Twenty lactating Girgentana goats were used to evaluate the effect of morning v. afternoon cutting time of Berseem clover (Trifolium alexandrinum L.) on feed intake, milk yield and milk composition. Goats were randomly divided into two groups of ten animals, receiving 10 kg of fresh Berseem clover cut at 9.00 (AM group) or 16.00 (PM group), respectively; 500 g of concentrate was given individually to goats before offering forage. Feed intake increased (P<0·01) in the PM group (30·5 v. 25·3 g dry matter/kg body weight), associated with the different nutrient content of diets: lower crude protein but higher dry matter, neutral detergent fibre, water soluble carbohydrates (WSC) and total fatty acids in the PM-harvested forage. Milk production, protein and casein content were higher (P<0·05) in the PM group (1415 g/d, 3·25% and 2·42% v. 1277 g/d, 3·15% and 2·33%, respectively), whereas no differences between groups were detected for milk fat, lactose or urea content. Body weight slowly decreased from the start to the end of the experiment, without differences between groups. This study showed an important milk yield responses in Girgentana goats offered afternoon-cut compared with morning-cut Berseem clover, due to a marked increase in WSC in the afternoon-cut forage.

Nutritional value is a priority in new product development. Using vegetable or marine oils, rich in polyunsaturated fatty acids, in dairy beverage formulations is an option to provide the consumers with healthier products. However, these formulations are prone to oxidation, which is responsible for rapid flavour degradation and the development of potentially toxic reaction products during storage. Flaxseed lignans, secoisolariciresinol diglucoside (SDG), and its mammalian metabolites have antioxidant activity and could be used in beverage formulations to prevent oxidation. Commercially available SDG extract was added to the formulation of dairy beverages enriched with flaxseed oil. As an alternative approach, dairy beverages were produced from milk naturally rich in SDG metabolites obtained through the alteration of cow diet. Resistance to oxidation was determined from the kinetics of hexanal and propanal production during heat and light exposure treatments. Increasing SDG concentration in dairy beverage slightly reduced redox potential but had no effect on oxygen consumption during oxidation treatments. The presence of SDG in dairy beverage significantly improved resistance to heat- and light-induced oxidation. However, purified enterolactone, a mammalian metabolite from SDG, prevented oxidation at much lower concentrations. The use of milk from dairy cow fed flaxseed meal did not improve resistance to oxidation in dairy beverage. Enterolactone concentration in milk was increased by the experimental diet but it remained too low to observe any significant effect on dairy beverage oxidation.

In this work, a method based on Raman spectroscopy in combination with Principal Component Analysis (PCA) and Partial Least Square-Discriminant Analysis (PLS-DA) has been developed for the rapid differentiation of heterofermentative related lactobacilli. In a first approach, Lactobacillus kefir strains were discriminated from other species of heterofermentative lactobacilli: Lb. parakefir and Lb. brevis. After this first approach, PCA allowed for a clear differentiation between Lb. parakefir and Lb.brevis. For the first level of discrimination, PCA was performed on the whole spectra and also on delimited regions, defined taking into consideration the loading values. The best regions allowing a clear differentiation between Lb. kefir and non-Lb. kefir strains were found to be: the 1700–1500 cm−1, 1500–1185 cm−1 and 1800–400 (whole spectrum) cm−1 Raman ranges. In order to develop a classification rule, PLS-DA was carried out on the mentioned regions. This method permitted the discrimination and classification of the strains under study in two groups: Lb. kefir and non-Lb. kefir. The model was further validated using lactobacilli strains from different culture collections or strains isolated from kefir grains previously identified using molecular methods. The second approach based on PCA was also performed on the whole spectra and on delimited regions, being the regions 1700–1500 cm−1, 1500–1185 cm−1 and 1185–1020 cm−1, i.e., those allowing the clearest discrimination between Lb. parakefir and Lb. brevis. The results obtained in this work, allowed a clear discrimination within heterofermentative lactobacilli strains, proteins being the biological structures most determinant for this discrimination.

Staphylococcus aureus is one of the most important infectious mastitis causative agents in small ruminants. In order to know the distribution of Staph. aureus strains associated with infectious mastitis in flocks of sheep in the northeast of Brazil and establish whether these clones are related to the strains distributed internationally, this study analysed the genetic diversity of Staph. aureus isolates from cases of clinical and subclinical mastitis in ewes by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). In this research, 135 ewes with mastitis from 31 sheep flocks distributed in 15 districts were examined. Staph. aureus was isolated from sheep milk in 9 (29%) out of 31 herds located in 47% of the districts surveyed. MLST analysis allowed the identification of four STs (ST750, ST1728, ST1729 and ST1730). The last three with their respective novel alleles (glp-220; pta-182 and yqil-180) were recently reported in the Staph. aureus MLST database (http://www.mlst.net). Each novel allele showed only a nucleotide different from those already described. The occurrence of CC133 (ST750 and ST1729) in this study is in agreement with other reports that only a few clones of Staph. aureus seem to be responsible for most cases of mastitis in dairy farms and that some of these clones may have broad geographic distribution. However, the prevalence of CC5 (ST1728 and ST1730)—an important group related to cases of colonization or infection in humans—differs from previous studies by its widespread occurrence and may suggest human contamination followed by selective pressures of the allelic diversifications presented for these STs.

