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The experiment described in this research communication aimed to compare the immunological traits of Simmental (sire) × Holstein (dam) crossbred cows with the two parental breeds in the peripartum and early lactation period and to estimate the effects of heterosis for these traits. Flow cytometric evaluation of leukocyte subpopulations was assessed in 16 Crossbred (CR), 8 Holstein (HO) and 8 Simmental (SI) cows. Estimated average values of innate and adaptive immune cells showed statistically significant differences between the crossbred cows and parental breeds. Interestingly, the most relevant differences between the three groups related to adaptive immune cells. In particular, the CR cows showed a lower percentage of CD3+ T lymphocytes compared with the SI group (P < 0.0001) and the highest proportions of CD21+ B lymphocytes among the three groups (P < 0.0001). Furthermore, we found the highest positive value of heterosis for the CD21+ B lymphocytes (7.0) and the lowest negative value for CD3+ T lymphocytes (−4.8) in F1 derived population. It seems reasonable to believe that these differences could affect immune function of crossbred cows.

The aim of the research reported in this paper was to evaluate plasma concentrations of energy, oxidative and inflammatory biomarkers of Simmental (sire) × Holstein (dam) crossbred cows, in comparison with the two parental breeds during the peripartal and early lactation periods and to estimate the effects of heterosis for these traits. Thirty-three animals, managed under the same conditions, 8 Simmental (SI), 9 Holstein (HO) and 16 crossbred (CR) cows were enrolled in this study. Glucose, non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), total protein, albumin, creatinine and urea were determined in blood sampled at six different time points (30 ± 3 and 15 ± 3 d before the expected calving date, at calving and 15, 30 and 60 d after calving). Furthermore, derived reactive oxygen metabolites (d-ROMs), biological antioxidant potential (BAP), interleukin-6 (IL-6), haptoglobin (Hp) and serum amyloid A protein (SAA) were determined to evaluate inflammatory and oxidative status. Results showed that the CR group had significantly lower average values of glucose and NEFA when compared to HO group; signifcantly lower values of urea than SI group and significantly higher values of creatinine than HO. Furthermore, CR cows showed the lowest average value of d-ROMs with respect to SI and HO parental breeds. Finally, the average value of haptoglobin was significantly lower in CR and HO groups, when compared to SI group. As for the heterosis we found the highest (positive) percentage for CK (98%) and BAP (47%) and the lowest (negative) percentage for OSi (−75%) and d-ROMs (−39%). A negative percentage was also found for the glucose (−11%) and NEFA (−20%) toward the Simmental parental breed. Our results suggest a different response among the three genetic groups during the peripartal and early lactation periods. In particular, CR and SI cows seem more adaptable regarding energy metabolism and oxidative status. Heterosis led to a positive effect on those parameters in Simmental (sire) × Holstein (dam) crossbred cows F1 population (50% Simmental and 50% Holstein).

Monocytes are bone marrow derived innate myeloid cells that circulate in the blood and play important roles in infection and inflammation. As part of the mononuclear phagocytic system, monocytes provide innate effector functions, support the adaptive immune response, and play a role in the maintenance of tissue homeostasis. In addition to their role in sensing pathogen-associated molecular patterns using several pattern recognition receptors, monocytes are characterized by their ability to ingest and kill microbes, to produce cytokines and chemokines, and to present antigens to T cells. For a long time, monocytes have been considered as a homogenous cell population, characterized by the expression of CD14, the receptor of lipopolysaccharide. Studies in several species have shown that the monocyte population consists of phenotypically and functionally different cell subsets. In this review, we report a comprehensive phenotyping of monocyte subsets in cattle. In addition, the most characterizing cell markers and gating strategies for detailed immunophenotyping of bovine monocyte subsets are discussed.

