Introduction: The unavoidable mating of related animals in closed populations leads to accumulation of INBREEDING and decreased genetic diversity. The loss of diversity and an increase in homozygosity may result in decreased productions and fitness of inbred animals. It is apparent that different breeds as well as different traits vary in their response to INBREEDING (Mackinnon 2003). It is important to account for the effects of INBREEDING in populations undergoing selection to properly adjust the breeding program for the potential reduction in performance. The objectives of this study were to estimate the INBREEDING trend and INBREEDING depression on growth traits of Iranian Moghani sheep. Materials and methods: Pedigree records on the research flock of the Iranian Moghani sheep kept at the Jafarabad Breeding Station from 1990 to 2016 were used for analysis. The pedigree completeness index (PCI) proposed by MacCluer et al. (1983) was used to describe the degree of completeness of pedigree. In addition, for each INDIVIDUAL, the number of complete generations equivalent (CGE) was computed as the sum of (1/2) n, where n is the number of generations separating the INDIVIDUAL to each known ancestor (Maignel et al. 1996). INBREEDING coefficient for all animals were estimated using the method of Meuwissen and Luo (1992). Average INBREEDING coefficients per year were computed and annual increases in INBREEDING were estimated by linear regression over time. INDIVIDUAL increase in INBREEDING coefficients (Δ Fi) was calculated according to the methodology described by Gonzá lez-Recio et al. (2007) and modified by Gutié rrez et al. (2009) as ∆ Fi = 1 √ 1 − Fi t i − 1 , where Fi is the INBREEDING coefficient of INDIVIDUAL i and ti is the number of known equivalent generations for this INDIVIDUAL. The analyzed traits for estimating INBREEDING depression were birth weight (BW), 3-month weight (3MW), 6-month weight (6MW), 9-month weight (9MW), and yearling weight (YW). For estimating the INBREEDING depression, only animals with PCI > 0. 6 were kept in all analyses. All animals were grouped into three classes: first class included non-inbred animals (F=0); second class included animals with 00. 10. Then INBREEDING included in the model as the categorical fixed effects. Also, in a separate analysis, INBREEDING and INDIVIDUAL increase in INBREEDING were included in the model as a linear covariate. Results and discussion: Proportion of animals with F=0, 00. 10 in all population were 78%, 21%, and 1%, respectively. These proportions in animals with PCI>0. 6 were 23%, 74% and 3%, respectively. Average INBREEDING of all and inbred indivduals within the animals with PCI>0. 6 were 1. 00% and 1. 32%, respectively. The rate of INBREEDING is more important than estimated level of INBREEDING in genetic management of the population (Falconer and Mackay 1996; Bijma 2000). The evolution of the mean INBREEDING, pedigree completeness index (PCI), and complete generations equivalent (CGE) of animals across years of birth are given in Figure 1. Trend of INBREEDING was more coincident with PCI than CGE. Such a discrepancies in the behavior of two index of pedigree completeness could be attributed to the differences in the computation methods. From the linear regressions estimated, the rate of INBREEDING was 0. 03% (P < 0. 01) per year equal to 0. 12% per generation in the studied period. This estimated rate of INBREEDING was less than the critical levels (1% per generation) recommended by FAO (1998) and Bijma (2000). The estimated rate of INBREEDING for Moghani sheep in this study was similar to those reported by Hossein-zadeh (2012) and Gholambabaeian et al. (2012) for this breed. Also it was close to values reported for Iranian LoriBakhtiari, Sangsari and Zandi sheep (Almasi et al. 2014; Rashedi Dehsahraei et al. 2013; Sheikhlou et al. 2017). Nevertheless, it was less than the estimates for the Iranian Karakul, Iran-Black and Baluchi sheep (Bahri et al. 2015; Mokhtari et al., 2014; Tahmoorespur and Sheikhlou 2011). This differences in INBREEDING rate could be attributed to the differences in the pedigree completeness of animals and also to the low proportion of matings between relatives and better control of INBREEDING in Moghani sheep. Table 3 shows the least square means for body weight traits in different INBREEDING classes of animals. The mean BW and 3MW of animals in the second class was lower than non-inbred animals (P<0. 05). However, means of the BW and 3MW of animals in third class were higher than the second class. In other words, some of the heavy animals were between the highly inbred animals. Similar to our results, Prod’ Homme and Lauvergne (1993) reported increased prolificacy with increasing INBREEDING. They concluded that the positive effects of selection and improved management on prolificacy were larger than the negative effect of INBREEDING. However, it should be kept in mind that the low proportion of animals in the third class of INBREEDING in this study may also have contributed to these results. According to the Table 3, means of the 6MW, 9MW and YW have decreased with increasing in INBREEDING, but the differences between INBREEDING classes were not significant. The regression coefficients of BW, 3MW, 6MW, 9MW and YW on INBREEDING were 0. 006,-0. 023,-0. 051,-0. 017 and-0. 119 and on INDIVIDUAL increase in INBREEDING were 0. 022,-0. 044,-0. 185,-0. 111 and-0. 326, respectively and were not significant (P>0. 05). Converting INDIVIDUAL increase in INBREEDING coefficients to the equivalent INBREEDING for an animal with an average depth of pedigree resulted in INBREEDING depression of 6,-13,-55,-33, and-96 gram in BW, 3MW, 6MW, 9MW and YW, respectively. Conclusion: Considering the results obtained in this study, large proportion of animals in this flock with good pedigree completeness were inbred. Thus, implementation of methods to control INBREEDING in this flock are suggested to achieve desired genetic gain with minimum loos of genetic diversity in the future. It seems that preweaning traits (BW and 3MW) is more affected by INBREEDING rather than other growth traits in this breed. In this study the pattern of the changes in INBREEDING depression due to using INDIVIDUAL increase in INBREEDING in the model were not the same across the different body weight traits.

