Influence of Shipping Container, Preservative, and Breed on Analysis of Milk Components of Shipped Samples

Abstract

An average of 50 milk samples from Holsteins and 16 samples from Jersey cows were collected monthly for 11 mo and allocated to one of four treatments: 1) preserved with potassium dichromate and shipped in plastic bags, 2) preserved with bronopol and shipped in plastic bags, 3) preserved with potassium dichromate and shipped in plastic vials, and 4) preserved with bronopol and shipped in plastic vials. Samples were shipped to a DHIA laboratory for determination of milk fat, milk protein, and SCC. Samples shipped in vials preserved with bronopol were statistically higher in milk fat. Overall, milk fat was higher in samples shipped in vials than in those shipped in bags and in shipped samples preserved with bronopol than in those preserved with potassium dichromate. Milk protein was lower for samples shipped in vials than for those shipped in bags but was higher for samples preserved with bronopol than with potassium dichromate. Effects of containers and preservatives were not different for SCC. Overall, shipment of samples in plastic vials using bronopol as a preservative yielded the highest results for the analysis of milk fat, and milk protein and SCC.