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We investigated whether variation of the sheep Growth Hormone Receptor (GHR), Growth Hormone Releasing Hormone Receptor (GHRHR) and Insulin-Like Growth Factor 1 (IGF1) genes were associated with milk coagulation properties (MCP) in sheep. The GHR, GHRHR and IGF1 genes are part of the GH system, which is known to modulate metabolism, growth and reproduction as well as mammogenesis and galactopoiesis in dairy species. A total of 380 dairy Sarda sheep were genotyped for 36 SNPs mapping to these three genes. Traditional MCP were measured as rennet coagulation time (RCT), curd-firming time (k20) and curd firmness at 30 m (a30). Modeling of curd firming over time (CFt) was based on a 60 m lactodynamographic test, generating a total of 240 records of curd firmness (mm) for each milk sample. The model parameters obtained included: the rennet coagulation time as a result of modeling all data available (RCTeq, min); the asymptotic potential value of curd firmness (CFP, mm) at an infinite time; the CF instant rate constant (kCF, %/min); the syneresis instant rate constant (kSR, %/min); the maximum value of CF (CFmax, mm) and the time at achievement of CFmax (tmax, min). Statistical analysis revealed that variation of the GHR gene was significantly associated with RCT, kSR and CFP (P < 0.05). No other significant associations were detected. These findings may be useful for the dairy industry, as well as for selection programs.

One hundred and eighty Anglo-Arabian horses running 1239 races were sampled for the present study. DNA was extracted from the blood and myostatin gene, MSTN, was genotyped. Moreover, prizes won and places were achieved for the 1239 races to perform association analyses between the different genotypes and sport traits. Two SNPs already reported in previous studies regarding the Thoroughbred breed, rs69472472 and rs397152648, were revealed as polymorphic. The linkage disequilibrium analysis investigating the haplotype structure of MSTN did not evidence any association block. Polymorphism at SNP rs397152648, previously known as g.66493737 T&gt, C, significantly influenced sport traits, with heterozygous horses TC showing better results than homozygotes TT. The portion of variance due to the random effect of the individual animal, and the other phenotypic effects of sex, percentage of Arabian blood and race distance, computed together with the genotype at MSTN in the statistical models, exerted a significant influence. Hence, this information is useful to improve knowledge of the genetic profile of Anglo-Arabian horses and a possible selection for better sport performance.

Goat milk and cheese production is continuously increasing and milk composition and coagulation properties (MCP) are useful tools to predict cheesemaking aptitude. The present study was planned to investigate the extension of lactodynamographic analysis up to 60 min in goat milk, to measure the farm and individual factors, and to investigate differences among 6 goat breeds. Daily milk yield (dMY) was recorded and milk samples collected from 1,272 goats reared in 35 farms. Goats were of 6 different breeds: Saanen and Camosciata delle Alpi for the Alpine type, and Murciano-Granadina, Maltese, Sarda, and Sarda Primitiva for the Mediterranean type. Milk composition (fat, protein, lactose, pH; somatic cell score; logarithmic bacterial count) and MCP [rennet coagulation time (RCT, min), curd-firming time (k20, min), curd firmness at 30, 45, and 60 min after rennet addition (a30, a45, and a60, mm)] were recorded, and daily fat and protein yield (dFPY g/d) was calculated as the sum of fat and protein concentration multiplied by the dMY. Data were analyzed using different statistical models to measure the effects of farm, parity, stage of lactation and breed; lastly, the direct and the indirect effect of breed were quantified by comparing the variance of breed from models with or without the inclusion of linear regression of fat, protein, lactose, pH, bacterial, somatic cell counts, and dMY. Orthogonal contrasts were performed to compare least squares means. Almost all traits exhibited high variability, with coefficients of variation between 32 (for RCT) and 63% (for a30). The proportion of variance regarding dMY, dFPY, and milk composition due to the farm was moderate, whereas for MCP it was low, except for a60, at 69%. Parity affected both yield and quality traits of milk, with least squares means of dMY and dFPY showing an increase and RCT and curd firmness traits a decrease from the first to the last parity class. All milk quality traits, excluding fat, were affected by the stage of lactation; RCT and k20 decreased rapidly and a30 was higher from the first to the last part of lactation. Alpine breeds showed the highest dMY and dFPY but Mediterranean the best percentage of protein, fat, and lactose and a shorter k20 and a greater a30. Among the Mediterranean goats, Murciano-Granadina goats had the highest milk yield, fat, and protein contents, whereas Maltese, Sarda, and Sarda Primitiva were characterized by much more favorable technological properties in terms of k20, a30, and a45. In conclusion, as both the farm and individual factors highly influenced milk composition and MCP traits, improvements of these traits should be based both on modifying management and individual goat factors. As expected, several differences were attributable to the breed effect, with the best milk production for the Alpines and milk quality and coagulation for the Mediterranean goats.

