The dairy industry continues to evolve. The advent of sexed semen gave dairy farms the opportunity to greatly increase the odds of getting heifers from the genetically superior cows, therefore increasing overall heifer inventory in the herd. Recently, dairy farms have diversified into the beef industry as cull cow and calf sales have been a welcome addition to the year’s cash flow. Beef on dairy crosses have become more popular and have delivered a substantial economic boost to the dairy producer’s profits.
Both trends can be a great opportunity for the dairy industry but also have associated risks. Some dairy farmers found themselves with an overabundance of replacement heifers when using too high a percentage of sexed semen versus conventional. This has put a strain on facilities with overcrowding and is a financial drain as those heifers mature. More recently, the extremely high prices for crossbred calves have convinced people to breed more cows to beef and have created a shortage of replacements on some farms. Remember, that from the time a cow is bred to her calf entering the lactating barn, it will take about 3 years. Due to this, it is important for farmers to plan ahead. Farmers should evaluate their replacement needs and plan their breeding program accordingly each year.
Many factors are involved in calculating the requirement for replacements. A farm trying to grow herd size internally will have a different strategy versus an overcrowded farm attempting to limit growth. Cull rates, reproductive management, and heifer management all have a direct influence on the number of heifers needed in a year.
A shortage of replacements can lead to empty stalls and decreased yearly production. Additionally, economically unproductive cows may not be culled to maintain cow numbers if there is not a genetically superior animal available to fill her spot. Having to purchase replacements produces an economic cost but also raises biosecurity issues. It is possible for animals to develop illness after the stress of trucking, the introduction to a new facility, new cows, and a new diet. Even more costly is the risk that apparently healthy purchased animals can introduce a disease into the home herd. Both situations can lead to risk with loss of production, veterinary costs, and potential death loss.
Raising too many replacements also carries significant risks. On many farms, keeping an excess number of replacements results in overcrowding. Overcrowding can lead to feed bunk competition, increased social stress, and increased demands on bedding and manure hauling. With overcrowding, there are less aggressive animals that have a much lower rate of gain, delaying their entry into the lactating herd.
Source : psu.edu