Raeini Cashmere Research Articles

Genetic analysis of parent-of-origin effects on growth traits and yearling greasy fleece weight in Raeini Cashmere goat

Pedigree on 7253 individuals and data information on growth traits and greasy yearling fleece weight collected from 1979 to 2013 at the Breeding Station of Raeini Cashmere goat, south-east of Iran, were used for genetic analysis of parent of origin effects for these traits using a gametic relationship matrix. The studied traits included birth weight (BW; 4747 records), weaning weight (WW; 3268 records), six months weight (6 MW; 2855 records), nine months weight (9 MW; 1407 records), yearling weight (YW; 1013 records), and yearling greasy fleece weight (YFW; 1272 records). Models including or excluding imprinting (maternal and paternal) effects were compared by applying Akaike Information Criterion (AIC). Paternal imprinting effects did not influence any of the studied traits. Maternal imprinting effects explained 9%, 6%, 9%, 18%, and 6% of phenotypic variances for WW, 6 MW, 9 MW, YW, and YFW, respectively. By including the maternal imprinting effects in the model used for genetic analysis, direct heritability estimates for WW (from 0.04 to 0.01), 9 MW (0.24–0.15), YW (from 0.31 to 0.14), and YFW (0.18–0.09) were decreased, implying a considerable proportion of the maternal imprinting effects for these traits may overlap with direct additive genetic effects. BW did not influence by imprinting effects. Strong maternal imprinting correlations among body weights at different ages (except for BW) showed that WW, 6 MW, 9 MW, and YW share similar genes with maternally imprinted effects. It means that the imprinting effects of genes are not limited to a specific stage of life and can be active in different stages of growth. Maternal imprinting correlation estimates between YFW and other traits were not statistically significant. Therefore, imprinting effects may be crucial for the genetically evaluating of these traits in the Raeini Cashmere goat.

GENETIC DIVERSITY OF LEPTIN GENE INTRON 2 IN WILD AND NATIVE AND EXOTIC GOAT BREEDS IN IRAN

The aim of this study was to investigate the intron 2 of leptin gene polymorphism in wild, native and exotic goat breeds in Iran using PCR-RFLP. Blood samples were collected from 14 wild and domestic goat breeds including (Cashmere Abadeh, Torki-Ghashghaei, Naeini, Robati, Nadoushani, Adani, Shahrbabaki, Birjandi, China goat, Sannen, Pakistani, Raeini cashmere, Najdi and Wild goat) and then the genomic DNA was extracted. A 422bp fragment from intron 2 of the leptin gene was amplified. PCR products were digested by Sau3AI restriction enzyme and were separated and visualized on the agarose gel. Three genotypes including MM, Mm and mm with genotype frequency of 94%, 1% and 5%, respectively, were observed in the studied populations. The number of observed alleles, number of the effective alleles, Nei’s Index and Shanon’s Index were 2, 1.10, 0.09 and 0.19, respectively. The studied populations were not found to be in a Hardy-Weinberg equilibrium. Our investigation demonstrated that MM genotype and M allele had a very high frequency (0.94 and 0.95, respectively) in Iranian goats. Hence, it can be concluded that this finding can provide basis for selection when considering evolution and differentiation among breeds, however further studies should be carried out on a larger population of different domestic and wild breeds to verify the final conclusions.

Genetic and phenotypic aspects of early reproductive performance in Raeini Cashmere goats.