Conservation of farm animal genetic resources is of fundamental importance for the study of the relationships among breeds. The aim of this study was to evaluate the usefulness of the nuclear fluorescence inter simple sequence repeat (FISSR) markers in order to shed light on the genetic biodiversity of domestic animals. Two modifications of the original technique were made so as to make it more suitable for routine needs. The modified FISSR protocol was tested on different breeds of goat and donkey from Sardinia, a Mediteranean island known for its biodiversity. The two species are affected by different management problems in Sardinia: goats need a traceability of local products from different breeds, whereas donkeys are drastically reduced in number. The primers used were found to be very informative suggesting that the modified FISSR can be successfully applied in studies on different breeds of animal species without expensive experimentations. This method could be of interest in many geographic regions where there are more breeds of the same species with similar morphological features and different genetic pattern. The strongest point of this method is its low cost. Key words: Fluorescence inter simple sequence repeat (FISSR), biodiversity, genetic variability, goat, donkey.

We investigated whether variation of the sheep Growth Hormone Receptor (GHR), Growth Hormone Releasing Hormone Receptor (GHRHR) and Insulin-Like Growth Factor 1 (IGF1) genes were associated with milk coagulation properties (MCP) in sheep. The GHR, GHRHR and IGF1 genes are part of the GH system, which is known to modulate metabolism, growth and reproduction as well as mammogenesis and galactopoiesis in dairy species. A total of 380 dairy Sarda sheep were genotyped for 36 SNPs mapping to these three genes. Traditional MCP were measured as rennet coagulation time (RCT), curd-firming time (k20) and curd firmness at 30 m (a30). Modeling of curd firming over time (CFt) was based on a 60 m lactodynamographic test, generating a total of 240 records of curd firmness (mm) for each milk sample. The model parameters obtained included: the rennet coagulation time as a result of modeling all data available (RCTeq, min); the asymptotic potential value of curd firmness (CFP, mm) at an infinite time; the CF instant rate constant (kCF, %/min); the syneresis instant rate constant (kSR, %/min); the maximum value of CF (CFmax, mm) and the time at achievement of CFmax (tmax, min). Statistical analysis revealed that variation of the GHR gene was significantly associated with RCT, kSR and CFP (P0.05). No other significant associations were detected. These findings may be useful for the dairy industry, as well as for selection programs.

Several concerns have been raised over the health of animals used in equestrian games that have their origins in historical or religious events and are currently held in many countries. This study investigated physiological stress response and health status of horses participating in the Sartiglia, a historical horse tournament held in the city of Oristano, Italy, which is principally based on the attempts of masked horsemen at a gallop to run a sword through a hole in a suspended silver star. Blood samples were collected from 21 horses the day before the tournament (D0), during the tournament (D1), and the day after the tournament (D2). Samples were analyzed for complete blood count and biochemical, hormonal, and oxidative stress assays. Data were analyzed using the mixed effect model with sampling session as one of the fixed effects. On the whole, blood parameters evidenced an optimal health status of horses at D0. Significant dehydration and increase of circulating glucose, enzymes, cortisol, and β-endorphin were registered at D1 (P < 0.001) with a complete recovery of physiological values just at D2. The reactive oxygen metabolites (d-ROM), from which the prooxidant activity can be evaluated, showed an increase from D0 to D1 and D2. Concentration of biological antioxidant potential, which measured the antioxidant capacity, was characterized by the maximum level registered during the tournament and counteracted the simultaneous increase of d-ROM. It can be hypothesized that the tournament played an important role in causing high levels of oxidant markers not only because of the physical exercise represented by the gallop but also because the emotional stressors. In conclusion, the tournament caused significant changes of most parameters, which rapidly recovered to baseline values within the day after. These data will certainly be useful for a future implementation of tests in equine medicine and for the improvements of knowledge of changes of blood parameters and health of horses in similar tournaments.

