Assessing Colostrum Intake
Intake of good quality colostrum is important in minimising infectious disease in new-born calves, and in ensuring good live weight gains during the first 12 to 18 months of age. Inadequate colostrum intake is a relatively common finding with 33% of dairy calves across NZ and up to 80% of animals on individual farms showing failure of passive transfer (FPT) (1). Encourage your farmers to check that their calves do not fall within the latter group!
Traditionally, we have assessed GGT activity as an indicator of colostrum intake and/or failure of passive transfer (FPT). While GGT indicates the volume of colostrum ingested it doesnt determine colostral quality and calves may be at risk of FPT with GGT that falls within the reference interval. A study by Emma Cuttance (2) and colleagues determined that total protein (TP) is more accurate than GGT in estimating immunoglobulin (IgG) concentration in normal calves, finding that TP under 52 g/l is a sensitive indicator of FPT. Note that dehydration in scouring calves may increase TP potentially giving an elevated estimate of serum IgG concentration.
The price of TP is the same as that for GGT.
Reference:
- Colostrum Management: Giving calves a great start to life Emma Cuttance, Veterinary Enterprises, and Katie Denholm, Anexa Dairy NZ https://www.dairynz.co.nz/media/4439069/tech-series-june-2016-colostrum-management.pdf
- Comparison of diagnostic tests for determining the prevalence of failure of passive transfer in New Zealand dairy calves EL Cuttance, WA Mason, KS Denholm and RA Laven. NZV J 65(1), 6-13, 2017