Interleukin 8 (IL8) is a major mediator of the innate immune response. Polymorphisms in this gene are associated with susceptibility to inflammatory disease in humans. Two major promoter polymorphic haplotypes (IL8-h1 and IL8-h2) segregating in cattle populations have shown a significant effect on the immune response profile in calves but their implications for transition cow immunity have not been established. The aims of this study were to assess functional relevance of the IL8 haplotypes on the immunological traits of periparturient cows (n = 32) belonging to three genetic groups: Holstein (HO), Simmental (SI) and their crosses (CR) and to evaluate the frequency of IL8 haplotypes in the HO (dairy) and SI (dual purpose) pure breeds. IL8 haplotypes showed a significant effect on circulating number of both T helper lymphocytes (P = 0.0133) and T cytotoxic lymphocytes (P = 0.0024). Differences in percentage of CD14+ monocytes and T lymphocyte subsets were found between haplotype groups at different time points. Plasma concentrations of Serum Amyloid A (SAA) and Haptoglobin (Hp) were enhanced at calving in IL8-h2 (P = 0.0019, P = 0.0029) and IL8-het (P = 0.050 and P = 0.052) respectively, compared with IL8-h1 cows. In contrast, significantly lower levels of reactive oxygen metabolites (d-ROMs) activation were identified in IL8-h2 and IL8-het cows after calving compared with IL8-h1 cows. Furthermore, genotyping results showed that SI cows have a high frequency of the homozygous IL8-h2 haplotype compared to the HO cows (87.5 % vs 40 %) which reflects the different selective pressure between the two pure breeds. In conclusion, our preliminary data suggests that IL8 promoter haplotype is associated with significant and dynamic changes in immunological traits during peripartum and early lactation period. Future work will focus on a more comprehensive assessment of immune changes in additional cows.

The identification of cross-reactive monoclonal antibodies (mAbs) that recognize orthologous leukocyte differentiation molecules (LDM) in buffaloes has overcome a major impediment limiting research on the immune response to pathogens and development of vaccines. As reported, two pilot trials were conducted to accomplish two objectives: (1) demonstrate that multiparameter flow cytometry can be conducted equally well in buffalo with mAbs directly and indirectly labeled with fluorochromes in research and (2) flow cytometry can be used to compare and extend studies on diseases of economic importance to buffalo using bovine viral diarrhea virus (BVDV) as a model pathogen. Pregnant buffalo cows were infected with BVDV-1 at 81 (trial 1) and 203 (trial 2) days post artificial insemination and flow cytometric evaluations were performed at 0, 3, 4, and 14 days after infection (dpi). Fluorochrome conjugated mAbs were used in trial 1, and fluorochrome conjugated goat isotype specific anti-mouse antibodies were used to label mAbs in trial 2. Flow cytometric analysis revealed a transient lymphopenia occurs during the 1st days following infection similar to lymphopenia reported in cattle. In particular, significant differences were observed between pre- and post-infection absolute values of T lymphocytes (−56%, P < 0.01). CD21+ B lymphocytes (−65%, P = 0.04), and Natural Killer cells (−72%, P < 0.001). No significant differences were observed in monocytes and neutrophil absolute values, or the CD4:CD8 ratio. Animal health status was followed until 15 days after calving. No clinical signs of infection were observed during the evaluation period, however, animals in trial 1 developed complications later the infection. One cow aborted at 57 days post-infection, the second cow developed a prolapse a day after calving and died. These two animals also showed a more pronounced lymphopenia in comparison with animals infected at 203 days of pregnancy (e.g., −77 vs. −22% T lymphocytes at 3 dpi, respectively). The pilot studies have demonstrated that it is possible to use multicolour multiparameter flow cytometry to study the immune response to pathogens affecting the health of buffalo.

