Investigation of brix refractometry for estimating bovine colostrum immunoglobulin G concentration

Abstract

Many dairy operations uses a Brix refractometer to assess the quality of first-milking colostrum. This study investigated whether a digital Brix refractometer could be used in a model to predict colostrum IgG concentration and whether more than one %Brix threshold could be used for different colostrum IgG concentrations. Colostrum from 182 animals was tested using a digital Brix refractometer and by single radial immunodiffusion. Statistical analysis, using simple linear regression to relate %Brix results with corresponding colostral IgG concentration, and receiver operating characteristic (ROC) analysis were used to identify %Brix cutoffs that had no false positive results. Colostral IgG concentrations from digital Brix refractometry had a R2 value of 0.818 and a S-value of 21.7 g/L. The large S-value shows that a digital Brix refractometer should not be used in a model to predict colostrum IgG concentration. However, %Brix scores of 19.0, 22.0, 25.0 and 30.0 percent can be used to estimate minimum colostral IgG concentrations of 25, 50, 75 and 100 g/L. These four cutoffs can be used to strategically feed smaller volumes of colostrum to newborn calves. Smaller volumes may reduce unwanted side effects and shorten the time interval in which calves refuse to nurse, while still delivering an adequate mass of IgG to have successful transfer of passive immunity.

Severe colic in a newborn dairy calf caused by a large colostrum curd: a case report

“…The calf care providers for this case followed on-farm protocols for colostrum feeding that are based on current best practice recommendations for the industry (1,20). Previous publications have suggested that feeding a smaller volume of colostrum is preferable because there is a higher efficiency of absorption of bovine immunoglobulin (21)(22)(23)(24).…”

“…In Europe, force-feeding colostrum using an esophageal tube feeder can be controversial and, in some countries, tube feeding is prohibited except for medical reasons (28). Abdominal distension and colic caused by large-volume colostrum feeding can be mitigated by gaining further knowledge of how to appropriately assess colostrum quality (20). Additionally, calf care providers can be trained on the appropriate administration of colostrum, which includes identification of the risks and complications of overfeeding with an esophageal tube feeder (7)(8)(9)20).…”

“…Janssen et al, who reviewed the role of gastric motility in humans as a central component of hunger and satiety, reported that distention (by nutrient or non-nutrient meals, or by intragastric ballooning) of the human monogastric stomach induced a satiating effect that ranged from sensations of feeling full to feeling pain ( 18 , 19 ). In addition, some calf care providers and veterinarians have observed that female, Holstein calves that are fed large volumes (≥4 L) of colostrum for the first meal, often will not nurse for 18–36 h post-colostrum feeding ( 20 ). The health effects and potential risks for newborn calves with an extended lapse in time between meals are unknown at this time, and further investigation is needed.…”

Colostrum Replacement and Serum IgG Concentrations in Beef Calves Delivered by Elective Cesarean Section

“…Thirty-two multisource, crossbreed, multiparous beef cows [ 20 ] and first-calf heifers [ 12 ] were enrolled in this study from February 2017 through March 2018. Cows and heifers were synchronized with a modified 7-d CIDR-synch protocol and artificially inseminated (AI) as previously described [ 22 ].…”

“…Recommendations for colostrum replacement in dairy calves call for the administration of a high volume (~4 L) of high-quality (>22% Brix) maternal colostrum or colostrum replacer powder (300 g of IgG) within the first 2–4 h of birth [ 16 , 17 ]. These recommendations may be impractical for beef calves for several reasons, including lack of complete separation of the dam, excessive volume in relation to calf body weight, potential disruption of nursing behavior due to gastrointestinal distention, and colic [ 18 , 19 , 20 ]. The overarching goal of colostrum supplementation and/or replacement in beef calves should be to minimize the negative impact of FTPI and ITPI while avoiding disruption of normal nursing behavior [ 18 , 21 ].…”