Effects of Mastitis on Buffalo Milk Quality

Abstract

The objectives of this study were to compare the effectiveness of different indicators of mammary inflammation in buffalo and to evaluate the association of the indicators with buffalo milk yield, composition, and rennet coagulation properties. This study was carried out at four buffalo farms in central Italy using a total of 50 lactating buffalo. Milk from each buffalo was tested at the beginning, middle, and end of lactation. To evaluate the relationship between mastitis markers and milk components, three classes were defined for each of the following markers: total somatic cell count (TSCC), differential somatic cell count (DSCC), and bacteriological results The regression coefficient for the reference method and the alternative method of determining TSCC was 0.81, indicating that the method routinely used to analyze buffalo milk consistently underestimated actual TSCC. The milk samples positive for udder-specific bacteria also had higher TSCC values than the samples that were negative for bacteria (872×10 3 /ml vs. 191×10 3 /ml). In samples that were positive for udder-specific bacteria, polymorphonuclear leukocytes (PMN) made up greater than 50% of the cells. Moreover, only 1% of the samples in the lowest TSCC class were positive for bacteria. The correlation between TSCC and PMN was stronger (0.70), and PMN values in buffalo milk increased significantly when the TSCC class changed from low (38%) to medium and high (56% and 64%). Milk yield was negatively related to TSCC. Significant changes in lactose (4.87%, 4.80% and 4.64%) and chloride content (0.650 mg/ml, 0.862 mg/ml and 0.882 mg/ml) were also observed with increasing TSCC values. Higher TSCC was associated with impaired rennet coagulation properties: the clotting time increased, while the curd firming time (p≤0.05) and firmness decreased. We concluded that in buffalo as in dairy cows, TSCC is a valid indicator of udder inflammation; we also confirmed that a value of 200×10 3 cells/ml should be used as the threshold value for early identification of an animal affected by subclinical mastitis. In addition to its association with significantly decreased milk yield, a TSCC value above this threshold value was associated with changes in milk composition and coagulating properties.

Receiver operating characteristic analysis of milk lactosefor identification of mastitis in buffaloes

“…The milk lactose per cent remained significantly higher in normal quarters and decreased significantly by 7.79% and by 9.73% during moderate and severe infection, respectively (P<0.05). Lower milk lactose observed during mastitis is in agreement with previous studies in dairy buffaloes (Bansal et al, 2007;Sharif Tripaldi et al, 2010;Hussain et al, 2012). Lower lactose content may be due to impairment of synthetic activity of mammary tissues or decomposition by leucocytes or mastitis causing pathogens or leakage from milk into blood (Hussain et al, 2012;Reis et al, 2013).…”

“…Lower lactose content may be due to impairment of synthetic activity of mammary tissues or decomposition by leucocytes or mastitis causing pathogens or leakage from milk into blood (Hussain et al, 2012;Reis et al, 2013). Hence, lactose could be used as an indicator due to consistent change during intramammary infections (Tripaldi et al, 2010;Reis et al, 2013).…”

“…Further, fat is considered as the most variable milk component, followed by protein and lactose is the least variable (Ravikala et al, 2014). On the other hand, during mastitis, alteration of milk lactose occurs markedly compared to other traits (Bansal et al, 2007;Sharif et al, 2007;Tripaldi et al, 2010;Hussain et al, 2012;Reis et al, 2013). Hortet and Seegers (1998) reviewed the alteration of milk fat and protein during mastitis and observed that the alterations were contradictory to several authors.…”

“…Therefore, milk lactose content could be used as mastitis indicator in dairy animals. Though, few studies reported threshold values of milk lactose for mastitis identification in cows (Pyorala, 2003;Bansal et al, 2005;Tripaldi et al, 2010) and buffaloes (Bansal et al, 2007), the threshold values for identification of mastitis in Jaffrabadi buffalo is not available. Hence, the present study aimed to see the overall accuracy of milk lactose to classify mastitis and normal condition and to find a suitable optimum threshold value of milk lactose for mastitis identification along with Se, Sp and LR+ in Jaffrabadi buffaloes using ROC analysis.…”

Buffalo milk composition, processing factors, whey constituents recovery and yield in manufacturing Mozzarella cheese

“…Tripaldi et al (2010) found an average of 80.44% for casein/protein ratio in buffalo milk; Costa et al (2014) identified an average of 79.17% (min. of 78.07 and max.…”