Growth hormone (GH) is encoded by theGHgene, which may be single copy or duplicate in sheep. The two copies of the sheep GH gene (GH1/GH2-NandGH2-Z) were entirely sequenced in one 106 ewes of Sarda breed, in order to highlight sequence polymorphisms and investigate possible association between genetic variants and milk traits. Milk traits included milk yield, fat, protein, casein and lactose percentage. We evidenced 75 nucleotide changes. Transcription factor binding site prediction revealed two sequences potentially recognised by the pituitary-specific transcription factorPOU1FIat theGH1/GH2-Ngene, which were lost at the promoter ofGH2-Z, which might explain the different tissues of expression ofGH1/GH2-N(pituitary) andGH2-Z(placenta). Significant differences in milk traits were observed among genotypes at polymorphic loci only for theGH2-Zgene. Sheep with homozygote genotype ss748770547 CC had higher fat percentage (P GH2-Zgene 5′ flanking region, may be a causal mutation affecting milk fat content. These findings might contribute to the knowledge of the sheepGHlocus and might be useful in selection processes in sheep.

This study was conducted, in an extensive farm, to assess the effects of artificial feeding with an acidified milk replacer on productive performance of goat kids. Thirty-two Sarda kids, randomly divided into two feeding groups of 16 kids, (NM, naturally milk fed by their dams, and AR, artificially bottle-fed with an acidified milk replacer) were weighed at weekly intervals until slaughtering, at 42 days of age. A blood sample was collected from each goat kid before slaughter for the assessment of the metabolic status. Post-mortem data were registered: carcass characteristics; percentages of commercial cuts; muscle, separable fat and bone + tendons percentage. Results were analysed by a General Linear Model procedure. The two feeding groups showed similar live weights, except for the period between 7 and 21 days of age. As regards slaughter data, AR kids had a reduced fat deposition and carcasses with shorter diameters and a longer leg. Measurements after dissection showed that the muscle/fat ratio was more favourable in AR kids. Although there were some differences between the groups, haematochemical parameters of both NM and AR were in the range reported for goat kids. On the basis of the results of this trial, artificial feeding with an acidified milk replacer can provide carcasses similar to those obtained with natural milk feeding and can be used both for goat kid meat production and eradication schemes of diseases transmitted by milk-feeding.

This study investigated the influence of casein genes polymorphism on renneting properties of milk from Sarda goats. Milk yield and composition, and renneting properties (rennet coagulation time RCT, firming time k20 and curd firmness a30) were evaluated in 200 multiparous goats from three farms, at monthly intervals from March to July. Animals were genotyped at CSN1S1 , CSN2 , CSN1S2 and CSN3 . Statistical analysis was performed by a repeated measures General Linear Model. CSN1S1 significantly affected milk traits with a lower fat content registered for goats carrying the F allele. The highest protein concentration was recorded for the CSN1S1 AB goats. Milk from CSN1S1 FF homozygote goats was characterized by a delayed k20 and the CSN1S1 AB showed a higher a30. All the parameters were influenced by the CSN2 locus, except milk yield. Polymorphism at CSN1S2 influenced only daily milk yield and a30. The CSN1S2 0 null allele was detected for the first time in this breed. The influence of genotype effect was particularly marked for CSN3 ; RCT and k20 were delayed in CSN3 BB goats and the highest level of a30, 47.88 mm registered for CSN3 AA goats, could be considered remarkable when compared to other goat breeds or populations. In conclusion, this study improved knowledge on the effects of goat casein genes on milk renneting parameters, and could be useful in the future planning of breeding programs and specific dairy products linked to the Sarda breed (PDO/PGI).