Flow cytometry is a powerful technology used in many fields of cell biology. It is also used as a routine method to count somatic cells in milk and to characterize bovine milk leukocytes. In this study, we used flow cytometry to simultaneously assess the viability, the percentage of the single subsets of leukocytes and to quantify the expression of CD11b, an immunological marker of cell activation status. Immunological markers were then related with on farm recorded parameters as milk electrical conductivity (MEC) and average milk flow rate (MFR). Composite milk samples were collected from 43 cows, nine of which had naturally infected udders and 34 of which had no infected udders. First, the milk samples were classified according to bacteriological test in positive and negative. The results showed that the negative samples to bacteriological test had: (i) significantly higher percentages of live lymphocytes, (ii) significantly lower percentages of CD11b+ leukocytes, (iii) significantly lower MEC and higher MFR values. Then, samples were classified in three groups according to somatic cell count (SCC): Group A (n = 15), samples with SCC &le, 100,000 cells/mL, all negative to bacteriological analysis, Group B (n = 11), samples with 100,000 &lt, SCC &lt, 300,000 cells/m, with four samples positive to bacteriological analysis, Group C (n = 17), samples with SCC &ge, 300,000 cell/mL with five samples positive to bacteriological analysis. Multivariate discriminant analysis was used to verify which flow cytometry immunological markers and on farm recorded parameters could better discriminate among the different groups of SCCs. Linear discriminant analysis (LDA) indicated that 5 of the 10 parameters could best be used to reveal the differences between positive and negative samples among the considered groups of SCCs. Furthermore, the Canonical discriminant analysis (CDA) indicated that composite milk samples with different SCC and infection status were clearly separated from each other in a two-dimensional space. In conclusion, the study highlighted that: (1) the conventional flow cytometry analysis applied on milk samples is a useful tool to investigate immunological parameters as potential indicators of udder health, (2) the combined evaluation of live milk leukocytes and recorded farm parameters could be useful to assess udder health status in dairy cows. The results obtained from this pilot study on few data require new and larger trials to be confirmed.

Cluster of differentiation 4 (CD4) is the accessory protein non-covalently bounded to T cell receptor (TCR) that recognize an invariant region of MHC class II on antigen presenting cell (APC). Its cytoplasmic tail, physically associated with a protein tyrosine kinase, is important in the activation of helper/inducer T (TH) lymphocytes. The anti-bovine CD4 monoclonal antibody (mAb) CC8 is a clone usefully used in flow cytometry assay in the last 20 years and no anomalous labelling has been described in previous reports. The aim of this study was to investigate the lack and reduced binding of clone CC8 to TH lymphocytes in three different breeds of dairy cattle: Italian Friesian (FRI), Pezzata Rossa Friulana (PRI) and their crossbreed (MET). Two unexpected flow cytometric phenotypes were found: CC8+ (reduced labelling) in 25%, 35% and 15% of the animals in the three breeds respectively, and CC8− (complete lack of labelling) in 15% of PRI cows. The complete sequencing of CD4 coding region (CDS) has allowed to identify two new missense mutations in the exon 5: Q306H and K310 N associated with the two phenotypes. A further new synonymous mutation (g.103634725 G > A) was found in exon 6. Further studies are needed to understand the effects of the news mutations, but these results demonstrate that flow cytometry is a powerful tool to discover polymorphic determinants of antigens involved in the immune responses.

Experimental evidences support a direct role for leptin in immunity. Besides controlling food intake and energy expenditure, leptin was reported to be involved in the regulation of the immune system in ruminants. The aim of this work was to highlight the expression of leptin receptor (LEPR) on Bubalus bubalis immune cells using a multi-approach assessment: flow cytometry, confocal microscopy and gene expression analysis. Flow cytometric analysis of LEPR expression showed that peripheral blood monocytes were the predominant cells expressing LEPR. This result was corroborated by confocal microscopy and RT-PCR analysis. Moreover, among lymphocytes, LEPR was mainly expressed by B lymphocytes and Natural Killer cells. Evidence of LEPR expression on buffalo blood leukocytes showed to be a good indicator of the responsivity of these cells to leptin, so confirming the involvement of leptin in buffalo immune response.

Poly(ADP-ribosyl)ation (PAR) is a post-translational protein modification catalysed by enzyme member of the poly(ADP-ribose) polymerases (PARPs) family. The activation of several PARPs is triggered by DNA strand breakage and the main PARP enzyme involved in this process is PARP1. Besides its involvement in DNA repair, PARP1 is involved in several cellular processes including transcription, epigenetics, chromatin re-modelling as well as in the maintenance of genomic stability. Moreover, several studies in human and animal models showed PARP1 activation in various inflammatory disorders. The aims of the study were (1) to characterize PARP1 expression in bovine peripheral blood mononuclear cells (PBMC) and (2) to evaluate PAR levels as a potential inflammatory marker in cells isolated from blood and milk samples following different types of infection, including mastitis. Our results show that (i) bovine PBMC express PARP1; (ii) lymphocytes exhibit higher expression of PARP1 than monocytes; (iii) PARP1 and PAR levels were higher in circulating PBMCs of infected cows; (iv) PAR levels were higher in cells isolated from milk with higher Somatic Cell Counts (SCC > 100,000 cells/mL) than in cells from milk with low SCCs. In conclusion, these findings suggest that PARP1 is activated during mastitis, which may prove to be a useful biomarker of mastitis.

