Sudden Death in Lambs

Sudden death is sadly a common and frustrating problem in lambs. Whilst many people overlook this, it is important to investigate because many causes of death can be avoided with management practices such as vaccination or targeted treatments.

The main causes of sudden death in lambs include:

Clostridial disease

Clostridial disease is one of the most common causes. Clostridial bacteria naturally inhabit the intestines but if the gut environment changes this can lead to multiplication, production of toxins and death. This generally seen due to increased feed intakes and changes in diet (pasture and grain based). The most common clostridial diseases in lambs are pulpy kidney and lamb dysentery (both covered by vaccination).

Acute pneumonia and septicaemia

Acute pneumonia and septicaemia are also regular post-mortem findings. This syndrome is most often associated with stress. Several bacteria are responsible, including Mannheima Haemolytica and Pasteurella Multocida. These bacteria are found in healthy sheep, however under periods of stress these bacteria multiply, invade the lungs and enter the bloodstream causing septicaemia and death.

Parasites

Parasites can also be a cause of sudden death. Nematodirus battus outbreaks occur when large numbers of Nematodirus eggs hatch simultaneously in fields grazed by lambs (generally 6-12 weeks old). Severely affected lambs can die suddenly This large-scale hatching requires a chilled period followed by a warmer spell and can be predicted. For the current forecast, please visit the SCOPS website or see our website for more details.

Coccidiosis

Coccidiosis occurs in a similar age group to Nematodirus but can occur as early as 3 weeks. Sheep rapidly gain immunity to this parasite through exposure but if they meet a high challenge before this immunity is in place then disease will occur. Scour is a common finding but if severe gut damage occurs then sudden death can result.

Post-mortems are the best way of investigating. To make the most of this, it is vital we choose the best candidates. Lambs should be fresh and not have suffered predation – we can get answers from those missing eyes but it’s hard to get an answer when they are missing most of their vital organs!

We can carry out post-mortems at the practice or we can use APHAs subsidised service. Free carcass collection is often available depending on your postcode. All supplementary testing is included in the price and a full comprehensive report is received making this excellent value for money.

Please call us on 01327 350239 or email admin@towcestervets.co.uk, if you’d like to talk to one of our vets about this service.

Calf Scours – Prevention is Possible!

Scouring calves can be frustrating but prevention is possible through good hygiene, colostrum management and an understanding of the causes of disease on your farm.

1. Good hygiene

• Good hygiene is essential for preventing the build up of infectious pathogens
• Regularly muck out and disinfect calving pens
• Dip navels in iodine immediately after birth and again 4 hours later
• Isolate any sick calves and clean out areas that have been contaminated

2. Colostrum management

• Colostrum gives calves antibodies to help protect them from disease
• Ensure colostrum is of good quality
  • Consider metabolic profiling cows 2-3 weeks before calving to ensure they are in optimum condition to produce high quality colostrum
  • A refractometer can be used on farm to assess colostrum quality
• Ensure calves receive the right quantity of colostrum, quickly enough
  • Calves should receive 3l of colostrum within 2 hours of birth, and a further 3l within 24 hours
  • Blood samples can be taken from calves within the first week of life to assess colostrum uptake

3. Quick and effective treatment

• Isolate scouring calves away from other calves and clean any contaminated areas to prevent spread to other calves
• Give supportive care
  • Keep calves warm and dry; consider using calf jackets
  • Keep calves hydrated with oral fluid therapy
    • Give 1-2l of electrolytes 4 times daily
    • Alternate with milk every 4 hours
  • Diagnose the cause to inform treatment
    • Take a temperature
      • Normal temperature should be 38.0 – 39.5°C
      • A high temperature indicates a systemic bacterial infection
      • A low temperature may occur with severe dehydration
    • Consider the age of the calf since different causes are associated with different ages of calf:

• • • Use an on farm calf scour test kit to diagnose E. coli, Coronavirus, Rotavirus and Cryptosporidiosis
    • Submit a faecal sample
      • We can look at faecal samples in house for coccidia and worm eggs, and carry out a scour test if you haven’t got one on farm
      • We can send faecal samples to the lab to test for Salmonella, E. coli, Cryptosporidiosis, Rotavirus, Coronavirus, Coccidiosis and worms
    • Treat appropriately
      • Antibiotics
        • Injectable antibiotics are essential for treating bacterial infections including E. coli and Salmonella, indicated by a high temperature
        • It is also beneficial to treat calves with antibiotics even if they are infected with viruses or parasites, since they are at higher risk of bacterial infection
      • Anti-inflammatory pain relief
        • Meloxicam (Animeloxan/Meloxidyl) reduces inflammation and pain associated with intestinal disease
      • Specific treatments
        • Cryptosporidiosis can be treated with halofuginone lactate (Halocur)
        • Coccidiosis can be treated with Baycox or Vecoxan
        • Ostertagia can be treated with most wormers
      • Other drugs
        • Steroids or anti-spasmodics may be helpful in severe cases of diarrhoea – talk to a vet about whether these are appropriate

4. Specific preventative measures

• Use diagnosis to inform your prevention strategies
• Cows can be vaccinated for rotavirus, coronavirus and E. coli so antibodies pass to calves in colostrum
• Pasture management is important in controlling coccidiosis and worms
• Talk to a vet about how to tailor a calf scour prevention strategy to your farm

Identifying & Preventing Staggers in Cattle & Sheep

Staggers is caused by low blood concentration of magnesium and affects both sheep and cattle.  It is most commonly seen in adult lactating animals grazing lush, fast-growing grass pasture but we do see a number of cases in housed animals every year.  Magnesium isn’t stored in the body and therefore the main source is from food.  Absorption will vary with how quickly food passes through the digestive tract and there will be a higher demand during lactation. If feed intakes are reduced due to stress, illness or poor weather then this will also affect magnesium absorption.

