Timely calving – to have first-calf heifers enter the milking string at 22 to 24 months old – is not a stand-alone decision.

It’s not like producers wake up one day and say, “I think I’ll breed my heifers once they hit 12 months old.” This decision needs to take a number of factors into account to capitalize on production efficiencies to have replacement heifers “breeding rod ready” at 12 months old.

This goal will only be achieved utilizing a total package encompassing nutrition, preventative medicine and management strategies.

Proactive decisions in these three areas will influence the productivity and lifetime profitability of dairy replacement heifers.

Dry cow nutrition and transitional ration management are the first areas of concern. You have heard the expression, “You are what you eat.” For the newborn calf, the reality is: “You are what your mother ate.”

Adequate body condition at dryoff plus correct amounts of protein, energy, vitamins, macrominerals and trace minerals will contribute to a healthy fetus.

Profit-robbing blood suckers – not the government but internal and external parasites, should also be controlled at this time. This will benefit not only the cow, resulting in greater productivity, but also minimize the spread of parasites to newborns.

Even moderately parasitized youngstock fail to thrive, fail to reach proper breeding size/weight on time and have lower lifetime profitability. Vaccination against diseases specific to your region, i.e.: IBR, BVD, PI3, BRSV, E. coli and Leptospirosis will ensure quality colostrum for the newborn calf.

Consider establishing a colostrum bank with surplus colostrum from healthy, disease-free, leucosis-negative older cows to have on hand for emergencies or to supplement calves born to first-calf heifers.

Management of the newborn includes colostrum intake, navel disinfection and Vitamin A/D, Vitamin E/selenium supplementation if a deficiency exists in your area.

If neonatal gastrointestinal viruses such as Coronavirus and Rotavirus are an issue in your herd, an oral vaccination can be given to calves at birth. Consult your veterinarian for further information. Some veterinarians report that calves that are sluggish at birth experience benefit from an injection of Meloxicam.

Calf feeding strategies are crucial. The most efficient gains are made in the first year of life. Years ago, the rule of thumb was to feed calves 4 litres of milk a day until weaning.

Current practice recommends 6 litres a day for newborns, increasing to 10 litres or more by 6 weeks old. This may require more than two-times-a-day feeding to prevent nutritional scours. The extra calories not only provide protein and energy for growth but also strengthen the immune system.

Higher protein levels, either through whole milk or high-protein milk replacer plus a high-protein calf starter (minimum 24 percent protein), will produce taller, leaner animals. Once calves are weaned, they need to continue on quality, higher-protein feeds.

Calves fed on this regime usually double their weight by 60 days and reach withers height of 52 inches by 12 to 13 months old. A dedicated heifer facility where heifers are grouped by size minimizes overcrowding and competition.

Care and attention is required so these valuable replacements don’t end up being out of sight, out of mind and out of feed.

Parasite control is also important in the growing heifer. Calves that appear unthrifty may be harbouring protozoa such as Coccidia.

Untreated protozoal infections can interfere with nutrient absorption, resulting in sporadic diarrhea. Upon diagnosis based on fecal sample, treat and follow by using a preventive coccidiostat in heifer-growing rations.

At 4 months old, heifer calves can be vaccinated. Consult your veterinarian for a protocol to protect against diseases endemic to your area.

Maximum growth is only achieved by proper nutrition and control of clinical and subclinical disease. A top-quality heifer-rearing program is essential for lifetime reproductive success.

Nutrition and growth of the young heifer is a determinant of lifetime reproduction influencing both oocyte quality and ovarian function.

Genetics plays a large role in successful heifer outcome. We need to be selecting for lifetime production and choosing animals with high milk LPI and strong health traits.

The proactive decisions we have made should result in most heifers cycling by 9 to 10 months old. There are a variety of strategies producers can use at this stage.

Many producers are utilizing genomic testing to identify genetically superior animals. Elite heifers can be superovulated and flushed at 10.5 to 11.5 months old with embryos implanted to other lower GLPI heifers. Heifers failing to conceive after two embryo implant cycles can be bred and still calve at 24 to 25 months.

Some producers are breeding all of their heifers using sexed semen. This usually results in a smaller calf and fewer calving difficulties.

After two or three unsuccessful breeding attempts using sexed semen, some producers will then use a high-fertility, easy-calving sire.

Heifers remaining open after six services often pursue careers in the food industry. Examining heifers for pregnancy is an important part of the herd reproductive control program. Early identification of open animals gives these animals a better chance to be re-bred before getting too old.

For the last trimester of pregnancy, it is important to treat the heifer as we would a transition cow. It is crucial that she calve with adequate body condition to sustain milk production but not with excess condition that can lead to calving difficulties.

The goal is to calve the heifer with minimal trauma and look after her special needs in the immediate after-calving period. If a heifer has been in labour for several hours, she needs to be examined to determine if the calf is in the correct position or if there is a malpresentation.

Experience will tell you when to assist the delivery, when to use the calf puller or when to call for caesarian section. Wash the vulvar area of the heifer and use plastic disposable gloves for examination to prevent introduction of pathogens into the uterus.

Use calving chains that can be disinfected rather than baler twine. In the event of a difficult birth, try to minimize the swelling in the vagina after delivery. A rectal sleeve filled with ice placed and held inside the vagina can prevent swelling of the perivaginal tissue.

Recent research suggests that the product previously mentioned, Meloxicam, can be given subcutaneously to fresh heifers to assist in the after-calving period.

This drug blocks Prostaglandin E (the pain pathway) without blocking Prostaglandin F (which assists uterine involution). Researchers suggest that these heifers feel better, eat better and develop fewer cases of ketosis and displaced abomasum. Consult your veterinarian for more information.

Again, attention to detail is paramount. One of my producers has a very profitable revenue stream selling his surplus heifers to neighbours who calve their heifers out at 22 to 24 months old but have failed to put the strategies in place to not only calve animals at this age but also get them back in calf.

A high percentage of “failed heifers,” heifers that fail to remain in the herd for second and subsequent lactations, indicates problems somewhere along the timeline.

A collaborative effort by the nutritionist/feed adviser, your veterinarian and your reproductive/genetics consultant, coordinated by the producer, can move you on the path of profitability.  PD

PHOTO
Reaching the goal of heifers entering the milking string at 22 to 24 months old starts even before the heifer is born. Photo courtesy of The Semex Alliance.