Dairy Producers Banquet is Thursday, December 11 starting at 9AM. Speakers are Dr. Kirby Krogstat, our new OSU extension educator presenting “Monitoring Nutrition, Old Classics and New Technology” and “Controlling Mastitis at the Feed Bunk”. I’ve heard him speak 4 times and every time was very well presented. Dr. Brittney Davidson is a recent Ph. D graduate from the University of Wisconsin presenting; Consequences of Heat Stress in Dry Pregnant Cows, Growing Heifers, and Post Weaning Dairy Calves. We’ve known about this science for 5 years, now it is time to get it done and capitalize on the opportunities.

There sure has been a lot of talk about the weather and for good reason. It’s been hot and worse yet, it hasn’t cooled at night. We are now seeing herd checks showing the results of the weather with palpation rates of 30% pregnant in herds that usually run 80%. There are herds that are down 20 pounds in milk. The lameness and culling will come. You can’t change the weather, but you can change the way it impacts your cows. We might think we don’t have enough summer left to bother, but it’s a long time until October and we may be able to do something. The worst heat stress is in holding pens. It takes 15 minutes for cows packed together to raise their body temperature 1 degree, where they lose production and reproduction and spend more time standing. It takes 8 to 12 hours to cool cows down in a reasonably cooled barn. Then we do it again. Barn cooling is more about keeping cows from getting hot than it is about cooling cows that are already heat stressed.

It takes wiring and electricity to run fans and it takes a water supply to run a line of sprinklers. The quickest fix in the holding pen is to hang I-Wob’s. The install instructions are on the back of this newsletter. I-Wob are very durable and easily installed. They also give a good distribution pattern. Most farms move cows through the holding pen fast enough that we can run the I-Wob on ‘full open’ continuously. It would be preferred to have multiple banks of fans to blow the water off, but we can do what we can get done. Don't have a holding pen? Cool the area around the Robot entrances and you should increase visits.

Are calves and heifers suffering in this weather? Yes, hardly a day goes by lately that we don’t necropsy calves. If you have hutches, do you have all the vents open? That may not be enough and we still need to prop up the backs to let air flow through. If you prop them up, tie them down or you may have to look for calves and hutches after the next summer storm. Calf barns can benefit from cooling fans. It is possible to use cooling fans positioned to bring fresh air in from the outside. That system works less well in the winter. Health depends on ventilation and cooling. Every situation is different and we have spent much time in the last weeks saying, “I would put 56 inch fan there.” or “Your soakers will be more effective 66 inches from the ground compared to 80.”

How I Approach Calf Problems - Dr. Geoff Smith Historically we tried to raise calves cheap, but we know the opportunity for 1000-3000 pounds more milk in first lactation with a 500 to 1200 pound penalty for respiratory. Heifer survival approximates Net Farm Income. Indicators of Profit are: Milk > SSC> Heifer Survival. Beef on dairy is giving us cash now, but restricting incoming heifers, & limiting culling decisions. Currently 40% heifers to cows.

Colostrum Mgt, Housing, Hygiene are big. Remove the source of infection or remove the calf from the contaminated environment. Calves with dam >1 hr is a risk factor for Cryptosporidia. Calves dying less than 5 days of age are due to dirty colostrum or calving area. Cow numbers in calving area, bedding frequency, and observation frequency matter.