Eyal Seroussi

Agricultural Research Organization ARO | aro · Institute of Animal Science

Genetic selection has achieved little progress in reducing mastitis incidence. Mastitis traits are problematic due to the lack of sensitivity of the data and reliance on clinical diagnosis, often missing subclinical cases, and/or on monthly somatic cell count (SCC) measurements. The current measure for mastitis is the lactation average of the somat...

“Livability” was defined as the inverse of the probability of death. The objectives of this study were to estimate the heritability, genetic and phenotypic trends for the livability of Israeli Holstein cows; estimate the genetic and environmental correlations between livability and the nine traits included in the Israeli breeding index; estimate th...

In dairy cattle, identifying polymorphisms that contribute to complex economical traits such as residual feed intake (RFI) is challenging and demands accurate genotyping. In this study, we compared imputed genotypes (n = 192 cows) to those obtained using the TaqMan and high-resolution melting (HRM) methods (n = 114 cows), for mutations in the FABP4...

In vertebrates, mainly single genes with an allele ratio of 1:1 trigger sex-determination (SD), leading to initial equal sex-ratios. Such genes are designated master-key regulators (MKRs) and are frequently associated with DNA structural variations, such as copy-number variation and null-alleles. Most MKR knowledge comes from fish, especially cichl...

Oreochromis niloticus has been used as a reference genome for studies of tilapia sex determination (SD) revealing segregating genetic loci on linkage groups (LGs) 1, 3, and 23. The master key regulator genes (MKR) underlying the SD regions on LGs 3 and 23 have been already found. To identify the MKR in fish that segregate for the LG1 XX/XY SD-syste...

Background Copy number variation (CNV) has been routinely studied using bulk-cell sequencing. However, CNV is not well studied on the single-cell level except for humans and a few model organisms. Results We sequenced 143 single sperms of two Holstein bulls, from which we predicted CNV events using 14 single sperms with deep sequencing. We then co...

All‐female culture of sturgeon is essential for efficient caviar production. However, Russian sturgeon (Acipenser gueldenstaedtii) does not exhibit external sexual dimorphism, and therefore, commercial farms apply gonadal endoscopy or ultrasound at the earliest age of 4–5 years to separate the sexes, with ~90% accuracy. Recently, a dominant genomic...

Microarray-based genomic selection is a central tool to increase the genetic gain of economically significant traits in dairy cattle. Yet, the effectivity of this tool is slightly limited, as estimates based on genotype data only partially explain the observed heritability. In the analysis of the genomes of 17 Israeli Holstein bulls, we compared ge...

Background Meiotic recombination is one of the important phenomena contributing to gamete genome diversity. However, except for human and a few model organisms, it is not well studied in livestock, including cattle. Results To investigate their distributions in the cattle sperm genome, we sequenced 143 single sperms from two Holstein bulls. We map...

Oreochromis fishes exhibit variability of sex-determination (SD) genes whose characterization contributes to understanding of the sex differentiation network, and to effective tilapia farming, which requires all-male culture. However, O. niloticus (On) amh is the only master-key regulator (MKR) of SD that has been mapped (XY/XX SD-system on LG23)....

Crossing Oreochromis niloticus (On) females with Oreochromis aureus (Oa) males results in all‐male progeny that are essential for effective tilapia farming. However, a reproductive barrier between these species limits mating and mass‐fry production. One approach to overcoming this barrier is to select parental stocks of mixed genetic backgrounds, w...

Determination of the relative copy numbers of mixed molecular species in nucleic acid samples is often the objective of biological experiments, including Single-Nucleotide Polymorphism (SNP), indel and gene copy-number characterization, and quantification of CRISPR-Cas9 base editing, cytosine methylation, and RNA editing. Standard dye-terminator ch...

Various master key regulators (MKRs) that control a binary switch of sex determination (SD) have been found in fish; these provide an excellent model for the study of vertebrate genetic SD. The SD region in flathead grey mullet has been previously mapped to a 1 Mbp region harboring 27 genes, of which one is follicle-stimulating hormone receptor (fs...

Various master key regulators (MKRs) that control a binary switch of sex determination (SD) have been found in fish; these provide an excellent model for the study of vertebrate genetic SD. The SD region in flathead grey mullet has been previously mapped to a 1 Mbp region harboring 27 genes, of which one is Follicle-stimulating hormone receptor (fs...

