6. Common Lamb Health Issues

A number of animal health issues can arise in lambs during their first weeks of life. These can include:

· Hypothermia 

· Pneumonia 

· Pink eye 

· Navel ill 

· Pizzle ill 

· Crusty ears 

· Lameness 

· Clostridial disease 

· Parasites 

 · Coccidiosis 

· Bloat 

· Scours 

· Constipation

 6.1 Hypothermia 

Orphaned lambs have a high risk of mortality from hypothermia and starvation, especially during poor weather. 

Symptoms 

· Hunched up and weak (may be unconscious). 

· May be too weak to suckle and their ears and mouth might feel cold. 

· Lambs are considered at risk of hypothermia if they have rectal temperatures below 38.5o C with temperatures at or below 37.5o C considered hypothermic. 

Treatment 

· Get warm colostrum into a newborn hypothermic lamb as soon as possible, using tube feeding if necessary. 

· Warm the lamb by moving it into a warming box, under a heat lamp or submerge in a warm bath. Warm the lamb up slowly – a rapid increase in temperature can kill a hypothermic lamb. 

· 10ml of Ketol (or similar product) can help to give a cold lethargic lamb extra energy. An intraperitoneal injection with dextrose may also be considered if staff are trained with this procedure.

6.2 Navel ill 

Umbilical infection is common in young lambs born into unhygenic conditions and where navel treatment (e.g. iodine dipping) is inadequate. It is often more common in male lambs due to urination delaying drying of the umbilical cord and where urination removes some of the iodine solution. 

 Symptoms 

· Navel feels lumpy/swollen beneath the skin/around the base of the navel. 

· Pus may be secreted from the area, and it may be warm and red. 

· Lamb may have a high temperature. 

Treatment 

· If infected, treat with Penicillin or another antibiotic recommended by your veterinarian, consider antiinflammatories/pain relief in severe cases. 

· Apply topical antibiotic or iodine to the infected area. 

Prevention 

· Ensure lambs are born in sanitary environments where possible. 

· Dip (not spray) the navel in iodine (down to the base) at birth (if lambing indoors) or on entry to the lamb rearing facility. Use an alcohol-based iodine solution to speed up drying of the navel.

6.3 Pizzle/scrotal/navel injury 

Cause 

· Injury to the pizzle, scrotum or navel can occur due to suckling from other lambs. This can be an indication of boredom or hunger. 

Symptoms 

· Wet and inflamed skin. 

· Abrasions and cuts that can become infected. 

Treatment 

· Ensure all lambs are well fed, and supply fibre in the pens to minimise adverse suckling behaviours. 

· Where possible, transition to bigger pens or outdoors by 2-3 weeks of age to avoid this behaviour. 

· Some products are available from Shoof (shoof.co.nz or vet.shoof.co.nz) that may assist (e.g. pepper-based sprays) in reducing these behaviours but data on effectiveness is limited. 

· Spraying the affected area with iodine can also help to reduce suckling (lambs don’t like the taste) and help to prevent infection.

6.4 Pink Eye 

Pink eye (infectious keratoconjunctivitis) is inflammation of the cornea and conjunctiva of the eye. It is caused by one of three kinds of highly contagious bacteria – Chlamydia psittaci (ovis), Mycoplasma conjunctiva, and Moraxella ovis. In addition to close contact with affected animals, stress can play a part in contracting the bacteria (e.g. poor nutrition, over-crowding, new surroundings, extreme weather, transport). Poor ventilation, flies and dust can also help to transfer the bacteria from one animal to another. 

Symptoms 

· The infected eye membranes will be pink/red and inflamed. 

· Tears and wet stains below the eye is common. 

· The animal will blink frequently and may half or fully close their eye(s) due to pain. 

· The eyes are more sensitive to irritants and can be bothered by bright sunlight. 

· An opaque appearance can overcome the eye. 

· Temporary or permanent blindness can occur in severe cases. 

Treatment 

· Follow veterinary advice if the eye appears cloudy. This is likely to include a topical antibiotic in an ophthalmic ointment, and an anti-inflammatory for pain relief. 

· Wipe with a clean cloth with mild disinfectant used for cleaning wounds (do not use the same cloth between lambs as infection can spread). 