The variability of the promoter region and the 3′UTR (exon-7) of the BLG gene, encoding the β-lactoglobulin, was investigated by sequencing in 263 lactating Sarda goats in order to assess its association with milk traits. Milk traits included: milk yield, fat, total protein and lactose content, pH, daily fat and protein yield (DFPY), freezing point, milk energy, somatic cell count, total microbial mesophilic count, rennet coagulation time (RCT), curd firming rate (k20) and curd firmness (a30). A total of 7 polymorphic sites were detected and the sequence analysed was given accession number KM817769. Only three SNPs (c.−381C>T, c.−323C>T and c.*420C>A) had minor allele frequency higher than 0·05. The effects of farm, stage of lactation and the interaction farm × stage of lactation significantly influenced all the milk traits (P< 0·01,P< 0·001) except for lactose content and SCS, which were not affected by the farm, and RCT and k20, which were not affected by the stage of lactation. The BLG gene polymorphism influenced milk yield and DFPY, in relation to SNPs c.−381C>T and c.*420C>A (P< 0·01 andP< 0·05). All three SNPs affected milk pH, and this association was highly significant at c.−381C>T (P< 0·001). The c.−381TT homozygous goats showed lower pH, RCT and k20 than c.−381CT (P< 0·05). In conclusion the polymorphism of the goat BLG gene did not affect the total protein content of the Sarda goat milk, and only weakly influenced RCT and k20. On the other hand, an interesting effect on milk yields and DFPY emerged in two SNPs. This information might be useful in dairy goat breeding programs.

This study investigated the modeling of curd-firming (CF) over time (CF(t)) of sheep milk. Milk samples from 1,121 Sarda ewes from 23 flocks were analyzed for coagulation properties. Lactodynamographic analyses were conducted for up to 60 min, and 240 CF individual observations from each sample were recorded. Individual sample CFt equation parameters (RCT(eq), rennet coagulation time; CF(P), asymptotic potential value of curd firmness; k(CF), curd-firming instant rate constant; and k(SR), curd syneresis instant rate constant) were estimated, and the derived traits (CF(max), the point at which CF(t) attained its maximum level, and tmax, the time at which CF(max) was attained) were calculated. The incidence of noncoagulating milk samples was 0.4%. The iterative estimation procedure applied to the individual coagulation data showed a small number of not-converged samples (4.4%), which had late coagulation and an almost linear pattern of the ascending part of the CF(t) curve that caused a high value of CF(P), a low value of k(CF), and a high value of k(SR). Converged samples were classified on the basis of their CF(t) curves into no-k(SR) (18.0%), low-k(SR) (72.6%), and high-k(SR) (4.5%). A CF(t) that was growing continuously because of the lack of the syneresis process characterized the no-k(SR) samples. The high-k(SR) samples had a much larger CFP, a smaller k(CF), and an anticipation of tmax, whereas the low-k(SR) samples had a fast k(CF) and a slower k(SR). The part of the average CF(t) curves that showed an increase was similar among the 3 different syneretic groups, whereas the part that decreased was different because of the expulsion of whey from the curd. The traditional milk coagulation properties recorded within 30 min were not able to detect any appreciable differences among the 4 groups of coagulating samples, which could lead to a large underestimation of the maximum CF of all samples (if predicted by a30), with the exception of the no-k(SR) samples. Large individual variability was found and was likely caused by the effects of the dairy system, such as flock size (on CF(max), t(max), and % ewes with no-k(SR) milk), flock within flock size (representing 11 to 43% of total variance for % ewes with no-k(SR) milk and CF(max), respectively), days in milk (on all model parameters and CF(max)), parity (on RCT(eq), k(SR), and CF(max)), daily milk yield (on RCT(eq) and CF(max)), and position of the individual pendulum that significantly affected model parameters and derived traits. In conclusion, the results showed that the modeling of coagulation, curd-firming, and syneresis is a suitable tool to achieve a deeper interpretation of the coagulation and curd-firming processes of sheep milk and also to study curd syneresis.