This winter has generally been extremely wet and mild, which can cause tremendous problems for free-range chickens. Richard Turner explains how to minimise stress and diseases.
Cold, sunny and dry weather is ideal for reducing the disease burden on poultry ranges. So it’s hardly surprising that this year’s winter has been extremely challenging for free-range poultry producers. Faced with muddy pasture and wet litter, diseases and parasites are in plentiful supply.To overcome these difficulties, farmers should aim to maximise their birds’ intestinal health. If the gut is functioning well, the birds can better absorb energy and protein, thereby maximising production and the immune system.
Most gut problems happen at times of stress – when pullets arrive on farm or reach peak lay, for example. Signs include frothy yellow droppings, reduced feed and water intake, slow weight gain and small eggs with poor shell quality. To minimise such stress, producers should reduce potential disease challenges through careful terminal cleaning and range management.
That may be easier said than done in a season like this. The key to good range management is drainage, as standing water can harbour bacteria that can cause diarrhoea. Producers should use French drains and areas of hard standing around the house, and rotate paddocks if possible to give the pasture a break.
Sunlight is nature’s aid in eliminating bacteria, viruses and parasites, so it helps to keep grass short and trees trimmed to maximise the light reaching the soil’s surface. It’s also worth applying agricultural lime at turnaround to help destroy worm eggs and other pathogens.
The main worms to look out for are Ascaridia, Capillaria and Heterakis. Ascaridia and Capillaria can irritate the gut lining, reducing nutrient absorption and causing diarrhoea. Although Heterakis are not harmful in their own right they can carry blackhead, which is potentially fatal to chickens. Worm burdens can also depress appetite, knocking the balance of good and bad bacteria in the intestine.
We recommend that producers take faecal egg counts every six to eight weeks, and use a licensed wormer if required, paying particular attention to dose rates to reduce the danger of anthelmintic resistance building up. It’s also important to use an approved disinfectant at cleanout, as not all disinfectants will destroy worm eggs.
Another consideration when it comes to gut health is drinking water. If you’re using borehole water it’s vital to have a water treatment system that is regularly serviced. Even with mains water bacteria can build up, so use a stabilised hydrogen peroxide-based sanitiser to help destroy biofilm, and flush drinker lines weekly to clear out potentially stagnant water. Farmers should also monitor the mineral content of their water, as high levels of certain minerals can irritate the intestine.
To bolster the birds’ gut health and immunity, producers should consider using feed or water additives at times of stress or throughout lay. Probiotics can be given to increase the population of ‘good’ bacteria in the intestine and out-compete ‘bad’ bacteria.
Protected organic acids, which make the gut more acidic, will encourage the ‘good’ bacteria, while discouraging harmful bacteria. They also help in the development of villi in the gut, which directly boosts nutrient absorption and improves performance.
Mannan Oligosaccharides can also be beneficial, binding to the surface of harmful bacteria and preventing them from attaching to the gut, so they are harmlessly excreted.
As any poultry producer knows, keeping free-range birds healthy and productive in a winter like this is not an easy task. However, close attention to detail, with optimal hygiene and the support of dietary supplements, will prove beneficial in the long run.