Effects of clinical mastitis caused by gram-positive and gram-negative bacteria and other organisms on the probability of conception in New York State Holstein dairy cows

Abstract

The objective of this study was to estimate the effects of different types of clinical mastitis (CM) on the probability of conception in New York State Holstein cows. Data were available on 55,372 artificial inseminations (AI) in 23,695 lactations from 14,148 cows in 7 herds. We used generalized linear mixed models to model whether or not a cow conceived after a particular AI. Independent variables included AI number (first, second, third, fourth), parity, season when AI occurred, farm, type of CM (due to gram-positive bacteria, gram-negative bacteria, or other organisms) in the 6 wk before and after an AI, and occurrence of other diseases. Older cows were less likely to conceive. Inseminations occurring in the summer were least likely to be successful. Retained placenta decreased the probability of conception. Conception was also less likely with each successive AI. The probability of conception associated with the first AI was 0.29. The probability of conception decreased to 0.26, 0.25, and 0.24 for the second, third, and fourth AI, respectively. Clinical mastitis occurring any time between 14 d before until 35 d after an AI was associated with a lower probability of conception; the greatest effect was an 80% reduction associated with gram-negative CM occurring in the week after AI. In general, CM due to gram-negative bacteria had a more detrimental effect on probability of conception than did CM caused by gram-positive bacteria or other organisms. Furthermore, CM had more effect on probability of conception immediately around the time of AI. Additional information about CM (i.e., its timing with respect to AI, and whether the causative agent is gram-positive or gram-negative bacteria, or other organisms) is valuable to dairy personnel in determining why some cows are unable to conceive in a timely manner. These findings are also beneficial for the management of mastitic cows (especially those with gram-negative CM) when mastitis occurs close to AI.

Factors affecting reproductive performance of dairy cow in Algeria: Effects of clinical mastitis

“…These findings were in accordance with that of previous studies (Gunay and Gunay, 2008;Ahmadzadeh et al, 2009;Hertl et al, 2010;Nava-Trujillo et al, 2010;Yang et al, 2012). Although the correlation of mastitis with high infertility rates is well known, the mechanisms underlying this relationship are not clear and several hypotheses could be formulated.…”

Lipopolysaccharide Reduces the Primordial Follicle Pool in the Bovine Ovarian Cortex Ex Vivo and in the Murine Ovary In Vivo1

“…Metritis and mastitis perturbation result in several aspects of ovarian function, including retarded follicular growth, reduced circulating and intrafollicular estradiol concentrations, altered duration of luteal phases, and disruption of ovarian cyclic activity [3][4][5][6]. However, infections of the uterus and mammary gland not only cause infertility at the time of infection but reduced fecundity also persists even after resolution of disease [1,7]. An intriguing question about biological mechanisms is how these Gram-negative bacterial infections in tissues distant from the ovary can impact ovarian function?…”

Progression to multi-scale models and the application to food system intervention strategies

“…These herds are relatively large well-managed dairy farms using freestall housing, total mixed ration feeding and parlor milking. Using these data we have generated parameter estimates for our dynamic program model at 3 levels (generic (i.e., pathogen-unidentified), Gram±, and bacteria specific): risk of mastitis (Bar, 2007;Schukken et al, 2010), mortality (Gröhn et al, 2005;Bar et al, 2008a;Hertl et al, 2011;Cha et al, 2013), conception (Wilson et al, 2008;Hertl et al, 2010Hertl et al, , 2014a, milk loss Bar et al, 2007;Schukken et al, 2009;Hertl et al, 2014b), and associated costs (treatment, culture, and discarded milk).…”