The effect of failed transfer of passive immunity and agammaglobulinemia on the occurrence of preweaning diarrhea, pneumonia, and mortality in Holstein calves

Aim of study: To evaluate the effect of failed transfer of passive immunity (FPI; Brix% < 8, equivalent to serumimmunoglobulin G <10.1 g/L) and agammaglobulinemia (AG; Brix% ≤ 6.5, equal to 0 g/L serum immunoglobulin G) assessed with a digital Brix refractometer on the occurrence of pre-weaning diarrhea, pneumonia and mortality in Holstein female calves. Area of Study: Hot-arid zone of northern Mexico (25 °N). Material and methods: Health events and mortality records were obtained from Holstein calves (n = 4,349) in a large commercial dairy herd. Multiple logistic regression analyses were used to model the effect of the failure of passive transfer of maternal immunoglobulins or AG on preweaning diarrhea, pneumonia, and mortality of Holstein calves. Main results: Calves with FPI 24 h post-calving had 1.9 greater odds of presenting preweaning diarrhea than herdmates not having FPI. Agammaglobulinemic calves were 2.6 times more likely to suffer preweaning diarrhea than calves not having this condition. Calves with FPI had 1.4 greater odds of having preweaning pneumonia than calves not presenting FPI. Calves with AG were 2.1 times more likely to get pneumonia than those with no AG. Episodes of diarrhea predisposed calves to pneumonia (odds ratio= 3.8). The odds of dying before 60 days of age were 1.9 times higher in calves with FPI. Research highlights: These results reaffirm that FPI and AG 24 h post-calving increase the risk of preweaning diarrhea and pneumonia; also, diarrhea is a significant risk factor for pneumonia. These diseases alone or co-occurring in the calves markedly increase preweaning mortality.