Now is the time – what to do about autumn infertility?

05-08-2008 | |
Gadd
John Gadd Topic: Pig Management

Now is the time (for those in the Northern hemisphere) to take action to combat that very common problem soon to arrive of returns, poor heats, and later on in the year, small litters, variable birthweights and probable abortion storms. Autumn infertility is as bad as ever it was.

Now is the time (for those in the Northern hemisphere) to take action to combat that very common problem soon to arrive of returns, poor heats, and later on in the year, small litters, variable birthweights and probable abortion storms. Autumn infertility is as bad as ever it was.

You’ve already noticed the evenings drawing in – but not nearly as much as your breeding females have! Their endocrine (hormone) breeding system has been programmed from thousands of years exposure to natural selection, to recognise this decreasing light pattern and make it difficult for her to conceive at this time of year.

Protective arrangement
The restraining hand of nature makes her less likely to produce a litter in late autumn and have to raise it through the harsh winter weather. The ages-old protective arrangement has by no means been bred out of our modern, sophisticated sows and gilts.

So a significant solution is to ‘fool’ the animals hormone production by artificially keeping the summer lighting going, both in intensity and duration, during the day so that she imagines that it is still summer and her breeding instinct is not dampened.

Fluorescent tubes
This is neither expensive or difficult for the indoor farmer to do by installing the correct number of fluorescent tubes (not globes and not incandescent) in front of the stalled – or group-housed – sows eyes and having them time-switched to be on for at least 16 hours in the 24, however dark it is outside.

Yes, the experts may well be right and say it is not necessarily a panacea, but my own experience is that that is does work, like as not, and because it is such a simple and not expensive precaution, surely it is worth doing anyway?

Sunburn
One other cause of autumn infertility which I have noticed especially in the hotter, sunnier parts of the world is the delayed effect of sunburn on reproduction.

Sows and gilts don’t need to be fully outdoors to get sunburnt – anyway the ‘outdoorers’ are fully aware of this likelihood and set up protective measures. But I see many group housed sows in outdoor runs/ yards which are not shaded at all – or if so, the shades are not sufficient to cover favoured siesta sites in the afternoon as the sun moves across the sky.

I’m told it only takes eight minutes exposure to set up sunburn stress which can well affect breeding capability.

Reddened backs
I also see, in the hotter, sunnier countries, an outside line of indoor stalled sows with their backs reddened due to the roof overhang not jutting forward enough. Again the solution is cheap and simple – hang some sacks down to protect from the rays.

I have some dramatic evidence to show that such unprotected sows went on to show both reduced farrowing rate and farrowing indexes compared to those further inside the building. Proof enough for me. But the farmer never sent me the next year’s results to show an improvement – but I am sure it did!



Beheer