Background and objectives: INBREEDING is the increase in homozygosity of offspring resulted from mating between related animals or animals that have common ancestors. The main effect of INBREEDING is decline in performance of inbred animals known as INBREEDING depression. The magnitude of INBREEDING depression is not the same across the various traits and populations. Recent studies revealed that INBREEDING depression also shows variation among founders within a population. Variability of INBREEDING depression arises when distribution of deleterious recessive alleles among founders are not equal. Furthermore, the detrimental effects of INBREEDING can be reduced if deleterious recessive alleles were removed (purged) by selection against homozygotes in earlier generations. Estimating partial and ancestral INBREEDING coefficients makes it possible to assess the balance of distribution of recessive alleles among founders and incidence of purging of deleterious alleles in population. The objective of this study was to estimate Wright INBREEDING, partial INBREEDING, Ballou ancestral INBREEDING and Kalinowski ancestral INBREEDING coefficients in the Karakul sheep nucleus breeding flock. Materials and methods: In this study the pedigree data file of Karakul sheep nucleous breeding flock containing 7477 pedigree records collected during 1989-2014 was used to estimate Wright INBREEDING, partial INBREEDING and ancestral INBREEDING coefficients of animals. Pedigree completeness index was calculated to evaluate the quality of pedigree. Animals that born in the last four years of the pedigree with pedigree completeness index of greater than 0. 6 was considered as a reference population to decompose INBREEDING to partial INBREEDING arises from founders. Ballou ancestral INBREEDING of all animals was estimated. Also, INBREEDING coefficients of animals were decomposed to the New and Kalinowski ancestral INBREEDING. Results: The mean of Wright INBREEDING coefficients of animals in all population and reference population were 0. 85 and 1. 36, respectively. A total of 108 of 280 founder animals (38%) have a positive contribution to the INBREEDING of the reference population. Mean and standard deviation of the partial INBREEDING coefficients of these 108 animals were 5. 19 and 7. 37%, respectively. The 10 and 25 founders contributing the most to INBREEDING explained a large part of the INBREEDING of the reference population (i. e., 42 and 66%, respectively). Mean Ballou ancestral INBREEDING of the whole and reference population were 1. 17 and 2. 12, respectively. Most of the animals in the population have positive Ballou ancestral INBREEDING. Kalinowski ancestral INBREEDING of animals was low and its mean was 0. 07% in the population. Ancestral INBREEDING in this population was in accordance with Ballou definition of ancestral INBREEDING. Correlation of wright INBREEDING coefficient with Ballou ancestral INBREEDING, Kalinowski ancestral INBREEDING and new INBREEDING coefficients was 0. 1, 0. 37 and 0. 99, respectively. Conclusion: Based on the results of this study, Ballou ancestral INBREEDING coefficients of animals in this flock has increasing trend which can lead to purging of deleterious alleles in this population. Therefore, for assessing the incidence of purging of deleterious alleles in this population, estimating of the effects of ancestral INBREEDING on reproductive and production traits are suggested. Also, the estimated partial INBREEDING coefficients of animals can be used to determine the contribution of each founder to observed INBREEDING depression. On the other hand, estimated partial INBREEDING coefficients can help to detect founders carrying deleterious alleles. Then, these information could be used in mating programs, so that, new born lambs have a less partial INBREEDING arises from carrier animals or those animals which have greater contribution to INBREEDING depression.

