Assaf Breed Research Articles

Evaluation of performance and estimation of genetic parameters for milk yield and reproductive traits in Awassi and Asaf sheep breeds and crosses in the Palestinian territory.

This study aimed to estimate genetic parameters, including heritability and repeatability, for milk yield and prolificacy in sheep. It included 3682 records from 1837 ewes across various breeds: Awassi, Assaf, and Awassi x Assaf crosses, two Awassi lines: Improved Awassi, AFEC Awassi. The study measured total milk yield (TMY), yield up to 120 days (TMY120), and yield up to 150 days (TMY150), alongside reproductive traits: litter size (LS), number of lambs born alive (NLBA), and lambing interval (LI). The analysis utilized a mixed model and the REML procedure to estimate genetic parameters. Results indicated that litter size (LS) had no significant impact on milk traits, whereas breed, location, ewe parity, and lambing season showed significant effects. Lactation length also significantly influenced TMY. For reproductive traits, treatment was significant for NLBA, with location associated with breed, parity, and season affecting all traits. Heritability estimates for TMY ranged from 0.00 in Awassi x Assaf crosses to 0.11 in Awassi, and for TMY120 and TMY150, from 0.00 in Awassi x Assaf crosses to 0.16 in Awassi. Estimates for LS and NLBA varied similarly. The heritability for LI was 0.03 in Awassi and zero in other breeds and crosses. The findings suggest that in the northern West Bank regions of Nablus and Jenin, Assaf or Awassi x Assaf breeds are preferable. The study underscores the importance of comprehensive performance and pedigree recording for effective sheep farm management.

Secretory IgA as Biomarker for Gastrointestinal Nematodes Natural Infection in Different Breed Sheep.

Specific IgA antibody has been shown to play an important role in resistance to gastrointestinal nematode (GIN) infections in sheep, particularly in Teladorsagia circumcincta parasitosis. In some breeds, negative associations have been shown between IgA levels and worm burden in experimentally infected sheep. In the present study, we have studied the relationship between IgA levels in naturally infected sheep (582 ewes in total; 193 younger than one year old and 389 older than one year old) and fecal egg count (FEC) in the Assaf, Castellana, and Churra breeds. ELISA assays were performed to measure IgA levels against the somatic antigen of T. circumcincta third larval stage (L3) and a 203-amino-acid fragment of the protein disulfide isomerase from the same GIN species. A multilevel random intercept model was developed to predict the infection risk according to age or breed. Spearman's correlation rank was used for statistical analysis. The prediction model showed that breed was not an influential factor in this study, although the Assaf breed could be considered slightly more susceptible than the others. In addition, age affected the infection risk, with the young ewes more susceptible to infection than the adult groups, except for the Castellana breed, whose risk of infection was similar at all ages. The most significant positive association was found between FEC and IgA measured in the nasal secretions of young ewes using both antigens (Rho = 0.5; p = 0.00); the correlation of FEC with IgA in serum was moderately significant (Rho = 0.306; p = 0.00). Comparing both antigens, the protein disulfide isomerase antigen was less reactive than the somatic antigen from L3. In conclusion, under natural conditions, specific IgA against GIN was positively associated with FEC in sheep, with nasal secretions from young animals being the sample where this association is stronger, which, therefore, could be used as a marker of infection in further studies.

GHG Emissions from Dairy Small Ruminants in Castilla-La Mancha (Spain), Using the ManleCO2 Simulation Model.

Simple SummaryGreenhouse gas emissions from ruminants contribute to global warming. “ManleCO2” is an empirical model that simulates different management aspects in dairy sheep and goat farming, linking milk production to farming and environmental health. The carbon footprint of 1 L of fat- and protein-corrected milk varied from 2.01 to 5.62 kg CO2e. Simulation scenarios showed a higher reduction in GHG emissions associated with animal feeding strategies and a lower reduction associated with farming management strategies. ManleCO2 may provide useful information for planning and developing different strategies that might support the reduction of GHG emissions at the dairy sheep and goat farm level.The first goal of this work was the description of a model addressed to quantify the carbon footprint in Spanish autochthonous dairy sheep farms (Manchega group), foreign dairy sheep farms (foreigners group: Lacaune and Assaf breeds), and Spanish autochthonous dairy goat farms (Florida group). The second objective was to analyze the GHG emission mitigation potential of 17 different livestock farming practices that were implemented by 36 different livestock farms, in terms of CO2e per hectare (ha), CO2e per livestock unit (LU), and CO2e per liter of fat- and protein-corrected milk (FPCM). The study showed the following results: 1.655 kg CO2e per ha, 6.397 kg CO2e per LU, and 3.78 kg CO2e per liter of FPCM in the Manchega group; 12.634 kg CO2e per ha, 7.810 CO2e kg per LU, and 2.77 kg CO2e per liter of FPCM in the Foreigners group and 1.198 kg CO2e per ha, 6.507 kg CO2e per LU, and 3.06 kg CO2e per liter of FPCM in Florida group. In summary, purchasing off-farm animal feed would increase emissions by up to 3.86%. Conversely, forage management, livestock inventory, electrical supply, and animal genetic improvement would reduce emissions by up to 6.29%, 4.3%, 3.52%, and 0.8%, respectively; finally, an average rise of 2 °C in room temperature would increase emissions by up to 0.62%.

