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New research shows that cows do better indoors than outside – but does that justify mega-dairies?

Can we – should we? — rely on science and economics to tell us what is worth doing and what is not?

A new study from Nottingham University carried out for the British Society of Animal Science (briefing 1460; see the BSAS website) by J M Wilkinson, P C Garnsworthy and J N Huxley tells us that “High-quality pasture alone does not provide balanced diets for maximum feed efficiency – continuous housing presents an opportunity to realize a cow’s full potential … Larger herds also allow cows to be grouped so their needs can be more easily met. There is concern that continuous housing means normal behaviour is compromised but grazing can also deprive the animal of shade and create periods of hunger, discomfort and stress in hot, dry weather”.

The slightly longer version also tells us that cows given access only to grass typically yield 4000-5000 litres per year, while those fed mainly on grass with some time indoors reach 6000-8000 litres; but those fed continuously indoors on a very high plane of nutrition reach 10,000-plus. That is, they reach their “full genetic potential”. However, we are told, “Plans to establish large, continuously housed dairy units in the UK have attracted much media attention and opposition from lobby groups”.

The message is clear. Keeping cows in very large herds indoors and feeding them on a high-energy high-protein diet produces more milk per cow, and so must be more “efficient”, and it doesn’t do the cows any harm – in fact it protects them from the heat and glare of the sun, so they are better off. The only opposition comes from the “media” (who of course are up to mischief) and “lobby groups” (who of course have bees in their bonnets and are generally muddle-headed).

Yet some of the strongest opposition comes from scientists and from cattle farmers, some of them fifth generation, many of them with agricultural degrees and experience of farming worldwide. One reason these expert detractors are not widely known and heard is that, alas, most people in Britain these days are strictly urban and take little or no interest in agriculture, and media coverage is correspondingly sparse and erratic. The thoughts of the detractors, however expert,  do not routinely get published in academic journals because most of them are not academics – and if they wanted to be, they would find it very difficult, going on impossible, to get funding, precisely because they are not dancing to the corporate tune.

Some of the points raised by the informed detractors are as follows:


Constantly we are told that large farm units of any kind are more “efficient” – but of course, it all depends on how we define efficiency. In money terms, given the present state of the economy, large units are efficient. After all, oil is still cheap – or at least it’s cheaper and less trouble than labour; corporates get tax breaks; and the inputs and the collateral damage are not properly costed and sometimes not costed at all. The largely unexamined assumption behind the whole modern economy, too, is that whatever is profitable must be good – since, the myth has it, the market economy ensures that only good things can be profitable.

But if we measure efficiency in any terms other than short-term profit, then mega-units – and particularly mega-cattle units – look very different indeed.

Thus, while a cow in a state of nature has a life expectancy of 12 to 25 years, and a 4000-litre per year cow in a traditional herd may give 10 lactations or more, 10,000 litre cows in the national herd average fewer than three lactations, and are slaughtered at five to six years of age. This means that 40% of the cow’s life is non-productive.

Then again, the 10,000-litre cow doesn’t produce all that milk from thin air. It takes 0.45KG of concentrate* at 18% protein to produce 1 litre of milk at 3% protein. That’s 400 grams of protein consumed for every 30 grams produced – a conversion ratio of 13 to 1. The concentrate includes wheat, soya and other pulses and so on — all of which could be consumed by humans. Thus cows raised on concentrate, unlike those raised on pasture, compete with us for food.

Energy and the Biosphere

Indoor systems require huge inputs of energy that are not needed for animals raised on grass. The concentrate feeds are raised with the aid of oil-based fertilizers, herbicides, and pesticides. Then there’s the energy costs of ploughing and transport; and of creating and maintaining the infrastructure, including roads, machinery and storage facilities.

