Coarse Wool Sheep Research Articles

Genetic markers in sheep breeding

The priority direction in developing domestic sheep breeding is the creation of new and improved breeding forms that combine high meat and wool productivity rates with good adaptive qualities to breeding conditions. In Russia, 404.2 thousand heads of coarse-wool sheep breeds and 21.2 thousand heads of semi-coarse-wool sheep are concentrated on breeding farms. Compared to 2000, the number of breeding animals increased by 5.0 times, while the yield of lambs for slaughter per 100 breeding queens increased by 5.7 times. One way to increase the selection and breeding work with breeds is to search and use genetic markers of productivity and vitality. The work aimed to summarise and analyse information about the genetic polymorphism of genes associated with traits of productivity and disease resistance in different breeds of sheep. The results of studies of polymorphic variants of genes related to the growth energy of young animals, wool quality and meat productivity in sheep are presented. The calpastatin (CAST) gene is described, which is associated with meat productivity and tenderness of meat the KRT (keratins) gene - with wool productivity and wool quality, the growth hormone gene GH and the differential growth factor gene GDF9 - with the regulation of growth and development, reproductive qualities and meat production, sheep productivity. In most studies, the predominant genotype in all breeds is CASTMM. The frequency of genotypes for the KRT and GH genes in breeds of different directions of productivity varies significantly. The relationship of genotypes CAST, GН, and GDF9 with economically valuable traits is described, making it possible to consider their genetic markers.

Two mutations at KRT74 and EDAR synergistically drive the fine-wool production in Chinese sheep

IntroductionFine-wool sheep are the most common breed used by the wool industry worldwide. Fine-wool sheep have over a three-fold higher follicle density and a 50% smaller fiber diameter than coarse-wool sheep. ObjectivesThis study aims to clarify the underlying genetic basis for the denser and finer wool phenotype in fine-wool breeds. MethodWhole-genome sequences of 140 samples, Ovine HD630K SNP array data of 385 samples, including fine, semi-fine, and coarse wool sheep, as well as skin transcriptomes of nine samples were integrated for genomic selection signature analysis. ResultsTwo loci at keratin 74 (KRT74) and ectodysplasin receptor (EDAR) were revealed. Fine-scale analysis in 250 fine/semi-fine and 198 coarse wool sheep narrowed this association to one C/A missense variant of KRT74 (OAR3:133,486,008, P = 1.02E-67) and one T/C SNP in the regulatory region upstream of EDAR (OAR3:61,927,840, P = 2.50E-43). Cellular over-expression and ovine skin section staining assays confirmed that C-KRT74 activated the KRT74 protein and specifically enlarged cell size at the Huxley’s layer of the inner root sheath (P < 0.01). This structure enhancement shapes the growing hair shaft into the finer wool than the wild type. Luciferase assays validated that the C-to-T mutation upregulated EDAR mRNA expression via a newly created SOX2 binding site and potentially led to the formation of more hair placodes. ConclusionsTwo functional mutations driving finer and denser wool production were characterized and offered new targets for genetic breeding during wool sheep selection. This study not only provides a theoretical basis for future selection of fine wool sheep breeds but also contributes to improving the value of wool commodities.

