Cows transition through several phases during their production cycle. This month, Wihan Kitshoff, ruminant technical advisor at Meadow Feeds, takes Food For Mzansi readers through each phase and the required nutrition that goes with it.
Kitshoff explains that transition cows are defined as cows going through the “steam-up” period, the calving, and the period of lactation. He says that cows undergo several physiological and metabolic changes during these periods and that together, these last about 46 days.
“When a cow is pregnant, nutrients are needed for the maintenance and growth of the uterus, the foetus, the foetal fluids, the placenta, and the uterine tissue, as well as other development. All these factors must be given proper attention and the different nutritional requirements must be met with a different ration she receives.”
Steam-up is the period the cows go through from 21 days before they calve. This also forms part of the cow’s “dry period”, which is when they are not producing milk. Kitshoff says after lactation, the cow dries up and it takes about 25 to 30 days for the mammary cells in the cow’s udder to renew.
“Also, the rumen microbial population must migrate from an energy-dense lactation diet that was fed to the cow during lactation, to a low-density diet typically higher in fibre in the dry period. This requires 14 to 21 days for the rumen to properly adjust, and usually ends when the rumen microbes must adapt once again around three weeks before calving.”
Cows have four compartments in their stomachs with the rumen being one of them. The microbes in the cow’s rumen break down the proteins in the cow’s diet and convert them to amino acids, then ammonia.
When the transition cow goes through these different phases, the microbes in their rumen must adapt to the variations in their diet. Cows are usually given a diet with less energy after lactation, which is then adjusted again during the steam-up period.
Beware of infection
During the dry period, says Kitshoff, cows are more susceptible to infection. He says pressure builds up in the udder in preparation for milk production but does not yet get evacuated. “This causes leakage from quarters, allowing bacteria to penetrate the teat canal, and cause infection such as mastitis.”
This is why, he explains, managing your transition cows correctly is just as important as feeding them correctly. For cows to have optimised production, they also need to be comfortable.
“We could have the best-formulated diet with the best ingredients, but if cows do not have access to it, the diet composition would be irrelevant. In growing herds, overcrowding during this critical phase can be a major challenge to cows. Thus, one of the main objectives during this period is not to only focus on diet composition, but also on cow comfort to maximise dry matter intake.”
Calving and fresh cow phases
During the last five days before calving, cows experience a huge dip in appetite. Kitshoff says the biggest challenge during this phase is to get the cow to eat as soon as possible after calving.
He explains that during the fresh cow phase, which is from the time of birth to 21 days after calving, cows will need to have their food intake increased urgently as they need more energy. Their movement also needs to be managed to minimise their stress.
“[A practice] that can increase dry matter intake and modulate stress is keeping the number of pen movements at the smallest minimum possible to decrease the stress associated with the reestablishment of pen social hierarchy. “
Kitshoff also explains that cows who had difficult calving have a higher risk of developing diseases when compared to the cows who gave normal birth.
That’s why calving cows need to be monitored so that any difficulties can be identified early and treated urgently, he adds.
“That’s the main objective in the fresh period if you supply the cow with immediate nutrition while being in a negative energy balance but still maximising milk yield for her following lactation.”
Importance of proper feeding
The fresh cow phase, says Kitshoff, is the phase where cows are most vulnerable as their metabolic needs increase dramatically.
He explains that the cow’s milk production is directly related to the feed she receives during the fresh cow phase.
He also says that cows are vulnerable to several diseases during this transition, including mastitis and milk fever.
“The impact of the health problems can be drastically limited by the correct feeding and management of the transition cow. Such management also reduces stress and the energy cost of an activated immune response when these challenges occur.”
Kitshoff recommends that dairy cow farmers do the following to ensure optimal health and production in their transition cows:
- Limit the energy intake of the dry cows so it is sufficient just for maintenance, and to prevent overly fat cows.
- Feed anionic salts to the steam-up cow to limit the incidents of milk fever.
- Increase the nutrient concentration when the cow’s dry matter intake decreases right before they calve.
- Use the same feed ingredients or raw materials that you will use when the cow is lactating. The ration included during the steam-up ration supports smooth rumen microbe adaption to the lactation diet.
- Gradually increase starch content in the ration from dry cow to lactating cow.
For the best nutrition of your pre-calving cows, Meadow Feeds has formulated Dry Cow Plus 20, which contains high levels of protein, fibre, calcium, anionic salts and phosphorus. The feed acts as a prophylactic against milk fever and is meant for cows in the steam up phase.
The Meadow Feeds Post Calving range contains multiple products meant for optimum lactation, products like Pastural 12, which has very high levels of starch and protected fat needed for pasture farming. The feed contains Rumensin, Acidbuf, and Magnesium Oxide.
To summarise, Kitshoff says farmers need to keep their transitioning cows separate from the rest of the herd. He says that this is crucial for a healthy, successful operation.
“In my opinion, management of transition cows is one of the most important aspects of farm management and will set up dairy cows for success during the lactation. The main goal of these practices must be maximising dry matter intake and modulating stress and inflammation.”
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