Evaluation of the Brix refractometer as an on‐farm tool for the detection of passive transfer of immunity in dairy calves

Abstract

Brix refractometer score ≥10% can be used to classify calves with successful transfer of passive immunity and the devices are sufficiently accurate for use as a simple, inexpensive on-farm tool for the monitoring of neonatal dairy calf immunity levels.

Evaluation of 5 methods for diagnosing failure of passive transfer in 160 Holstein calves

“…Our findings were in agreement with those reported elsewhere, but in contrast with those of 4 other studies that evaluated the Brix refractometer . The different results might be due to variations in sample volume or temperature relative to the refractometer temperature, as the Brix refractometer used in this study was temperature compensated.…”

“…Our findings were in agreement with those reported elsewhere, 22 but in contrast with those of 4 other studies that evaluated the Brix refractometer. 14,26,27,43 proposed to reduce errors due to hemolysis. 16 There are some limitations to our study.…”

“…Second, the prevalence of FTPI in the present study was low at 13% (20/160) when compared with that reported in recent studies. 14,16,26,43 We attribute the low FTPI prevalence to the colostral feeding protocol used at the dairy; administration of 3 L of good-quality fresh colostrum (total IgG concentrations >50 g/L) within 2 hours of birth. 4…”

“…A digital Brix refractometer has been used as an on-farm tool to evaluate colostrum quality, 23,24 and considerable value exists in using the same instrument to also evaluate FTPI in calves. 22 Accordingly, studies were conducted to evaluate the clinical utility of using a digital Brix refractometer to evaluate FTPI using serum samples, 14,22,25,26 with a digital Brix value of <7.8%, <8.3%, <8.4%, <8.6%, or <8.8% used as cut points. 14,22,25,27,28 The first objective of the study reported here was to compare the performance of the 5 indirect methods for detecting FTPI in Holstein calves.…”

In this issue – January/February 2015

“…A Brix refractometer may be a suitable on‐farm tool for dairy farmers to identify calves with inadequate levels of immunity within 24 h of birth so that they could feed high‐quality supplementary colostrum …”