EXTINCT FARM ANIMALS’ BREEDS OF UKRAINE

The industrialization since the beginning of the previous century led to the loss of a significant number of breeds. But it should be remembered, that the disappearance of a breed is not only the disappearance of an important unit that supplemented the uniqueness of a specific landscape, met the needs of a certain category of people who lived in this territory, performed certain rituals associated with traditions and territory, evolved with and complemented a certain culture and nation, but as well the breed – it is the genes, which were not revealed at that time, but in the future could provide people with the development of the latest technologies with new products, a new type of knowledge, skills and useful peculiarities.&#x0D; The analysis of the literal source base of the past centuries confirms the disappearance of Polish, Red Smilyan, Ukrainian White-Backed, Black-and-White Podilian in cattle breeding, in sheep breeding – 9 breeds (Walahian, Pirni, Reshetilivska, Chushka, Mazayev Merino, Malich, Hutsulian, Chuntuk), in horse breeding – Streletsky, Germano-Bessarabian, Nogai breeds and Tarpan. 3 breeding populations have disappeared in pig breeding.&#x0D; Disappeared in cattle breeding: the Polissian breed of cattle, which was widespread in the 19th and early 20th centuries on a large territory of Polissia (in 1926, on the right-bank Polissia, it numbered about 35.000 heads). By origin, the Polissian cattle were admitted a descendant of the ancient race that lived in Polissia since ancient times.&#x0D; The animals were exceptionally hardy, resistant to diseases typical for the region, and had a certain productivity even in difficult conditions of unsatisfactory keeping.&#x0D; The Red Smilyan breed of the beginning of the 20th century was spread in the area of the town of Smila, "from north to south along the railway through the town of Smila all the way to Horodyshche and Chhyrynsky district. This breed was "a branch of red steppe cattle, which, like Grey Ukrainian cattle, belonged to the group of steppe cattle." So, it would be interesting to investigate it as well.&#x0D; At the beginning of the last century, the different varieties of spotted cattle of Podillia were spread over almost the entire territory of the Vinnytsia region (except for the northern part). Researchers estimate the presence of this livestock at the level of 100.000 heads at the beginning of the last century. This group included Black-and-White Podilian and Ukrainian White-Backed breeds.&#x0D; Sheep breeding. Coarse-wool sheep have been bred on the territory of Ukraine for a long time, especially Reshetilivska and Sokilian sheep. In the literature, there is also information about the breeding of Wallahian sheep.&#x0D; Horse breeding. Research in recent years suggests a high probability of domestication of horses in the territory of the steppes of Ukraine, so it would be especially interesting to study the behavior, characteristics, and variety of products of ancient horses of Ukrainian origin. However, this is no longer possible on at least 3 breeds of horses: Striletska, Germano-Bessarabian, Nogai and Tarpan. In addition, there is evidence that in Ukraine in the 17th century a breed of striped (tarantoid) horses was widespread. Ethnological studies also report on the existence of Steppe Ukrainian horse, bred in Zaporizhzhia, and Boykivian (boyki, perevinniki) horse breed in the Carpathians. The Ukrainian breed of horses became the basis for the formation of the Black Sea breed in the Kuban after the Cossacks of Zaporizhzhya Sich were resettled there in the 19th century.&#x0D; Pig breeding. According to the National Coordinator of Genetic Resources from Ukraine in FAO until 2014, I.V. Guzev, three breed groups of pigs and one local population (European short-eared pig) have disappeared in Ukraine. According to ethnographers, Ukrainian black and brown breeds have long been predominant on the territory of Ukraine. So, it was the Ukrainian sub-population of European group of pigs. This group as well was characterized with yellowish, brown or white, mixed with black bristle color. There were as well individuals of gray or white color with black spots, small fangs were visible.

A Search for Eurasian Sheep Relationships: Genomic Assessment of the Autochthonous Sheep Breeds in Russia and the Persian Plateau

Genomic assessment of local sheep breeds is relevant to the reconstruction of post-domestication migrations and to filling in gaps in the developmental history and contemporary phylogeographic-differentiation patterns in Eurasia. In this study, we aimed to reveal possible genetic relationships between local sheep breeds in Russia and the Persian Highlands (Iran) based on high-density SNP genotypes. All samples (n = 395) from 11 Iranian and 10 Russian sheep breeds were genotyped by using the Ovine Infinium HD BeadChip (Illumina, San Diego, CA, USA). Principal Component Analysis, maximum-likelihood assessment, and Neighbor-Net graph analysis demonstrated a clear differentiation between Russian sheep breeds of European ancestry from the Iranian local cluster and Russian breeds of Asian origin. Admixture analysis revealed a shared ancestral background, which was detected in several Iranian-local and Russian-local fat-tailed coarse-wool sheep breeds. Our findings contribute to a better understanding of the pattern of historic admixture, which is present in the genomes of many Eurasian sheep breeds.

Characteristics of the Edilbay sheep breed of the Republic of Kazakhstan

The article analyses material from sheep domestication to the present state. Data on the world’s leading countries, where sheep breeding is most intensively developed, are given. The largest sheep populations are concentrated in China, Australia, India and Sudan. There are 995 registered local sheep breeds, of which 100 are international cross-border sheep breeds. Many species are continually becoming extinct. Therefore, the problem of preserving the unique gene pool of aboriginal breeds is acute in many countries. More than 20 breeds of sheep are bred in Kazakhstan. Over the last ten years, the number of sheep in the Republic has been between 18.0-20.0 million. The most widespread sheep breeds are Edilbay, Kazakh Arkharmerinos and Kazakh Kurdish coarse-wool sheep. Sheep of the Edilbay breed are bred in 10 regions of Kazakhstan. Edilbay breed is adapted to breeding in areas of dry steppes, semi-desert and desert regions. The article gives a brief zootechnical characteristic of Edilbay sheep and describes the epizootic situation in the Republic of Kazakhstan. Particular attention is paid to changing the breeding strategy. In further breeding and pedigree work, the aim is to create a sheep population with reduced fat content. A plan has been outlined for comprehensive studies of the sheep gene pool and phenofund, including evaluating protein, carbohydrate, fat and mineral metabolism, chemical, physiological, cytogenetic, molecular-genetic, and other research methods. Water, soil, and feed will be monitored for heavy metals and macronutrients during the experimental work.

