Dr Kenny Nutting BVetMed MRCVS
For once, the harvests are ahead of schedule and this has allowed, in most circumstances, the slightly earlier release of partridges. There is always the next reason as to why someone cannot take the birds and this year it has been poor cover crop growth. The sites that have or are mid-release of partridge have shown relatively little disease issues. With the strong summer weather partridges have reared extremely well and in doing so have ideal body weight to take on any small challenge faced during the transfer from rearing site to release/holding pen. The majority of shoots under our care have now adopted the use of Ultimate Acid for the first 2 weeks of release for both partridges and pheasants. With sites that are likely to be under greater than normal levels of stress, I have also been advising the use of Coccilin Plus alongside the acid. This adds another layer of bacterial control and allows the intestinal immune system to fight off other diseases such as Hexamita.
Interestingly, in years gone by, we have tended to treat heavily for reoccurring high levels of Hexamita on rearing sites in partridges. I have several partridge rearing sites where the levels of stress on the birds are relatively low and if the weather holds, we do not treat the high levels of Hexamita seen but maintain good gut health on the Ultimate Acid and Cocillin Plus combination. This has allowed for just one treatment at point of release to reduce the levels of Hexamita present so that they do not take advantage of partridge during this stressful period.
With the good weather about, there seems to have been periods of excitement and the trialling of new release methods for both partridge and pheasants. This year I have seen 10,000 pheasants released into an open valley with only one line of fencing at the bottom of the valley to stop excess wandering. The birds here were released in 10ft by 10ft pens and after 24 hours these were opened out and the birds remained within the steep valley sides for at least 2 weeks. By this time they had adapted to their new surroundings and were happy to go home back to roost. It comes as no surprise that this pen had no diseases issues.
I have seen other sites that release partridge solely into thick Miscanthus/maize cover. They place the crate facing into the crop and have a line or two of feeders and drinkers the other side. They then walk away and come and collect the crates later in the day. Of course this method requires a lot of fox control, but these sites often report just the same level of returns on partridges at the end of the season. With tighter controls on medications, trials such as these aimed at reducing stress levels on the birds during release can only be a good thing for the progression of the game sector.
Globally, the disease currently affecting poultry in general is Newcastle disease, which for Europe and North America has been quiet over the last decade. However, this year we have seen a rise, with 1 case in Los Angeles in May of this year of the Virulent Newcastle disease (VND) in a small back yard flock of chickens and there has also been 13 outbreaks of VND in Belgium with 2 of these sites being of commercial poultry and the remainder small back yard flocks. VND is what is known as a mild Zoonosis. This means that mild respiratory signs such as conjunctivitis can be seen in humans, however severe symptoms are unlikely to occur.
Interestingly, Belgium vaccinates their birds and therefore there has been some questioning about the efficacy of vaccines against new and emerging strains. Symptoms seen in chickens during this current outbreak have been mild with low mortality, mild respiratory signs or neurological signs. Similar signs can be seen in game birds including unexplained death.
The UK government via DEFRA has declared the threat level to now be MEDIUM to our UK poultry industry. There are several pathways by which the disease could be introduced to the UK: through the movement of live birds, the movement of wild birds, contact with fomites and contaminated equipment, clothing or transport or contact with infected meat and meat products. Since the beginning of June there has been 7 consignments of poultry from Belgium of which 12,000 were gamebirds. These all carried appropriate movement certificates.
As ever we will keep the game industry up to date with any disease developments. In the meantime, I best get off to dusting the gun and getting some clay practice in!