As part of my Nuffield Farming Scholarship I have been researching my topic: ‘Increasing Rumen Nitrogen Efficiency in UK Dairy Production’. But are there other ways to improve overall feed efficiency? This blog follows my thoughts as I visited some key North American dairy units.
In the UK we have a vast range of different breeds and genetics in our dairy herds, ranging from the high producing 700-800kg Holstein to the 450-500kg Kiwi crossbred grazing cow. However, we must make sure we have the correct cow for the system. We have a strong North American Holstein influence in our UK herds, yet our diets do not reflect those of the states, relying on grazed grass and grass silage to make up a significant proportion of the diet. This therefore begs the question – do we have the correct cow in the UK?
During my time in Green Bay, Wisconsin, I visited a 6,000 cow herd milking crossbreds on an all year round indoor system. The herd had the influence of 2/3 Holstein genetics and 1/3 US jersey genetics. Here I found two herds differing genetically and producing similar yield at very different efficiency rates (see Table 1). The crossbred herd achieved lower yields, but equal MS output from 2.5kg less DM/cow.
Comparison of Crossbred and Holstein herd production outputs
|Milk Butterfat (%)||4.2||3.6|
|Milk Protein (%)||3.4||3.1|
|Milk Solids (kg/day)||2.9||2.9|
With demand for higher milk solids in the UK dairy industry, could crossbreeding present a viable option to produce a more efficient cow? Rearing a smaller cow with a lower maintenance cost, producing higher kg’s of milk solids whilst eating less dry matter. This in return would reduce manure excretion which will be proactive against environmental issues we may face in the future, whilst also meeting the processors demands of higher milk solids meaning they are carrying less water around the country.
Sticking with the crossbreeding theme, I also took the opportunity to visit Leachman Cattle Company of Colorado – a company built by Lee Leachman that has developed and bred the Stabiliser breed. The company markets over 1,500 bulls/yr, using their own $Profit figures to sell the bulls on their projected progeny performance. The bulls are bred for feed efficiency (DM to kg/LWG), with this equating to the associated $Profit figures.
Can the dairy industry learn something from this through producing a composite breed that can retain highbred vigour and increase feed efficiency?
Rearing to improve environmental efficiency
From six months until calving, a dairy heifer is very inefficient at converting her feed into live weight, along with nitrogen to body weight. During this period, heifers can eat up to 4t of dry matter and produce a great deal of manure, with little return for the farmer. It is essential to make this period as concise as possible through targeting higher growth rates and 21-24 months for the first calving.
In summary, my travels have raised the question as to whether we have the right cow for our system here in the UK? In short, there is no point keeping a heavy Holstein cow on a UK system using a diet with a high proportion of grazed grass or grass silage. Experimenting with breeds with aim to reduce cow size whilst maintain milk solids production is key. My travels in the states showed me that it really is possible to achieve a high yielding crossbred herd, but we must remember that efficiency ultimately starts with young stock management.
My next blog will discuss my findings from my travels to the Netherlands, looking at their silage practices and environmental restrictions.