Camouflage is common throughout the phylogenetic tree and is largely used to minimize detection by predator or prey. Cephalopods, and in particular Sepia officinalis cuttlefish, are common models for camouflage studies. Predator avoidance behaviour is particularly important in this group of soft-bodied animals that lack significant physical defences. While previous studies have suggested that immobile cephalopods selectively camouflage to objects in their immediate surroundings, the camouflage characteristics of cuttlefish during movement are largely unknown. In a heterogenic environment, the visual background and substrate feature changes quickly as the animal swim across it, wherein substrate patch is a distinctive and high contrast patch of substrate in the animal’s trajectory. In the current study, we examine the effect of substrate patch size on cuttlefish camouflage, and specifically the minimal size of an object for eliciting intensity matching response while moving. Our results indicated that substrate patch size has a positive effect on animal’s reflectance change, and that the threshold patch size resulting in camouflage response falls between 10 and 19 cm (width). These observations suggest that the animal’s length (7.2-12.3 cm mantle length in our case) serves as a possible threshold filter below which objects are considered irrelevant for camouflage, reducing the frequency of reflectance changes - which may lead to detection. Accordingly, we have constructed a computational model capturing the main features of the observed camouflaging behaviour, provided for cephalopod camouflage during movement.

International audience; While octopuses are mostly benthic animals, and squid prefer the open waters, cuttlefish present a special intermediate stage. Although their body structure resembles that of a squid, in many cases their behavior is mostly benthic. To test cuttlefish's preference in the use of space, we trained juvenile Sepia gibba and Sepia officinalis cuttlefish to reach a shelter at the opposite side of a tank. Afterwards, rock barriers were placed between the starting point and the shelter. In one experiment, direct paths were available both through the sand and over the rocks. In a second experiment the direct path was blocked by small rocks requiring a short detour to by-pass. In the third experiment instead, the only direct path available was over the rocks; or else to reach the goal via an exclusively horizontal path a longer detour would have to be selected. We showed that cuttlefish prefer to move horizontally when a direct route or a short detour path is available close to the ground; however when faced with significant obstacles they can and would preferentially choose a more direct path requiring a vertical movement over a longer exclusively horizontal path. Therefore, cuttlefish appear to be predominantly benthic dwellers that prefer to stay near the bottom. Nonetheless, they do view and utilize the vertical space in their daily movements where it plays a role in night foraging, obstacles negotiation and movement in their home-range.

Leptin has a pleiotropic effect on regulating appetite, energy metabolism, growth, reproduction, body composition and immunity. This property supports leptin and its receptor as candidate genes for evaluating genetic polymorphisms to associate with growth, milk yield and other economic traits. The aim of this study is to characterize the leptin receptor gene in Bubalus bubalis, to identify single-nucleotide polymorphism (SNP) sites in different coding and non-coding regions and to analyse potential associations between SNPs identified and the body measurements traits of growing buffalo heifers. A group of 64 animals were genotyped by direct sequencing and twenty-eight SNPs were detected. A sequence analysis revealed the presence of nine interesting SNPs in gene sequence. The association analysis of polymorphisms with the body measurements traits of growing buffalo heifers shows significant statistical effects on chest depth and sacrum height. Therefore according to the results obtained from this study, the leptin receptor gene appears to have potential effects on the body measurement traits of Bubalus bubalis.