CD4+ T cells play a key role in the immune response of pathogen-induced mastitis in dairy cattle. Mammary gland factor STAT5b is involved in the regulation of CD4+T cell differentiation during inflammatory response and milk production. Little is known about the genetic variation effects of bovine CD4 and STAT5b genes on somatic cell score (SCS) and milk production traits in dairy cattle. The aim of the study was to investigate the single nucleotide polymorphisms (SNPs) of bovine CD4 and STAT5b in Chinese Holsteins and to analyse their association with estimated breeding values (EBVs) for SCS and milk production traits. In the present study, SNPs of CD4 (NC_007303 g.13598C>T) and STAT5b (NC_007317 g.31562 T>C) were identified and genotyped in Chinese Holstein population. The results showed that both SNPs were significantly associated with the EBVs for milk yield and protein yield in Chinese Holstein cows, and the SNP in CD4 was associated with the EBV for SCS (P<0·01). The additive effect of CD4 SNP on protein yield was significant (P<0·05), and the dominant effect of STAT5b SNP was significant on milk yield and protein yield (P<0·01). Cows with combination genotype C7 (CCTT: CD4 g.13598C>T and STAT5b g.31562 T>C) had the highest SCS EBV but lower milk yield, while cows with C2 (TTTC) produced more milk, fat and protein than the other eight combination genotypes. These results suggested that the SNPs in CD4 and STAT5b may be potential genetic markers for SCS and milk/protein yields selecting and warrant further functional research.

A large dataset comprising output from an automatic milking (AM) system between 1999 and 2006 was examined and a total of 172 cow lactation curves and 68 heifer lactation curves were identified for further analysis. Relationships between milking frequency at different stages of lactation and lactation persistency and total lactation yield were determined. Cows had higher peak and total milk yields than heifers, but heifers had higher persistency (defined as the rate of decline in milk yield between days 100 and 300 post calving). Milking frequency did not differ significantly between cows and heifers in early lactation, but thereafter decreased significantly more in cows than in heifers. The effect of milking frequency on yield characteristics was analysed by comparing the highest and lowest quartiles for milking frequency. High milking frequency in early lactation was consistently associated with increased peak yield. High milking frequency averaged across the whole lactation was associated with increased peak yield in both cows and heifers, and with improved lactation persistency in cows only. This resulted in total lactation yield that was 21% greater in the high quartile cows compared with the low.

Subclinical mastitis (SM) is a major concern in the dairy industry because it causes economic losses and can lead to clinical mastitis. The mechanisms of the onset and progression of SM are not fully understood, and a new procedure for the detection and appropriate prediction of SM leading to clinical mastitis is necessary for dairy cow management. Inflammatory cytokines such as interleukin (IL)-6 are known to be present in inflamed mammary glands at the onset of mastitis, and IL-6 concentrations correlate with the levels of inflammation. In this study, the detection of IL-6 was examined for the evaluation for the future prediction of SM in 77 quarter milk samples from 20 cows. IL-6 concentrations in quarter milk were measured by sandwich ELISA, and the data were compared with milk somatic cell count (SCC) levels to diagnose SM. Average IL-6 concentration was significantly higher in SM quarter milk (207·0±441·6 pg/ml) than in healthy control quarter milk (12·6±33·4 pg/ml, P<0·01). Results of the cross-tabulation table show that SM prediction accuracy based on IL-6 concentration was almost equal or superior to SM prediction accuracy based on SCC. The detection of IL-6 in milk indicated SM earlier than did the detection of elevated SCC. Thus, the detection of IL-6 in milk could be a future prediction marker for SM.

Dry matter, protein, fat, pH, mineral (Na, K, Ca and Mg) and trace elements (Fe, Cu, Zn and Se) concentrations were determined in samples of goats’ milk and in fresh, semi-hard and hard cheeses to study the effect of the goats’ diet and the type of rennet used for the cheese processing of the Palmero Protected Designation of Origin cheeses. Two groups of 20 Palmero goats were fed 2 different diets: a Palmero diet (PD supplied by native forages adapted to subhumid areas, which had a high ratio of long fibre to concentrates (65:35), and an actual diet (AD), the most commonly used by goat farmers, with a low ratio of long fibre to concentrates (35:65). In general, the cheese samples from goats fed with PD had higher mean Ca, Zn, Cu and Se concentrations than the samples obtained from AD fed goats. The diet exhibited a greater influence on the chemical composition of the cheeses than the rennet used in their production. Applying a stepwise linear discriminant analysis a complete percentage of correct classifications of the three types of cheeses according to the diet of the goats was observed.

Massese is an Italian sheep breed, with black or grey coat colour, mainly reared in the Tuscany and Emilia Romagna regions. Recently, the emerging interests in this breed have resulted in the production of Pecorino cheese obtained with only Massese milk. In order to be profitable, this marketing link between Massese breed and its products should be defended against fraudsters who could include milk of other sheep breeds or cow milk in Massese labelled productions. To identify the genetic factors affecting coat colour in sheep, we have recently analysed the melanocortin 1 receptor (MC1R) gene and identified several single nucleotide polymorphisms (SNPs). In this work, as a first step to set up a DNA based protocol for authentication of Massese dairy products, we further investigated the presence and distribution of one of these SNPs (c.-31G>A) in 143 Massese sheep and in another 13 sheep breeds (for a total of 351 animals). The Massese breed was fixed for allele c.-31A, whereas in all other breeds allele c.-31 G was the most frequent or with frequency of 0·50. At the same nucleotide position the cattle MC1R gene carries the G nucleotide. Using these data we developed a method to detect adulterating milk (from other sheep breeds or from cow) in Massese dairy products based on the analysis of the c.-31G>A SNP. We first tested the sensitivity of the protocol and then applied it to analyse DNA extracted from ricotta and Pecorino cheese obtained with only Massese milk or obtained with unrestricted sheep and cattle milk. To our knowledge, this system represents the first one that can be used for breed authentication of a sheep production and that, at the same time, can reveal frauds derived from the admixture of milk of an unreported species.