Early weaning of calves during droughts can have many benefits to the dairy herd such as improved body condition of cows, improved regeneration rates, increased forage availability, and potentially improved calf performance. However, increased management is critical for young calves and several factors should be considered before making this decision.

The most successful early weaning programs begin with healthy calves prior to weaning. Calf age plays a critical role in early weaning. Animal health procedures performed prior to weaning will help ensure calf health through the weaning transition. In a recent nationwide survey of veterinary practices, the largest number of respondents (38%) recommended weaning calves at an earliest age of 90-120 days (Fike et al.). Consulting with your local veterinarian to help establish a health protocol to help improve calf health while reducing stress will be very beneficial in the case of early weaning.

It is also important to understand the immune function of the calf during this period. Calves are born with a fully functional immune system, but they do not yet respond to any pathogens. Ingestion of colostrum shortly after birth helps fill the gap and provide passive immunity with immune cells and antibodies that play a role in natural immune function early in life. At 2 to 4 months of age, maternal antibodies are key players in the immune protection of the calf. This plays a major role in how the young calf responds to immune challenges such as vaccines. When these maternal antibodies begin to wane, it is prime time to initiate a vaccine regimen to help boost the calf's active immune protection. While every calf may not fully respond to vaccines at this age, vaccination can give the immune system a booster later in life.

Multiple stressors and declining health occur simultaneously. Painful procedures such as castration, dehorning, and branding should be performed prior to weaning. Handling calves prior to weaning is important and there are opportunities to include many "pre-treatment" type practices to help ensure the calf is healthy.

Initial vaccinations and management procedures such as castration should be performed 2-3 weeks prior to weaning. During this time, control for other stressors such as external parasites and internal parasites can be initiated. During the summer months, external parasites are primarily flies. Internal parasite control should target gastrointestinal nematodes (worms) as well as coccidiosis during this stressful period.

To further enhance calf comfort, developing a program to control heat stress and reduce dust can be very helpful in ensuring the overall health, performance and welfare of these calves.

link: https://www.bxlimage.com/nw/733.html