Investigating the relationship between raw milk bacterial composition, as described by intergenic transcribed spacer-PCR fingerprinting, and pasture altitude.

AIMS: To assess the bacterial biodiversity level in bovine raw milk used to produce Fontina, a Protected Designation of Origin cheese manufactured at high-altitude pastures and in valleys of Valle d'Aosta region (North-western Italian Alps) without any starters. To study the relation between microbial composition and pasture altitude, in order to distinguish high-altitude milk against valley and lowland milk. METHODS AND RESULTS: The microflora from milks sampled at different alpine pasture, valley and lowland farms were fingerprinted by PCR of the 16S-23S intergenic transcribed spacers (ITS-PCR). The resulting band patterns were analysed by generalized multivariate statistical techniques to handle discrete (band presence-absence) and continuous (altitude) information. The fingerprints featured numerous bands and marked variability indicating complex, differentiated bacterial communities. Alpine pasture milks were distinguished from lowland ones by cluster analysis, while this technique less clearly discriminated alpine pasture and valley samples. Generalized principal component analysis and clustering-after-ordination enabled a more effective distinction of alpine pasture, valley and lowland samples. CONCLUSIONS: Alpine raw milks for Fontina production contain highly diverse bacterial communities, the composition of which is related to the altitude of the pasture where milk was produced. SIGNIFICANCE AND IMPACT OF THE STUDY: This research may provide analytical support to the important issue represented by the authentication of the geographical origin of alpine milk productions.

Genetic traceability of the geographical origin of typical Italian water buffalo Mozzarella cheese: a preliminary approach.

AIMS: To distinguish Italian Protected Designation of Origin (PDO) water buffalo Mozzarella from different producers on a molecular basis in relation to the place of manufacturing within the production district, and to develop a tool for genetic traceability of typical dairy products. METHODS AND RESULTS: Microbial DNA was isolated from Mozzarella's governing liquid to amplify the whole microflora's ribosomal 16S-23S internal transcribed spacers (ITS)-PCR fingerprinting by means of an original primer pair. Phylogenetic distance analyses were performed on the obtained electrophoretic band patterns by maximum parsimony and neighbour-joining tree construction algorithms for discrete binary data, using a conventional bootstrap resampling test. The observed band profiles showed high repeatability and specificity, allowing unambiguous distinction of each sample; phylogenetic analyses yielded the same tree topology with good strength of nodal support. Moreover, a relationship between the genetic distances among samples and the actual geographical ones separating the respective producing dairies was observed. CONCLUSIONS: The genetic diversity of PDO water buffalo Mozzarella's microflora, observed by ITS-PCR fingerprinting, can be exploited to discriminate cheeses from differently located dairies. SIGNIFICANCE AND IMPACT OF THE STUDY: Given the increasing importance of food traceability for safety, quality and typicalness issues, the ITS-PCR fingerprinting protocol described here may represent a suitable tool for tracing the geographical origin of Italian Mozzarella.

Onset and sequence of RBA-band replication on the inactive X-chromosomes of cattle (Bos taurus L.), river buffalo (Bubalus bubalis L.) and goat (Capra hircus L.).

This study was undertaken to provide cytogenetic information about onset and sequence of RBA-band replication on the inactive X-chromosomes of cattle, river buffalo and goat. Blood cultures were synchronized overnight with thymidine after 48 hours of growth. The cell block was released with fresh medium and the cells allowed to grow in the presence of BrdU and H33258 for 1, 2, 4, 6, 8, 10, 12 and 14 hours, including 20 minutes colcemide. Results show that: (a) the onset of RBA-banding replication was 12 hours before mitosis in cattle and river buffalo, 14 hours in the goat; (b) the replication process was still 'on' in cattle and river buffalo one hour before mitosis, whereas it was 'off' in the goat; consequently the length of the G2 phase was less than one hour in cattle and river buffalo and one hour or slightly longer in the goat; (c) the first band undergoing replication was identified as band Xq31 in cattle, homologous to band Xq34-36 in river buffalo and Xq24 in the goat; (d) the second replicating band was the Xp22 in cattle, homologous to band Xq21 in river buffalo and Xq34 in the goat, respectively; (e) the sequence of RBA-band replication was quite similar between cattle and river buffalo, but reversed in the goat, due to the wide chromosomal rearrangements which differentiated the X-chromosome of Caprinae from that of Bovinae.

Plasma levels of luteinizing hormone, estradiol and androstenedione in sows with inadequate plasma progesterone.

The authors report the profiles of luteinizing hormone (LH), estradiol (E2), progesterone (P) and androstenedione (A) in some female pigs with altered plasma hormonal levels. Twenty cycles are described and 19 out of them are characterized by low plasma P in luteal phase of different etiology, at least as measured by hormone concentrations. The following disorders are observed: a) possible impairment of follicular maturation; b) impaired LH secretion in presence of too high E2; c) low LH base-line values; d) inadequate luteal phase; e) short luteal phase; f) heat disorders. An attempt is made to correlate the altered hormonal profiles with the high rate of summer conception failure in sows.

Endocrine profiles of sows during the oestrous cycle.

We measured the plasma concentrations of luteinizing hormone (LH), oestradiol (E2), progesterone (P), 17 alpha-hydroxy progesterone (17P), androstenediona (A) and testosterone (T) at oestrus and during the oestrous cycle for four consecutive cycles in a group of 15 normal sows. The results show that at oestrus the peak LH value was preceded, 24 hours earlier, by an E2 peak, and indicate that the LH rise begins when E2 concentrations reach their highest value. During diestrus, concentrations of LH and E2 were constantly low, P and 17P were characterized by lowest concentrations during the oestrous period which showed significant (p less than 0.001), progressive increases from the second day after the LH ovulatory peak, to reach their highest values after 8-14 days. The 17P decrease in proestrus precedes that of P.T and A concentrations showed a significant (p less than 0.001) increase 2 days before the LH ovulatory peak; high plasma concentrations of both androgens were maintained until the LH peak occurred. Measurements taken in consecutive cycles in the same animals showed a high reproducibility of the hormone concentrations examined, which showed similar patterns and values in each of the cycles studied. This high reproducibility suggests that these hormones have an important physiological role and may affect oestrous behaviour.