INFLUENCE OF MORPHOLOGICAL INDICATORS OF SEEDS OF RAMS OF DIFFERENT BREEDS ON THE QUANTITY AND QUALITY OF SPERM PRODUCTS

Assessment of sperm quality is an important part of the technological process. Fertility of uteruses and bright depends to a large extent on quality of sperm. Before fertilization, you can get an idea of ​​the quality of sperm, to determine some indicators (volume, activity, density) that characterize certain properties.
 The main method of research in the production environment is the visual assessment of sperm by density and motility, concentration and resistance, and the percentage of live sperm.
 The testes are a pair of ovoid tubular glands that are located in the testis sac, the outer layer of which is called the scrotum. Each testicle is covered with three shells: protein (covers the surface of the testicle), a special vagina and a common vagina. At the head of the testis, where the head of the appendix departs, the protein shell grows deep into the testis, forming the mediastinum of the testis, and divides the parenchyma into many lobes or chambers. Inside the chambers are thin tubes (0.1-0.2 mm) - twisted tubules of the testis, covered with delicate connective tissue and interstitial cells. The quality and quantity of sperm production of rams of different breeds (assaf, dorper, merinoladshaf) were studied. It was found that sheep of the dorper breed of meat productivity in terms of ejaculate volume exceed the indicators of sheep of the breed assaf dairy-meat direction by 0.11 ml or 20%, and compared with sheep of meat-wool direction of productivity of the breed merinolandshaf respectively by 0.1 ml or 17.8%. According to the semen density of sheep of the assaf breed, the indicators of dorper and merinoladshaf were compared. The average density of semen of sheep of the assaf breed is exceeded in comparison with the dorper breed by 2 times and that of the merinoladshaf by 4 times. Dorper and merinoladshaf had liquid semen, which was estimated at 2 points. The sperm of all breeding rams had a rectilinear oscillating motion. High-quality semen was found in rams of all breeds and was evaluated at 9 points in rams of the assaf breed, and in rams of the dorper and merinoladshaf breeds - at 8 points.

Comparison of microbiota and volatile organic compounds in milk from different sheep breeds

In this study, we compared the microbiota and volatile organic compounds (VOC) present in the milk obtained from 3 different sheep breeds, namely Merino, Lacaune, and Assaf. Udder milk was collected from 21 animals, 7 from each breed. Bacterial microflora was determined metagenomically by extracting the DNA from the milk and analyzing the V3-V4 region of the 16S rRNA gene. Headspace solid-phase microextraction gas chromatography-mass spectrometry method was used to analyze VOC. The metagenomic analysis revealed (for Merino, Lacaune, and Assaf milk, respectively) Firmicutes (66.32, 69.36, and 57.08%), Actinobacteria (19.09, 7.67, and 19.40%), Proteobacteria (13.76, 21.06, and 22.19%), and Bacteroidetes (0.84, 1.91, and 1.33%) phyla in the milk samples. Lactobacillus was highly abundant in the milk of 3 breeds (29.64, 43.50, and 18.70%). The genera constituting more than 2% of all bacteria in all groups were Jeotgalicoccus (7.19, 5.34, and 10.77%), Enterococcus (5.18, 9.78, and 3.64%), and Corynebacterium (4.08, 3.00, and 13.44%). A total of 32 different VOC were identified by headspace solid-phase microextration analysis with 9, 30, and 24 different compounds from Merino, Lacaune, and Assaf breeds, respectively. Although ketone was the most abundant compound in Merino milk (71.84%), hydrocarbons were the most detected in Lacaune and Assaf milk (37.18% and 55.42%, respectively). A positive correlation was found between acetone, which was detected at the highest level in all groups, with Salinicoccus, Alloiococcus, Psychrobacter, and Dietzia. In addition, a negative correlation was found between the Lactobacillus genus, detected at the highest level in all groups, with methyl cyclopentane, 3-methylheptane, octane, decane, 3,3-dimethyloctane, and dodecane. Thus, differences were observed in the bacterial microflora and VOC in the sheep milk from different breeds under different feeding and breeding conditions.

