May 11, 2020
Signs of recovery in beef packing… but how fast?
By Derrell S. Peel, Oklahoma State University Extension livestock marketing specialist
COVID-19 began impacting workers at beef packing plants in early April. In the last five weeks, cattle slaughter decreased by an average of 27% year over year. This compares to the previous five weeks in March, when cattle slaughter averaged 5.5% higher than year-ago levels. The impacts got progressively worse for four weeks with weekly slaughter dropping by 17.1% the week of April 11 to a decrease of 36.8% year over year in the week ending May 2.
There is glimmer of hope, however. Last week estimated cattle slaughter was 452,000 head, still down 32.2% year over year, but up 6.4% from the prior week. This hopefully indicates the beginning of recovery of packing capacity in the coming weeks. Risks remain, however, and it is not clear how fast packing plant capacity will recover. New safety measures and work protocols likely mean that effective maximum capacity in beef packing plants will be reduced compared to pre-COVID-19 levels.
It will likely take many weeks for slaughter rates to catch up with the growing backlog of fed cattle and get the industry current once again. Meantime, all sectors of the industry are responding to the need to slow cattle down and hold them longer in a variety of production settings before proceeding to finish in feedlots. Fed cattle weights are increasing and pushing carcass weights higher counter-seasonally. The latest actual weekly slaughter shows steer carcass weights at 891 pounds, higher than the three prior weeks and up 37 pounds from the same period last year. Heifer carcasses are currently 24 pounds heavier year over year. Steer and heifer carcass weights typically reach a seasonal low in late May.
Beef production dropped sharply in April resulting in some shortages of fresh beef in retail grocery stores and restaurants. In the five weeks ending May 9, total beef production was down nearly 690 million pounds year over year. In the worst week ending May 2, estimated total beef production was 347.1 million pounds, down 190.5 million pounds from the same week last year. Estimated beef production last week was down 31% year over year but was up 5.9% from the prior week, reflecting the slight increase in cattle slaughter last week.
Total 2020 beef production forecasts have only been slightly reduced from previous projections and are still at or near a record level of 27.2 billion pounds. However, the timing during the year is drastically altered with second quarter beef production forecast down 13.3% year over year. Beef production will be pushed into the third quarter, which is forecast to be up 5.4 percent compared to last year. Fourth quarter beef production is currently forecast to be just slightly higher year over year.
Realistic expectations for estrus synchronization and AI programs
By Glenn Selk, Oklahoma State University Emeritus Extension animal scientist
Producers that are wanting to improve the genetic makeup of their beef herds very often turn to artificial insemination (AI) as a tool to accomplish that goal. Many times, these producers have very high expectations as they begin the first season of artificial breeding. Perhaps they have heard other producers tell of situations where “near-perfect” pregnancy rates resulted from THEIR artificial insemination program. Everyone wants to get every cow or heifer bred as they start the labor and expense of an AI program. However, the rules of biology do not often allow for 100% pregnancy rates in most situations.
First of all, it is important to understand several terms.
Estrous response rate: the percentage of cows found to be cycling in response to an estrus synchronization protocol. In other words, if we put 100 cows through the working chute and give them estrus synchronization drugs, and only 80 of those cows responded to the estrus synchronization products, then we have an “estrous response rate” of 80%.
Perhaps some of the cows were not “ready” because they were later calving or they were in poorer body condition. If we are breeding only after they are detected in heat, then only 80 of the original 100 cows would be bred to AI after standing heat. If “timed AI” is the method of choice (in this scenario) only 80 of the cows would be in a biologically suitable stage of a heat cycle to have a chance to conceive. Replacement heifers that are slightly too young, or too lightweight may not be available to respond to the synchronization protocol and therefore unlikely to conceive to insemination.
Conception rate: the percentage of the cows that were actually cycling, then inseminated and were palpated later and found to be pregnant to AI breeding. In other words, of the 80 cows in the above example, that were found in heat and inseminated, IF we later found that 70% of those “settled” or became pregnant, we would have found 56 cows pregnant. Experienced AI technicians often achieve 70% conception rates. Semen quality must be adequate. Also, semen handling techniques must be appropriate in order to expect 70% conception rates.
AI Pregnancy rate: the percentage of cows that were initially started on the estrous synchronization protocol that actually became pregnant. In the above example, 56 of the original 100 cows became pregnant to the AI program, resulting in a pregnancy rate of 56%.
Therefore, the Estrous response rate X Conception rate = AI Pregnancy rate.
In this example: 80% Estrous response X 70% Conception = 56% Pregnant to artificial insemination. The above example is hypothetical, yet very much close to the expected outcome of a successful synchronization and AI program. If heat detection is incorporated as part of the system, then it becomes another very important part of the equation.
Research conducted that evaluated different synchronization protocols very often illustrated variables other than protocol were most important. Differences in body condition of the cattle, experience and skill of the AI technicians, and weather influences, often played larger roles in the pregnancy rates than did the synchronization protocol. There was more difference expressed between operations than between the synchronization methods chosen.
Help in choosing the synchronization protocol that best suits your situation can be found courtesy of the Applied Reproductive Task Force. This group of scientists list preferred protocols for both replacement heifers and adult cows.
After artificial insemination is conducted on the cows or heifers, clean up bulls will be introduced to the breeding pasture to breed those females that did not conceive to AI. How many clean up bulls are needed?
University of Nebraska researchers (Nielson and Funston, 2016) have published a review on beef AI trials and have evaluated the reported cow to bull ratios used in the clean up portion of the breeding seasons. They grouped the trials into three categories based on the cow to bull ratios used.
Final pregnancy rates for cow to bull ratios of 1:20 to 30, 1:31 to 49, or 1:50 to 60 were 87.8, 82.6, and 89.2%, respectively. These ratios are based on the number of cows entering the estrus synchronization and AI breeding season. The fact that the wider cow to bull ratio was as successful as the others should not be surprising. Half or more of the cows were already bred when the bulls were introduced and therefore an actual number of cycling cows to bull ratio was actually near 25:1.
In addition, estrus synchrony on the subsequent heat cycles was not as tightly synchronized as the first heat at AI. Natural variation in cycle lengths will cause less synchrony and therefore less intense breeding pressure on the cleanup bulls.
Cow-Calf Corner is a weekly newsletter by the Oklahoma Cooperative Extension Agency.