D52-Lancaster Farming, Saturday, July 20,1991 Dairy Tips By Dr. Randy Lyle, Ph.D. If Pennsylvania temperatures continue on their May - June pattern, you can be sure that cows will be looking for a cool place to hide all summer. The common situation on most dairy farms that I’ve seen in this area is that there are few, if any, cool places for cows to hide. Cows usually are much apprecia tive if they are offered some relief from the summer heat and humidity. They have been known to return the favor by giving their owners more milk, and also by rebreeding easier and more quickly. This summer, I will present a series of articles on how to minimize heat stress in dairy cows. Let’s first begin by discussing heat stress in general terms. Cows most enjoy temperatures between 45 and 55 degrees. When temperatures reach 75 or 80 degrees, they become stressed. Rumen fermentation generates a great amount of heat, thus requiring cows to dissipate more heat than non-ruminants. In addition to the heat produced in the rumen, other sources of WARRIOR’S MARK FEED CENTER P.O. Box #l3O Warriors Mark, PA 16877 814/632-5490 FARMER’S UNION CO-OP 30 East Walters Avenue Greencastle, PA 17225 717/597-3191 K 4 K FEED, INC. 23 N. Park Street Richland, PA 17087 717/866-2324 H.R. WENTZEL SONS., INC. Box 6 Bloomfield Ave. Newport, PA 17074 717/789-3306 THE OXFORD GRAIN & HAY CO. 1212 Railroad Ave. Oxford, PA 19363 215/932-8! >2l BEDFORD FARM BUREAU Bedford PA 814/623-6194 Everett, PA 814/652-2313 New Enterprise, PA 814/766-3329 ANTHONY’S FEED MILL P.O. Box 212 Strausstown, PA 19559 215/488-6211 * Trademark of Ralston Purina Company HOT COWS IN THE SUMMERTIME Contact Your Purina Dealer Today kssANlls rHECKRBDABn Paradise, PA 17562 „ 239 Yf -717/442-4183 Knoxville, PA 16928 717/768-3301 814/326-4178 Unlonvllle, PA 19375 215/347-2377 UMBERGER’S MILL R.D. #4 - Box #545 Lebanon, PA 17042 717/867-5161 GLENVILLE FARM CENTER Glenville, PA 17329 717/235-1290 FRANKLIN FEED & SUPPLY 1977 Philadelphia Ave. Chambersburg, PA 717/264-6148 5960 Altenwald Rd. Waynesboro, PA DETRICH ELEVATOR, INC. 5458 Cedar St. Williamson, PA 17270 717/369-3724 WILLIAM GOWER & SON Rt 1, Box 50 Williamsport, MO 21795 heat gain are associated with physical activity, basal metabolism, and radiative (solar) heat gain. Cows attempt to keep cool by losing as much, or more, heat than they gain. Cows demon strating the following behavior are heat stress ed: 1) increased rate of respiration and per spiration; 2) lying flat on cool surfaces, such as bedding or the ground; 3) decreased feed intakes; 4) increased water intakes. Blood flow distribution is also altered, favoring peripheral circulation, but most people can’t see this change. If cows can’t dissipate all of the heat gain by the above behavioral changes, their body temperatures rise further, thereby causing feed intakes to dramatically drop. This is when cows really get . stingy with the milk and go on strike. If severe enough, the last symptom of heat stress is death. In my next article, I’ll discuss some manage ment tips that will help cows keep their cool, and tolerate the summer heat. HIGH BROTHERS 441 Centerville Road Gordonvllle, PA 17529 717/354-0301 H.C. SUMMERS, INC. 4002 Jefferson Pike Jefferson, MO 301/473-8300 M.G. HENNINGER & SON, INC. Berrysburg, PA 17005 717/362-3333 WOODSTOWN ICE & COAL CO., INC. 50 East Grant Street Woodstown, NJ 06098 609/769-0069 OLEY VALLEY FEED RD2 • Box 271 A Oley, PA 215/987-3568 MARTIN S FEED i FERTILIZER, INC. Coburn, PA 16832 814/349-8787 Feeds designed with you in mind. PURINA MILLS, INC Purina Mills Dairy Consultant SPENCER’S MILLING SERVICE 306 S. Rodney St. Clayton, DE 19938 302/653-8011 NISSLEY FEED CENTER Mill Rd., Box 377 Morgantown, PA 19543 215/286-9029 TRI COUNTY AG CENTER, INC. McVeytown, PA 17051 717/899-8772 R D BOWMAN & SONS, INC. Englar Rd Westminster, MD 21157 301/848-3733 NORTH GLADE FEED & SUPPLY, INC. 12435-A Woodsboro Pike Keymar, MD 21757 301/898-3414 PURINA MILLS, INC ■ ■
Significant historical Pennsylvania newspapers