Genome-wide association studies (GWAS) and post-GWAS analyses for technological traits in Assaf and Churra dairy breeds

This study aimed to perform a GWAS to identify genomic regions associated with milk and cheese-making traits in Assaf and Churra dairy sheep breeds; second, it aimed to identify possible positional and functional candidate genes and their interactions through post-GWAS studies. For 2,020 dairy ewes from 2 breeds (1,039 Spanish Assaf and 981 Churra), milk samples were collected and analyzed to determine 6 milk production and composition traits and 6 traits related to milk coagulation properties and cheese yield. The genetic profiles of the ewes were obtained using a genotyping chip array that included 50,934 SNP markers. For both milk and cheese-making traits, separate single-breed GWAS were performed using GCTA software. The set of positional candidate genes identified via GWAS was subjected to guilt-by-association-based prioritization analysis with ToppGene software. Totals of 84 and 139 chromosome-wise significant associations for the 6 milk traits and the 6 cheese-making traits were identified in this study. No significant SNPs were found in common between the 2 studied breeds, possibly due to their genetic heterogeneity of the phenotypes under study. Additionally, 63 and 176 positional candidate genes were located in the genomic intervals defined as confidence regions in relation to the significant SNPs identified for the analyzed traits for Assaf and Churra breeds. After the functional prioritization analysis, 71 genes were identified as promising positional and functional candidate genes and proposed as targets of future research to identify putative causative variants in relation to the traits under examination. In addition, this multitrait study allowed us to identify variants that have a pleiotropic effect on both milk production and cheese-related traits. The incorporation of variants among the proposed functional and positional candidate genes into genomic selection strategies represent an interesting approach for achieving rapid genetic gains, specifically for those traits difficult to measure, such as cheese-making traits.

THE EFFECTIVENESS OF THREE-BREED CROSSINGS FOR INCREASING MEAT PRODUCTIVITY IN YOUNG SHEEP

This publication presents the results on the growth, development, live weight, body indices in ram lambs and ewe lambs of three-breed crossbreeds ♀ (♀Karakul 18.7% x ♂Avassi 31.3%) x ♂Assaf 50.0% and purebred Assaf, as well as the dynamics of the live weight gain of lambs from birth to 4–4.5 months of age. Crossbreed lambs are developed better than purebred lambs. The absolute weight gain in the ram lambs ♀ (♀Karakul 18.7% x ♂ Avassi 31.3%) x ♂Assaf50.0% was 4.8 kg, which is by 0.32 kg (7.1%) higher in relation to the ram lambs of the Assaf breed, the average daily weight is also higher by 5.4 g. According to the same trend, crossbred ewe lambs had a gross weight gain of 3.72 kg or by 0.22 kg (6.3%) more than in purebred ones and the average daily weight are also higher by 3.2 g.
 Of the eight body indices, crossbred ram lambs and ewe lambs have five indices that exceed the obtained indicators in purebred animals, and in purebred lambs only three body indices are superior. In ram lambs of the Assaf breed, the indicators for three indices are higher in comparison to crossbreeds: transverse by 0.78%, chest by 0.5% and robustness by 4.65%, and for three-breed crossbreeds they are higher in relation to purebred ones according to the following 5 indices: body format by 4.33%, massiveness by 1.28%, bones by 0.58%, forehead width by 3.74% and head length by 1.42%. The indices of body format, bones and head length are also higher in the purebred ewe lambs by 0.12%, 0.46% and 1.36%, and in the crossbreeds the indices of transverse, massiveness, chest, and head width are higher by 1.21%, 1.35%, 2.02%, 0.29% and 2.97%.
 The slaughter qualities of crossbreeds are higher for the most indicators taken into account, with the exception of the area of sheepskins. The slaughter weight of crossbred ram lambs is higher by 1.62 kg (13.2%) compared to purebred ram lambs, and the slaughter yield of carcasses is also higher by 2.88%. After deboning chilled half-carcasses, the mass of meat was higher in crossbred animals in comparison to purebred animals by 0.59 kg or 14.8%. All this denoted an higher meat ratio characterizing the relative development of bones and muscle tissues in crossbred animals with made up 2.51 vis-a-vis 2.34 in purebred ones. The highest weight of sheepskins was in crossbred ram lambs and amounted to 3.76 kg, which is by 0.65 kg or by 20.9% more than in peers. At the same time, purebred ram lambs had the largest sheepskins area of 80.3 dm2, which are by 5.52 dm2 (8.51%) more than in crossbreeds.
 The interior parameters of the internal organs, the development of the digestive organs are closely related to the constitutionally productive characteristics of sheep. The internal organs of crossbred ram lambs, which also have the greatest pre-slaughter live weight, are somewhat better developed. At the same time, they surpassed their purebred peers in the mass of the lungs, spleen and kidneys. The weight of the lungs indicates the volume of respiration and the redox processes occurring in it, on which depend the health and endurance of animals. There were no significant differences in the absolute weight of the lungs in both groups of animals and they were almost the same and ranged from 0.550 g to 0.555 g. Thus, our results indicate that there is a positive relationship between the productivity of ram lambs and the development of their internal organs.
 The digestive organs and their development ensure the future productivity of the animal. Crossbreed lambs by weight of the stomach without the contents of 973.2 g exceed they peers by 1.4%. The total length of the intestine also for this group of ram lambs is 36.38 meters or more than by 2.36%. In total, all this can lead to better use of the feed, increasing its digestibility.
 At the ends of the slaughter were taken from each carcass their measurements and the indices were calculated. In crossbred three-breed ram lambs, all carcass evaluation indices are higher in comparison with purebred ones, with the exception of the chest depth index. The lamb leg development index in crossbreeds is significantly higher by 22.52% (P < 0.01), and in Assaf ram lambs is significantly higher the breast depth index if compared to crossbreeds by 14.61% (P < 0.001).
 According to the chemical composition of meat in the group of purebred ram lambs and in the group of crossbreeds, the content of water in meat, protein and collagen is within the normal range and almost the same.
 The high fat values in three-breed crossbreeds are 6.88%, which is by 2.15% more than in purebreds.

