Correct nutrition and health planning can help counter the rise in leg health issues seen by producers of heavy birds such as turkeys, suggest specialist poultry vets and nutritionists.
Speaking at a recent seminar on turkey leg health, Keith Warner of Herefordshire’s Minster Vets said that nutrition from the feeding of parent stock to the finished bird had to be right: “We need to make sure infant birds have a good start.
“Imbalance in nutrition is often linked to a gut health issue. For young, fast-growing birds, this can lead to weaknesses in joints and bones that the bird simply cannot remodel quickly enough to correct realignment as it puts on more weight,” he told producers at the seminar in Knutsford staged by HST Feeds.
Of all the skeleton, it was the leg bones that were under most stress during the bird’s growth cycle, he said. This could lead to deformities such as cowboy stance, crooked toe and ruptured tendons.
“None of these conditions in isolation is fully understood, but they are linked to rapid growth and weight gain. What we do know is they all show a response when vitamin D3 is supplemented in the diet.”
Ian Mackinson, HST Feeds’ poultry nutritionist, explained that vitamin D3 was vital in helping mobilise calcium within the body. “About 97% of calcium in a bird is found in the skeleton. If a deficiency arises, it’s commonly seen as rickets or leg problems in poultry.”
A poultry diet needed to achieve a 2:1 ratio of calcium and phosphorus, particularly in young birds: “Too much calcium and the birds get rid of an excess in the form of calcium phosphate, leading to a shortage of phosphorus,” he explained.
Other vitamins such as C, A, E, and B6 were also needed, along with trace elements of zinc and manganese. “Even when fed in balance, a period of stress, such as moving or mixing or birds, can lead to deficiencies affecting growth and health,” warned Mr Mackinson.
Nutrition alone could not protect birds, however. A planned health strategy was important for year-round and seasonal producers, said Mr Warner. A raft of mycoplasma bacteria in poultry housing could cause lameness and respiratory disease – with treatment often resulting in only temporary improvements – highlighting the need for good hygiene.
The bacterial respiratory disease ORT was usually present in birds, but did not necessarily result in poor health unless combined with the more worrying viral disease ART, explained Mr Warner. “This can allow ORT to become pathogenic leading to heavy losses, as seen several years ago in stags from 8-14 weeks old.
“Early signs include coughs and loss of appetite among birds. You must consult your vet on appropriate action including vaccination. Key, as with many diseases, is to avoid stresses such as mixing birds or chilling birds (due to inadequate heat during night-time),” added Mr Warner.
Health plans had to be backed up by good biosecurity, suggested David Neilson of Cranberry Foods, which rears 3.8m turkeys annually. “It’s often seen as old hat, but biosecurity needs to be up to date. Investing in biosecurity is investing in your flock,” he said.
With the expansion of free-range units nationwide, infection risks were higher now than ever, he suggested. Even essential visitors to units, such as vets, had to be treated as potential vectors.
“Gate-off your rearing sheds, have boot wash and changing stations, remove waste including dead birds immediately and store bedding securely to reduce risks of contamination.”