Gauteng Smallholder August 2015 | Page 38

From page 36 earlier will mean the horses are prone to the disease from administer the two-injection about April, while administervaccine or they handle and ing the injections later means administer the vaccine incorrectly. Or, they neglect a the horses will have built up insufficient immunity in simple disease-prevention January. However it is still programme in their stables worth doing up to the end of from late spring to late summer, when the carrier, the December, if you have not done it before. Culicoides midge, abounds. The two injections are The programme comprises two injections given subcuta- effective against different neously (under the skin) three strains of the disease so both must be administered, weeks apart. It is common practice to administer the inoculations in October/Nov. These months are considered the best time to administer the vaccines, whose efficacy is short-lived, because one wants How NOT to inject a horse in the neck. As it to ensure maxifeels the prick of the needle the horse may mum immunity involutarily jerk its head up and backwards, late in the summer. which can result in the needle breaking off under Administering them the skin. Rather insert the needle pointing backwards. ANIMAL HEALTH otherwise the animal will not build up the full spectrum of immunity to all strains. Similarly, it is important that injected horses should not be worked hard, especially during the second week of each three week period following the injections as this is the time that immunity is maximised. And, the three week gap should also be strictly adhered to otherwise immunity is, likewise, compromised. The vaccine itself is a freezedried culture which is mixed with an ampoule of distilled water before administering and it is important that the vaccine remain refrigerated during storage and transportation, and that the injection be given immediately the vaccine and water are mixed. Good stable management, aimed at limiting the exposure of the horse to the 37 www.sasmallholder.co.za carrier midge, will go a long way to helping prevent the killer scourge of AHS. Moreover, there is only one producer of AHS vaccine in South Africa, namely Onderstepoort Biological Products (OBP). Over the past few years bottlenecks and shortages in the supply of AHS (and some other) vaccines have occurred, so it is worth making enquiries, or placing orders, now for the vaccines you know you will require later this year. Continued on page 38