· Maintain thorough hygiene standards – unsanitary conditions in the pens can increase the prevalence of the infection.

6.5 Scabby Mouth (orf, contagious ecthyma) 

Scabby mouth is a highly contagious, viral disease. Infections occur through skin abrasions, e.g. cuts to the mouth from vigorous feeding on milk feeders, cuts from hard feeds and/or skin injuries. 

Symptoms 

· Starts with small, reddened areas that begin to weep a clear fluid. 

· Sores and scabs then form. 

· In the early stages, the scab is firmly attached and if removed forcibly, a raw bleeding area is exposed. 

· After 2-3 weeks, the scabs dry up and drop off and the underlying skin heals rapidly. 

 · Commonly affected areas are cool non-woolled areas including the mouth, legs, feet, teats. 

· This disease spreads very rapidly, and once a farm or facility is infected it will remain so. 

Treatment 

· Wear gloves while handling animals with scabby mouths as humans can also be infected. 

· Spray with topical antibiotic spray (or iodine) to reduce secondary infection. 

· In severe cases, lambs may require bottle/tube feeding if the mouth is too sore to allow them to feed. 

· Lambs that recover have lifetime immunity. 

Prevention 

· Vaccination – consider vaccinating with a scratch under the foreleg rather than the hindleg to reduce exposure to other lambs that demonstrate adverse behaviours (e.g. scrotal/pizzle/navel sucking). Consult your local veterinarian. 

· Avoid exposure of lambs to anything that will break the skin and allow entry of the infection. This includes skin injuries from wire, sharp edges on steel pens, nails etc., as well as injury from prickly plants/weeds such as thistles, gorse etc.

6.6 Pneumonia 

Pneumonia is a result of complex interactions between the sheep, environment and microorganisms. Associated microorganisms include bacteria (Mannheimia haemolytica), Mycoplasma (Mycoplasma ovipneumoniae) and viruses (PI3 virus). Dust inhalation can irritate the lung mucosa and predispose them to infection. 

Symptoms 

· Lamb will appear hunched, have droopy ears and dull eyes. 

· May have a cough, runny nose or fever. 

· Breathing is laboured and short. 

Treatment 

· Isolate the animal as pneumonia may be infectious. 

· Treat with antibiotics and anti-inflammatories as directed by your veterinarian. Provide electrolytes in case of dehydration. 

· Identify for follow up treatment. 

· Minimise ammonia build up and deal with dirty bedding, poor ventilation etc. 

Prevention Aimed at minimising stress and optimising animal health. Some suggestions/reminders: 

 · Avoid sudden diet changes. · Avoid dusty feed. 

· Have small mob sizes to reduce animal stress and dust inhalation. 

· Avoid yarding stock in extremes of temperature (high or low). 

· Minimise yarding time. 

· Provide appropriate shelter from extremes of temperature. 

· Minimise stock movement in the middle of the day when dust levels are highest. 

· Ensure good internal parasite control and appropriate vaccinations. 

· Avoid and address any nutritional or mineral deficiencies. 

· Avoid shearing lambs at weaning.

6.7 Entropion (in-turned eyelids) 

Entropion (in-turned eyelid) is a common hereditary problem in many breeds. Inversion of the eyelid is present at birth or can be observed soon afterwards. Discharge from the affected eye(s) rapidly becomes thick and yellow. Severe irritation and ulceration and ultimately blindness in advanced cases occurs from direct contact between the eyelashes and the surface of the eye.

Symptoms 

· Either the lower eyelid or both eyelids will be rolled in causing redness and weeping, and associated with pain. 

Treatment 

· Roll eyelid out by rolling down the skin immediately below the lower eyelid (opposite for the upper lid) and firmly wipe the eye with a clean cloth or finger from the inner to outer edges of the eye to ensure the lid is turned fully out. 

· Pinch the lower eyelid firmly to cause swelling as this will help hold the eyelids out. 

· If this is unsuccessful, an injection 0.1ml of saline solution into lower lid (by a competent operator) can be effective. 

· If the eye is cloudy, discuss treatment with your vet, which may include topical antibiotic in an ophthalmic ointment to control potential secondary infection and provides lubrication to reduce inversion of the lower lid. Depending on severity, other methods such as temporary surgical tacks may help conformation of the eye area. 

