Whole-Genome Selective Scans Detect Genes Associated With Important Phenotypic Traits in Sheep (Ovis aries)

Sheep (Ovis aries) is one of the important livestock with diverse phenotypic traits. However, little is known about the molecular mechanism of diverse phenotypic traits in domestic sheep. Using the genome-wide high-density SNP data (600K) in 253 samples from 13 populations, we conducted the tests of selective sweeps (i.e., pairwise FST and XP-CLR) associated with several important phenotypic traits (e.g., tail types, horn morphology, prolificacy, coat pigmentation, ear size, milk production, meat production, body size and wool fineness). We identified strong selective signatures in previously reported (e.g., T, RXFP2, BMPR1B, TYRP1, MSRB3, TF, CEBPA, GPR21 and HOXC8) and novel genes associated with the traits, such as CERS6, BTG1, RYR3, SLC6A4, NNAT and OGT for fat deposition in the tails, FOXO4 for fertility, PTCH1 and EMX2 for ear size, and RMI1 and SCD5 for body size. Further gene annotation analysis showed that these genes were identified to be the most probable genes accounting for the diverse phenotypic traits. Our results provide novel insights into the genetic mechanisms underlying the traits and also new genetic markers for genetic improvement in sheep and other livestock.

Genome analyses revealed genetic admixture and selection signatures in Bos indicus

The genomic diversity and relationship among seven diverse cattle breeds viz. Sahiwal, Tharparkar, Gir, Vechur, Ongole, Kangayam and Hariana were investigated in 132 random samples based on high density SNP array comprising > 777 K SNPs. A total of 1993 SNPs (0.25% of the total) having greater power (FST ≥ 0.20) to differentiate these cattle populations were identified, and utilized to partition genome of each animal into a predefined number of clusters. The structure of these cattle indicated shared ancestry of dairy breeds viz. Gir, Tharparkar and Sahiwal. Most of the animals (> 76%) of different populations under study except Vechur clustered into their own group of animals called breed. Vechur population retained highest rate of admixture, consistent with its crossing with other breeds. Ongole, Kangayam and Hariana shared comparatively less of their genome (≤ 15%) with other breeds. The study indicated that all seven breeds evolved from their independent ancestry but there was intermixing of these breeds in the recent past. The selection signatures identified between draft (Kangayam) and dairy breeds included several genes like FAM19A2, RAB31P, BEST3, DGKA, AHCY, PIGU and PFKP which are involved in immune response, metabolic pathway, transportation of glucose and sugars, signaling pathways, cellular processes, cell division and glycolysis regulation, respectively. Moreover, these genomic regions also harbour QTLs affecting milk performance traits. The signatures were also identified even between the dairy breeds. In comparison to large-sized cattle, there were significant differences in the number of QTLs affecting production (body weight, growth rate etc.) and morphological traits (height) in short-statured Vechur breed. The presence of HMGA2 gene in the selection signature on chromosome 5 may explain the variations in stature between these cattle.

Costs and Benefits of Wax Production in the Larvae of the Ladybeetle Scymnus nubilus

BACKGROUND: Larvae of the minute aphidophagous Scymnus nubilus Mulsant (Coleoptera: Coccinellidae) are common predators in apple orchards, covered by a wax layer that might act as a defense mechanism against natural enemies. However, the costs and benefits of protection conferred by wax remain to be assessed. We tested the following hypothesis: there is a trade-off in wax producing ladybeetles between the protection conferred by wax cover and the physiological or behavioral costs associated with its production. We predict that: (1) wax production is an efficient defensive mechanism (against intraguild predation), (2) wax production is associated with detrimental physiological (growth, reproduction) or behavioral effects (behavioral compensation: increased biomass consumption). RESULTS: Tests were carried out in the laboratory with wax and waxless larvae of S. nubilus, with and without lacewing larvae of Chrysoperla agilis (Neuroptera: Chrysopidae) being used as a potential intraguild predator of the coccinellid. Waxless individuals were more susceptible to intraguild predation by lacewing larvae. Adults originating from waxless larvae were lighter than the ones originating from wax larvae, suggesting a metabolic cost resulting from a constant need of wax production. Body-weight gain and conversion efficiency were lower in waxless larvae. Biomass consumption was similar, showing that waxless larvae did not compensate for the physiological cost by eating more aphid biomass. CONCLUSION: The results indicate the potential existence of a trade-off between growth and protection associated with wax production.

