Sammy is from a beef and sheep farm in the hills of the Rossendale valley, and although lambing time is her favourite time of year, dairy calves now generally occupy her attention for the other 50 weeks of the year! Her interest in dairy farming was sparked during a one-year work placement whilst studying for her degree, BSc Hons Animal Behaviour and Welfare, at Harper Adams University. She was based on a large dairy farm in West Sussex carrying out a research project and getting to grips with the day to day workings of the farm.
Sammy went onto work for a progressive farm animal vets practice as a Veterinary Technician after University, where she has developed a greater knowledge of the health and production aspects of dairy farming, in particular, successful calf rearing. Having seen many calf rearing systems, she has an excellent understanding of the importance of setting clear goals and getting things right from the start to ensure healthy and profitable animals.
Energy demand for any dairy animal depends on their specific requirement for; maintenance, reproduction, milk production and body reserves. Whilst our mature cows are pregnant their energy demand is focussed on maintenance and foetal growth.
As a heifer progresses through the pregnancy we must consider she is still undergoing her own continued development including her own maintenance, growth, mammary tissue growth/development, and then in the last trimester of pregnancy, the foetus goes through a huge growth phase and, therefore, energy demand increases significantly and quickly (from day 191). Some farms look to balance the diet for a heifer at 141 days (to take an average of her requirement throughout) but this is not sufficient for the third trimester as the demand for energy and protein is far greater.
The expected calf birth weight and day of gestation can be used to calculate a heifer’s requirement for metabolisable energy and protein. The risk of undersupplying energy is that the dam will prioritise the energy she has got available to the development of her calf resulting in her growth slowing or stopping altogether. This may result in difficult calving as she has not grown to the expected size.
It is important to know intakes at stages through pregnancy; pre-calving we can assume consumption to be 1.75% of body weight but this depends on the palatability of the ration put in front of them. Because heifers begin to eat lesser quantities they need the diet to be more energy-dense.
Heifers should be entering the milking parlour at 82% - 90% mature bodyweight post-calving to optimise first lactation yield (Van Amburgh et al., 1998). We can work on a relatively accurate estimation that heifers will produce the same percentage of milk of a mature cow as to what she is as a percentage of her mature weight i.e if she only enters the milking herd at 70% of mature weight, we can only expect 70% of mature cow’s milk yield from her as she is still needing a proportion of energy intake for own growth.
As with all animals, clean, fresh and plentiful water access should be available at all times and this will encourage dry matter intakes.
Feeding Seperate Diets
On some farm set-ups, it can be difficult to run two separate groups and feed two separate diets. Often it is seen as a balancing act and diets are formulated to be in the middle of mature cow and heifer requirements. The problem with this is that the diet can be of higher energy than what dry cows need and lower energy than what heifers require and, due to physical capacity, the dry cows are able to consume more. So, heifers are fed restricted protein and energy.
If we don’t account for this higher energy demand for the heifers and their need for a higher energy-dense diet, then we risk them mobilising fat from their own reserves and have high levels of NEFA’s prior to calving. Reduced dry matter intake pre-calving can lead to the same post-calving and predispose the animal to ketosis and fatty liver syndrome.
Feeding highly digestible fibre forages to help meet demand.
It is important to consider heifers are producing colostrum in the last six weeks of pregnancy and, if they are deficient in energy and protein, we cannot expect them to produce high-quality colostrum.
Focus on Calves Brochure 2021
In our 8th edition of Focus on Calves discover helpful articles from feeding to the correct use of calf jackets, written by the Wynnstay Calf & Youngstock team plus guest writers such as Anna Bowen, Nuffield Scholar.
Keep the kids busy with our front page colouring activity and don't forget to enter our exclusive competition for a chance to win a pallet of Elixir+ Calf Milk Replacer.
Reduced calving age from one year to the next may suggest improved calf and heifer rearing; however it is months later when we can make these assumptions. If a heifer is first served at 18 months old, it can be assumed that there are improvements to be made to allow future heifers to reach service weight earlier. But it is difficult at this point to then determine at which stage of rearing that this heifer didn’t meet her targets and fell behind.
Prepare yourself for summer and take a read about the different effects that parasites have on your youngstock and what can be done to reduce the risk both for internal and external parasites.
Copper and Selenium/Vitamin E are important trace elements for cattle that have a big impact on performance. Deficiencies in these elements are often exaggerated by malnutrition, poor husbandry, and ineffective parasite control.
Weighing calves on an electronic scale sounds like good practice – but who has got time for that?! I caught up with a couple of dairy farmers who have bought an electronic scale within the last 12 months to ask their thoughts so far on using it.
Don’t be fooled into thinking it is too early to begin a fly control plan in February/March! Flies have a short lifecycle (although weather dependent) and produce high numbers of eggs. By the time we begin to see the odd adult fly on the farm, we can be sure the environment has high numbers in the developing stages.
When discussing colostrum management, attention is often focused around the calf. However, to produce a quality-first feed we need to begin with the cow in her transition period. Dam colostrum contains farm-specific antibodies making it so valuable to the calves on that farm - providing protection against the pathogens, they are most likely to encounter. Diet and management of the dry cow directly influence the quality of colostrum she is able to produce.
Far too often calf rearers get caught up blaming “uncontrollable factors”, mainly the weather, for poor growth rates or poor health in their calves. But arguably, doing a better job of things that are within our control would produce a stronger calf able to deal with additional challenges.
The market is saturated with different milk powders, all with their own niche selling point and most of them promise to provide you with the solution you are looking for (whatever that may be!) I think it is fair to say many farmers look at the oil and protein levels stated on the bag, followed by price per tonne and end up making a relatively uninformed decision.