Породы овец в контексте исторического развития отрасли на Крымском полуострове

Abstract. To develop of sheep breeding in the selected region should be based on the most complete analysis of previous work with sheep breeds. This will allow to plan further stages in the industry. The purpose of the analysis was to study the origin, the main characteristics of sheep breeds on the Crimean Peninsula, their intensification and the purpose of their use on the basis of literary sources. The main research method is periodization, which allows us to analyze the breed composition of sheep in the studied time stages, which allows us to compare the features of the considered stages of the development of the industry on the peninsula. The results of the analysis indicate the fact that the sheep breeds in various historical periods of development of the Crimean Peninsula are an important element of sheep breeding described in the article. The fact that the coarse wool sheep breeding developed extensively and have been focused on getting from sheep's milk and mutton at the end of the XVIII century. Manufacturers in the XIX century on the production of fine wool accent give. Suitable types and breeds of sheep in the practice introduced are Electoral (sheep with superior wool), Electoral-and-Negretti, Negretti, Rambouillet and others. Production of sheep's milk and its products have occupied only peasant farms, where animals are were bred coarse wool and semi-fine wool breeds are Malych, Valachian and Tsigai. Sheep breeding industry develops intensively in the twentieth century in Crimea. Tsigai Breed sheep becomes of the planned. This breed is still the main on peninsula and the present time. The scientific novelty lies in the fact that for the first time a deep historical analysis of the evolution of sheep farming on the Crimean Peninsula since its entry into the Russian Empire at the end of the 18th century was carried out and recommendations for the further development of the industry were given.

Genome-wide DNA arrays profiling unravels the genetic structure of Iranian sheep and pattern of admixture with worldwide coarse-wool sheep breeds

Archaeological and genetic evidence show that sheep were originally domesticated in area around the North of Zagros mountains, North-west of Iran. The Persian plateau exhibits a variety of native sheep breeds with a common characteristic of coarse-wool production. Therefore, knowledge about the genetic structure and diversity of Iranian sheep and genetic connections with other sheep breeds is of great interest. To this end, we genotyped 154 samples from 11 sheep breeds distributed across Iran with the Ovine Infinium HD SNP 600 K BeadChip array, and analyzed this dataset combined with the retrieved data of 558 samples from 19 worldwide coarse-wool sheep breeds. The average genetic diversity ranged from 0.315 to 0.354, while the FST values ranged from 0.016 to 0.177 indicating a low differentiation of Iranian sheep. Analysis of molecular variance showed that 90.21 and 9.79% of the source of variation were related to differences within and between populations, respectively. Our results indicated that the coarse-wool sheep from Europe were clearly different from those of the Asia. Accordingly, the Asiatic mouflon was positioned between Asian and European countries. In addition, we found that the genetic background of Iranian sheep is present in sheep from China and Kyrgyzstan, as well as India. The revealed admixture patterns of the Iranian sheep and other coarse-wool sheep breeds probably resulted from the expansion of nomads and through the Silk Road trade network.

Dairy productivity ewes' karachai breed of sheep and its relation with living mass and vertical zoning of pastures

Milk production and live weight of queens in mountain meat-coarse-wool sheep breeding, as one of the main quantitative traits in postnatal ontogenesis, are more susceptible to the influence of paratypical factors, that is, they have a large “rate of reaction” to the conditions of feeding and maintenance.In order to resolve the question * how to select, what animals to leave for the tribe in the mountain meat coarse-wool sheep breeding *? We at OOO Dargan, a mountainous zone of the Kabardino-Balkarian Republic (KBR), according to the methodology, formed five groups of queens, with a class interval of 5 kg.It was found that the milk production of the queens had a certain relationship with their live weight, and was 32.4 kg in group V, which exceeds the same indicator of group IV by 1.4 kg; III - by 3.0; II - by 7.6; I - by 8.5 kg, the difference between IV and III groups is 0.6 kg.At 4 months of age, the rams of group V in live weight exceeded rams of groups IV and III by 0.7 and 0.4 kg, II - by 2.5 kg, I - by 5.3 kg, at 6 months of age - I at 7.9 kg, II - at 4.0 kg, III - 1.5 kg. There were no significant differences between IV and V groups - 0.7 kg.Along with this, it should be noted that with an increase in the vertical zoning of pastures above sea level (above sea level), with steep slopes, the higher milk production potential of large queens is leveled.The obtained research results indicate that in mountain meat and coarse-wool sheep breeding, selection for increasing the milk yield of ewes, in combination with the optimal live weight, is an effective method of increasing the live weight of young animals.

