α_S1-casein genetic variants in Sarda goat breed

Sardinia plays an important role in Italian goat breeding; this is due not only to the high extent of its patrimony and production, but also to the fact that the main breed, the Sarda goat, represents an interesting biodiversity source. As regards the morphologic variability, marked differences between subjects reared in the coast and mountain areas were found (Macciotta et al., 2002). These differences are due to the genetic selection on the autochthonous patrimony, set up by breeders and based on coat colour, horn presence and/or on functional criteria (udder shape). The need to improve milk yields also induced various breeders, mainly in those areas with better pasture conditions, to crossbreed the Sarda goats with more productive breeds. The present situation (Pazzola et al., 2002) shows how in the East coastal region (Sarrabus, Ogliastra and Baronia) and in the central mountain areas of Sardinia (Barbagia), subjects with more rural traits are reared (smaller size, small ears, presence of horns, etc.); while in the South and West areas (Sulcis and Guspinese) the influence of the Maltese breed is more evident. Both the productive traits variability (Brandano et al., 1978), and the morphologic aspect, is of great interest. Genetic variability can influence the survival of a sector hindered by the opening of the markets and by the strong competitiveness of zootechnical areas technologically more advanced. According to this point of view, considering that casein fractions are closely related to milk technological characteristics (Grosclaude et al., 1994), and to its possible productive differentiation (Remeuf, 1993), a study on αS1-casein allelic frequency was carried out, related also to the breeding region. The aim of the study is to acquire useful information in order to suggest an appropriate utilization of milk, to detect possible new alleles and to test the correlation between casein phenotype and morphology of the animals

Effect of dietary vitamin E content on the CLA, cholesterol and triglycerides composition of Italian Mediterranean buffalo meat

The composition of fatty acids, CLA, triglycerides and cholesterol in intramuscular fat depots of buffalo meat was determined using high-resolution gas chromatography to investigate the influence of dietary vitamin E content. Three groups of Italian Mediterranean buffalo calves were fed on three diets with high (H), low (L) and zero (Z) vitamin E contents. The animal were slaughtered at 15 months and three muscles were dissected on the half-carcass: Longissimus dorsi (LD), Tricipitis brachii (TB) and Semimembranosus (Sm). Lipid extracts from muscles (g/100g f.m.: 0.82 for LD, 0.66 for TB and 0.48 for Sm) were used to quantify the amount (mg/100g of lipids) of fatty acids, total conjugated linoleic acid (CLA) and cholesterol. The effects of dietary vitamin E content were significant (P<0.05) but marginal. Comparison of lipid extracts from muscles showed that C18:2 and total CLA were higher respectively in TB and Sm muscles when vitamin content was low. Also Cholesterol content variation was affected by low dietary vitamin E: LD muscle has a lower cholesterol concentration for diet L. The different vitamin content of two diets did not significantly influence the composition of triglycerides. Considering the low lipid concentrations (<1g/100 g of fresh muscle) none of the meat muscles should be considered a significant source of CLA

Short communication: Molecular genetic characterization of ovine αS1-casein allele H caused by alternative splicing

Abstract Sequencing of ovine CSN1S1*H cDNA showed an absence of exon 8 in comparison with GenBank sequences; the absence was confirmed by protein sequencing. We demonstrated that this allelic aberration is the result of a deletion of 4 nucleotides, the last 3 of exon 8 and the first 1 of intron 8, which are replaced by an insertion of 13 nucleotides in the DNA sequence. The insertion is a precise duplication of a part of the adjacent intronic sequence of CSN1S1*C″ . These sequence differences result in an inactivation of the splice donor sequence distal to exon 8, leading to upstream exon skipping during the serial splice reactions of the ovine CSN1S1*H pre-mRNA, and may affect the specific casein expression as well as protein characteristics

Sensory profile of P.D.O. Mozzarella di Bufala Campana Cheese

The aim of this work was to define the typical sensory profile of DOP Mozzarella di Bufala Campana cheese as related to the technological process (industrial or artisanal), the geographical area (Salerno or Caserta), the season (spring or summer) and to the chemical composition of both milk and cheese. The results obtained showed that the sensorial profile of Mozzarella DOP changed for each variable considered. In particular, Caserta samples were more salty, with a more intense butter odour, higher peelability and homogeneity surface than those from Salerno area; the industrial samples, compared to the artisanal ones, were more salty, hard and "chewable", and exhibited an external layer more difficult to remove and more homogeneous

Occurrence of quantitative genetic polymorphism at the caprine beta-CN locus, as determined by a proteomic approach

Genetic screening of caseins in caprine milk samples enabled the identification of two novel b-casein (b- CN) phenotypes, C2 and F1, expressed at lower levels (3.3 and 2.7 g L_1 per allele, respectively) than reference b-CN C (4.7 g L_1 per allele), and another lacking in aS-complex. The b-CN C2 and F1 primary structures, determined by MS analysis, corresponded to b-CN C and F, respectively. The reasonable hypothesis supporting the low expression of both variants considers the C2 and F1 alleles as deriving from b-CN C1 and b-CN A1 precursors, respectively, and characterised by a genic transition C/T negatively affecting the mRNA stability. Further, phosphorylation of Thr41 responsible for the 7P b-CN component was determined by a proteomic approach for the first time. Caprine milk containing low levels of antigenic aS1-, aS2- and b-CN can be used for infant formula production and drinking milk for people with cows' milk protein allergy