Richard Jackson, Clinical Director
Over the last few months, we have had one of the hottest summers on record. Whilst many of us are very aware of the immediate impact of this on our birds in terms of risk of mortality and reductions in egg production and growth, there are longer term effects to consider.
During hot weather, birds divert blood from their intestines to their skin to help lose heat, and additionally the birds eat less feed, which changes the pH of the gut. These two changes increase inflammation and increase the size of the junctions between the cells lining the gut leading to increased gut leakage. Furthermore, this reduction in blood flow to the gut makes it harder for the gut to produce its own antioxidants.
This damage to the intestinal lining can reduce the absorption of nutrients (leading to poorer growth or egg production), diarrhoea (the unabsorbed nutrients travels to the caeca and feed harmful bacteria which then travel from the caeca (where they are meant to remain) up into the small intestine to cause enteritis and changing the bacterial populations in the gut. Several studies have shown that even when the hot weather subsides the changes to the intestinal bacterial populations remain for quite some time.
The increased permeability of the gut can allow bacteria such as E. coli to leak into the blood stream to cause lameness, peritonitis and/or septicaemia.
It is therefore important that after birds have been exposed to heat stress, we try to help restore the normal intestinal bacterial populations.
Probiotics such as Biacton (Lactobacillus) can be given to help bolster the populations of beneficial bacteria in the gut and outcompete the harmful species.
Buffered organic acids such as ABC pH or ABC Start can be given (ideally in combination with probiotics) to help encourage the proliferation of beneficial bacteria and help discourage the proliferation of harmful bacteria. Organic acids act as a feed source for beneficial bacteria. Note it is important to use buffered organic acids (cheaper organic acid blends after generally not buffered) as unbuffered acids dissociate before they reach the gut and therefore aren’t useful.
Specific essential oils can help with recovery of the gut after heat stress associated damage.
There is also the potential for ABC Support to be given in feed which is a blend of essential oils designed to aid the intestine recovery after heat stress, therefore helping to maintain good gut health.
If you are interested in exploring the use of essential oils and in-feed nutraceuticals, please discuss this with your St David’s vet and we can advise you on the best route forward.
If you would like further information generally, please contact your local St David’s vet.