PSX-18 High-density genomic description of Russian native sheep breed of the Republic of Tyva

Abstract Tuva breed is the oldest native sheep breed in Russia with more than 2000 year-history and comes in third place by population size among coarse wool sheep. Tuva sheep produce high-quality meat as well as coarse wool to make traditional clothing in the Republic of Tyva. In present study, we aimed to evaluate genetic diversity and to establish genetic links of the Tuva breed with the other Russian coarse wool sheep to understand the origin and current status of this valuable livestock species. Twenty samples of Tuva were genotyped using Ovine Infinium® HD SNP BeadChip (Illumina, CA, USA). SNP-data were processed in PLINKv1.9, R package ‘diveRsity’ and SneP software. High-density SNP-genotypes of 10 coarse wool sheep breeds were used as comparison groups. Observed heterozygosity (Ho) and allelic richness (Ar) in Tuva breed were 0.336 and 1.884, respectively, and were practically equal to mean values estimated across all analyzed sheep breeds (Ho=0.335, Ar=1.884). All coarse wool breeds showed moderate heterozygote excess which was the highest in Tuva breed (1.6%). Effective population sizes estimated for three and five generations ago for Tuva breed (Ne3 =118 and Ne5 =179) were less than those in other breeds (Ne3 = 314 and Ne5 = 441 for Edilbai or Ne3 = 300 and Ne5 = 450 for Kalmyk) but not the lowest (Ne3 = 49 and Ne5 = 72 for Buubei). Values of historical effective population size estimated for 60 generations ago for Tuva breed was 1457 that was compatible with those obtained for other breeds (Ne60 from 586 for Buubei to 2634 for Kalmyk). Despite the obvious decrease in effective population size, levels of genetic diversity are not critical that would allow to develop programs to ensure preservation and sustainable development of Tuva breed. The study was funded by RSF No. 19-16-00070.

Identification of the Ovine Keratin-Associated Protein 2-1 Gene and Its Sequence Variation in Four Chinese Sheep Breeds.

Keratin-associated proteins are important components of wool fibers. The gene encoding the high-sulfur keratin-associated protein 2-1 has been described in humans, but it has not been described in sheep. A basic local alignment search tool nucleotide search of the Ovine Genome Assembly version 4.0 using a human keratin-associated protein 2-1 gene sequence revealed a 399-base pair open reading frame, which was clustered among nine previously identified keratin-associated protein genes on chromosome 11. Polymerase chain reaction–single strand conformation polymorphism analysis revealed four different banding patterns, with these representing four different sequences (A–D) in Chinese sheep breeds. These sequences had the highest similarity to human keratin-associated protein 2-1 gene, suggesting that they represent variants of ovine keratin-associated protein 2-1 gene. Nine single nucleotide variations were detected in the gene, including one non-synonymous nucleotide substitution. Differences in variant frequencies between fine-wool sheep breeds and coarse-wool sheep breeds were detected. The gene was found to be expressed in various tissues, with the highest expression level in skin, and moderate expression levels in heart and lung tissue. These results reveal that the ovine keratin-associated protein 2-1 gene is variable and suggest the gene might affect variation in mean fiber diameter.

Environmental Factors Affecting Genetic Variation in Coarse-Wool Sheep

Economic activities of the population living in the rural areas of the world is 70% dependent on traditional livestock production systems based on indigenous breeds. Consequently, it is very important to protect and preserve the heritage breeds of animals resistant to any diseases and better adapted to the changing environmental conditions. The effects of the natural environmental factors on the formation of the genetic structure in 24 coarse-wool breeds of sheep reared in nine countries of Europe and Asia have been studied. Genetic surveys of 20 microsatellite loci were carried out. The most significant environmental factors causing the genetic variation in the analyzed sheep breeds turned out to be the geographical latitude and the annual mean temperature. The genetic variation in the coarse-wool sheep breeds was generally higher at low geographical latitudes, which corresponds to the data obtained for the other animal species. Therefore, the protection of animal populations inhabiting the areas at the low geographical latitudes can contribute to a higher intraspecific diversity than the protection of the same number of populations distributed in the high latitude ranges. This fact should be especially considered when planning the programs to preserve the biodiversity of animals since the breeds of sheep reared near the centers of animal domestication have a higher genetic variation. Hence, they can serve as the source of genes contributing to adaptation under the conditions of global climate change.

