Rearing young stock on single species grazing systems under irrigation may become very challenging as there is often no alternative species grazing to help reduce parasite burdens on the pasture.
Irrigated pastures grow grass and provide the perfect environment for parasites: shade, moisture and warmth -- conditions which allow parasites to thrive. Constant grazing with the same species allows numbers to build up from early in the season to peak at high levels early autumn.
Regular drenching intervals help to control the parasite burdens, but still young stock may struggle. The problem is that in between drenches young cattle are ingesting immature worms (L3 stage larvae) that go on to mature into adult egg laying worms in about 21 days. These L3 larvae tend to have production-limiting effects as they cause gut damage, which may directly or indirectly lead to appetite suppression. The result is that maximal growth rates may not be attained.
A relatively new product on the market called Alpheus drench capsules is designed to ease calves through this difficult period. The Alpheus capsules are a slow-release drench capsule discharging abamectin for 125 days, which kills incoming larvae as they are ingested thus preventing them from causing gut damage.
Parasites tend to be easier to kill in their L3 larvae stage than as adult worms. The capsule comes with an oxfendazole/ levamisole combined primer drench to kill all adult worms at insertion leaving the abamectin release to carry on killing any ingested larvae. While these capsules are not for everyone, if you are struggling with your young replacements’ health then it is worthwhile discussing the use of these capsules with your veterinarian.
Trace elements are often neglected in young growing stock, with a mish-mash of treatments often thrown at calves with varying success.
The Tracesure range of boluses are designed to give a steady release of selenium, iodine and cobalt for six months, all essential elements for the growth and wellbeing of young stock. Add to this a copasure bolus and all the essential minerals are being given. No need for yarding and all the dramas that go with it and your young stock only need to consume grass and get on with growing to meet the all-important target live weights required for mating next spring.
Finally, don’t neglect a good vaccination programme for your young calves. While leptospirosis and clostridial vaccinations should be high on your list and already done, some of the viral diseases are usually forgotten. Bovine viral diarrhoea (BVD), infectious bovine Rhinotracheitis (IBR) and Para-Influenza type 3 (PI-3) virus are widespread in New Zealand.
Each of these viruses may affect young animals’ growth rates individually, but combined they can be devastating, leading to severe outbreaks of pneumonia, immune suppression and greater susceptibility to parasites.
Hiprabovis 3 is the only trivalent vaccine on the market catering for all three viral pathogens at once. Vaccinating young stock against these viruses ensures they can get on and grow unimpeded by disease.
Talk to your local veterinarian about good practices to get the maximum potential out of your young stock.