Genome-Wide Association Studies of Somatic Cell Count in the Assaf Breed.

Simple SummaryMastitis causes economic loss due to discarded milk and reduced milk production and quality, increased medical care costs and somatic cell count (SCC) penalties. The use of genetic markers associated with the variability of this trait through marker-assisted selection (MAS) could help traditional methods. Our objectives were to identify new single nucleotide polymorphisms (SNPs) and genes associated with mastitis resistance in Assaf sheep by using the Illumina Ovine Infinium® HD SNP BeadChip (680K). Firstly, corrected phenotype estimates for somatic cell score (SCS) were calculated using 6173 records from 1894 multiparous Assaf ewes, and were used to select 192 extreme animals (low SCS group: n = 96; and high SCS group: n = 96) for the genome-wide association study (GWAS). Four SNPs (rs419096188, rs415580501, rs410336647, and rs424642424), three of them totally linked, were found to be significant at the chromosome level (FDR 10%) in two different regions of OAR19 close to genes related to the immune system response. Validation studies of two SNPs (rs419096188 and rs424642424) by Kompetitive Allele-Specific PCR (KASP) genotyping in the total population (n = 1894) confirmed previous GWAS association results for the SCS trait. Finally, the SNP rs419096188 was also associated with lactose content trait.A genome-wide association study (GWAS) was performed to identify new single nucleotide polymorphisms (SNPs) and genes associated with mastitis resistance in Assaf sheep by using the Illumina Ovine Infinium® HD SNP BeadChip (680K). In total, 6173 records from 1894 multiparous Assaf ewes with at least three test day records and aged between 2 and 7 years old were used to estimate a corrected phenotype for somatic cell score (SCS). Then, 192 ewes were selected from the top (n = 96) and bottom (n = 96) tails of the corrected SCS phenotype distribution to be used in a GWAS. Although no significant SNPs were found at the genome level, four SNPs (rs419096188, rs415580501, rs410336647, and rs424642424) were significant at the chromosome level (FDR 10%) in two different regions of OAR19. The SNP rs419096188 was located in intron 1 of the NUP210 and close to the HDAC11 genes (61 kb apart), while the other three SNPs were totally linked and located 171 kb apart from the ARPP21 gene. These three genes were related to the immune system response. These results were validated in two SNPs (rs419096188 and rs424642424) in the total population (n = 1894) by Kompetitive Allele-Specific PCR (KASP) genotyping. Furthermore, rs419096188 was also associated with lactose content.