Genetic factors affecting genetic variance in coarse-wool sheep

The life activity of the rural population in the world is 70% dependent on the traditional animal farming systems based on the domestic livestock breeds. Consequently, it is very important to preserve and enhance the local breeds of animals resistant to any diseases and better adapted to the changing environmental conditions. The environmental factors affecting the genetic structure in 24 coarse-wool breeds of sheep reared in 9 countries of Europe and Asia have been studied. The genetic surveys of twenty microsatellite loci were carried out. The most significant environmental factors causing the genetic variance in the analyzed sheep breeds appeared to be the geographical latitude and the annual mean temperature. The genetic variance of the coarse-wool sheep breeds was generally higher at low geographical latitudes, which corresponds to the data obtained for the other vertebral species. Therefore, the protection of sheep populations inhabiting the areas at the low geographical latitudes can better maintain the intraspecific diversity. This fact should be especially considered when planning the programs to conserve the biodiversity of farm animals. The breeds of sheep reared near the centers of domestication are distributed in the low latitude ranges. They have a higher genetic variance. Therefore, they can serve as the source of genes contributing to adaptation under the conditions of global climate change.

A comparison of transcriptomic patterns measured in the skin of Chinese fine and coarse wool sheep breeds

We characterised wool traits, and skin gene expression profiles of fine wool Super Merino (SM) and coarse wool Small Tail Han (STH) sheep. SM sheep had a significantly higher total density of wool follicles, heavier fleeces, finer fibre diameter, and increased crimp frequency, staple length and wool grease (lanolin) production. We found 435 genes were expressed at significantly different levels in the skin of the two breeds (127 genes more highly in SM and 308 genes more highly in STH sheep). Classification of the genes more highly expressed in SM sheep revealed numerous lipid metabolic genes as well as genes encoding keratins, keratin-associated proteins, and wool follicle stem cell markers. In contrast, mammalian epidermal development complex genes and other genes associated with skin cornification and muscle function were more highly expressed in STH sheep. Genes identified in this study may be further evaluated for inclusion in breeding programs, or as targets for therapeutic or genetic interventions, aimed at altering wool quality or yield. Expression of the lipid metabolic genes in the skin of sheep may be used as a novel trait with the potential to alter the content or properties of lanolin or the fleece.

Biological Features Depending on Pigmentation and Ekzogormons Application For Increase of Reproduction and Meat Efficiency of Kazakh Fat-tailed Coarse Wool Sheep

Biological Features Depending on Pigmentation and Ekzogormons Application For Increase of Reproduction and Meat Efficiency of Kazakh Fat-tailed Coarse Wool Sheep

Comparative in Vivo Confocal Microscopical Study of the Cornea Anatomy of Different Laboratory Animals

Purpose: The aim of the present study was to analyze and compare in vivo morphology of healthy cornea of six different laboratory animals.Matherials and Methods: One Pomeranian Coarsewool sheep, 5 Beagle dogs, 1 Norwegian and 2 Domestic Short-haired cats, 20 New Zealand White rabbits, 6 Wistar rats, and 10 Balb/c mice were included. The examination was performed bilaterally, using Heidelberg Retina Tomograph equipped with Rostock Cornea Module. The morphology of living corneal layers was visualized and compared between species. The central corneal thickness, density of keratocytes, and endothelial cells were quantified.Results: The epithelial multilayer showed a similarity in morphology between animal types, displaying three clearly distinguishable layers: superficial, intermediate, and basal. Subbasal nerve fibers were displayed as hyperreflective structures underneath basal cells. The subbasal fibers were confirmed in all species, however, the density varied between species. A pronounced Bowman’s membrane was visualized in sheep. In all other species, however, a thin acellular layer with overlying nerve fibers could be seen between basal epithelial cells and anterior stroma. The keratocytes nuclei could be demonstrated in all species except for mice, where no nuclei but only reflective structures resembling keratocytes cell bodies were detected. Overall, the density of keratocytes nuclei was significantly higher in the anterior than in the posterior stroma. Besides endothelial cells density, the endothelial cells morphology was very similar among all species, except for sheep. The endothelial cells were displayed as polygonal structures with bright cytoplasm and dark borders. In sheep, the appearance of the endothelium was very poor because of a thick hyperreflective Descemet’s membrane.Conclusions: The present study will help researchers consider appropriate models for animal experiments, depending on focus of investigation. In vivo CLSM can be used for the characterization of the living cornea over time, thus, reducing the number of animal experiments.

