Joint ill is a bacterial infection that affects newborn lambs. It is often caused by the bacteria Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) entering the body through the umbilicus (navel), which can be wet. It is common in neonatal lambs born into unhygienic conditions and where there is inadequate navel treatment.
Joint ill is observed more often in poor weather, which makes it more difficult for farmers to get their ewes and lambs out to pasture. This means that lambing sheds become cramped making it harder to keep the sheds clean.
Clinical presentation of joint ill
Joint ill occurs when bacteria from the navel spreads to the bloodstream and settles in the joints. SDSD can survive on hay, straw and mud for several weeks (Duncan and Jackson, 2024). If left untreated, joint ill can cause severe polyarthritis and sudden death. Furthermore, the incidence rate of joint ill can be alarmingly high, reaching up to 20 to 50 percent, with mortality rates of affected lambs as high as 20 percent in some instances(Nicholas and Loria, 2014); euthanasia is common on welfare grounds.
Lambs with navel infections often die quickly, but the clinical signs of an infection can include a swollen, painful umbilicus that does not dry out, pyrexia and inappetence, while the signs of joint ill are swollen, stiff, painful joints that are often hot to the touch, pyrexia, inappetence and depression.
Good hygiene and preventative measures
Good hygiene and preventative measures are essential, and maintaining strict hygiene during lambing will help minimise the risk of infections. Lime can be spread on concrete, and clean, deep bedding and dry lying spaces are advisable. Individual pens should be cleaned out after each ewe to minimise the spread of infection.
All lambs should receive 200ml/kg body weight of good-quality ewe colostrum (at least 26.5 percent IgG on refractometer) in the first 24 hours of their lives (Page et al., 2022); receiving antibodies across the gut wall will give them early passive immunity against common environmental pathogens. If this transfer does not occur, then navel problems will rise dramatically.
Ear tagging should be carried out in dry, hygienic conditions and ear tagging equipment should be kept clean. Any equipment used for neonatal lambs, such as stomach tubes and teats, should be sterilised after use.
Treatment of joint ill
Routine prophylactic use of antibiotics is no longer considered appropriate, or indeed permitted under the new Veterinary Medicine Regulations, the welcome measures aimed at reducing or eliminating antibiotic overuse in farming
The ewes and lambs with suspected joint ill should be separated so that they are easy to identify and can be treated and monitored on a daily basis. Treatment for navel and joint infections involves a course of antibiotics, often a long course of penicillin or an amoxicillin-based antibiotic, and an NSAID to make it easier for lambs to move around with the ewe.
For badly affected lambs and those who fail to respond to treatment, euthanasia may be the best option.
Routine prophylactic use of antibiotics is no longer considered appropriate, or indeed permitted under the new Veterinary Medicine Regulations, the welcome measures aimed at reducing or eliminating antibiotic overuse in farming. However, prophylactic antibiotic use still occurs on as many as 19 percent of farms (Duncan and Jackson, 2024) to reduce the risk of infections, which is not best practice or good antimicrobial stewardship.
Desiccating navels
While some farmers spray the navel, dipping is the gold standard as it ensures that the navel is covered in its entirety, which will dry the navel quicker
Desiccating navels is essential to minimise the risk of navel problems. Dipping a lamb’s navel with a 10 percent iodine solution has been a common way to desiccate the navel and help prevent navel infections, and navels should be dipped immediately after birth. Unfortunately, the maternal drive to lick the navel cannot be prevented, particularly in attentive mothers, and so the iodine is often licked off before it dries the navel and so needs to be reapplied. The effect of iodine is also short-lived, and many manufacturers’ instructions advise to apply twice.
During the 2023 to 2024 lambing season there were widespread iodine availability issues and the price has increased in recent years.
While some farmers spray the navel, dipping is the gold standard as it ensures that the navel is covered in its entirety, which will dry the navel quicker. Spraying risks leaving parts of the navel untreated and, therefore, increases the potential for infection.
New advancements in navel care and navel hygiene
NoBACZ Navel was launched during the 2023 to 2024 lambing season. It rapidly disinfects and dries the navel in as little as two hours and seals it with a coloured, natural resin that forms a long-lasting, hydrophobic barrier to protect against bacteria from the environment (Figure 1) (Lovatt, 2024). It can also be used on ear-tagging sites and on ear tags themselves. It can be used in all production animal species including calves and goat kids. NoBACZ Navel is antibiotic-free and consists of a natural polymer and essential metal ions. It can be applied by dipping or spraying and contains a bitter agent that helps to prevent interference by the dam.
During the 2023 to 2024 lambing period, Fiona Lovatt from Flock Health Ltd, past president of the Sheep Veterinary Society and RCVS and European-recognised specialist in sheep health and production, carried out the largest ever navel protection study in lambs to compare NoBACZ Navel with strong iodine (Lovatt, 2024).
The study involved 6,840 lambs from 11 flocks across the UK in a randomised controlled trial (Lovatt, 2024). During the trial, odd-numbered lambs were treated with strong iodine and even-numbered lambs were treated with NoBACZ Navel. Current practices on the farm were observed, so if the farmer normally dipped the lambs’ navels they dipped with iodine or NoBACZ Navel and if they normally sprayed the navels then they sprayed with iodine or NoBACZ Navel. Deaths were recorded for the first eight weeks and weights were monitored.
In the trial, NoBACZ Navel demonstrated superior protection compared with iodine, with a 21 percent reduction in mortality (p=0.0062). Moreover, lambs that had NoBACZ Navel applied to the umbilicus and ear-tagging sites were on average 230g heavier than those in the iodine group at eight weeks.
For every 1,000 lambs treated with NoBACZ Navel rather than strong iodine, farmers can expect 17 more lambs will survive to eight weeks. This represents an extra £2,229 in the farmer’s pocket at point of sale (Statista, 2024). Heavier lambs are also expected, with the study recording 230kg additional live weight per 1,000 lambs at eight weeks (Lovatt, 2024).
As a purpose-built solution for navel care, NoBACZ Navel has been shown to be extremely well tolerated by handlers and stock alike with no adverse reactions reported. Additionally, farmers have reported a reduction in skin irritation when using NoBACZ Navel.