This study used pedigree information and data collected from 1979 to 2012 at the Raeini Cashmere goat breeding station, located in Baft City in Kerman Province in southeastern Iran. Genetic and phenotypic parameters for early reproductive traits of breeding does, including total numbers of kids born at first kidding (LSB1), total numbers of kids weaned at first kidding (LSW1), total birth weight of all kids born at first kidding (LWB1), total weaning weight of all kids weaned at first kidding (LWW1), and age at first kidding (AFK), were estimated using a Bayesian approach via Gibbs sampling. Posterior means for heritability estimates of LSB1, LSW1, LWB1, LWW1, and AFK were statistically significant, with values of 0.12, 0.23, 0.17, 0.15, and 0.46, respectively. Low-to-moderate additive genetic variation was present for the studied reproductive traits. Estimated genetic correlations among LSB1, LSW1, LWB1, and LWW1 were statistically significant and ranged from 0.12 between LWB1 and LWW1 to 0.72 between LSB1 and LSW1. Corresponding phenotypic correlation estimates were also statistically significant and ranged from 0.04 between LWB1 and LWW1 to 0.55 between LSB1 and LSW1. Posterior means of genetic and phenotypic correlations between AFK and other studied traits were statistically significant only for LSB1 and LWB1. For LSB1, LSW1, LWB1, and LWW1, we conclude that genetic and phenotypic improvement in any of these traits in Raeini Cashmere does would favorably influence all of the other traits. However, does that first kidded at younger ages have smaller litters at birth and lower litter birth weights at their first parity.

The estimation of genetic parameters for growth curve traits in Raeini Cashmere goat described by Gompertz model

The objectives of this study were to describe growth curve of Raeini Cashmere goat applying the Gompertz growth model and genetic evaluation of growth curve-related traits including model parameters of A, B and K, inflection age (IA) and inflection weight (IW) under animal model. The data used in this study, collected in Raeini Cashmere goat breeding station from 1997 to 2009 and were included 12,831 body weights records measured at birth, weaning, 6-months of age, 9-month of age and yearling of age. The Pearson’s correlation coefficient between observed and predicted body weights was 0.98, which means that Gompertz model adequately described the growth curve in Raeini Cashmere goat. The estimated value for growth curve parameters of A, B and K were 17.97, 1.97 and 0.017, respectively. The weight and age at point of inflection were 6.63 kg and 52.94 days, respectively. Direct heritability estimates for A, B, K, IA and IW were low values of 0.14, 0.10, 0.03, 0.14 and 0.14, respectively. Low estimated values for direct heritability of the studied growth curve traits in Raeini Cashmere goat indicated that direct selection for these traits may not be useful in terms of achieving genetic change. Direct genetic correlations ranged from −0.76 (K-IW) to 0.98 (A-IW). Phenotypic correlation estimates were generally lower than the direct genetic ones and ranged from −0.30 (K-IW) to 0.69 (A-B and B-IA). IA and IW had high positive phenotypic (0.86) and genetic (0.99) correlations, implying IA and IW were highly correlated in terms of phenotypic and genetic effects. The studied growth curve parameters of Raeini Cashmere goat have shown low levels of additive genetic variation.

The application of recursive multivariate model for genetic evaluation of early growth traits in Raeini Chasmere goat: A comparison with standard multivariate model

Data collected on 2638 kids originated from 1305 dams and 197 sires during 1979 to 2012 in Raeini Cashmere goat breeding station located in Baft, Kerman province, south-eastern part of Iran, on body weights of 2638 Raeini Cashmere kids at birth (BW), at weaning (WW) and at six-month age (6 MW) were used to adopt a fully recursive multivariate model considering causal effects from BW on WW and on 6 MW and from WW on 6 MW. The adopted recursive multivariate model (RMM) was compared with a standard multivariate mixed model (SMM), in which causal relationships were ignored, in terms of deviance information criterion (DIC), predictive ability and the estimates of genetic and phenotypic parameters. Preliminary analyses revealed that the importance of direct additive genetic, maternal permanent environmental and temporary environmental effects for genetic evaluation of all the studied traits. Maternal additive genetic effects were only influencing on BW. Model comparisons via DIC revealed the plausibility of RMM over SMM; DIC value obtained by fitting RMM (-15,218.76) was lower than that of obtained under SMM (21,654.92). For BW, lower mean square of error (MSE) and higher Pearson's correlation coefficient between the observed and predicted values (r(y,y^)) were obtained under SMM but in the case of WW and 6 MW lower MSE and higher r(y,y^) were obtained under RMM. The causal effects of BW on WW and on 6 MW and that of WW on 6 MW were 1.94 kg, 2.48 kg and 1.03 kg, respectively. The estimates of direct heritability, maternal heritability (for BW) and ratio of permanent and / or temporary environmental variances to phenotypic variance were not significantly affected by model fitted (SMM and RMM). Direct additive genetic correlations of BW-WW and BW-6 MW were not statistically significant under SMM (95% HPD interval included zero) but the corresponding estimates under RMM were significant (99% HPD interval did not include zero) values of 0.28 and 0.84, respectively; implying that genes associated with BW also increase WW and 6 MW in Raeini Cashmere goat. Direct genetic correlation estimate for WW-6 MW were 0.88 (under SMM) and 0.29 (under RMM). Generally, RMMs perform better than SMMs and may provide a better explanation to biological relationships among the studied traits.