Influence of the Breed of Sheep on the Characteristics of Zamorano Cheese

This work aimed to study the effects of using ewe’s milk from Churra, Assaf, or both breeds on the physicochemical and sensory characteristics of Zamorano cheese at the end of ripening. Zamorano cheese is a hard variety with protected designation of origin (PDO) produced in the province of Zamora (Spain) with raw or pasteurized ewe’s milk. Five batches of Zamorano cheese were produced with pasteurized ewe’s milk. One batch was elaborated using milk from the Churra breed, the other using milk from the Assaf breed, and the remaining three employed milk mixtures of Churra and Assaf breeds in the proportions 75:25, 50:50 and, 25:75, respectively. Cheeses made with a higher proportion of Churra milk showed a predominance of hydrophilic peptides, while hydrophobic peptides predominated in cheeses with a greater percentage of milk from the Assaf breed. The largest content of most free amino acids was found in cheeses produced with the highest percentage of Churra milk. These cheeses presented the highest values for fat acidity index and free fatty acids content and showed greater elasticity and adhesiveness, as well as lower granularity and hardness. In the sensory evaluation, aftertaste and persistence were higher in these cheeses, being scored with the best overall values.

Economic efficiency of Bulgarian dairy synthetic population and Assaf sheep breeds

Abstract. The economic efficiency of ewes from the Bulgarian dairy synthetic population (BDSP) and Assaf sheep breeds, reared in three production systems, e.g. grazing on pasture, stall-pasture rearing and stall rearing was studied. The results from the study showed that BDSP ewes in the stall-pasture rearing system had a relatively low milk yield for a specialised dairy sheep breed – 80L for the lactation period. In this system, without the subsidy, the profit and cost efficiency were negative, while with subsidy, minimum positive results were achieved. For BDSP ewes reared in a stall-pasture rearing system with stall feeding during the grazing period and grazing on improved pastures, the obtained milk yield was by 33% higher. The subsidy resulted in satisfactory profit and cost efficiency, while without the subsidy, the farm ended in loss. BDSP and Assaf ewes reared in stalls, demonstrated substantially higher milk yield and productivity. They realised a profit and good cost efficiency. The milk yield of BSDP sheep reared in stalls was 200L per lactation, and fertility – 140%. The Assaf breed in which a high level of selection and regulated reproduction cycle was achieved, had 250L milk per lactation and 140% fertility. The profit with subsidy was 128.85 BGN (1Lev=0.975€) and without the subsidy: 48.85 BGN, with relatively high cost efficiency. An introduction of traits for higher milk yield, polyestrus and fertility from Assaf into BSDP sheep is necessary.

Analysis of Prion Protein Coding Gene Polymorphisms in Palestinian Native Sheep Breeds

Prion protein coding gene (PRNP) is the genetic locus correlated with the greatest impact on classical scrapie susceptibility in sheep. At codons 136, 154, and 171 of PRNP alanine/arginine/glutamine (ARQ) and valine/arginine/glutamine (VRQ) haplotypes, in turn, are related to susceptibility to classical scrapie while alanine/arginine/arginine ARR haplotype is correlated with resistance. The aim of the present study was to genotype the Palestinian native sheep breeds for detection of genetic resistance. A total of 38 healthy sheep from Awassi and Assaf breeds were randomly sampled. Genomic DNA was isolated from blood samples. After PCR amplification and DNA sequencing, ARQ, ARR, ARH, AHQ, ARL and VRQ alleles and ARR/ARQ, ARQ/ARQ, ARQ/ARL, ARH/ARQ, ARH/ARL, AHQ/ARQ and ARQ/VRQ genotypes were detected in PRNP gene. ARQ allele was found as a predominant allele in this study with the frequency of 0.76 for Awassi and Assaf breeds while the uncommon allele ARL was identified at low frequencies in both breeds. In addition, two different polymorphisms were recognized (V12I and L23H) at different codons of PRNP. Results have indicated that most of the genotypes belong to risk group 3. The careful dissemination of ARR/ARR sheep is suggested to increase resistant allele frequencies in Assaf and Awassi breeds.

Characterization and Comparative Analysis of the Milk Transcriptome in Two Dairy Sheep Breeds using RNA Sequencing.

This study presents a dynamic characterization of the sheep milk transcriptome aiming at achieving a better understanding of the sheep lactating mammary gland. Transcriptome sequencing (RNA-seq) was performed on total RNA extracted from milk somatic cells from ewes on days 10, 50, 120 and 150 after lambing. The experiment was performed in Spanish Churra and Assaf breeds, which differ in their milk production traits. Nearly 67% of the annotated genes in the reference genome (Oar_v3.1) were expressed in ovine milk somatic cells. For the two breeds and across the four lactation stages studied, the most highly expressed genes encoded caseins and whey proteins. We detected 573 differentially expressed genes (DEGs) across lactation points, with the largest differences being found, between day 10 and day 150. Upregulated GO terms at late lactation stages were linked mainly to developmental processes linked to extracellular matrix remodeling. A total of 256 annotated DEGs were detected in the Assaf and Churra comparison. Some genes selectively upregulated in the Churra breed grouped under the endopeptidase and channel activity GO terms. These genes could be related to the higher cheese yield of this breed. Overall, this study provides the first integrated overview on sheep milk gene expression.

