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Show 2 Farm & April Ranch Edition Emery Animal Health Update 2002 Management Cow-Ca- lf Does Size Really matter The one factor that can de- termine economic returns more than anything else is re- productive efficiency. What does this mean? Well it does mean that you have to get a calf on the ground, hut it is much, much more. To be truly efficient, a cow needs to have her first calf when she reaches 24 months of age. Then calve again 36S days later, repeating this for the next 10 or so years. Each cow in the herd needs to accomplish this task. At least SO percent of the herd needs to calve within the first 18 days of the calving season, and all cattle should calve in less than 63 days. So, does your choice of a bull have anything to do with this and what trait seems to correlate well with reproductive efficiency? Scrotal circumference, the size of the bulls testicles. Large scrotal circumference gives the bull the capacity to breed more cattle, and get them bred early. There is a high correlation between scrotal circumference and fertility in bulls. Not only are the numbers of sperm greater, but motility and morphology also score more favorably. Bulls with above av- erage yearling testicular size sire daughters that reach puberty earlier and have greater lifetime reproductive potential. Bull calves also have a bigger scrotal circumference and mature earlier. While scrotal circumference is important at any age, it is best to compare sizes with adjusted yearling data. This makes it possible to compare data fairly from one bull to the next. If scrotal circumference is not adjusted to yearling data the comparisons may not be accurate. When a scrotal circumference is measured it is important to have it done correctly to insure accurate results. It is best to obtain the measurement as close to a year old as possible when using yearling scrotal circumference. Then this number must be adjusted to a 365 days for fair comparisons. The temperature needs to be over 32' F and proper technique used. Reproductive traits are critical to the profitability of entera commercial cow-ca- lf twice as prise, important as a production trait such as weaning weight or carcass merit. The use of yearling scrotal circumference is the best indicator of genetic potential reproductive performance when choosing bulls to place in your herd. Yearling sizes more closely correlate with reproductive performance in offspring than it does when the bull is What else did you purchase with that new animal addition? Reproductive losses come fully grown. in many packages. Some asymptomatic cattle. That means you may have one or more cows shedding the virus to other cattle, yet never show any sign of infection in indluce, cattle not cycinge do to young age, nutrition, stress, and short time postpartum. Abortions can occur from the time a cow is bred until calving. This is because of diseases, toxins, stress, and other unknown causes. Early calf deaths usually in the first week of life can also take a big toll on a producers calf crop. While some problems may be out of our control, there is more that most producers can do to help prevent and eliminate potential problems. Bovine virus diarrhea (BVD) and infectious bovine rhinotracheitis (IBR) are abortion causing diseases that can also be found in the persistently infected (PI) animal Bulls can be a source of persistently infected (PI) cattle. The viruses are shed in body fluid including the semen. Prevalence of PI for BVD is estimated at 2 - 3 percent That means if you purchase 20 head of replacements you have a 30 percent chance of having one PI animal Persistently infected animals are not found in all herds, other herds could have Continued an page 4 EMERY ANIMAlfHEAIiFH Large and Shudh Animal and AUTO PARTS Foreign and Embrvo 3 Computerized 4 - - A . Transfef $) Cash Discount on Cattle (500 Great Bargains on Used Vehidei eel Alignments See us for all your automotive needs. Jacks Motor Service 399 N. Main, Huntington 687-228- 8 We Feature Vaccines and Dectomax Ivormectrin Apple Flavored Treats & Liquid Starts at $5.00 per dosemilper horse AUTO SALES Domestic BF GOODRICH TIRES Lowest PhcttV foe area. Cattle & Horse Dewormers and VacdnatlonS Now Introducing & Wlx V ' Filters 470 Castle D4& Utalr84513Hr order) a.t WIX HEJ5WEAT THE SMALL STUFF. |