Possibility of modifying the growth trajectory in Raeini Cashmere goat.

The objective of this study was to investigate the possibility of modifying the growth trajectory in Raeini Cashmere goat breed. In total, 13,193 records on live body weight collected from 4788 Raeini Cashmere goats were used. According to Akanke's information criterion (AIC), the sing-trait random regression model included fourth-order Legendre polynomial for direct and maternal genetic effect; maternal and individual permanent environmental effect was the best model for estimating (co)variance components. The matrices of eigenvectors for (co)variances between random regression coefficients of direct additive genetic were used to calculate eigenfunctions, and different eigenvector indices were also constructed. The obtained results showed that the first eigenvalue explained 79.90% of total genetic variance. Therefore, changing the body weights applying the first eigenfunction will be obtained rapidly. Selection based on the first eigenvector will cause favorable positive genetic gains for all body weight considered from birth to 12months of age. For modifying the growth trajectory in Raeini Cashmere goat, the selection should be based on the second eigenfunction. The second eigenvalue accounted for 14.41% of total genetic variance for body weights that is low in comparison with genetic variance explained by the first eigenvalue. The complex patterns of genetic change in growth trajectory observed under the third and fourth eigenfunction and low amount of genetic variance explained by the third and fourth eigenvalues.

Implementation of a cashmere goat breeding program amongst nomads in Southern Iran

A breeding program to improve income from Raeini cashmere herds run by nomads in Southern Iran was implemented. Eight nomads agreed on improving fleece weight, body weight and down yield while reducing cashmere fibre diameter of white coated goats. Economic weights were calculated to define a breeding objective. Each nomad established a breeding nucleus selecting visually his best 40 does and two bucks from about 250 goats. Nomads used different systems to ensure separate mating of nucleus and general herd animals. Nomads were also able to identify the progeny of each buck. Nucleus progenies were recorded for weaning weight and fleece weight. Fleece samples were collected for analyses of down yield and down fibre diameter. General herd male progeny was castrated. Formal selection indices were used to select nucleus male replacements. To construct the indices phenotypic and genetic parameters were taken from project data and published figures. Accuracy of indices ranged 0.47 to 0.66 depending on the traits included. The inferior buck based on progeny index average was replaced by the best young buck available. Other high ranked young bucks were used in the general herd. The breeding program is in its fourth cycle and favourable selection differentials were confirmed for selected bucks in all traits of interests, in particular for down weight and down diameter, 62g and −0.5μm, respectively. The expected benefit of the program is about 4.0 USD accumulating per goat and per year. Fleece testing is an issue since the region lacks a fleece testing service. If fleece sampling is discontinued the expected benefit reduces to about 2.8 USD per goat and per year. Circular use of bucks to control inbreeding and participation of additional nomad families are planned for the future. This experience shows that a participatory breeding program can be successfully implemented under nomadic conditions through intensive collaboration of nomad herders, regional extension officers and scientists.

