Estimating the Effect of the Kappa Casein Genotype on Milk Coagulation Properties in Israeli Holstein Cows.

In Israel, about 26% of produced milk is used to produce hard cheeses and 29% for soft cheeses. Milk with preferred coagulation properties requires a shorter coagulation time and yields a higher curd firmness than milk with inferior coagulation properties. Studies have shown that milk from cows with the B allele of kappa casein (κ-CN) produces more cheese than milk from those with A and E alleles.

Sounds emitted by plants under stress are airborne and informative.

Stressed plants show altered phenotypes, including changes in color, smell, and shape. Yet, airborne sounds emitted by stressed plants have not been investigated before. Here we show that stressed plants emit airborne sounds that can be recorded from a distance and classified.

Carryover effects of feeding bulls with an omega-3-enriched-diet-From spermatozoa to developed embryos.

The impact of omega-3 nutritional manipulation on semen cryosurvival and quality post thawing is controversial. Our aim was to examine how feeding bulls with omega-3 supplementation from different sources affects the spermatozoa quality parameters. Fifteen Israeli Holstein bulls were fed for 13 weeks with a standard ration top-dressed with encapsulated-fat supplementation: fish or flaxseed oil or saturated fatty acids (control).

Association between Fatty Acid Composition, Cryotolerance and Fertility Competence of Progressively Motile Bovine Spermatozoa.

An association between progressive motility (PM) and spermatozoa fertility competence has been suggested. However, the mechanism that underlies PM is not clear enough. We examined physiological characteristics and fatty acid composition of fresh spermatozoa with high and low PM.

A Cytoplasmic Receptor-like Kinase Contributes to Salinity Tolerance.

Receptor-like cytoplasmic kinases (RLCKs) are receptor kinases that lack extracellular ligand-binding domains and have emerged as a major class of signaling proteins that regulate plant cellular activities in response to biotic/abiotic stresses and endogenous extracellular signaling molecules. We have identified a rice RLCK (OsRLCK311) that was significantly higher in transgenic pSARK-IPT rice () that exhibited enhanced growth under saline conditions. Overexpression of OsRLCK311 full-length protein (RLCK311FL) and the C-terminus of OsRLCK311 (ΔN) in Arabidopsis confirmed its role in salinity tolerance, both in seedlings and mature plants.

Use of computer-assisted sperm analysis and flow cytometry to detect seasonal variations of bovine semen quality.

Seasonal fluctuations of climate are considered a major factor affecting spermatogenesis and semen quality in the bovine. Our study aimed to investigate the effect of season on functional parameters of frozen-thawed bovine semen using computer-assisted sperm analysis (CASA) and flow cytometry. For this purpose, 86 ejaculates were collected from five mature Holstein-Friesian bulls kept under subtropical conditions during summer (August to September; n = 43) and winter (December to January; n = 43) months.

Dietary α-linolenic acid from flaxseed oil or eicosapentaenoic and docosahexaenoic acids from fish oil differentially alter fatty acid composition and characteristics of fresh and frozen-thawed bull semen.

Incorporation rates of dietary omega-3 (n-3) fatty acids (FAs) from different sources into bull plasma and sperm and the effects on physiological characteristics of fresh and frozen-thawed semen were determined. Fifteen fertile bulls were assigned to three treatment groups and supplemented for 13 weeks with encapsulated fat: (1) SFA-360 g/d per bull saturated FA; (2) FLX-450 g/d per bull providing 84.2 g/d C18:3n-3 (α-linolenic acid) from flaxseed oil; and (3) FO-450 g/d per bull providing 8.

Progressive motility - a potential predictive parameter for semen fertilization capacity in bovines.

We examined the association between progressive motility of spermatozoa and in vitro fertilization (IVF) competence of bovine ejaculates. Fresh semen was evaluated using a computerized sperm quality analyzer for bulls using progressive motility as the primary parameter. Ejaculates with high progressive motility (HPM; >81%) were compared with those with low progressive motility (LPM; 0.

