo herds and particularly errors in milk recording, pedigree registering and relationships were some of main reasons for this estimating.