Observations on the efficiency of using different cashmere combs

The effect of using small or large cashmere combs on cashmere harvest, cashmere quality and combing time was studied on Raeini cashmere goats in nomadic goat breeding systems of the Iranian province of Kerman. Two groups of 20 goats of different ages were combed with either a large or a small comb, three times with intervals of 2 weeks in early spring when natural fiber shedding has started. Combed cashmere weight, duration of combing, fiber diameter, and down yield were measured. A sample of combed cashmere was analyzed using a Laserscan instrument. A general linear model including type of comb, stage of combing and age of goat was fitted to analyze the data. Small combs collect more cashmere (31.0 vs. 21.7g, P<0.01) than large combs without affecting down yield or down fiber diameter (P>0.05) but combing time is higher (3.75 vs. 2.79min, P<0.01). In the first two combing sessions much more cashmere was obtained than in the last (28.1, 32.0 and 19.0g, respectively, P<0.01), but the weight of total combed cashmere was much less than typical shorn fleece weights. Combing can be justified only if a considerable price premium can be obtained from selling combed cashmere instead of selling shorn cashmere, or if the combed cashmere is used to add value on-farm. If this is the case, small combs with short rods are preferable since more cashmere can be collected without affecting its quality.

Effect of sex and rearing system on the quality and mineral content of fiber from raeini cashmere goats

The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 μm, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).

Genetic parameter estimates for growth traits and prolificacy in Raeini Cashmere goats

The main objectives of this study were to estimate genetic and phenotypic parameters for growth traits and prolificacy in the Raeini Cashmere goat. Traits included, birth weight (BWT), weaning weight (WWT), 6-month weight (6WT), 9-month weight (9WT), 12-month weight (12WT), average daily gain from birth to weaning (ADG1), average daily gain from weaning to 6WT (ADG2), average daily gain from 6WT to 12WT (ADG3), survival rate (SR), litter size at birth (LSB) and litter size at weaning (LSW) and total litter weight at birth (LWB). Data were collected over a period of 28 years (1982-2009) at the experimental breeding station of Raeini goat, southeast of Iran. Genetic parameters were estimated with univariate models using restricted maximum likelihood (REML) procedures. In addition to an animal model, sire and threshold models, using a logit link function, were used for analyses of SR. Age of dam, birth of type, sex and of kidding had significant influence (p < 0.05 or 0.01) all the traits. Direct heritability estimates were low for prolificacy traits (0.04 ± 0.01 for LSB, 0.09 ± 0.02 for LSW, 0.16 ± 0.02 for LWB and 0.05 ± 0.02 for SR) and average daily gain (0.12 ± 0.03 for ADG1, 0.08 ± 0.02 for ADG2, and 0.07 ± 0.03 for ADG3) to moderate for production traits (0.22 ± 0.02 for BWT, 0.25 ± 0.02 for WWT, 0.29 ± 0.04 for 6WT, 0.30 ± 0.02 for 9WT, 0.32 ± 0.05 for 12WT). The estimates for the maternal additive genetic variance ratios were lower than direct heritability for BWT (0.17 ± 0.03) and WWT (0.07 ± 0.02).

Cashmere quality of Raeini goats kept by nomads in Iran

The income of the nomads in Kerman Province depends mainly on Raeini goats that produce meat, milk and cashmere. This paper assesses the cashmere quality and its variation in Raeini herds to determine the scope for improvement. In April 2010 fleece weights (FW) and midside fleece samples were taken from a total of 686 male and female cashmere goats of 1, 2 and 3 years of age belonging to 29 herds. The herds were randomly chosen in the summer grazing area of nomads within 20km of the city of Baft, province of Kerman, South of Iran, the main cashmere producing area in Iran. Cashmere yield (CY) was determined from the weight of dehaired cashmere to weight of shorn fiber. Cashmere fibers were analyzed using an OFDA instrument. A general mixed linear model including sex, age and sex by age interaction as fixed effects and herd as random effect was used to analyze the data and measure the relationships between different cashmere characteristics and fleece attributes. The overall means±standard deviations were for fleece weights (FW) 507±183g, cashmere yield (CY) 56.5±12.2%, mean fiber diameter (MFD) 19.7±1.5μm, fiber diameter standard deviation (FDSD) 4.5±0.6μm, fiber curvature (FC) 62.9±8.5°/mm and staple length (SL) 54.2±7.0mm, respectively. Herd effect was significant for all traits except for SL and sex by age effect was only significant for MFD. One year old males and females had finer cashmere than older goats. FW and FDSD were higher in males and CY and FC was higher in young animals. Pearson correlation between MFD and FC, FDSD and MFD, MFD and FW was −0.647, 0.399 and 0.211 respectively. Raeini cashmere is white, has an excellent SL and FC but is relatively coarse. Given the differences between and within herds there seems to be substantial scope to improve the commercial value of Raeini cashmere.

