Farm business and operator variables associated with bulk tank somatic cell count from dairy herds in the southeastern United States

Abstract

Mastitis is a worldwide problem in dairy cows and results in reduced milk production, the culling of cows, and other economic losses. Bulk tank somatic cell count (BTSCC) over 200,000 cells/mL often indicates underlying subclinical mastitis in dairy herds. Several preventative measures that can be implemented to help improve the incidence of mastitis exist, but surveys find these practices not fully adopted by producers. The goal of this research was to analyze the farm and operator characteristics associated with BTSCC in dairy herds by analyzing a survey of dairy producers in the southeastern United States. We examined this region because it has experienced a decline in the number of dairy farms, dairy cows, and milk production over the past 2 decades. The southeast region is also associated with higher BTSCC levels than the national average. Dairy farms in Georgia, Mississippi, Kentucky, North Carolina, South Carolina, Tennessee, and Virginia were surveyed. Producers were asked questions about the BTSCC at which they take action to address BTSCC, the information sources they use to learn about and manage BTSCC, farm structure and management characteristics, and attitudinal variables associated with profitability, managerial control, and planning horizon. Least squares regression was used to determine how these factors were associated with BTSCC levels across the 7-state region. Concern over mastitis, financial consequences of mastitis, and increased previous-year BTSCC were associated with higher current BTSCC levels. Obtaining information about mastitis from veterinarians and extension personnel, taking action against mastitis at a BTSCC less than 300,000 cells/mL, and perceived ability to control processes and mastitis incidence were associated with reduced BTSCC. We found average BTSCC was lower in North Carolina and Virginia. These results suggest that proactive producers (i.e., those that perceive they can control BTSCC and seek information from reliable sources), were more likely to report lower BTSCC. As a result, it may be possible to achieve improved milk quality, evident from lowered BTSCC, across the region.

Effect of heat stress on udder health of dairy cows

“…Regrettably, and as we have already said, numerous studies have recorded higher levels than this. There are limited time series data regarding bulk tank SCC from Asian and African countries, nevertheless, several studies have found higher values in tropical regions of these continents than in temperate regions of North America and Europe (Kelly et al, 2009;DeLong et al, 2017;Aghamohammadi et al, 2018). Suriyasathaporn et al (2012) in Thailand and Hashemzadeh and Khalajzadeh (2014) in Iran reported bulk tank SCC > 500 000 cells/ml and about 347 000 cells/ml during 2010-12 and 2006-07 respectively.…”

Dairy producers in the Southeast United States are concerned with cow care and welfare

“…This suggests a relationship between producers increased mastitis concerns and increased BTSCC. Jansen et al (2009) and DeLong et al (2017) observed that 48 and 65% of variation in BTSCC was explained by behaviors and attitudes towards mastitis and concern and control methods, respectively. However, Schewe et al (2015) reported that producers become concerned about BTSCC when counts exceed 300 000 cells/ml.…”

“…The research was supported by funding from the USDA-AFRI (Grant 2013-68004-20424), as part of a larger survey project (DeLong et al, 2017). Surveys were mailed to all grade A dairies (n = 1855) in Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee, and Virginia between 2013and 2014, as described in DeLong et al (2017.…”

Graduate Student Literature Review: Challenges and opportunities for human resource management on dairy farms

“…Some dairy extension activities are known to be valuable to farmers (Hall et al, 2019). Activities such as participatory discussion groups were associated with decreased SCC at the herd level (Dillon et al, 2016), and receiving information from an extension officer was associated with lower bulk tank SCC (Delong et al, 2017). Similarly, discussions in Danish stable schools allowed for farmers to work collectively on a problem and identify their own farm-specific goals (Vaarst et al, 2007a).…”