SLC11A1 (solute carrier family 11 member 1 protein) gene influences the initial phase of bacterial cellular infections through macrophage activation. Recent literature on buffalo has attempted to associate the genotype of the polymorphic microsatellite located in the 3'untranslated region (3'UTR) of the gene, with either susceptibility to brucellosis or with improved macrophage function. Carriers of the (GT)16 allele have been reported to be resistant to brucellosis. In this study we analyzed the steady-state level of SLC11A1 expression in a serologically negative herd of 26 animals differing by the number of (GT)n microsatellite repeats by using a reverse transcriptase quantitative real-time polymerase chain reaction approach. We evaluated five different reference genes, which had not been reported previously, for use in gene expression experiments in buffalo blood. However, we did not find any significant difference between buffalo carriers of the different microsatellite alleles, with respect to SLC11A1 expression in whole blood or in blood fractions [peripheral blood mononuclear cells (PBMC) and polymorphonuclear leukocytes/granulocytes (PMN/G)]. Conversely, there was a difference between the blood fractions in their SLC11A1 expression levels, with the PMN/G fraction having a higher expression level than the PBMC fraction (P0.015).

To date, only a few SNP in the leptin receptor gene have been detected and analyzed while the leptin gene has been extensively characterized and several polymorphisms were detected and associated to functional and productive traits in cattle. In this work, for the first time, the bovine leptin receptor gene was fully characterized by sequencing the whole coding region and part of the 5’ flanking region. A group of 95 Holstein cows was genotyped in order to search for SNP at both the LEPR and LEP genes, and to associate them with milk and morphological traits. Nine novel SNP in the leptin receptor gene and one novel SNP in the leptin gene were detected. Four SNP of the leptin receptor gene and one SNP of leptin gene showed a significant effect on one or more analyzed traits, and, in all cases, the greatest effect was observed on fat content. This study provided knowledge of the existence of further polymorphisms in the leptin receptor and leptin genes that have an influence on some important economic traits.

Insulin-like growth factor I (IGF-I) plays an important role in mammary growth and function. We detected two novel SNPs in the 5′UTR of the IGF-I gene: g.855G>C and g.857G>A of locus X69472, and genotyped 103 sheep of three breeds at the identified polymorphisms. The same animals were genotyped at a previously reported SNP (g.271C>T; accession X69473) located in exon 3. From the SNPs we built 4 haplotypes. We calculated lactation persistency from test day records of the genotyped animals as the ratio of milk (kg), fat (g) and protein (g) yield from day 86 to 170 of machine milking to yields during the first 85 days of machine milking. We estimated allele substitution effect on persistency for each SNP and haplotype. We found that allele T of SNP g.271C>T and haplotype [G;T] had a positive effect on maintaining a constant yield level during lactation. The improvement of lactation persistency could be highly beneficial to the sustainable use of local breeds.

One hundred seven cattles of four breeds (Holstein–Friesian, Jersey, Valdostana and Piedmontese) were genotyped at the DGAT1 K232A and the SCD1 A293V variants, as well as at 7 SNPs of the GHR gene, that were used to construct 14 GHR haplotypes. Allele frequency at most SNPs, and GHR haplotype frequencies highly differed between breeds. The effect of each SNP and haplotype was associated to milk production traits. The consistent effect of the 232K allele of DGAT1 on the increase of fat and protein content was confirmed in the Holstein and the Jersey, while this allele is missing in the Valdostana and rare (0.03) in the Piedmontese. SCD1 A293V variant showed no effect on either milk yield or fat and protein content. The positive effect of GHR F279Y variant on milk fat and protein content, although much weaker than the effect of DGAT1, was confirmed. The combination of the GHR SNPs into haplotypes seems to improve the association, likely for the interaction of variant F279Y with a SNP in the GHR gene promoter.

Summary The objective of this work was to characterize the complete coding region of the ovine acyl CoA:diacylglycerol acyltransferase 1 (DGAT1) gene of three Italian sheep breeds: Sarda, Altamurana and Gentile di Puglia. Characterization was accomplished by direct sequencing of 8676 bp of the relevant DNA, including introns and partial 5¢ and 3¢ untranslated regions (UTRs). We detected five novel SNPs; one SNP (g.5553C>T) is located in intron 2, has similar frequencies in the three breeds and showed a negative association with milk fat content. More interesting is an SNP in the 5¢ UTR (g.127C>A), the occurrence of which is rare in the higher milk-fat breeds (Altamurana and Gentile di Puglia); it is located in the core sequence of Sp1, a putative binding site of transcription factors. This SNP showed a significant negative association with milk fat content in the Sarda sheep. Because DGAT1 plays a fundamental role in triacylglycerol synthesis, the novel detected SNP in the 5¢ UTR of the DGAT1 gene might explain, at least partially, the variation of fat content in the milk of Sarda sheep.