Differentiation of cells by flow cytometry provides informative somatic cell counts (SCCs) that allow analyzing leukocyte population patterns in udder infections of different etiologies. Postulating that this approach also enhances the statistical power to detect genetic variants linked to cell levels in milk of healthy mammary glands, we used mono...

Flathead gray mullet (Mugil cephalus) is a cosmopolitan mugilid species popular in fishery and aquaculture with an economic preference for all-female population. However, it displays neither sexual dimorphisms nor heteromorphic sex chromosomes. We have previously presented a microsatellite-based linkage map for this species locating a single sex de...

Sex determination (SD) mechanisms are ancient and conserved, yet much diversity is exhibited in primary sex-determining signals that trigger male or female development. In O. niloticus, SD is associated with a male-specific locus on linkage group (LG) 23 which harbors the Y-linked Anti-Müllerian hormone (amh) gene, and a truncated duplication, deno...

Discovery of the satiety hormone leptin in 1994 and its characterization in mammals provided a key tool to deciphering the complex mechanism governing adipose tissue regulation of appetite and energy expenditure. Surprisingly, despite the perfectly logical notion of an energy-storing tissue announcing the amount of fat stores using leptin signaling...

Poecilia reticulata is one of the most popular ornamental fish species with a higher demand for males due to their large colorful fins. The objectives of this study were mapping of the sex-determining (SD) region on linkage group 12 of guppy, and identification of a sex specific marker. We generated eight polymorphic microsatellite markers distribu...

The Thai-Chitralada strain originates from Egypt and was transferred to Japan. From there a stock of 50 fish were introduced to the Royal Chitralada Palace in Thailand. The commercially cultured strain of Nile tilapia O. niloticus in Thailand, Thai-Chitralada, possesses desirable traits for aquaculture, such as high growth rate integrated with reas...

In mammals, leptin and tumor-necrosis factor (TNF) are prominent interacting adipokines mediating appetite control and insulin sensitivity. While TNF pleiotropically functions in immune defense and cell survival, leptin is largely confined to signaling energy stores in adipocytes. Knowledge about the function of avian leptin and TNF is limited and...

In mammals, leptin and tumor-necrosis factor (TNF) are prominent interacting adipokines mediating appetite control and insulin sensitivity. While TNF pleiotropically functions in immune defense and cell survival, leptin is largely confined to signaling energy stores in adipocytes. Knowledge about the function of avian leptin and TNF is limited and...

Abstract Background Crossover localization during meiotic recombination is mediated by the fast-evolving zinc-finger (ZnF) domain of gene PRDM9. To study its impact on dairy cattle performance, we compared its genetic variation between the relatively small Israeli (IL) Holsteins and the North American (US) Holsteins that count millions. Results Ini...

Background Copy number variations (CNVs) are structural variants consisting of large-scale insertions and deletions of genomic fragments. Exploring CNVs and estimating their effects on phenotypes are useful for genome selection but remain challenging in the livestock. Results We identified 1043 CNV regions (CNVRs) from array comparative genomic hy...

Recent findings have indicated that secreted phospholipases A2 (sPLA2s) have anti-inflammatory functions, including relief of symptoms in a mouse model of mastitis. This prompted us to investigate the therapeutic application of sPLA2, PLA2G1B, for bovine mastitis. Initial testing of PLA2G1B's effect on bovine mammary epithelial cell (bMEC) line PS...

ARRIVE guidelines checklist. A checklist for reporting in vivo experiments of this animal research (experiments 1–3). (PDF)

Effective farming of tilapia requires all-male culture, characterized by uniformity and high growth rate. Males of O. aureus (Oa) and females of O. niloticus (On) produce all-male offspring, but there is a behavioral reproductive barrier between the two species that prevents mass production. In crosses between Oa and On broodstocks, few hybrid fema...

Background: Crossover generated by meiotic recombination is a fundamental event that facilitates meiosis and sexual reproduction. Comparative studies have shown wide variation in recombination rate among species, but the characterization of recombination features between cattle breeds has not yet been performed. Cattle populations in North America...