Environmental Factors Affecting Fleece Traits in Raeini Cashmere Goat

The objective of this study was to evaluate some environmental factors (sex, age and management system) on fibrecharacteristics of Raeini Cashmere goats in Baft stations (BS) and of Raeini Cashmere goats raised in nomadic conditions (NC) as commercial flocks. Fiber samples including cashmere and hair were taken from 150 and 120 Raeini Cashmere goats (aged 1-8 years old) from BS and NC, respectively. The Fleece traits measured included staple length (SL), percentage of cashmere in fleece (C), percentage of guard hair in fleece (H), cashmere's mean fiber diameter (CMFD) and the coefficient of variation of cashmere's fiber diameter (CVFD). Mean SL, C, H, CMFD and CVFD in BS were 6.35 ±0.1 cm, 66.51± 0.72 %, 33.5 ± 0.72 %, 20.19 ±0.11 micron and 19.57± 0.21% and thosein NC were 5.62 ± 0.1 cm, 69.06 ± 0.74 %, 30.94 ±0.74 %, 19.53±0.15 micron and 17.88 ± 0.19 %, respectively. There were significant differences (P&lt;0.05) between the two production management systems for all traits investigated. The value for C was significantly higher in males than females (P&lt;0.05). The results showed that the fleece traits were affected by age. However, the effect of age on these traits was not the same. Significant phenotypic correlations were found between SL and CMFD (0.16) and between SL and CVFD (0.13). The results of this study indicated that the fixed effects of age, sex and management systems as well as the relationship between fleece traits should be considered in the Raeini Cashmere goat breeding programs.

The effects of nutrition and age on characteristics of fibers Raeini Cashmere goat

Traditionally goats are indeed important in Iran especially for milk and fibers. This country has nearly 5000000 cashmere producing goat, which produce approximately 1500 metric ton of raw cashmere. So research on environmental factors which have effect on cashmere production, is very vital to economy of the country. Raeini breed is the most productive Cashmere goat in Iran. However, There are no detailed descriptions of the effects of nutrition on cashmere characteristics in Raeini goat. There is some debate on the effects of nutrition on cashmere growth. In some studies cashmere growth does not respond to increased feed intake above maintenance. While some reviewers have concluded that nutrition does influence cashmere growth (McGregor, 1998). The objective of this study was to describe the effects of feeding level on the cashmere growth of Raeini female goats at two different ages.

Inbreeding and its effects on some economic traits in Raeini cashmere goats

The Breeding Center of Raeini (BCR) cashmere goats was established in 1965 in Kerman province, with a base population of 120, 8 and 42 does, bucks, and kids respectively. Some new animals have been introduced to the BCR population in some periods of time, and selected males have been sold out to the local breeders each year. Animals have been selected based on their phenotypic performance for fleece weight (FW) and fleece color (FC-white), and body weight (BW). Mating system has been planned based on non-relative mating, but some relative mating has been occurred. Inbreeding depression is one of the most important empact of having inbreeding in a population (Miglior and Burnside 1995). A decrease of 0.8% in fiber length and 6.3% in longevity per 10% increase of inbreeding coefficient in cashmere goats has been reported (Deb 1998). The objective of this study was to estimate the animals inbreeding coefficient and to explore the impact of inbreeding on some economic traits in Raeini cashmere goats.