Development of DNA technologies makes today possible implementation of conventional beef traceability systems with molecular methods. In the recent past, microsatellites have been the most used marker for individual assignment, however single nucleotide polymorphisms (SNPs) is now replacing them. With the aim to provide a set of SNPs useful for bovine meat traceability we have tested 63 SNPs for the ability to identify single individuals in six European cattle breeds. Eighteen highly informative SNPs located in different genes, have been selected. By using this panel of SNPs the probability that one individual is incorrectly assigned ranges from 1.39 to 0.07 out of 1 million, depending on the breed.

Acetyl-CoA carboxylase-alpha (ACACA) is the major regulatory enzyme of fatty acid biosynthesis. We have sequenced a fragment of Promoter III of the ovine ACACA gene in 211 goats of 5 breeds. The caprine sequence showed a high nucleotide identity (99%) with the ovine. We have identified 3 novel single nucleotide polymorphisms (SNPs) that fall in the core sequence of putative binding sites of transcription factors and have lower allele frequency than the wild type in all breeds. We evaluated the allele substitution effect of the SNPs on milk traits in the Saanen and the Local Grey breeds. Results from this study show that the mutations are associated with fat yield.

The world is three-dimensional; hence, even surface-bound animals need to learn vertical spatial information. Separate encoding of vertical and horizontal spatial information seems to be the common strategy regardless of the locomotory style of animals. However, a difference seems to exist in the way freely moving species, such as fish, learn and integrate spatial information as opposed to surface-bound species, which prioritize the horizontal dimension and encode it with a higher resolution. Thus, the locomotory style of an animal may shape how spatial information is learned and prioritized. An alternative hypothesis relates the preference for vertical information to the ability to sense hydrostatic pressure, a prominent cue unique to this dimension. Cuttlefish are mostly benthic animals, but they can move freely in a volume. Therefore, they present an optimal model to examine these hypotheses. We tested whether cuttlefish could separately recall the vertical and horizontal components of a learned two-dimensional target, and whether they have a preference for vertical or horizontal information. Sepia officinalis cuttlefish were trained to select one of two visual cues set along a 45 deg diagonal. The animals were then tested with the two visual cues arranged in a horizontal, vertical or opposite 45 deg configuration. We found that cuttlefish use vertical and horizontal spatial cues separately, and that they prefer vertical information to horizontal information. We propose that, as in fish, the availability of hydrostatic pressure, combined with the ecological value of vertical movements, determines the importance of vertical information.

Leptin is a protein involved in the regulation of feed intake, fat metabolism, whole body energy balance, reproduction and hematopoiesis. In cattle Leptin gene has been considered a potential QTL influencing several production traits like meat production, milk performance and reproduction. Several studies on bovine leptin gene have found association between polymorphisms and traits like milk yield, feed intake, fat content, carcass and meat quality. With the aim to assess the presence of sequences polymorphisms in the Buffalo leptin gene, we sequenced the entire coding region and part of the introns on a panel of Italian River Buffalos. In this study we identified a new set of SNP (Single Nucleotide Polymorphism) useful for association studies.

NRAMP1 (natural-resistance-associated macrophage protein) gene influences the initial phase of bacterial cellular infections, regulating macrophage activation. Recent literature on buffalo has attempted to associate the genotypes at the polymorphic microsatellite, that is located in the 3'-UTR of the gene, with either susceptibility to brucellosis or improved macrophage function. However, contradictory results were reported. In the present work, we have sequenced the whole coding region, as well as part of the introns and UTRs, of the NRAMP1 gene in 49 Mediterranean buffaloes, including both serologically positive and negative animals to Brucella abortus test. We have detected 12 mutations. Nineteen haplotypes were built from the detected variant alleles, so demonstrating the high variability of this gene in buffalo, but no significant differences in haplotype frequencies were found between serologically positive/negative animals.