The objective of this study was to determine the INBREEDING depression on growth traits in Moghani sheep. Pedigree information of 8836 animals collected during the years of 1987 to 2006 by Moghani Breed Center in Jafar Abad Moghan, were used for analysis. The base population year was 1988. Analysis of the records was performed by ASReml software. INBREEDING depression was estimated as the regression of performance on the INDIVIDUAL INBREEDING coefficients via fitting an animal model. The mean INBREEDING for all animals, females and males, were 0.500, 0.515 and 0.484 %, respectively. Totally, 24.22 % of all the animals were inbred. The mean of INBREEDING for inbreed animals was 2.062 %. The rate of increased INBREEDING per year for all animals was 0.05%. The INBREEDING depression for body weight traits at birth, 3, 6, 9 and 12 months of age was, respectively, -0.007, - 0.291, - 0.026, -0.018 and -0.041 kg, per 1% increase in INDIVIDUAL coefficient.

The aim of this study was to estimate amount of INBREEDING coefficient in Shal sheep and its impact on growth performance. Pedigree information and body weight at different ages (birth weight, 3 month weight, 6 month weight, 9 month weight and 12 month weight) were used from 6692 lambs from 90 rams and 1007 ewes. Data were collected on Ghazvin sheep breeding station during 1997-2013. Estimation of INBREEDING coefficient was done by CFC program and quantifying the INDIVIDUAL INBREEDING regression of traits was run by wombat software. Number of inbred animals at pedigree was 1616 lambs, equal to 24.15% of total population. The average of INBREEDING coefficient on whole population and inbred population were 1.51% and 6.28%, respectively. Regression coefficients per 1% INBREEDING for birth weight, 3 month weight, 6 month weight, 9 month weight and 12 months weight were estimated as -0.001, -0.017, -0.005, -0.019 and -0.019 kg, respectively. The highest INBREEDING coefficient was 31.25% and most of inbred animals had INBREEDING coefficients lower than 5%. These results confirmed the low level of INBREEDING in the population. Annual trend of INBREEDING coefficient on population average was 0.07 and non significant statistically. Applying a designed mating system like cross-breeding could be a suitable method to avoid INBREEDING depression.

A pedigree file consisting of 5860 INDIVIDUALs, 167 sires and 1582 dams collected at Makooei sheep breeding station (MSBS) during a period of 24 years (1990 to 2013) was used to calculate the INBREEDING coefficients to reveal any probable effects of INBREEDING (F) on the studied traits. The studied traits were classified to the five main groups including body weight, Kleiber ratio, body measurements, greasy fleece weight and reproductive traits. The INBREEDING coefficient among the INDIVIDUALs ranged from 0 to 25% with an average of 0.33%, and ranged from 0 to 25% among the ewes with an average of 0.21%. Fluctuations in INDIVIDUAL and maternal INBREEDING were observed in the period under study. The average generation interval was calculated as 3.6 years. The effective population size of the flock was 51.8 animals. The rate of INBREEDING was 0.08% per year and 0.53% per generation. Six different models were applied and likelihood ratio test (LRT) was used to select the appropriate model. Based on the LRT, model II was selected as appropriate model for growth, greasy fleece weight at 6 months of age and kleiber ratio traits. The traits related to the live body weight were affected negatively (P<0.001) by the quadratic INDIVIDUAL F. The linear INDIVIDUAL regression coefficient of the Kleiber ratio was estimated significantly (P<0.01) as 0.001, as well the linear maternal INBREEDING regression was estimated significantly (P<0.05) as 0.0002. In general, body measurements were affected negatively by the quadratic effects of INBREEDING (both INDIVIDUAL and maternal) and positively by the linear effects of INBREEDING. The reproductive traits were studied based on ewe INBREEDING coefficient. Among the reproductive traits, the quadratic regression coefficient of conception rate was estimated significantly (P<0.05) as -0.22. Quadratic regression coefficient of litter mean weight per lamb born were estimated significantly (P<0.01) as -0.63 per 0.01 change in the ewe INBREEDING coefficient. Therefore, INBREEDING should be avoided, except for purposes of genetic breeding whose main objective is the fixation of certain alleles in the population.

INBREEDING causes harmful effects on different characteristics of honey bee colonies such as honey production. In order to study of INBREEDING rate in apiaries of Miyaneh region, %5 of modern hives were choosed and scales and standard Langerstrot combs were used according to Rotner method. Bee population was recorded and free of brood cells were considered as INBREEDING index. Honey production was also measured by weighting the hives. INBREEDING rate was estimated as 15.05%. results showed that there were no significant differences between INBREEDING rate of several bee populations in Miyaneh region. INBREEDING percent was 9.22%, 10.93% and 23.48% for Kandowan, Torkmanchai and Kaghazkonan areas, respectively. Mean honey production per hive was also 11.9 kg. According to this study there were significant negative relationship between INBREEDING and honey production (r=-0.57, P=0.039) in apiaries of Miyaneh region of Iran.