Growth boosted by more insulation and better airflow

14 November 1997

Growth boosted by more insulation and better airflow

By Jonathan Riley

INVESTMENTS in housing and changes to management practice have improved growth rates by 20%, and cut finishing times by 16 days, at MLCs Stotfold Pig Development Unit, Stotfold, Herts.

Unit manager Paul Blanchard says ventilation systems, some dating back to the 1960s, needed replacing.

Styrofoam insulation panels in the accommodation had shrunk over the years, creating gaps for cold air to enter, interrupting airflow and lowering temperatures.

Fans triggered by rising temperature were, therefore, not operating as early as they should, reducing airflow and compounding difficulties with blue ear and respiratory disease.

Lung lesion scores, on a scale of 1 to 55, were higher than acceptable at 9.8, while snout scores were 1.46 on a five-point scale. Both are vital indicators of respiratory disease, says Dr Blanchard.

About £20,000 was invested in the flat-decks which included laminated polystyrene sheets fitted to improve insulation. Any protrusions on the ceiling were removed to improve airflow without draughts. New fans and larger inlets were installed, to increase ventilation capacity by 50% in the flat-decks and 200% in the grower/finisher accommodation.

A more sensitive control system was then added to minimise variations in environmental conditions.

"These changes have helped cut lung lesion scores by 75% to 2.4, while snout scores have halved."

Growth rates in flat-decks have improved from 394g a day before refurbishment to 489g a day, and from 750g a day to up to 985g a day in grower/finisher housing.

"Health and performance have also improved because we used the conversion time to make management changes," he says.

"We decided on a partial depopulation and sold all the piglets from the farrowing house at about 7.5kg. This gave us a five-week break in production to carry out refurbishment and to introduce a strict all-in, all-out policy.

Side-streaming of poorer pigs from weaning was also carried out. "Streamed pigs account for about 6% of weaners and the policy of removal is strictly applied, with any pigs taken out never returned to the main pig flow," he says.

Instead, those that are small or sickly are taken out of the production line and put into Nurtinger units or a hospital pen, making labour use more efficient because the group can be handled and treated together. And these pigs face less competition at feeding, allowing them to recover faster.

The feeding regime can be tailored to the poorer pigs needs and a higher quality diet can be fed.

"Equally, when sick pigs and slower growing pigs are removed from the main production group, management becomes easier and costs can be cut," says Dr Blanchard. That is because the variation within a pen is smaller and diet quality can be matched to the growth stage of pigs more accurately. In addition, room temperatures and ventilation rates can be set for healthy pigs.

"This means cheaper, lower protein diets can be introduced sooner because we are not having to cater for the poorer pigs higher nutrient requirement."

For example, feed costs in flat-decks have fallen by 15.7p/kg liveweight or £1 a pig.

"In the finisher herd where still cheaper rations can be offered, feed conversion ratios have improved from 2.58 to 2.1 and savings of 7.8p/kg liveweight gain or £5.55 a pig have been made," he says.


&#8226 Improved insulation and airflow.

&#8226 Side-streaming of poorer pigs.

&#8226 Improved growth rates.

New insulation panels at MLCs Stotfold unit have improved airflow, and so reduced disease.

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