In this work, the genetic variation of milk FA was investigated in three different bovine breeds, the Jersey, the Piedmontese and the Valdostana, and at different lactation stages. All animals were genotyped for 21 Single Nucleotide Polymorphisms located within nine candidate genes involved in lipid synthesis: diacylglycerol acyltransferase 1 and 2 (DGAT1, 2); stearoyl-CoA desaturase (SCD); growth hormone receptor (GHR); fatty acid synthase (FASN); acyl-CoA dehydrogenase (ACAD); fatty acid binding protein (FABP4); lipoprotein lipase (LPL); and leptin gene (LEP). The highest milk-fat Jersey breed also showed the highest content of saturated FA. Throughout lactation, the breeds showed a similar variation in the FA, with a decrease in the short-chain, this was accompanied by a general increase in the long chain FA at the end of lactation. The increase in long chain saturated FA was particularly evident in the case of the Jersey. The effect ofSCDgene on the C14 desaturation index was confirmed; theDGAT1gene was polymorphic only in the Jersey breed, but its effect was confirmed only on milk fat content; three further potential candidate genes were identified: first, theFABP4gene, which was found to influence medium and long chain FA in all the breeds, but not the desaturation indices; second, theFASNgene, which was found to influence the amount of PUFA in the Piedmontese and the Valdostana, and third, theLPLgene, which was found to affect fat content in the Piedmontese.

Background Identification of genomic regions that have been targets of selection for phenotypic traits is one of the most challenging areas of research in animal genetics, particularly in livestock where few annotated genes are available. In this study a genome-wide scan using the Illumina SNP50K Beadchip was performed in the attempt to identify genomic regions associated with milk productivity in sheep. The ovine genomic regions encoding putative candidate genes were compared with the corresponding areas in Bos taurus, as the taurine genome is better annotated. Results A total of 100 dairy sheep were genotyped on the Illumina OvineSNP50K Beadchip. The Fisher’s exact test of significance of differences of allele frequency between each pair of the two tails of the distribution of top/worse milk yielders was performed for each marker. The genomic regions where highly divergent milk yielders showed different allele frequencies at consecutive markers was extracted from the OAR v3.1 Ovine (Texel) Genome Assembly, and was compared to the corresponding areas in Bos taurus, allowing the detection of two genes, the Palmdelphin and the Ring finger protein 145. These genes encoded non-synonymous mutations correlated with the marker alleles. Conclusion The innovation of this study was to show that the DNA genotyping with the Illumina SNP50K Beadchip allowed to detect genes, and mutations in the genes, which have not yet been annotated in the livestock under investigation.

Summary No major gene has yet been reported in sheep that explains the variation of milk fat content. The coding region of the acetyl-CoA carboxylase alpha (ACACA) gene, which plays an important role in de novo fatty acid synthesis, had been investigated, but no non-synonymous mutations have been reported. In this study, the genomic regions encoding the three promoters of the ACACA gene were directly sequenced in 264 sheep of three different breeds, and 10 SNPs were identified. Allele frequencies of most SNPs significantly differed (P = 0.05–0.0001) between breeds. The SNPs that potentially altered either gene regulatory elements or putative binding sites of transcription factors were made evident through in silico analysis. The association analysis with milk traits, performed for one SNP of PIII (GenBank AJ292286, g.1330G>T), showed a significant allelic substitution effect (+0.33%, P

A more precise determination of the date of primary rubella infection in pregnancy is obtained by application of the urea denaturation method. Two denaturation buffers containing 6 and 8 M urea were compared for the detection of rubella IgG avidity by enzyme immunoassay. The results demonstrate that IgG avidity detected by 6M urea increases more rapidly, from 16% on the third day to 51% on the 46th day after the rash, than that obtained by 8 M urea, from 13 to 36%. The specific rubella IgG avidity detected by 6 M urea denaturation buffer increased significantly in paired sera obtained at an interval of 15 days. The same samples did not show any significant increase of IgG avidity when an 8 M urea denaturation buffer was used. The use of a mild denaturant such as 6 M urea indicates the presumptive date of primary rubella infection in pregnancy within 2 months of sampling.