PubMed Health⌕ Search

Biomedical subjects

M Pauselli

Publications and source records attributed to M Pauselli.

4 recordsLinked to original sources
PubMed2004

Effect of udder health status and lactation phase on the characteristics of Sardinian ewe milk.

Mammary involution and inflammation are known to negatively affect milk quality. A trial was carried out to elucidate the mechanism by which udder health status and lactational phase determine compositional modifications in ovine milk. A total of 60 individual milk samples was collected from a group of 20 pluriparous Sardinian ewes from mid to late lactation. Each sample was assessed for its chemical characteristics, quantitative distribution of casein fractions, lactodynamographic characteristics, and enzymatic activity. Udders were classed as healthy, doubtful, or infected on the basis of repeated somatic cell counts, and samples were grouped in 3 classes of days in milk. Results indicated that both udder inflammation and mammary involution can increase plasmin (PL) activity (15.6 vs. 18.4 U/mL in healthy vs. infected udders; 14.0 vs. 20.2 U/mL in phase 1 vs. 3), which is responsible for an evident protein breakdown in milk. Significant differences between groups were observed for several characteristics. With regard to udder heath status, casein index was lower in the infected vs. healthy udders (74.8 vs. 76.6%), and beta(tot)-casein showed a similar trend (43.9 vs. 46.6%). As a consequence of protein degradation, gamma-casein (5.78 vs. 2.82%) and proteolysis index (7.60 vs. 3.82) increased in the infected group with respect to the healthy group. Udder health status also affected milk technological traits. Udder inflammation resulted in longer clotting time (20.7 vs. 16.5 min for infected vs. healthy, respectively) and in poorer curd firmness (35.6 vs. 47.6 mm for infected vs. healthy, respectively). Frequency of samples reactive to rennet was 100, 93, and 67%, respectively, for healthy, doubtful, and infected groups. With regard to lactational phase, a decrease in alpha(s1)-casein (39.13 vs. 29.36%) and beta(1)-casein (23.41 vs. 19.36%) occurred during phase 1 vs. 3, whereas kappa + alpha(s2)-casein increased (12.30 vs. 21.56%, phase 1 vs. 3). Correlation coefficients confirmed the role of PL in protein degradation. It was concluded that PL activity was strongly affected by both lactational phase and udder health status and, in turn, could be an important agent enhancing milk quality detriment.

Animals↗
PubMed1999

Effect of administration of vitamin E and selenium during the dry period on mammary health and milk cell counts in dairy ewes.

The effect of parenteral administration of two subcutaneous injections of vitamin E and Se (5 mg and 0.1 mg/kg of body weight, respectively) during the dry period on the mammary health and milk somatic cell counts of 25 dairy ewes was investigated. Supplementation reduced somatic cell counts (5.4 vs. 6.0 log10) during the subsequent lactation but had no effect on the incidence of clinical mastitis (4% vs. 6%) and intramammary infections (9.0% vs. 11.3%). Furthermore, the administration of vitamin E and Se was associated with differences in differential cell counts of milk samples (macrophages, 48.8% vs. 38.4%; polymorphonuclear neutrophils, 40.1% vs. 50.7%; and eosinophils, 0.7% vs. 1.4% for control ewes and ewes receiving supplements, respectively). The administration of these supplements also increased erythrocyte glutathione peroxidase activity (139.5 vs. 86.3 U/ml of packed cell volume) and the percentage of blood neutrophils that reduced nitroblue tetrazolium after bacterial extract stimulation (48.6% vs. 38.7%). Parenteral administration of vitamin E and Se to ewes during the dry period appeared to have influenced mammary gland status during the subsequent lactation and particularly total and differential milk cell counts.

Animals↗
PubMed1996

Total and differential cell count by direct microscopic method on ewe milk.

On 700 milk samples from single half udders of Comisana ewes, somatic cell count (SCC) and differential cell count (DCC) were determined, using a Fossomatic 90 cell counter (Foss Electric, Denmark) (SCCF) and milk smears stained with May Grünwald-Giemsa (DCCS). SCC and DCC were also determined with modified KOVAH SYSTEM (Hicor Biomedical Inc. Irvine, CA, USA) (SCCK and DCCK, respectively). Out of 665 milk samples from half udders without clinical signs of mastitis, 640 (Class I) were sterile, while 25 (Class II) were bacteriologically positive. Out of 35 milk samples (Class III) from half udders with clinical signs of mastitis, 25 were bacteriologically positive. Mean results (after logarithmic transformation of cells/ml/10(3)) of SCCF and SCCK for all the 700 milk samples were 1.89 +/- 0.58 and 1.86 +/- 0.60 with linear correlation coefficient (r) of 0.960, while least squares means for Class I, II and III were 1.78, 2.23 and 3.73 respectively and 1.75, 2.19 and 3.74 with r of 0.894, 0.979 and 0.987. Mean results of DCCS and DCCK were 38.1 +/- 23.3, 34.9, 52.1, and 82.2 PMNL% and 41.8 +/- 21.7, 38.6, 60.2, and 87.3 PMNL% with r of 0.855, 0.812, 0.697 and 0.805. The results showed high correlation coefficients and a good reliability between SCCK and SCCF and high correlation coefficients for DCC methods. In conclusion, it could be suggested that the possibility of routine use of the KOVAH SYSTEM method is particularly useful in detecting if an abnormal SCC is due to a polymorphonuclear neutrophil leukocytes increase.

Animals↗