Threshold somatic cell count for delineation of subclinical mastitis cases

Abstract

Aim:Somatic cell count (SCC) is the most widely used single reliable indicator of udder health. The present study was carried out with an objective to find the exact threshold of SCC.Materials and Methods:Milk samples collected from a total of 214 Holstein Friesian crossbred dairy animals were subjected to bacterial DNA extraction and SCC estimation by digital PortaCheck. California Mastitis Test and polymerase chain reaction based on amplification of organism using reported primers were performed to diagnose subclinical mastitis. Receiver’s operating characteristic (ROC) curve analysis and discriminate function analyses were performed using SPSS 18 software.Results:ROC curve analysis represented that the area under the curve was 0.930 with the standard error of 0.02. Results indicated that 93% of the case could be correctly predicted as mastitis infected using SCC as a marker (p<0.001). At cut score level of 282 000 cells/ml, 285,000 cells/ml and 288,000 cells/ml, sensitivity remained 92.6% and specificity augmented as 86.3%, 87.2%, and 88%, respectively. At SCC value of 310,000 cells/ml of milk, sensitivity and specificity were optimal, namely, 92.6% and 91.5%, respectively. The function fitted demonstrated 89.2% accuracy with p<0.001. The functions at group centroids were −0.982 and 1.209, respectively, for normal and mastitis-infected animals and log_SCC value was the most important factor contributing 38.30% of the total distance measured.Conclusion:Our study supports that the threshold value to delineate subclinical mastitis case from the normal is 310,000 somatic cells/ml of milk and a model so fitted using the variable SCC can be successfully used in field for the diagnosis of subclinical cases of mastitis which otherwise would be difficult to differentiate based on clinical signs.

Three Novel Players: PTK2B, SYK, and TNFRSF21 Were Identified to Be Involved in the Regulation of Bovine Mastitis Susceptibility via GWAS and Post-transcriptional Analysis

“…Chinese Holstein cows used for 2b-RADseq library and independent sample population validation came from two different pastures of the Nanjing Weigang Dairy Co., Ltd. At 2b-RADseq stage, forty dairy cows, daughters of ten bulls, were selected from 596 lactating Chinese Holstein in the third early-lactation period (15–60 d), which were further divided into two subgroups according to their clinical mastitis phenotypes [mammary gland (visual observation): red, swollen, fever, pain, and milk flocculation, etc., and laboratory diagnosis (mainly SCC)] (46, 47): case group [20 cows, clinical mastitis appeared in all three lactation periods, and SCC values [(2100.3 ± 891.1) × 10 4 ) > 100 × 10 4 cells/ml] and control group [20 cows, no mastitis during the three lactation periods, and SCC values [(22.4 ± 6.8) × 10 4 ) < 30 × 10 4 cells/ml]. At the independent sample population validation stage, 383 cows (73 in case group and 310 in control group), daughters of thirty-one bulls, were selected from 886 lactating cows in the third early-lactation period (15–60 d) in another pasture for population genetics verification.…”

Technological interventions and advances in the diagnosis of intramammary infections in animals with emphasis on bovine population—a review

“…Jadhav et al. (2018) have delineated subclinical mastitis from normal udder on the basis of SCC; Holstein Friesian cows were tested for SCC estimation by digital PortaCheck. CMT and PCR were used to diagnose subclinical mastitis.…”

“…2015), lactose (Pyörälä 2003), somatic cell count (SCC) (Jadhav et al. 2018), microbial load (Vakkamäki et al. 2017; Mishra et al.…”

Effect of a natural plant ingredient — Pulsatilla saponin B4 on clinical mastitis and serum inflammatory indices in dairy cows

“…Mastitis in dairy cows is caused mainly by the in ammatory reaction induced by toxic products secreted by infecting bacteria [1]. With the incidence of clinical mastitis, the permeability of the mammary vein is increased, which in turn enhances the chemotaxis of leukocytes and elevates the somatic cell counts in the milk [2]. Meanwhile, in ammatory agents (exempli gratia endotoxin) will lead to the synthesis and secretion of in ammatory factors (including leukotrienes B4 (LTB4), prostaglandin E2 (PGE2), interleukin-1 alpha (IL-1α), interleukin-1 beta (IL-1β), interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumour necrosis factor alpha (TNF-α) [3,4] and induce hepatic secretion of C-reactive protein (CRP), serum amyloid A protein (SAA), and haptoglobin (HP) [5].…”