Prevention/contol 

Regularly inspect all newborn lambs and treat if required. The genetic component of entropion should be carefully investigated and in cases where the condition can be attributed to particular rams, they should not be retained or sold for breeding.

6.8 Crusty nose and ears 

Lambs in rearing shed often form scabs or crusts on their nose, eyes and ears as a result of dried milk, other lambs chewing/sucking ears, and build-up of residues from solid feeds and powder-based supplements. In severe cases, these areas can be come dried and inflame or /infected causing pain and providing sites for infection from other diseases such as scabby mouth. 

Treatment 

· Wipe with warm water and a soft cloth. 

· Apply topical antibiotic spray or iodine in severe cases where the skin is inflamed or broken to reduce the risk of secondary infection. 

Prevention 

· Avoid the use of powder-based supplements and powdery dried feeds. 

· Ensure lambs are well nourished and are not overcrowded to reduce the incidence of sucking/ chewing from other lambs.

6.9 Dehydration/Starvation 

Symptoms 

· Hunched with a hollow stomach and prominent hip bones (hungry). 

· When pinched, skin will not relax back to normal quickly (dehydrated).

Treatment 

· Provide assistance with feeding and ensure the lamb has had good feed (no more than 350ml in one feed for an average size lamb). 

· If the lamb refuses to suckle and is not dehydrated, consider tube feeding. 

· If the lamb is dehydrated, administer electrolytes. 

· Make the lamb identifiable so it can be retrained onto teat.

6.10 Scald

Scald is the most common cause of lameness in lambs. If left untreated it can lead to footrot which is caused by the pathogen Dichelobacter nodosus. Scald causes the skin between the claws to become inflamed (pink/ red) and to produce a pasty “scum” on the skin that can have a bad smell. It is thought to be caused by abrasion of the skin (e.g. from thistles, hard stalky grass, sharp wood chips) or prolonged exposure to moisture (e.g. in damp weather conditions or soiled lamb rearing pens where the bedding is damp). It can affect appetite and weight gains.

Symptoms 

· Kneeling or severely limping. 

· Red/pink inflamed skin between the hoof claws that is often smelly. 

Treatment 

· Remove any foreign objects. 

· Spray with topical antibiotic spray or foot bath with zinc sulfate-based or formalin products if many animals are affected, carefully following the label recommendations. 

· If severely lame, treat with Penicillin or other antibiotics as directed by your veterinarian. 

6.11 Abomasal Bloat 

Abomasal bloat can affect artificially reared lambs. It is caused by a build-up of bacteria in the stomach (abomasum). Bacteria such as Clostridium perfringens type A and species of Sarcina, have been identified in the stomachs of affected animals. As the bacteria multiply, the sugars found in the milk ferment with excess gas production, and the stomach becomes more acidic which is detrimental to other good bacteria. Bloat develops as the gas cannot escape the abomasum. Death from abomasal rupture is rapid and unpleasant.

Symptoms 

· Lambs with abomasal bloat will have a swollen belly and will be dull and lethargic. 

· Abdominal pain (colic) and teeth grinding (sign of pain) is common. 

· Onset can be rapid, within 30 minutes of feeding and sometimes death is the first sign (i.e. found dead). 

Risk factors 

· Occurs most commonly at 2-4 weeks of age. 

· Infrequent milk feeding (e.g. twice daily). 

· Overfeeding (do not feed more than 350ml per feed when feeding by bottle). 

 · Improper mixing of milk replacer. Mix according to manufacturer’s instructions as diluted milk can cause lambs to gorge, especially on automatic feeders. 

· Hot milk – milk replacer should be fed at body temperature (37-39°C). When Sarcina bacteria are present feeding cold milk may help. 

 · However, if Sarcina bacteria are not present, feeding chilled milk or cold milk replacer can increase the risk of abomasal bloat. 

· Feeding too rapidly (e.g. when teats are damaged or have a large hole) – check frequently and replace when damaged. 

· Poor hygiene (e.g. when bottles/teats and other milk feeding equipment including automatic feeder hoses are not kept clean). Regardless of milk feeding system, good sanitation is required for all equipment. 

 · Milk lines, mixing bowls and teats on automatic feeders should be cleaned at least twice a week.

