As any cattleman knows, the time of year when cows calve directly affects many herd management practices: The start of calving is dictated by the start of breeding. So while the 12 hour rule is still valid, we now know there is a range of optimum times to breed. Heterosis or hybrid vigor is an advantage in performance of crossbreds compared to the average performance of the parental breeds. For a cow to calve at the same time each year she must mate by day 84 after calving or else she will calve later than the previous year. Just consider the Ovsynch program where cows are handled four times. These factors, either singly or in combination, result in low fertility. In general, the information can be applied to herds in the eastern, southeastern, south central and southern regions of Texas. It can be concluded that high temperatures are very stressful on summer-born calves and will reduce their growth. Since you are inexperienced, don’t do it. However, the modern dairy cow shows heat less intensely (fewer than 50% of cows in oestrus stand to be mounted compared to >70% in the 1980s) and shows it for a shorter period of time (duration of standing oestrus has decreased from an average of 15 hours to 5 hours), so the question is often asked as to whether the am/pm rule needs to be changed. intervals of eight to 16 hours after the onset of high activity and trended lower for both earlier and later A.I. If the probability of correctly treating a cow (finding and injecting her with the appropriate product on the correct day) is 95 percent, then the probability that all cows are handled correctly at each of four handlings is only 81.4 percent (0.95 x 0.95 x 0.95 x 0.95). You must feed and care for the bulls between the breeding seasons. When you have everything riding on that one cow, a year is a long time to bet you’re observations are accurate. Several years ago, I conducted a field study modeled after a dairy cow project performed by Dr. Ray Nebel at Virginia PolyTechnic. The other interesting fact is that this study was performed on bos taurus cows only. Data from an Arkansas trial show that calf performance and profits are best in small to medium frame cows that calve in the fall compared to spring months. It could increase the chances that the most fertile cows will conceive and ensure high pregnancy rates. for a while, the advantages are clear. Most can start out with either commercial or purebred beef cattle. Peak performance occurred in calves born in March (Trails 1 and 2) or April (Trial 3) and declined for all calves born from May through September by as much as 56 (Trial 1), 79 (Trial 2), and 124 (Trial 3) pounds. It is likely to be less expensive to start with yearling heifers and get them bred at 15 months of age, then calve them out as your first beef cattle. Historical cull-cow markets reach a low point in November, which coincides with the time most producers would wean calves and pregnancy check cows. lactation) thus increasing feed costs. What about bos indicus cattle? The cornerstone of my AI breeding program is: breed in a window between 6 to 8 hours following when you observe a standing heat. This is completely contrary to the effects of cold on performance in winter-born calves in northern states where temperatures are more severe and high death loss and the potential for low growth rate in calves are major concerns. For best results, observations should occur at least once in the early to mid-morning, early afternoon and later in the evening. Effects of Cow Size on Choosing When to Calf, Choosing the Time of Year to Breed and Calve Beef Cows in Texas, Private Applicator Training 2021; Amarillo - Potter County, Northeast Panhandle Summer Crops Conference, 2021 Central Texas horticultural education series, https://www.youtube.com/watch?v=Wc8xY2YuOfM. It is best to plan breeding season for the time of year when forage quality is at its best. The criteria for a cow to be declared in heat is 3 mounts in 4 hours with each mount being two seconds or greater. Many of us had grown up with that rule that states the best time to breed your cattle is 12 hours after onset (of course, that assumes you know when each cow actually came into heat). Start with cows, not heifers. Heat stress in cows is known to cause hormone imbalances, reduced quality of ova, early embryo death and reduced blood flow to the uterus. Your cows will need to be close together when breeding, so we have built a fence to keep our two cows from running away. The Dexter cow is one of … Download a printer-friendly version of this publication: Choosing the Time of Year to Breed and Calve Beef Cows in Texas. This stage of heat generally lasts 6 to 24 hours, 18 on average. This article will give you an answer. The best time of the year to buy commercial beef cattle is in the fall. Do you have a question -or- need to contact an expert? Now let’s take a look at the best time to breed according to the chart below. Keeping this in mind, perhaps the best approach to prepare cows for breed back, is to be proactive in their nutritional needs. We tracked how many hours had lapsed from the declared onset of heats to the actual A.I. This breed of cow is another really popular breed. A complicated problem in breeding is to determine when your cows are ready for slaughter. Begin by starting up a beef cow-calf operation. 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