Predictive ability of selected subsets of single nucleotide polymorphisms (SNPs) in a moderately sized dairy cattle population.

Several studies have shown that computation of genomic estimated breeding values (GEBV) with accuracies significantly greater than parent average (PA) estimated breeding values (EBVs) requires genotyping of at least several thousand progeny-tested bulls. For all published analyses, GEBV computed from the selected samples of markers have lower or equal accuracy than GEBV derived on the basis of all valid single nucleotide polymorphisms (SNPs). In the current study, we report on four new methods for selection of markers.

Variation in lipid profiles within semen compartments--the bovine model of aging.

Semen lipid composition was examined in young and mature bulls. Given the specific roles of various semen compartments (i.e.

Maternity validation using sire-only BovineSNP50 BeadChip data.

Based on pairwise identity-by-state (IBS) distances and whole-genome SNP data, kinship was investigated in the Israeli Holstein population. A total of 789 bulls, including most of the artificial insemination sires in service since 1987, were genotyped by the BovineSNP50 BeadChip. This sample included up to five generations.

Season-induced variation in lipid composition is associated with semen quality in Holstein bulls.

Season-induced variation in fatty acid and cholesterol composition in bovine semen has been associated with semen quality. Given the specific roles of the various semen compartments (seminal fluids, sperm head, and sperm tail) in fertilization, we hypothesized that environmental-stress-induced alterations in the lipid composition of a specific compartment might impair semen quality and sperm function. Semen samples were collected from five mature Holstein-Friesian bulls during the summer (August to September) and winter (December to January).

Signatures of contemporary selection in the Israeli Holstein dairy cattle.

Strong selection in the Israeli Holstein dairy cattle population over the last three decades should have left clear signatures of selection. Two experimental approaches were applied to detect evidence of contemporary selection based on the 54K BeadChip genotypes of ~1000 Israeli Holstein bulls: (i) the long-range haplotype test, which searches for structural evidence resulting from selective sweep, and (ii) direct analysis of the changes in haplotypes frequencies over time combined with linkage disequilibrium blocks haplotype-based association analysis. Ten traits were analyzed: the PD07 Israeli selection index, milk, milk fat, % fat, milk protein, % protein, somatic cell score, female fertility, milk production persistency and herd life.

A simple method for genomic selection of moderately sized dairy cattle populations.

An efficient algorithm for genomic selection of moderately sized populations based on single nucleotide polymorphism chip technology is described. A total of 995 Israeli Holstein bulls with genetic evaluations based on daughter records were genotyped for either the BovineSNP50 BeadChip or the BovineSNP50 v2 BeadChip. Milk, fat, protein, somatic cell score, female fertility, milk production persistency and herd-life were analyzed.

Fine Mapping of a QTL for Fertility on BTA7 and Its Association With a CNV in the Israeli Holsteins.

A quantitative trait locus (QTL) affecting female fertility, scored as the inverse of the number of inseminations to conception, on Bos taurus chromosome 7 was detected by a daughter design analysis of the Israeli Holstein population (P < 0.0003). Sires of five of the 10 families analyzed were heterozygous for the QTL.

Season-induced changes in bovine sperm motility following a freeze-thaw procedure.

Decreased conception rate of dairy cows in the summer is mainly associated with the deleterious effects of environmental thermal stress on the female reproductive tract. Here, we suggest that decreased reproductive performance might be partially due to inferior-quality semen. Semen from five representative bulls was collected in summer (August to September) and winter (December to January) and evaluated with a computerized sperm-quality analyzer for bulls (SQA-Vb).

Differential expression of ruminant ZNF496 variants: Association with quantitative trait locus affecting bovine milk concentration and fertility.

A single nucleotide polymorphism in the intergenic region upstream of the ZNF496 gene on Bos taurus chromosome 7 displayed significant population-wide linkage disequilibrium with milk protein percentage in the Israeli Holstein population. The frequency of the allele associated with increased protein concentration was 10%. This single nucleotide polymorphism was located in the promoter region from which a 10-exon transcript of the bovine and the ovine ZNF496 genes are transcribed.

