Dynamics of somatic cell count and intramammary infection in lactating dairy cows.

S Sumon,Md Ehsan,Md Islam,Mst Parvin

doi:10.5455/javar.2020.g423

S Sumon, Md Ehsan + Show 2 more

Open Access

https://doi.org/10.5455/javar.2020.g423

Copy DOI

Abstract

Objective:The influence of intramammary infection (IMI) and types of bacteria was assessed on somatic cell count (SCC) in dairy cows’ milk with respect to breed, age, parity, stage of lactation, milk production, and mammary quarter location.Materials and methods:After recording data in a structured questionnaire, 360 samples of quarter milk were collected. The samples were subjected to SCC and isolation and identification of bacteria. The data were analyzed to find out the significant influence of independent factors on SCC and IMI.Results:The infected quarters had a significantly higher mean SCC (210.52 × 103 cells/ml) compared to uninfected ones (32.72 × 103 cells/ml). The mean SCC was the highest for IMI with Enterobacter spp. (338.00 × 103 cells/ml) followed by Bacillus spp. (319.20 × 103 cells/ml), coagulase-negative Staphylococci (CNS) (268.17 × 103 cells/ml), Staphylococcus aureus (218.31 × 103 cells/ml), and Escherichia coli (200.75 × 103 cells/ml) and the lowest for Pseudomonas aeruginosa (66.33 × 103 cells/ml). Milk of rear quarters had a significantly higher SCC than the front quarters. SCC increased with increasing age, parity, and lactation stage regardless of whether cows are infected or not. The IMI was more prevalent in rear quarters (42.2%) and cows at early (≤7 days) lactation (100.0%). Cows having a parity of ≥5 and crossbred and high yielding (>5 l) cows had also a higher rate of IMI of 38.2%, 36.7%, and 38.2%, respectively.Conclusion:The IMI and type of bacteria were the principal factors for SCC variation. Besides, mammary quarter location, age, and parity should be taken into consideration during the interpretation of SCC.

Highlights

Somatic cell count (SCC) in individual cow’s milk or bulk milk is routinely used to assess the status of subclinical mastitis (SCM) in dairy cow herds and recognized as the standard test for the quality of milk, worldwide
The major pathogens typically cause a high increase in somatic cell count (SCC), and an infection with minor pathogens normally leads to a slight increase in SCC and rarely to clinical mastitis [2,9]
The difference in SCC caused by various mastitic pathogens in this study may be due to the variation in cow’s disposition of protective mechanism and the process of establishment of infection by the pathogen [15]

Summary

Introduction

Somatic cell count (SCC) in individual cow’s milk or bulk milk is routinely used to assess the status of subclinical mastitis (SCM) in dairy cow herds and recognized as the standard test for the quality of milk, worldwide. Despite a greater variation in SCC in dairy cows, scarce information is available on factors that may influence SCC in dairy cows submitted to a tropical environment such as Bangladesh, where the cows are mainly kept semi-intensive, as compared to the currently available data for cows maintained on temperate conditions. In light of these facts, the objective of this research was to identify the impact of IMI, types of bacterial species, and factors other than IMI on SCC in lactating cows

Study design and sampling

Results and Discussion

Conclusions

Conflict of interest