Nematodirus is a particularly nasty disease in lambs, which can strike quickly causing high lamb mortalities and stunting the growth of many others. It can be seen in cattle but is less commonplace. The battus worm causes the infection which can pass from lamb to lamb and has a different lifecycle to other sheep worms. Fecal Egg Counts (FEC) may not identify the risk initially, as mass hatchings can occur after cold weather followed quickly by a warm spell. This is because non egg producing immature larvae cause most damage. So instead on relying on FEC in this instance, consider if lambs are grazing pasture that carried lambs last spring and if they are now consuming a significant amount of grass -if they are then, they are at risk. The SCOPS Nematodirus Forecast https://www.scops.org.uk/forecasts/nematodirus-forecast/ is based on temperature data from 140 weather stations across the UK and should be utilised to predict risk in a particular region. However, nematodirus eggs can hatch earlier in warmer, more sheltered fields and it is important to consider potential variations from field to field and farm to farm. The class of white (1-BZ) drench is still effective and several treatments at different times may be required, particularly if a longer lambing period results in groups of lambs beginning to graze and inject larvae over a longer period. It is essential to drench correctly and follow all the basic steps as with any oral treatments.
Coccidiosis is another concern particularly for grazing lambs and calves resulting in diarrhoea, poor weight gain, and sometimes death. Coccidiosis is caused by a single celled microscopic Eimeria parasite that multiplies in the intestine of infected animals bursting the cells open damaging the inside lining of the gut reducing the absorptive capacity and causing distress to an animal.
Not all Coccidiosis species are harmful, and many strains exist. The disease causing Eimeria species in cattle or sheep are spread in faeces or by oral contact. They are host specific so calves can be turned out on pasture that held infected lambs or vice versa. Eggs or oocysts can remain though and are very resilient and many disinfectants are ineffective if cleaning sheds so the formulation and dilution rates should be checked. On pasture, oocysts can remain over winter even so if the field was contaminated the previous season pasture rotation the following year should be followed.
Infection therefore can occur in contaminated housing often observed amongst dairy calves. Beef calves or young cattle recently turned out onto pasture can also be at risk. In particular, water courses can become heavily contaminated if the flow of water lessens or only pools remain. These areas where possible should be fenced off and water supplied via mains pipes into a drinking trough. Areas around feeders where ground becomes poached can also become heavily infected especially during warmer weather and should be moved where possible. It is also important to prevent creep feed becoming soiled with animal waste which also applies to housed youngstock too.
Due to the similar symptoms in grazing lambs, it is important to determine if Eimeria or Nematodirus infection is present. Concurrent infection with both parasites is not uncommon, potentially leading to even greater disease severity.
Preventative treatment for both Nematodirus and Coccidiosis is commonly done by oral drench.
Look at your equipment before you start
Weigh-crates need to be accurate, remove any build-up of woolly dags -even consider changing to a digital weighing system upgrading the faithful and well used dial scale.
Drench guns need to deliver the correct dose and chambers and valves need to be clean and lightly lubricated. Tubes also need to be securely in place and clean. Fit non kink springs when attaching to a drench pack if possible. All factors that can cause air bubbles to form. Regular cleaning with warm soapy water after use assists the longevity and accuracy of drench guns.
Weigh animals to remove guesswork and risk of under-dosing
Consider splitting batches when treating if there are large age and/or weight variations and always dose to the heaviest in the batch
Read the drench instructions and check the sell by date
Shake white (1-BZ) drench thoroughly before you start treatment
Set the drencher dosage rate and check the right amount is being delivered using a calibration tube, the neck of a larger syringe with needle removed, or a container with accurate calibration marked on
Squirt three or four doses and check the level each time, air bubbles coming through, resistance and worn springs all affect accuracy
Service kits are available for some drenchers or replace old guns with a new purchase
Sheep can suffer serious injury, or even death, if unrestrained and the gun penetrates the tissues at the back of the mouth. Smaller lambs drenchers in particularly are available with smaller nozzles
Make sure sheep are properly restrained and can’t leap around when drenching, so they swallow the whole amount
Place a hand under the head and tilt slightly to the side. Slot the nozzle in the gap between molar and incisor teeth and then over the back of the tongue. You must get the nozzle over the back of the tongue.
Animal Health Delivery Systems (AHDS) from Simcro and NJ Phillips include a variety of sizes for adult and lamb. They are highly accurate, many with High Flow Valves (HFV) and dual fitting barbs so wider tubes can be used allowing quicker treatment and for thicker drenches to flow through smoothly. They also come with high-quality tubes, connectors and springs preventing kinks in pipes again increasing flow rate and preventing air bubbles. Many in the range possess Service Kits too. Farm Resource Management (FRM) solutions from Tru-Test include EID Stick and Panel Readers so animals possessing an EID tag can have their treatment date recorded. The Tru-Test XRS2 Stick Reader has an Alerts function to identify treated animals and pre-selected animals. Weigh scale indicators with Load bars help to establish the weight of animals to be treated. The Tru-Test S3 records livestock weights onscreen or uses Bluetooth to connect to mobile devices. Livestock Identification Systems (LID) include EID tagging solutions including TagFaster, Z for sheep and Rubba tags offering accurate tagging and reading by EID Stick Readers.