Tips for preventing bloat 

Maintain good levels of hygiene, avoid overfeeding, and do not feed milk at temperatures higher than 37o C. If good feeding practices, and high hygiene standards are maintained, bloat should be minimal when feeding lambs by bottle, cafeteria or automatic feeder. In multiple AgResearch trials in either research or commercial rearing facilities, when good hygiene practices (e.g. twice weekly cleaning and calibrating of automatic feeders or cleaning feeding equipment after every bottle feed), regular checking of the teats for damage and proper mixing of milk replacers has been applied, bloat was not observed in either restricted milk-fed lambs (bottle/cafeteria) or ad libitum milk-fed lambs (automatic feeders). 

AgResearch trials have also found no evidence for milk replacer composition (e.g. casein vs whey protein) to influence the incidence of bloat. One intervention that can help is to add yoghurt that contains probiotics and prebiotics to the milk. This can be achieved by either adding yoghurt directly to the milk (1 tablespoon per 100 ml milk mixed well, or 1L pottle per 10 L of milk). 

Alternatively, milk can be yoghurtised by adding one packet of probiotic natural yoghurt powder to 10L of warm milk. Keep the mix in a bucket with a lid at 37o C (e.g. in hot water cupboard) until the mixture thickens, and then keep in the fridge for up to 7 days. Add this mix to the milk at a ratio of 1:7 (1 part yoghurt to 7 parts milk). Feed cold or warm. Milk with yoghurt should not be introduced until after 5-7 days of age. This may be an option when feeding a small number of lambs but is not suitable for large-scale rearing units and should not be used as a way to reduce hygiene practices and poor feeding methods.

Treatment 

· Dissolve as much baking soda as possible in 10ml of water and administer orally (e.g. with a syringe). This helps to neutralize the acid. 

· Oral dose of cooking oil (10ml) or antacids may help. 

· Powdered ginger may also help for mild cases (2 tablespoons of ginger mixed in a small amount of warm water administered by syringe). 

· Contact your veterinarian for more advice, especially for pain medication and timely euthanasia if this is not able to be performed on farm by a competent operator.

6.12 Clostridial Disease in Lambs 

Clostridial diseases are common on New Zealand farms and are bacteria that can cause animal welfare compromise, death, decreased profitability. Sheep are susceptible to Clostridial disease at any age, so protection through vaccination prior to birth is important. 

What are clostridial diseases and what are their symptoms? 

 Common Clostridial diseases that can cause illness and death in lambs are: 

· Pulpy Kidney – well fed and fast growing young lambs suffer sudden death. It can also affect grown sheep, particularly when grazing high-quality feed. 

· Tetanus – results from spores entering a wound. Signs appear 10-14 days’ post injury, lambs appear stiff and undergo spasms due to muscle contraction. Can be common following docking. 

· Blood Poisoning diseases; (Animals suffering from the following three diseases are most often found dead. Carcass may be gassy and decompose quickly). 

• Malignant Oedema 

• Black Disease 

• Blackleg

Vaccination Regimes 

· Preventative action in consultation with your veterinarian is best. Ewes should be given a booster vaccine 2-4 weeks prior to lambing. 

· Following birth, artificially-reared lambs should be vaccinated with a 5-in1 vaccine. AgResearch used Covexin 10:1 in trials. First vaccination should take place at 3-4 weeks of age, followed by two boosters, four weeks apart. Following this, all ewes should receive an annual booster.

6.13 Scouring in Lambs (Diarrhoea)

Causes 

Scours in lambs can be caused by many different factors: 

· Bacterial · Viral · Parasites · Diet

During the first few weeks of life, scouring is likely to be caused by nutrition or infection. Infectious scours caused by bacteria, protozoa and viruses will likely have an increased body temperature, depression, dehydration, smelly faeces and perhaps blood in the faeces. Rehydration should be first and foremost for scouring lambs. Use electrolytes to provide energy, water and to replace salts lost during scouring. This will only maintain the lamb so put the lamb back on milk as soon as possible. Medication might be required for serious infections in addition to electrolytes.

 Nutritional Scours 

· This is the most common form of scours in artificially-reared lambs. 

· Results from poor milk replacer quality, poor mixing of milk replacer and/or over-feeding. 

· Avoid diet changes in milk feeding routine (timing, temperature and amount), maintain regular feeding. 