Structural characterisation of the acyl CoA: diacylglycerol acyltransferase 1 (DGAT1) gene and association studies with milk traits in Assaf sheep breed

Because DGAT1 plays a fundamental role in triacylglycerol synthesis, existing SNPs in DGAT1 gene might provide important information in partially explaining, the variation of milk fat content in dairy sheep. Therefore, the main objective of this study was to sequence the complete ovine acyl CoA:diacylglycerol acyltransferase 1 (DGAT1)gene in order to identify polymorphisms and to look for its possible association with milk traits in Assaf sheep breed. Polymorphisms identification in the DGAT1gene was carried out in 50 individuals belonging to five sheep breeds reared in Spain: Rasa Aragonesa (n=10), Manchega (n=10), Churra Tensina (n=10), Latxa (n=10) and Spanish Assaf (n=10). The association studies between polymorphisms, and milk traits were carried out using animals belonging to three flocks of Assaf breed (n=402). Four SNPs were detected, one in exon 1 (EU178818: g.358C>A), two in exon 17 (g.8522C>T and g.8539C>T), and one in intron 10 (g.7457C>A). The SNP in exon 1, g.358C>A,generates a non-conservative substitution at position p.Asp53Glu (GenBank ABW24130). The first SNP in exon 17 (g.8522C>T)causes an amino acid change at position p.Arg482Cys.The genotype frequencies were studied in a panel of 9 breed reared in Spain: Ansotana (n=50), Latxa (n=36), Romanov (n=33), Rasa aragonesa (n=55), Churra (n=52), Churra tensina (n=57), Churra lebrijana (n=50), Manchega (n=48) and Assaf (n=402). All breeds were in Hardy–Weinberg equilibrium for all SNPs, except for the SNPs g.8522C>T and g.8539C>T SNPs which showed a deficit of heterozygous animals in Ansotana breed. This gene show low variability in a panel of 9 breeds reared in Spain. The only polymorphism not fixed in Assaf breed was the SNP g.8539C>T, and was used to test possible association with milk traits. The allelic frequency of the 8539C allele was 0.96, being 373 animals homozygous for the CC genotype and 29 heterozygous. The association studies showed that lactose, fatty acids C4:0, C16:1 c9, and the ratio n-6:n-3 were affected by the SNP g.8539C>T. Animals carrying the CC genotype had greater lactose, C4:0 and C16:1 c9 contents and lower ratio of n-6:n-3 compare to the CT ones. Probably the SNP g.8539C>T, is not causative of the variation observed in the lactose content but might be in linkage disequilibrium with the causal mutation located in the same or other closer gene.

Cost structure and profitability of Assaf dairy sheep farms in Spain

Twenty dairy sheep farms of Assaf breed, located in the Spanish autonomous community of Castilla y León and included in a group receiving technical support, were used to study their production cost structure and to assess their economic profitability during 2009. On average, farms had 89.2±38.0 ha (own, 38%), 592±63 ewes, yielded 185.9±21.1×103 L/yr (i.e., 316±15 L/ewe), and were attended by 2.3±0.2 annual working units (family, 72%). Total annual income was €194.4±23.0×103/yr (€1.0=$1.3) from milk (78.6%), lamb (13.2%), culled ewes (0.5%), and other sales (0.8%, wool and manure), and completed with the European Union sheep subsidy (6.9%). Total costs were €185.9±19.0×103/yr to attend to feeding (61.6%), labor (18.2%), equipment maintenance and depreciation (7.6%), finances (3.0%), animal health (2.5%), energy, water and milking supplies (2.2%), milk recording (0.5%), and other costs (4.4%; assurances, shearing, association fees, and so on). Mean dairy sheep farm profit was €8.5±5.8×103/yr (€7.4±8.3/ewe) on average, and varied between –€40.6 and €81.1/ewe among farms. Only 60% of farms were able to pay all costs, the rest had negative balances. Nevertheless, net margin was €31.0±6.5×103/yr on average, varying between €0.6 and €108.4×103/yr among farms. In this case, without including the opportunity costs, all farms had positive balances. Total annual cost (TAC; €/ewe) and total annual income (TAI; €/ewe) depended on milk yield (MY; L/ewe) and were TAC=161.6 + 0.502 MY (R2=0.50), and TAI=78.13 + 0.790 MY (R2=0.88), respectively, with the break-even point being 291 L/ewe. Conversely, farm TAC (€/yr) and farm TAI (€/yr) were also predicted as a function of the number of ewes (NOE) per flock, as TAC=18,401 + 282.8 NOE (R2=0.89) and TAI=330.9 NOE (R2=0.98), with the break-even point being 383 ewes/flock. Finally, according to the increasing trend expected for agricultural commodity prices, it was calculated that a 10% increase of concentrate price will require 5.2% milk price increase for constant profit. Similarly, a 10% increase of forage price will require 2.0% milk price increase to maintain profitability. Under these scenarios of increasing the commodity prices of key feedstuffs, a change of flock feeding should be expected to compensate the losses in farm profitability. Most Assaf dairy sheep farms studied were economically profitable, with flock size, milk yield, and feeding costs key for their profitability.