Assessing genetic diversity and differentiation in Portuguese coarse-wool sheep breeds with microsatellite markers

Population structure and genetic diversity in the Portuguese native breeds of sheep Algarvia (AL), Badana (BA), Galega Bragançana (GB), Galega Mirandesa (GM), Mondegueira (MO) and Churra da Terra Quente (TQ), as well as the exotic Assaf (AS), were analyzed by typing 25 microsatellite markers in 210 individuals. The markers used exhibited high levels of polymorphism, with means for total and effective number of alleles per locus of 13.0 and 4.2, respectively, and an expected heterozygosity of 0.72 across loci. The mean number of alleles per locus and expected heterozygosity were highest in GM and GB, and lowest in AS. Exclusive alleles were found in 10 of the 25 markers analysed, mostly in the AS breed. The proportion of loci which were not in Hardy–Weinberg equilibrium in each breed ranged between 0.12 (GB) and 0.40 (AL and GM), mostly due to a lower than expected number of heterozygotes in those loci. All breeds showed a significant deficit in heterozygosity, which was more pronounced in GM ( F IS = 0.113) and BA ( F IS = 0.103), suggesting that inbreeding might be a major concern in these breeds. The analysis of relationships among breeds, assessed by different methods, indicates that AS and AL are the more distanced breeds relative to the others, while the closest relationships were observed between TQ with MO and GM with GB. The estimated F ST indicates that only 0.049 of the total genetic variability can be attributed to differences among breeds, and this ratio dropped to 0.029 when only the native breeds were considered. The analysis of individual distances based on allele-sharing indicates that only AS and AL had a tendency for animals of the same breed to cluster together, while for the other breeds there was overlapping among breeds. The results of this study confirm that native breeds of sheep represent an important reservoir of genetic diversity, even though the level of differentiation among closely located breeds tends to be rather small. For several of the breeds analyzed, the levels of inbreeding currently observed cause some apprehension, and recommend the establishment of appropriate conservation strategies, aimed at minimizing inbreeding to avoid further losses of genetic diversity.

Environment and genetic factors affecting wool production from sub-tropical coarse wool sheep

SUMMARYWool production from different flocks of Ossimi, Rahmani and Barki Egyptian local sheep, raised at six different locations in the country was studied. Different genetic parameters for greasy fleece weight of the three breeds were estimated.Location was of significant effect on annual greasy fleece weight of Rahmani sheep only. With the adjustment for differences in yield percentages, differences in clean wool production from one location to another were slight for the three breeds. Age of ewe was of highly significant effect on annual greasy fleece weight.Heritability estimates of annual greasy fleece weight of the ewes were found to be generally low in the three breeds (range 0·00–0·34). The estimates differed markedly with age; those of the yearling fleece weight of Rahmani and Barki ewes were the highest, being 0–19 and 0–34, respectively.Repeatability estimates of annual greasy fleece weight were also low, being 0·11–0·04 and 0·29 for Ossimi, Rahmani and Barki ewes, respectively.Estimates of genetic correlation between yearling greasy fleece weight of the Ossimi and Rahmani ewes and their weaning and yearling body weights were high and positive. Those between annual greasy fleece weight of the ewes and their reproductive performance traits differed greatly in the two breeds.

Some wool follicle characteristics in crossbreds between Egyptian coarse wool sheep and long and fine-wool breeds

SUMMARYInternal and external follicle diameters of both primary and secondary follicles of Texel x Ossimi and Merino x Barki ewes were greater, at birth, than those in either respective parent breed; the density of primary follicles at birth was less in the cross-breds than in the parental breeds, for both crosses. There was a greater increase of follicle diameter with age in the Egyptian breeds, and mean follicle diameters of the crossbreds were intermediate between those of parent breeds at ages of 3–6 months and above.Grading up Ossimi sheep with the Caucasian Merino resulted in progressive decrease of mean internal follicle diameter. The F2, with more merino blood, had a greater frequency of the smallest diameter follicles than had the F1.