Analysis of copy loss and gain variations in Holstein cattle autosomes using BeadChip SNPs.

Background: Copy number variation (CNV) has been recently identified in human and other mammalian genomes, and there is a growing awareness of CNV's potential as a major source for heritable variation in complex traits. Genomic selection is a newly developed tool based on the estimation of breeding values for quantitative traits through the use of genome-wide genotyping of SNPs. Over 30,000 Holstein bulls have been genotyped with the Illumina BovineSNP50 BeadChip, which includes 54,001 SNPs (~SNP/50,000 bp), some of which fall within CNV regions.

Factors affecting fertility of dairy cows in Israel.

Unlabelled: The objectives of this review are to describe the reproductive parameters monitored in Israeli dairy herds and to evaluate their changes in recent years. Eighty percent of the cows and 70% of the farms use the Israel Cattle Breeders' Association Herdbook and about 50% of them use pedometry systems. Intensive herd medicine is practiced in 80% of the herds by Hachaklait Veterinary Services Ltd.

Paternity validation and estimation of genotyping error rate for the BovineSNP50 BeadChip.

Incorrect paternity assignment in cattle can have a major effect on rates of genetic gain. Of the 576 Israeli Holstein bulls genotyped by the BovineSNP50 BeadChip, there were 204 bulls for which the father was also genotyped. The results of 38 828 valid single nucleotide polymorphisms (SNPs) were used to validate paternity, determine the genotyping error rates and determine criteria enabling deletion of defective SNPs from further analysis.

Double freezing of bovine semen.

Fertility of bull spermatozoa cryopreserved in large volume by directional freezing technique, thawed, repackaged in straws and refrozen over liquid nitrogen vapor (double freezing, DF) was compared to conventional single freezing in straws (CF). Semen was collected from 6 bulls, 4 of which were selected for the field trial. Each semen collection was split into two parts, one frozen by CF and the other by DF.

Association between seasonal changes in fatty-acid composition, expression of VLDL receptor and bovine sperm quality.

Reduced reproductive performance of dairy cows during the summer is often associated with elevated temperature. Semen collected and cryopreserved during the summer may be of low quality and might contribute to the compromised fertility of dairy cows during this season. The present study examined the association between seasonality, semen quality and its potential to survive cryopreservation.

Successful pregnancies in cows following double freezing of a large volume of semen.

The objective of the following paper is to describe a new technology for large volume and double freezing of semen in 12 mL test tubes. Semen from two different bulls was frozen with a new technique using 12 mL test tubes and was refrozen after thawing in mini straws. All freezing was done in a "Multi thermal gradient" (MTG) freezing apparatus, which moves the container at a constant velocity (V) through a thermal gradient (G) producing a controlled cooling rate B = (G) x (V).

The effect of liposomes on thermotropic membrane phase transitions of bovine spermatozoa and oocytes: implications for reducing chilling sensitivity.

We have examined the effects of combinations between egg-phosphatidylcholine (EPC) or dipalmitoylphosphatidylcholine (DPPC) liposomes with either bovine spermatozoa or oocytes on cellular chilling sensitivity, lipid phase transition temperature (T(m)), and the ability of the oocytes to develop to the blastocyst stage. Spermatozoa and oocytes were exposed to EPC and DPPC liposomes at various temperatures (spermatozoa: 4, 12, 16, and 25 degrees C; oocytes: 4, 16, and 32 degrees C). The membrane integrity of the spermatozoa-control group decreased significantly following exposure to 16 or 12 degrees C, compared to ambient temperature (25 degrees C).

Does membrane lipid profile explain chilling sensitivity and membrane lipid phase transition of spermatozoa and oocytes?

Ram, fowl and bee spermatozoa, and oocytes of cows and zebrafish were used to study lipid membrane profiles, chilling sensitivity and lipid-phase transitions. The integrity of the membranes was determined by carboxyfluorescein diacetate (CFDA) staining following exposure for 15 minutes to low temperatures. Ram and fowl spermatozoa showed different degrees of loss of membrane integrity.