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Milk Quality and Milk Components in Lactating Dairy Goats Fed OmniGen-AF® from Dry Off Through the Entire Lactation
In the United States the legal somatic cell count (SCC) limit for dairy goat milk is 1,500,000 ml-1. However, it is common for SCC to be much higher than this. Production of milk with a SCC higher than the legal limit results in farms being unable to ship their milk and lost income. The objective of this study was to evaluate the supplementation of OmniGen-AF® to dry and lactating dairy goats on milk quality and milk components over an entire lactation. Thirty-five, two year old does housed on a commercial goat dairy located in south-central Wisconsin were randomly assigned to one of two groups: 1) Control-fed (n=18), and 2) OmniGen-AF-fed (n=17). Animals in Group 1 were fed a complete feed pellet twice a day and ad libitum alfalfa hay. Animals in Group 2 were fed the same diet but with 6 g/h/d of OmniGen-AF added to the pellet. The project started at dry-off (approximately 40-60 days prior to kidding) and continued for the full lactation. Breeds of does were Alpine, Saanan, Nubian and La Mancha and all breeds were equally represented in both groups. Monthly Dairy Herd Improvement Association (DHIA) milk testing was performed on all animals for nine months. SCC, percent milk fat, percent milk protein and milk production data were collected at each test. The mean SCC for OmniGen-AF-supplemented does was 585,000 ml-1 which was significantly lower (P < 0.05) than the mean SCC for control-fed does which was 894,600 ml-1. These differences were more pronounced as does approached the end of lactation where the mean SCC was 1,669,000 ml-1 lower in OmniGen-AF-fed does compared to controls (2,094,000 ml-1 vs. 3,763,000 ml-1, respectively). Milk percent fat (P < 0.01) and percent protein (P< 0.05) were different between the OmniGen-AF-fed and control-fed does. Specifically, mean milk percent fat from control-fed does was 3.21% and 3.45% from OmniGen-AF-fed does. Mean milk percent protein was 2.93% and 3.08% from control and OmniGen-AF-fed does, respectively. There was no difference in milk production between groups. Data from this trial demonstrate that OmniGen-AF fed goats experienced benefits in milk components and attenuation of the dramatic increase in SCC that normally occurs late in lactation, both of which are indicative of improved mammary gland health.
Keywords:
Goats, OmniGen-AF, SCC