· Don’t allow lambs to drink too quickly. 

· Check that teats don’t allow too much flow that lead to gorging and scouring. 

· High energy diets, and large amounts of molasses in supplement formulations designed for calves can also result in nutritional scours in older lambs.

E. Coli Scours 

· E-coli bacteria thrive in dirty environmental conditions and areas of poor hygiene practices. 

· Occurs when lambs are less than 10 days of age. 

· Lambs salivate and have a cold mouth. 

· Incidence is decreased by good colostrum intake.

Rotavirus Scours 

· Occurs at 2–14 days of age. 

· Symptoms include depressed and dehydrated lambs.

Cryptosporidium Scours 

· Occurs at 5-10 days of age. 

· Causes diarrhoea like that of rotavirus. 

· Very liquid and yellow scouring. 

· Animals that are affected may remain active and continue feeding.

Salmonella Scours 

· Can cause scours at any age 

· Animals that are affected at less than 1 week of age may not show clinical signs and sudden death can occur.

Coccidiosis 

· A protozoan parasite that lambs are susceptible to at 1-4 months of age. 

· Exposure to coccidiosis at a very young age promotes immunity later in life. 

· Disease can be sub-clinical and result in lack of weight gain. 

· Clinical signs usually occur following stressful events such as transport, weaning or changes in feed. 

· Scours may contain blood or mucus, but this is not common. Scours are very watery. 

· Consider feeding solid feeds containing a coccidiostat or monitor animals closely and treat with a longacting coccidiostat if symptoms arise (check the requirements of the market your lambs are entering if selling for meat).

Prevention 

· Maintain clean and hygienic conditions within the lambing area, the rearing shed and all personnel working with the lambs. 

· Ensure footwear is clean and only use gumboots dedicated to the facility. Common Lamb Health Issues 

· Walk through the foot bath and refresh this with Virkon/Vetsan daily. 

· Remove or cover clothing that has been in contact with other livestock since it was last laundered and use dedicated overalls that are kept within the facility. 

· Ensure hands are clean and wear gloves when handling the animals. 

· Feed lambing ewes well to promote the birth of healthy lambs and to promote good colostrum quality and production. 

· Ensuring each lamb receives the recommended number of colostrum feeds. 

· Sterilize all equipment regularly. 

· Avoid overcrowding of pens. 

· There is no scientific evidence that providing lambs access to supplements such as clay, or organic-based powders will prevent scours. 

Treatment 

· Scours can cause lambs to lose a large amount of fluids each day. It is important to ensure lambs are well hydrated (see above for how to check hydration levels). 

· Remove any lambs suffering from infectious scours from the pen and place in hospital pen. Samples of scours can be collected and processed by your local veterinarian/vet lab, to determine the cause which can inform treatment options. 

· Treat affected lambs with electrolytes (Scourban not usually recommended as it contains an antibiotic) and supply milk replacer as recommended by the manufacturer’s instructions. 

· At day four, if the lamb has recovered it can return to a self-feeding group. 

· If the lamb has not recovered at day four, seek veterinary advice. 

· Lambs with nutritional scours are non-infectious and do not require isolation. 

· Ensure all bedding in the lamb rearing pens remains clean and dry – this may require topping up frequently with fresh bedding. 

· Ensure that any contaminated surfaces (e.g. walls and feeders) are regularly cleaned and treated with disinfectant to reduce pathogen loads and risk to other lambs. 

6.14 “Pinning” and constipation 

In the first 2-3 days after birth it is common for faeces to “gum up” around the tail and anus– a condition called “pinning”. This can easily be eliminated by removing the fecal material.

 Constipation can also occur in young lambs, usually in the first week after birth in artificially reared lambs. 

Symptoms 

· Lack of appetite. 

· Straining when trying to defecate. 

· Over-filled stomachs (can be mistaken for bloat). 

Treatment 

· A warm mineral oil enema (10-15 ml) can bring relief if done carefully with a drenching syringe through the rectum. Do not use too much pressure. 