Evaluation of the glutathione concentration in whole blood of dairy Holstein cows

The objective of this study was to evaluate the concentrations of the total (T-GSH), oxidised (GSSG) and reduced (GSH) glutathione in the blood of dairy cows, assess the relationships of the phase and number of lactation, milk production, body condition score (BCS) and selected biochemical parameters on its concentrations. We analysed 79 samples of whole blood from dairy Holstein cows. The concentration of glutathione was assessed by the spectrophotometric enzymatic method. The whole dataset shows the mean concentration of T-GSH, GSSG and GSH of 803 ± 22 µmol/l, 23 ± 2.5 µmol/l and 757 ± 27 µmol/l, respectively. The GSH/GSSG ratio was 95 ± 17. The phase of the lactation had a significant impact on the levels of T-GSH and GSH, but the number of lactation and BCS had no effect. Dry cows had higher levels of T-GSH (938 ± 44 µmol/l) than the fresh (713 ± 46 µmol/l) and peak lactation (785 ± 45 µmol/l) cows. The fresh cows had significantly lower concentrations of GSH (618 ± 44 µmol/l) than the peak lactation (719 ± 46 µmol/l) and dry cows (827 ± 43 µmol/l). On the basis of a regression analysis, blood glutathione was affected mainly by the liver function and energy metabolism. Glutathione as the marker of oxidation stress seems to be a promising tool in monitoring the health and welfare of the herd, yet intensive research in this field remains necessary.

Influence of the cost of technological equipment of body production on indicators of efficiency of working processes

The possibilities for the development of bodywork in the context of the growing level of competition are analyzed in the article. The technological processes of bodywork are considered and the problem of choosing technological equipment is indicated. The statistical data about the efficiency indicators of company body divisions, operating in the body repair market in Krasnoyarsk, are presented. A composite quality index for the equipment of the bodywork department (using the example of body stocks) is proposed and calculated, and on its basis, some recommendations are given for companies which plan to enter the market of body repair services. Keywords: body production, body repair, body equipment, body production efficiency, selection of technological equipment

INDICATORS OF EARLY MATURITY OF SHEEP AND FACTORS, THEIR DETERMINING THEM

As indicators associated with the precocity of sheep, the following are considered: pedigree, the direction of productivity, the level of growth, early fat deposition in the body, feed costs for production, body types of animals, protein-quality indicator (PQI).

Prepartum lameness on subsequent lactation in Holstein dairy cows

ABSTRACT: The aim of this study was to confirm the possible consequences of prepartum lameness on subsequent lactation among Holstein cows. In this research, 27 multiparous cows, were monitored from the 30th to 63rd day, relative to calving. Thirty days prior to parturition, the animals were segregated into two groups based on the locomotion score (LS), where LS 1 is attributed to animals without claudication, LS 2 to those with suspected lameness and LS 3, 4 and 5 to those with mild, moderate and severe lameness, respectively; in the lame cows group (LC) (n=15), the animals displayed LS ≥ 3, whereas in the non-lame cows group (NLC) (n=12) they showed LS 1. Milk production, body condition score (BCS) and blood concentration levels of β-hydroxybutyrate (BHB), urea, phosphorus, calcium aspartate aminotransferase (AST), gamma glutamyl transferase (GGT) and total plasma proteins (PPT) were evaluated. Milk production (17.675 ± 0.31 L of milk/day) and blood calcium concentration (7.42 ± 0.12 mg/dL) were lower in the lame cows in comparison to those without lameness (22.27 ± 0.42 L of milk/day and 9.63 ± 0.13 mg/dL). Besides, the lame cows showed higher BCS loss during the early postpartum period. The metabolites AST, GGT, PPT, urea, BHB and phosphorus revealed no difference between the groups during the period evaluated. The lameness evident in cows during prepartum exerted major negative effects on the milk production and calcemia, making the LS evaluation during these period an important tool in the early diagnosis of losses for future lactation.