Teagasc research shows nationally only 58% of the dairy herd calves in the first six weeks of the calving season in a calving interval of 394 days.
The Teagasc targets are 80% calved in the first six weeks and a calving interval of 365 days.
Poor trace mineral status post-calving is one of the major issues preventing cows from going back in calf within the targeted time for a compact calving window and there are significant costs associated with poor fertility and missing these targets in the national dairy herd.
1) Calving distribution
Poor herd fertility will mean a spread-out calving pattern with an average calving date slipping further every year.
Some herds will try to start calving earlier to combat this, but as a result, there may be significant feed costs, as some cows are then calving too early to match the supply of grass with the demand and others are calving too late to capitalise on early grass.
There may also be an effect on milk solids concentration as more milk is produced from grass silage.
2) Infertility treatment
Poorer fertility is associated with a greater number of straws used per calf born, increased veterinary intervention with hormone treatments and higher levels of scanning. All of these costs add up.
3) Labour
Herds with poorer fertility will have additional labour needed for heat detection, pregnancy diagnosis and repeat services.
All of these take time, resulting in increased stress for farmers as well as taking up time that could be spent on other issues on the farm.
The fatigue factor associated with a long drawn out breeding and calving season can also be very mentally challenging.
4) Replacement rate
Poorer fertility in a herd means increased replacements and it has been estimated that it costs approximately €1,500 to rear a replacement heifer including the value of the calf, labour, land and housing costs.
The value of a not in-calf cull cow at the end of lactation will vary greatly depending on the year. Overall, the cost associated with having to replace an additional 10 cows is €11,000 or €275/ha on a 40ha farm with 100 cows.
5) Milk yield per cow
Higher replacement rates in the dairy herd result in reduced herd milk yields! First, second and third lactation animals are not capable of producing the same levels as a mature cow, thus, a higher proportion of first and second lactation animals in a herd will result in reduced milk production potential.
6) The knock on effects
The year-on-year effects of poor reproductive performance can be difficult to measure, but it will have an adverse effect by reducing potential for expansion, reducing genetic gain and the inability to maintain a closed herd as more replacements are needed.
Poor trace mineral status post-calving can be one of the major issues preventing cows from getting back in calf within the targeted time for a compact-calving window (Hostetler et al., 2003).
Oral mineral nutrition is essential for the maintenance diet of cows all year round, but at critical phases of production, like pre-breeding, oral nutrition alone may not be enough for your cattle.
During the transition period, there is the major challenge of increased demand for minerals, but this time coincides with serious reductions in oral intake levels, meaning even cows on well-formulated diets can be subclinically deficient in the mineral they need for effective reproductive performance.
The issue of mineral supply is further hampered by the poor absorption of oral minerals (see table below).
Furthermore, this poor absorption can be deteriorated by antagonists. Antagonists are other trace minerals in the rumen like sulphur (S), iron (Fe) and molybdenum (Mo) that, when present in excessive amounts, bind other essential minerals, meaning cattle cannot utilise them.
All of this means oral nutrition alone might not be enough to ensure your cattle are in adequate trace mineral status to get back in calf quickly. Cows may be in subclinical mineral status where there are no clinical signs of deficiency just poor performance, like poor conception rates.
Farmers need a fast and effective way to enhance their cows mineral status in the pre-breeding window to improve herd performance and fertility.
Strategic Trace Mineral Injection could help to improve the overall pregnancy rate and calving distribution.
Years of research from leading animal health and veterinary universities from around the world have demonstrated the potential benefits of strategic mineral injections. Strategic Trace Mineral Injections are a popular way to improve herd performance in the US, Australia, South Africa and New Zealand.
Strategic Trace Mineral Injections bypass the harsh rumen environment and antagonists, rapidly raise circulating mineral levels in cows within 8-to-10 hours, and after 24 hours, the key minerals are at raised concentrations in vital storage organs like the liver (Pogge et al., 2012).
From here the minerals can be incorporated into the different body systems to help maintain immunity, fertility and support overall performance.
Pre-breeding supplementation helps to raise the trace mineral levels rapidly and effectively which could help farmers to get cows and heifers back in calf in a tighter calving pattern.
Several studies from leading US universities have researched the potential benefits of injectable trace mineral supplementation in cows in the pre-breeding period, with improvements in overall pregnancy and improved calving distribution (Mundell et al, 2012).
Ask your vet how an injectable trace mineral supplement could help get your cows back in calf.
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References:
- Teagasc Breeding Management https://www.teagasc.ie/animals/dairy/breeding–genetics/breeding-management/
- Hostetler CE, Kincaid RL, Mirando MA., Vet J. 2003 Sep;166(2):125-39. The role of essential trace elements in embryonic and fetal development in livestock.
- Nutrient Requirements of Dairy Cattle: Seventh Revised Edition, 2001
- Pogge, D. & Richter, E. Mineral concentrations of plasma and liver following injection with a trace mineral complex differ among Angus and Simmental cattle. J. Anim. Sci. 90, 2692–2698 (2012).
- Effects of prepartum and postpartum bolus injections of trace minerals on performance of beef cows and calves grazing native range 2012 L. R. Mundell, J. R. Jaeger, J. W. Waggoner, J. S. Stevenson, D. M. Grieger, L. A. Pacheco, J. W. Bolte, N. A. Aubel, G. J. Eckerle, M. J. Macek, S. M. Ensley, L. J. Havenga, and K. C. Olson
