Comparison of Colostrum Replacer and Maternal Colostrum: Jersey & JerseyXHolstein Calves.
"The objective of this study was to determine the effect of feeding a commercially available colostrum replacer versus pooled maternal colostrum on immunological status, growth and health in preweaned calves." (p1345)
Bottom Line - colostrum replacer works if you don't have clean maternal colostrum to feed.
Colostrum management - all the calves (N=1215) were fed at least 150g of IgG within 1 hour of birth. And both the colostrum replacer and maternal colostrum had either no or very very low bacteria counts.
Note here that these calves were only fed colostrum once. And they were limited to only 150g of IgG. I recommend to my clients to include 200g IgG first feeding and to consider a second feeding 6 to 12 hours after the first feeding of another 100-200g IgG. So, consider these calves as getting the "basic" volume of IgG.
Efficiency of absorption of antibodies - GREAT! If you feed enough high quality colostrum (or replacer) within an hour after birth the body does a good job of moving antibodies from the gut into the blood. Both colostrum and replacer had efficiency rates in the range of 34 to 36%. Those are good numbers.
Total protein values? Both averaged above 5.0. Colostrum replacer average value was 5.2 and maternal colostrum average value was 5.8. These are good numbers considering that IgG intake was limited to only 150g IgG.
Calf Growth The calves were limited to only 4 quarts of non-salable milk per day. The growth rates were 0.7#/day for colostrum replacer calves and 0.8#/day for maternal colostrum calves. These calves with a limited supply of nutrients from milk increased their weight from birth to weaning by 62% for colostrum replacer and 65% for maternal colostrum.
Note here as an industry growth standard I have adopted the national Dairy Calf & Heifer Association goal of doubling birth weight in 8 weeks. My clients that feed 2 pounds of milk replacer powder or 4 gallons of whole milk daily routinely average 1.7#/day gain at 56 days.
Health Including diarrhea, respiratory disease and fever there were no differences between colostrum replacer and maternal colostrum calves.
Mortality - The national standard from the Dairy Calf & Heifer Association for mortality under 8 weeks is less than 5%. Maternal-colostrum treatment calves had a 7.1% death rate while the colostrum-replacer treatment calves had a death rate of 9.4%. We can only guess that there were stressful circumstances (for example, weather, hygiene) that resulted in these elevated mortality rates.
Reference: Lago, A. and Others, "Efficacy of colostrum replacer versus maternal colostrum on immulogical status, health and growth of preweaned calves." Journal of Dairy Science 101:1344-1354 February 2018.