Abstract Background The mammalian adipose tissue plays a central role in energy-balance control, whereas the avian visceral fat hardly expresses leptin, the key adipokine in mammals. Therefore, to assess the endocrine role of adipose tissue in birds, we compared the transcriptome and proteome between two metabolically different types of chickens, b...

BACKGROUND: The mammalian adipose tissue plays a central role in energy-balance control, whereas the avian visceral fat hardly expresses leptin, the key adipokine in mammals. Therefore, to assess the endocrine role of adipose tissue in birds, we compared the transcriptome and proteome between two metabolically different types of chickens, broilers...

The Lake Tiberias (Sea of Galilee) grey mullet (Mugil cephalus) population originates from translocated wild-caught, or hatchery-reared, fish. The aim of the study was to identify the taxonomic status and stock origin of a sample of 32 mullet individuals caught in the Sea of Galilee, based on the mitochondrial Cytochrome Oxidase I (COI) sequence an...

Background Sheep production in Israel has improved by crossing the fat-tailed local Awassi breed with the East Friesian and later, with the Booroola Merino breed, which led to the formation of the highly prolific Afec-Assaf strain. This strain differs from its parental Awassi breed in morphological traits such as tail and horn size, coat pigmentati...

Background Misidentification of the chicken leptin gene has hampered research of leptin signaling in this species for almost two decades. Recently, the genuine leptin gene with a GC-rich (~70%) repetitive-sequence content was identified in the chicken genome but without indicating its genomic position. This suggests that such GC-rich sequences are...

Correction: After the publication of this work [1] an error was noticed in one of the author surnames. The author name Leif Anderson should be spelt as Leif Andersson.

Ruminants sustain a long-lasting obligatory relationship with their rumen microbiome dating back 50 million years. In this unique host-microbiome relationship, the host’s ability to digest its feed is completely dependent on its coevolved microbiome. This extraordinary alliance raises questions regarding the dependent relationship between ruminants...

Through RNA-Seq analyses, we identified 137 genes that are missing in chicken, including the long-sought-after nephrin and tumor necrosis factor genes. These genes tended to cluster in GC-rich regions that have poor coverage in genome sequence databases. Hence, the occurrence of syntenic groups of vertebrate genes that have not been observed in Ave...

Fig. S1. MFOLD output, the complete image of the folded forward template of the amplicon of ACG haplotype. Fig. S2. MFOLD output, the complete image of the folded forward template of the amplicon of ATT haplotype. Fig. S3. MFOLD output, the complete image of the folded forward template of the amplicon of GCG haplotype. Fig. S4. MFOLD output, the...

Calculating peak-height ratios between SNP alleles in sequencing chromatograms is a practical method for estimating their copy-number proportions. However, it is surprising that sequencing DNA from different directions might yield different results. We analyzed three adjacent SNPs within the ovine period circadian-clock 2 (PER2) gene that displayed...

Purpose Applying CNGA3 gene augmentation therapy to cure a novel causative mutation underlying achromatopsia (ACHM) in sheep. Methods Impaired vision that spontaneously appeared in newborn lambs was characterized by behavioral, electroretinographic (ERG), and histologic techniques. Deep-sequencing reads of an affected lamb and an unaffected lamb w...

Elucidation of the sex-determination mechanism in flathead grey mullet (Mugil cephalus) is required to exploit its economic potential by production of genetically determined monosex populations and application of hormonal treatment to parents rather than to the marketed progeny. Our objective was to construct a first-generation linkage map of the M...

More than 20 years after characterization of the key regulator of mammalian energy-balance, leptin, we identified the leptin (LEP) genes of chicken (Gallus gallus) and duck (Anas platyrhynchos). The extreme GC-content (~70%), the location in a genomic region with low-complexity repetitive and palindromic sequence elements, the relatively low sequen...

Background The probable influence of genes and the environment on sex determination in Nile tilapia suggests that it should be regarded as a complex trait. Detection of sex determination genes in tilapia has both scientific and commercial importance. The main objective was to detect genes and microRNAs that were differentially expressed by gender i...

Background A LEP transcript up-regulated in lungs of ducks (Anas platyrhynchos) infected by avian influenza A virus was recently described in the Nature Genetics manuscript that reported the duck genome. In vertebrates, LEP gene symbol is reserved for leptin, the key regulator of energy balance in mammals. Results Launching an extensive search for...

