The Feeding Herd – ‘Hidden’ Costs

NADIS is a network of 40 veterinary practices and six veterinary colleges monitoring diseases in cattle sheep and pigs in the UK.

NADIS data can highlight potential livestock disease and parasite incidence before they peak, providing a valuable early warning for the month ahead.

NADIS disease bulletins are written specifically for farmers, to increase awareness of prevalent conditions and promote disease prevention and control, in order to benefit animal health and welfare. Farmers are advised to discuss their individual farm circumstances with their veterinary surgeon.

January 2004

By Mark White BVSc DPM MRCVS


NADIS Pig Disease Focus

The Feeding Herd – “Hidden” Costs

Lack of recording in the breeding herd has been previously highlighted as a fault of many pig farms currently in that problems – particularly of fertility and production -cannot be properly investigated without them. 

As a general finding, record keeping in the feeding herd is even more sparse on most herds. 

Accurate growth data is costly – in terms of time – to generate; feed efficiency data is usually only accurate on a herd basis if measured over a prolonged period of time (e.g. 6 months) and, therefore, gives little indication of variations or efficiency of feed usage in any particular age group. For most farms, the measure of feeding herd efficiency is the mortality rate and abattoir returns giving weight and grade data.

Mortality is easily measured but where disease occurs that increases mortality, the cost of lost growth/poor feed efficiency is often much higher. As an example, an outbreak of Swine Dysentery may increase mortality by 5% in growing/finishing pigs costing £3000/1000 pigs affected. 

However, feed efficiency will decline by 0.5 or more, more than doubling this cost.  Slowed growth may lead to reduced finishing weight (if space is fully utilised) with further cost penalty.

However, there is another cost associated with disease that producers do have data for but frequently fail to make full use of. That is the issue of condemnation at slaughter. A full carcass condemnation equates to an on farm death with a premium as a result of transport costs and inflated disposal costs at the abattoir.

Condemnation rates from farms vary considerably. Many will average below 0.02% i.e. less than 1.5kg on a consignment of 100 bacon pigs. In others, it has been reported to be as high as 1% equivalent to one whole carcass per batch (These figures ignore condemnation of offal, which do not contribute to the payment). 

The common areas of condemnation are part legs (anything from 2-20kg), skin (6kg), head (6kg), chest wall (10kg) and whole carcass (70kg).

The main ailments that occur on farm which are associated with carcass condemnation are:

  • Erysipelas causing skin and leg rejection.

  • Tail biting causing multiple abscessation throughout the body and leading to whole carcass rejection (usually listed by meat inspectors as Pyaemia).

  • Septic pleurisy and pneumonia causing chest or whole carcass condemnation – usually resulting from complex bacterial infection including Glassers Disease, Pasteurella etc …

  • TB lesions in head lymph nodes (leading to head condemnation).

  • Injuries to lower limbs leading to trimming.

An interesting observation from one large unit which sold pigs to 2 separate outlets was the difference in condemnation rates. With pigs allocated to the 2 outlets on a random basis, measured over a year, the condemnation rates from 1 outlet was 3 times that of the other.

A final element of loss that producers rarely take note of is killing out percentage, which, again, can be highly variable. 

The above unit mentioned also measured a difference of 0.7% killing out percentage over a year between the 2 abattoirs – rather bafflingly the higher yield being produced from pigs travelling the greater distance. In this case, the higher yield came from the abattoir with the higher condemnation rate acting as something of a counter-balance.

The point of these notes it to highlight that there is a rich source of usable data available for the feeding herd, which is frequently ignored. Killing out percentage can have a dramatic influence on returns (yields ranging from 73% – 76% for a 70kg carcass are reported) and, only if such information is collated, can it be used to improve output from the farm.

While every effort is made to ensure that the content of this forecast is accurate at the time of publication, NADIS cannot accept responsibility for errors or omissions. All information is general and will need to be adapted in the light of individual farm circumstances in consultation with your veterinary surgeon

Copyright © NADIS 2002


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