George F.W. Haenlein Extension Dairy Specialist University of Delaware OH, THAT MEXICAN INAPPETENCE! This year’s national Dairy month is over, and I have just returned from another foreign assistance assignment abroad. There are so many dairy topics I could tackle, but it is so hot right now that all I can think about is how to shut off this heat or. at least, diminish its effect People can head for air-conditioned places, but what about dairy ani mals our cows, goats, and sheep? What can they do to beat this heat? And they still must give milk two or three times a day without changing the level of out put. In a few places in Saudi Arabia, where money is no object, some Holstein herds actually enjoy air conditioning. And in Florida, be cause of some excellent develop ment work by Experiment Station engineers, cows in many com mercial herds are cooled by full showers a couple of times each hour. 1 am not the only one thinking about the heat and its effects. Just look how many magazine and journal articles cover hot weather, heat stress and what to do about it At the risk of taking “coals to New Castle" or “owls to Athens,” I will add a few ideas of my own, which include reviews of new research. The long ears of tropical Brah ma or Zebu cattle and of Nubian dairy goats function successfully as radiators in hot weather, en- Dairy of WM Distinction A Ist Class Team (f/- 'IV, Together For 25 Years! [ fjlfflfm aotmorol Milk IS the real thing' A e*°® AKER R * FR, oe* IMII Scroll-Compressor Technology yW tH&tf fttty te4A fat 46HtC 1 dotty, fatm eftUfuH«Ht... ' # cM ill llnlnuU « l-lh ku lor IJ IKK) Ills Ml,lk iti\ t. r Total operating coot for ten yean Savings Southern Service Center 76 Pumping Station Rd. Quarryvllla, Pa. 717-786-1617 Vic telnlnger ★ Call Today For All Yi DAIRY MANAGEMENT COLUMN abling those animals to get some relief from the heat. Northern cli mate cows, such as Holsteins, Guernseys and Ayrshires (and Swiss dairy goats), have short, erect ears, so they suffer because they have no such cooling mechanism. A little-known fact, however, is that the horns of dairy goats are highly vascularized that is, full of blood vessels. Homs serve as a cooling mechanism for Swiss goats, thus reducing the tempera ture of the brain by 2 degrees below the average body tempera ture. This is significant, because the control center for eating or not eating is in the brain. The primary consequence of hot weather is a reduction in feed intake, yet a common U.S. dairy management practice is to dehorn calves and goat kids, thus depriving these animals of that potential cooling mechanism-. When it comes to hot summer days, dairy farmers worry that their dairy animals lie around in the shade and do not eat As a re sult milk yield drops as much as 35 percent per day, total lactation decreases, and ovulation or estrus halts. Holsteins, Guernseys, Ayr shires and Swiss goats suffer when temperatures go above 80 degrees Fahrenheit. Jerseys, Brown Swiss and Nubian goats have a slightly higher tolerance level. What can dairy fanners do? Recent research in Missouri C Journal of Dairy Science 80 (1997) 1206-1206) examined the benefit of adding niacin at 12, 24 or 36 gram/day/cow on heat stress. We Congratulate all the 1997 Dairy of Distinction Award Winners DAIRY FARM EQUIPMENT Offer * Contact your Mutllwr distributor lor (urthor comparisons Mut lie r ( ompitition Ml (KM I S.'SIMKI >22 Mill s 2 ■UK) MAIN OFFICE 1048 North Penryn Rd. Manheim, Pa. 17545 717-665-3525 Ken or Ed Brubaker 'our New or Used Milk Tank And Refrigerel This B vitamin dilates blood ves sels, thereby aiding in the skin peripheral cooling of cows on hot days. They found that cows’ skin was cooler and their milk produc tion slightly higher, but the most important problem, feed intake, was not improved. Other new research in Arizona (Journal of Dairy Science 80 (1997) 1172-1178) included per iodic water showers and air fans for cows in addition to feeding ex tra (3 percent) supplementary fat per diet dry matter. The idea is to reduce heat generation from eat ing a normal feed ration by in creasing its nutrient density with fat, thus providing more energy with less volume of feed. Results showed how difficult it is to help heat-stressed cows by way of feeding—they just do not want to eat as much as usual. The cows know instinctively that eating makes them more hot. Cows suffer from what I like to call “Mexican Inappetence” syn drome. It sounds better than just saying “reduced voluntary feed intake” or “heat-stress-induced lower feed consumption.” All it means is that dairy animals have no appetite for anything. And just as our cold winter storms come across Canada on the “Canadian Clipper.” the hot winds originate in the Gulf of Mexico there fore, “Mexican Inappetence.” Research in Arizona showed that while the manipulation of the ration in the right direction, physiologically, did not help hot cows sufficiently, but a milk prod uction increase of more than S *x> Northern Service Center 541 Frystown Rd. Myerstown, Pa. 717-933-4711 Ken Kopp itlon Equipment Needs! •PtttiweMmiauplamm tetUnßtite? Dairy of U Distinction KING CONSTRUCTION CO, - Specializing In Free-Stall Bams! Heifer Bams And Parlors 6 Row Freestall Barn KING CONSTRUCTION CO. 601 Overly Grove Rd., New Holland, PA 17557 (717) 354-4740 • Phil Van Lieu - Home (717)259-9077 pounds/day/cow and increased feed intake was achieved with per iodic showers and air fans. To be of any value, shower cooling must take place where cows spend most of their time: 1) where they eat sil age or a total mixed ration (TMR), and 2) in the holding pen. As cows wait to be milked, they crowd to gether and get overheated. We have done both at the University of Delaware dairy bam with good success. Other good advice comes from the Georgia and Kansas Experi ment Stations on how to overcome that inappetence of dairy animals when the hot air from the Gulf of Mexico stagnates here: • Don’t walk cows long dis tances. • Provide clean, cool water, even out in the pasture! • Reduce roughage to 40 per cent of total ration dry matter. • Increase eneigy and protein density of the ration. • Adding 1 pound fat can reduce S* y H Distinction Congratulations To The Dairy Of Distinction Winners! WE BUILD IN PA, MD, DE & NJ the grain ration by 2.25 pounds. ■ Keep ration fat contents as high as 6.0 percent • Make ration protein levels about 20 percent • Keep potassium ration con tents between 1.3-1.5 percent • Limit grazing to early morn ing and evening. ■ Shower and fan cows—regu larly and frequently—where thev congregate as soon as the temperature reaches 80 degrees F. • Feed TMR several times per day for better freshness. • Moisten TMR to 45-50 per cent water contents for improved intake. • Clean feed bunks daily and re move leftovers. • Use rumen buffers to control acidosis. If you follow these tips for tak ing the heat off your milking ani mals, they will lose that inappe tence, and you will reap the finan cial benefits.