The white grouper (Epinephelus aeneus) is a promising candidate for domestication and aquaculture due to its fast growth, excellent taste and high market price. A linkage map is an essential framework for mapping QTL for economic traits, and study of genome evolution. DNA of a single individual was deep-sequenced and microsatellite markers were ide...

Leptin, the key regulator of mammalian energy-balance, has been at the center of a great controversy in avian biology for the last 15 years, since initial reports of a putative leptin gene (LEP) in chickens. Herein we characterize a novel LEP in rock dove (Columba livia) with low similarity of the predicted protein sequence (30% identity, 47% simil...

The discovery of leptin in 1994 has opened a new era in the study of energy balance control at the molecular level. By informing the brain and other tissues the state of fat stores, leptin plays a key role in the control circuits of both appetite and energy expenditure, thus affecting most if not all of the body’s activities. This discovery in mamm...

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 eq...

Awassi and Assaf are local Israeli sheep breeds with prolificacies of ~1.30 and ~1.65 lambs born/ewe lambing (LB/EL), respectively. Introgressing the B (Booroola) allele of the FecB locus into those breeds led to the formation of prolific strains designated 'Afec Awassi' and 'Afec Assaf', in which lamb production under both intensive and semi-inten...

A chicken gene orthologous to human leptin receptor (LEPR) has been characterized and found to be active in leptin signaling in vitro in response to a variety of recombinant leptins and leptin-containing blood samples. However, the endogenous ligand of chicken LEPR (cLEPR) - the putative chicken leptin - has been reported by us and others to be und...

The recent burst of duplication and divergence of the bovine PLA2G2D genes is considered typical of immune response genes, and it was recently shown that PLA2G2D is abundantly expressed in mouse leukocytes and acts as an immunosuppressive phospholipase. Analysis of 1,143 Holstein bulls indicated that the four common haplotypes spanning PLA2G2D disp...

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. For each bull-by-bull co...

Offspring of a highly inbred gynogenetic line of Oreochromis aureus displayed 12-fold increase in twinning rate compared to the outbred population. Asymmetric conjoined twins, which consist of a normal embryo attached to a malformed-atrophic twin, were frequently encountered in both gynogenetic (90·7%) and outbred (38·2%) embryos. The monozygotic o...

The Tantura F shipwreck, found in Dor lagoon, was dated to the Early Islamic period of Israel (8 th century). Ovoid amphorae found in the shipwreck contained fish bones that were morphologically assigned to the genus Tilapia. A mini-barcode sequence of a 140-bp fragment of the cytochrome oxidase subunit I mitochondrial gene was analyzed for DNA-bas...

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...

In tilapia species, plasma lipoproteins with high electrophoretic mobility function in intra- and intergender communication. Blood samples taken at onset and peak of daily sexual activity from dominant and subordinate Oreochromis niloticus males and females were fractionated by native gel electrophoresis and the fast-migrating proteins were subject...

Polymorphisms in mitochondrial DNA (mtDNA) protein- and tRNA-coding genes were shown to be associated with various diseases in humans as well as with production and reproduction traits in livestock. Alignment of full length mitochondria sequences from the 5 known ovine haplogroups: HA (n = 3), HB (n = 5), HC (n = 3), HD (n = 2), and HE (n = 2; GenB...

Two-plated self-piercing eartags were first developed in the 19th century, but information on their retention rates is scarce. A method is presented that facilitates estimation of eartag retention rate by using a random sample of cows that initially had 2 tags (1 on each ear) placed for identification and at least 1 of which survived. Striving to a...

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. The 95% confidence interval o...

SNPmplexViewersource code. Perl script in text format.

Beef traceability has become mandatory in many regions of the world and is typically achieved through the use of unique numerical codes on ear tags and animal passports. DNA-based traceability uses the animal's own DNA code to identify it and the products derived from it. Using SNaPshot, a primer-extension-based method, a multiplex of 25 SNPs in a...

The hormone leptin is involved in diverse biological processes, including regulation of food intake, body-weight homeostasis and energy balance. Sequence variation in the bovine leptin gene has been found to be associated with variations in carcass fat content and average daily gain, as well as in milk yield, milk somatic cell count and several tra...