Very important too though rarely mentioned is that large dairy farms tend to be based upon the “flying herd” system, where only milking cows are kept on the farm – replacements are raised elsewhere and then shipped in on the point of calving or just having calved (both of which are fairly stressful for cows). For every “efficient” mega dairy, there is another farm somewhere doing nothing but raising fresh replacements – output in terms of milk is nil. Also, in 2001/2002, we were faced with Foot & Mouth Disease – which spread as fast and far as it did largely because with the present system animals and therefore disease must be moved great distances, and rapidly, about the country. We were slaughtering whole herds on the basis of a single confirmed case, and shut down any contiguous premises. If the same approach remains in place (and things didn’t change between 1960s and 2002), then the prospect of culling a herd of 8000 cows (Nocton) or more seems to be something “sustainable intensification” seems to have conveniently ignored.

On the global front, some studies suggest that well-managed grassland is at least carbon-neutral. The cattle produce a lot of methane, but grass (when appropriately grazed) serves nonetheless as a net carbon sink. This is far from established – but again, this finding is potentially so important that it ought to be followed up with all possible urgency. Instead we are simply told as a matter of dogma that cattle on grass produce more greenhouse gases per head than cattle raised indoors. The enormous carbon-cost of raising cereal and soya to feed the cattle indoors, is of course not taken into account.

Welfare in general 

Advocates of mega-units like to tell us that the animals are better off because big outfits can afford in-house vets. But then – they need them. Big high-tech units are very high capital and so they require the animals to many times more productive than is natural to them. A grass-fed Shorthorn (say) producing 4000 litres of milk on grass is somewhat more than twice as productive as a wild cow. A continuously housed Holstein producing 12,000 litres (almost modest by today’s standards) as at least six times more productive than a wild cow. The physiological strain is huge. More generally: cows, being ruminants, are anatomically and physiologically adjusted to a high-bulk, low-energy, low-protein diet. The artificially-enriched diets that enable them to reach their “full genetic potential” are a huge physiological insult – and the resulting morbidity, unsurprisingly, is enormous. Cattle on well-managed semi-wild pasture typically need hardly any veterinary attention at all.

Shade in particular 

It is of course true that animals indoors are sheltered from the glare of the sun. It’s true, too, that cattle like shade. All animals like shade (unless, like lizards in the early morning, they sun-bathe to warm themselves up). Even zebras and wildebeest, which spend their days on the plains of Africa, seek shade when they can get it (I have seen them in San Diego Wildlife Park standing in long lines in the shadow of a single telegraph pole). European cattle are descended from the aurochs – an animal of open woodland. In fact, cattle in general are basically forest animals. The only apparent exception I can think of is the yak, The North American bison is commonly shown on open prairie but it is a recent descendant of the Wood Bison of Europe (of which there are still some in Poland) – and they like woodland too. 

So indeed: cattle in open meadows on hot days are not well served. But the answer to this surely lies in some version of agroforestry. (Milk yield in Costa Rica has been shown to increase by up to 30 per cent when the animals are raised in woods).

Milk quality 

Many studies suggest that the fatty acid profile of milk from pasture-fed animals – and especially the proportion of omega-3 polyunsaturates – is very different from that of continuously-housed animals on a high-nutrient diet. If confirmed, this has huge implications for human health. Yet it is hard to find any adequately funded studies to explore this. After all, the results might not favour the high-tech dairy industry.

A matter of paradigm 

In truth, the people with the most power in agriculture are those who believe, as a matter of dogma, that farming should be treated as “a business like any other” and that business should be defined simply as the means by which wealth is maximized. People who believe this are more likely to achieve positions of influence precisely because those who focus on money are most likely to make a lot of it – and money in a society like ours, where no other rules apply, is power. Politics these days serves big industry and big banks; and so does academe.

This latest Nottingham paper makes perfect sense if we are content to dwell within the prevailing economic paradigm – if we are indeed content to accept that short-term money is all that counts. But this, surely, is high on a shortlist of ideas that threatens to kill us all.  

Footnote: On his excellent website,, Graham Harvey now draws attention to a new mega-dairy planned for Vietnam – intended to hold 67,000 cows. Grotesque. But it’s the kind of enterprise that modern governments and big business, the powers that be, apparently believe is the way forward. People who actually know something and give a damn can’t let this go on.