· A 10ml oral dose of olive oil or castor oil, or milk of magnesia (half a teaspoon per 5kg body weight) – mixing with milk and feeding with a bottle can avoid problems with drenching (e.g. inadvertently having the oil go into the lungs)

6.15 Parasites Internal and external 

parasites can cause serious problems in sheep grazed on pasture. Routine drenching with anthelmintic is recommended from two weeks after lambs are given access to pasture. Parasite management is dependent on the risk factors which can vary between farms and regions. It is advised to consult your local veterinarian for advice and to become familiar with the symptoms, risks and treatment or prevention options using readily available information online such Wormwise.

http://wormwise.co.nz/

6.16 Spring eczema

Spring eczema is a problem that occurs sporadically in weaned calves and adult cattle in September-November in many parts of New Zealand and can also occur in sheep. Affected sheep develop photosensitivity lesions on unpigmented parts of the skin (e.g. ears) and/or udder. Causes of spring eczema are still unknown but putative causes include acquired inability of the liver to process high loads of chlorophyll after liver damage (e.g. sporidesmin poisoning), or immaturity of the liver (Collett MG, et al. 2006).

However, dietary ingredients (e.g. storksbill, Erodium moschatum) have also been suggested as a cause in calves. An AgResearch study has also suggested that it may be related to high intakes of grain-based concentrate feeds, low intakes of pasture or poor rumen development during the rearing phase (Stevens et al. 2017). Furthermore, that study suggested exposure to pasture and chlorophyll during early rumen development may be a mitigating factor. Early detection and treatment are essential with immediate removal from sunlight being particularly important.

Treatment 

 · Provide shade. 

· Reduce pasture intake. 

· Provide supplementary feed. 

· Apply sun blocks and disinfectant creams and/or anti-inflammatories (consult your local veterinarian). 

6.17 Acidosis 

Acidosis, or grain poisoning, occurs when sheep eat large amounts of grain. The bacteria in the rumen produce lactic acid which causes acidosis, slows down the gut, damages the gut lining and causes dehydration and often death. Wheat and barley are the most common causes, but it can also occur with oats and lupins. The chances of grain poisoning increase when grains are crushed or cracked by a hammermill as a result of faster release of carbohydrates in the rumen. 

Risks 

· Sudden change to grain feeding (including meal/ concentrates) without gradual introduction to the grain or meal/concentrates . 

· Sudden change to the type of grains or feeding regime 

· Stock grazing paddocks where grain has been harvested providing access to spilled grain. 

· Unplanned access of sheep to grain or pellets. 

Symptoms 

· Depression 

· Lying down 

· Diarrhoea 

· Dehydration and thirst 

· Bloating (left side of the abdomen, i.e. rumen) 

· Stagger or tender gait 

· Death 

Treatments 

· Consult your veterinarian – treatment options vary with the severity of the disease. 

· Treatments may include intravenous fluids, bicarbonate solution or milk of magnesia via drenching, thiamine or steroid injections, antibiotic injections etc. 

· Secondary infections can develop including abscesses in the liver and other organs – these animals often suffer from ill-thrift and require culling.

Prevention 

· Introduce animals gradually to grain or meal/ concentrate. The time required depends on availability of roughage, time of year, type of grain fed and the aim of feeding (e.g. young lambs or lactating ewes). For young lambs this should take at least 2-3 weeks or longer based on research experience. 

· Feed grain daily during the introduction phase (small amounts at a time, e.g. 50 g/head/day for adult animals). 

· Ensure roughage is always available in addition to grain. 

· Monitor animals closely for signs of scouring, depression, lethargy and lameness as this may indicate the amount of grain fed is being increased too fast. 

· Check pulpy kidney vaccinations are up to date and vaccinate before grain feeding if required. 

· Ensure sufficient space for all lambs to feed to avoid competition and overeating.

6.18 Red gut 

Red gut can be caused by rapid passage of high-quality feed (e.g. Lucerne or clover dominant pasture) through the digestive system of the lamb. It usually shows up as sudden death and can be mistaken for pulpy kidney. Autopsies show torsion of the intestines and lack of blood flow. It can be caused by low fibre content of high-quality feed causing rumen capacity to shrink. In addition, higher levels of protein fermented in the large bowel can cause it to expand and twist. 

 Prevention  

· Provide fibre (straw/hay). 

· Graze on these pastures 2 out of 7 days. 

· Mowing and wilting Lucerne prior to grazing. 

· Consult your veterinarian regarding clostridial vaccines as these may help to reduce the incidence.