A typological characterization of dairy Assaf breed sheep farms at NW of Spain based on structural factor

The dairy sheep farms at Central-Nord o Spain have adapted well to the new contextual conditions by introducing highly specialized breeds, increasing flock size or incorporating new production techniques and technologies. This paper describes the analysis procedure and the results obtained from structural characteristics (dimensional, organizative and investments on building, machinery and facilities) for a sample of 44 farms in the study area (León). We collected data in visits to farms with a previously made questionnaire. We processed these data, filtered them with preliminary analysis to later analyze their main components, followed by a hierarchical conglomerate analysis and an ANOVA. As a result, we obtained six distinct groups or types of farms that are representative of dairy sheep production in the study area: (i) large traditional farms (n=4); (ii) small traditional farms (n=6); (iii) farms with a complementary agricultural activity (n=7); (iv) emerging small farms (n=8); (v) modernized medium-sized farms (n=12), and (vi) dairy sheep farms without cultivated land (n=6). According to this distribution, 58% of ewes are concentrated in medium-sized farms (400–800 ewes).Farms differ mainly in size, age or level of consolidation, degree of intensification, level of investment and mechanization, feeding and grazing system or expectations for continuity according to the possibility of succession or owner’s age.Globally, 14% of farms do not produce forage, cereal or any kind of crops; 16% produce forage and cereal for on-farm consumption and sell their surplus and other harvested products; and 70% produces forage and cereal only for on-farm consumption.The high farm investment levels, which are a consequence the resizing of many farms are associated to a modernization of the production systems and directly related to high social expectations for family farm continuity.Dairy sheep farm activity is highly dynamic. However, 25% of Assaf breed sheep farms with owners about to retire or without a successor in the family, may disappear. This could be avoided with the adoption of administrative measures that encourage the transfer to a third party.

Design and “in vivo” evaluation of two adapted catheters for intrauterine transcervical insemination in sheep

In order to obtain better fertility, we evaluated two ovine artificial insemination (AI) catheters that were manufactured according to the anatomical structure of the ewe cervix. Morphometric data of the cervix in Churra and Assaf breeds were used to design two types of curved catheters: CAT06 with one curvature and ZIGZAG with five curvatures in a zigzag shape. Two commercial catheters (IMV® and Minitüb®) were used as controls. In experiment 1, cervical penetration and the degree of reflux were measured in a Cervical AI simulated assay both Churra (n=28) and Assaf ewes (n=28). In experiment 2, a fertility study was performed with three catheters (only one commercial control catheter – IMV) in 465 inseminations (Assaf); and a second study analyzed only the top two catheters (IMV and CAT06) in 428 inseminations (210 Assaf and 218 Churra). The ewes were synchronized using intravaginal sponges (40 FGA mg during 14 days) and 500IU of eCG. Deeper penetration of the cervix was obtained with the new catheters compared with the commercial ones (1.5, 1.3, 3.5 and 3.2cm for the IMV, Minitüb, CAT06 and ZIGZAG catheters, respectively). The cervical penetration and the reflux grade of each catheter showed no differences between breeds. In experiment 2, the degree of penetration had no correlation with fertility of different catheters. The best percentage of lambing ewes was obtained with the IMV and CAT06 catheters (39.5 and 48.1%, respectively. vs 27.2% for ZIGZAG catheter, in the Assaf breed). Regarding effect of breed, Assaf (39.3% and 49.5 for IMV and CAT06, respectively) showed better lambing rates than Churra (29.0% and 39.0%, respectively), and the CAT06 catheter showed significantly higher rates for each breed.

EFECTO DE DOS DILUTORES SOBRE LA MOTILIDAD E INTEGRIDAD DE LA MEMBRANA ESPERMÁTICA EN SEMEN CONGELADO DE OVINOS.