Magnesium is important in normal neurological function. Clinical signs therefore include:

• Sudden death
• Initial excitability with high head carriage, twitching of muscles and incoordination.
• Separation from the group. Animals may have startled expressions, exaggerated blink reflex and frequent tooth grinding.
• Rapid progression to periods of seizure activity

Animals found with clinical signs require immediate treatment with subcutaneous Magniject whilst waiting for veterinary attention to administer a combination of calcium and magnesium slowly into the vein. Stress should be minimised during this time and unfortunately there is always a risk during treatment that the extra stress could kill the animal. If treatment is successful, animals should be offered concentrates and good forage to prevent relapse.

In cases of sudden death, we can confirm the diagnosis by measuring magnesium concentration in the fluid around the eye soon after death. Blood sampling a few other animals in the group can also be useful as the majority of the group may be affected without showing obvious clinical signs.

Factors influencing the availability of dietary magnesium include magnesium levels in the soil and grass which vary considerably.  High levels of potassium or ammonia on pasture inhibit magnesium absorption.  Lush pastures are low in fibre and increase the rate of passage of food material through the rumen reducing time for magnesium absorption.

In terms of prevention, options include:

• Medicating the sole water supply with soluble magnesium salts such as chloride, sulphate or acetate. These salts aren’t very palatable so follow directions for use carefully.
• Intra-ruminal boluses which give a reliable slow release of magnesium into the rumen over periods of high risk.
• Magnesium buckets though these may not be used by all animals in a group and problems can still occur.
• Supplementation is particularly important during stormy weather when roughage, such as straw, can be beneficial by slowing rumen throughput and allowing time for magnesium absorption.
• Feeding concentrates containing magnesium will also help to provide sufficient amounts.

Newborn Cria Care

Summer is an exciting time for new arrivals! Whilst most camelids manage this period without any problems, by keeping a close eye on newborns, any problems can be spotted and treated early ensuring happy, healthy babies.

Vaccination

Most herds will booster vaccinate pregnant females in the run up to unpacking (between 2 and 8 weeks prior). This aims to boost the level of antibodies in the colostrum conferring protection to the cria. Crias can then be vaccinated around 3 months old with a full primary course.

Newborn care

Newborn crias should be standing within the first 30-60 minutes and nursing within 2-4 hours. Mum should also pass her placenta within 2-4 hours of birth. Navels should be dipped in iodine tincture to help to dry it and to reduce the risk of infection via this route. If crias aren’t nursing within this time frame then they may need help to suckle or try to milk the mum (we appreciate this isn’t very easy!) and feed this to the cria by bottle. Any cria that is struggling should be checked carefully for potential problems such as a cleft palate. Hernias are also quite common so check the umbilical region carefully. Monitor crias to ensure they pass their first poo within 24-36 hours.

Failure of passive transfer (FPT)

Crias are born with no antibodies, making them extremely susceptible to infection. Young camelids get the important antibodies from the colostrum of their dam so ensuring they get their first drink is really important to protect them from infections. Crias should consume 10-20% of their body weight in the first 24 hours of life (equating to 700-1400ml for a 7kg cria).

Crias can fail to absorb antibodies for a variety of reasons but certain situations put them at higher risk. If any of the situations on the list below apply, then we recommend checking your new arrival for failure to absorb enough antibodies, called Failure of Passive Transfer (FPT).

• Low birth weight (<6KG in alpacas and <7kg in llamas )
• Evidence of prematurity (curled ears, unerupted incisors, socks on feet)
• Difficult birthing or caesarean
• Congenital defects (e.g. cleft palate)
• Maternal issues (first time mum, no bond between mum and baby, no milk, mastitis)

Crias should be weighed daily during the first few weeks of life to and crias that aren’t thriving or aren’t putting on weight should also be assessed. They should generally gain 0.1-0.45kg daily.

Crias with FPT are at risk of life threatening infections so it’s important we check early enough that we can correct the problem before this happens. We recommend checking when the cria is around 24-48 hrs old. The check is a quick and easy blood test that can be performed at the surgery. Crias who are shown not to have enough antibodies can then receive a plasma transfusion to boost antibody levels before infections can set in. If your herd does not currently have any plasma available then do let us know and register your interest for our next Blood Drive Day (2023)

Feeding crias

If mum doesn’t have enough milk then supplementation with other products will be needed. In the first 24 hours, colostrum is vitally important. If camelid colostrum can’t be sourced (this may be unlikely!) then goat’s colostrum is the closest alternative, followed by cow colostrum. If sourcing colostrum from a farm, do be aware of the risks of TB, Johne’s and BVD and only source from herds free of these diseases. Powdered colostrum supplements are available but they generally contain very few antibodies in comparison to camelid colostrum so crias who receive these are at much higher risk of FPT. The product with the highest amount of antibodies is called Immucol Platinum and can be sourced via the Camelid Veterinary Services online shop.

If bottle feeding, aim to feed 10-15% of bodyweight over 24 hours split into 2 hourly feeds initially. Crias feed little and often so this aims to replicate this behaviour. Overfeeding can result in milk entering the wrong stomach and can lead to problems. After 24 hours, milk can be used for feeding as crias are no longer able to absorb colostrum, goat’s milk is the closest alternative to camelid milk.