The objective of the study was to evaluate the effects of two semen extenders: Tris- Fructose-egg yolk (Tris) and Citrate-Glucose-egg yolk (citrate) on motility and sperm membrane integrity (HOST) in ovine frozen semen in pellets. The study was carried out at the Semen Bank of the Agrarian University La Molina, in Lima, Peru, using 4 rams (2 Assaf and 2 Blackbelly) of 3.5 to 4 years old. A covariance analysis was used to evaluate the effect of the treatment and breed on Individual Progressive Motility (IPM), and randomized block design to evaluate the effect of extenders on sperm membrane integrity. Semen was frozen of dry ice and thawing was done in test tubes at 38 °C. In the Assaf breed, IPM of thawed semen was 63.77 and 61.11% when using Tris and citrate respectively, showing statistical difference (p<0.05). In the Blackbelly breed the IPM was 62.33 and 61.33%, when used Tris and citrate respectively, and without significant difference. In the Assaf the HOST values of thawed semen were 43.56 and 40.38%, while in Blackbelly were 40.19 and 38.16% respectively, both without significant differences. It is concluded that Tris showed better effect on individual motility but both of them had similar effect on sperm membrane integrity.

Effects of somatic cells on the protein profile of hard ovine cheese produced from different breeds

Bulk tank ewe's milks with low (<500,000 ml(-1)), medium (1,000,000-1,500,000 ml(-1)) and high (>2,500,000 ml(-1)) somatic cell counts (SCC) from three breeds were used to manufacture hard ewes'-milk cheese. Physico-chemical analysis and capillary electrophoresis of fresh cheeses and cheeses that had been ripened for 1, 2, 3 and 6 months were carried out. The results showed that high SCC levels in milk affected the moisture content of only freshly made cheeses and the pH, fat content and fat acidity of ripened cheeses. Regarding proteolysis, the levels of all β-CNs in freshly made cheeses were significantly lower as the SCC values increased and the Castellana breed was the most affected by SCC levels because a significant decrease in all α-CNs was also observed as SCC levels rose. Analysis of the casein profile by principal component analysis (PCA) revealed that there were no clear differences according the SCC up to the third month. However in the third and sixth months cheeses with low levels of SC were closely grouped and characterised by the highest levels of intact caseins. Regarding the effect of breed, the results point to a more intense proteolytic activity in the Assaf breed, whose more matured cheeses showed the highest content of casein proteolytic fragments.

Mini review: breeding Awassi and Assaf sheep for diverse management conditions

The Local Awassi, a triple-purpose breed for meat, milk, and carpet-wool production, is a low-prolific, hardy breed that is well adapted to the unfavorable conditions of the Middle East, where it is managed under traditionally extensive to semi-extensive conditions. Breeding work with the Awassi has included within-breed selection, crossbreeding, and gene introgression. Those efforts resulted in a variety of Awassi-derived genotypes that successfully occupy semi-intensive as well as intensive production systems. Thus, within-breed selection resulted in development of the "Improved Awassi"-a dairy-type Awassi strain which, under intensive management, produces over 500l milk/ewe annually; crossbreeding with the East Friesian breed led to the development of the Assaf dairy breed, which exceeds the Improved Awassi in prolificacy and in year-round breeding activity, and introgression of the B allele of the FecB locus into the Awassi and Assaf breeds resulted in the formation of the prolific Afec Awassi and Afec Assaf strains, with prolificacies of 1.9 and 2.5 lambs born per ewe lambing, respectively. Advanced molecular genetics tools have enabled a better understanding of how the Awassi breed was formed during domestication and have uncovered differences in its genetic structure compared to other breeds. Implementing large-scale selection schemes that implement emerging new information on the sheep genome, overcoming threats of inbreeding depression, and further breeding for high uterine capacity are the new breeding goals for the Awassi, Assaf, and their derivatives.

The influence of breed on the organoleptic characteristics of Zamorano sheep’s raw milk cheese and its assessment by instrumental analysis

The aim of this study was to investigate the effects of three different somatic cell count (SCC) values on the sensory characteristics of sheep’s milk cheeses from the Castellana and Churra breeds (allowed for Protected Designation of Origin Zamorano cheese manufacture) and the Assaf breed (foreign), determined by typical consumers and instrumentally. The results show that the sensory characteristics of hardness, intensity of taste, and pungency reflect a significant influence of the SCCs of the original milk whereas breed significantly affects colour intensity and hardness (Warner‐Bratzler maximum shear force; WBSF). The instrumental parameters most closely related to the assessments of the typical consumers were WBSF and the value of a*, for hardness and colour respectively.