I am a sheep farmer. Recently, a few lambs are reluctant to walk, limp, and have bent metatarsal joints. May I ask the experts what disease is this? How to prevent it?

According to the description, it was judged to be sheep rickets. Rickets is a disease of bone deformation caused by insufficient vitamin D and calcium and phosphorus metabolism in lambs during the growth and development period. It mostly occurs in the early spring of winter.

1. Causes

The disease is mainly seen in insufficient vitamin D content in the feed and insufficient sunlight, resulting in a lack of vitamin D in lactating lambs; improper calcium and phosphorus ratios in the feed of pregnant ewes or lactating sheep. Damp, dirty, and dark pens, indigestion and poor nutrition of sheep, can be the cause of the disease. The grazing ewes have poor autumn fat, insufficient supplementary feeding in winter, and lambing in spring, and lambs are more susceptible to this disease.

2. Diagnosis points

The main manifestations of mildly sick sheep are growth retardation, abnormal addiction, lying down, sluggishness, slow standing on the ground, difficulty bearing weight on limbs, swaying walking gait, or claudication. Palpation of the joints may cause pain. If the course of the disease is longer, the joints will be swollen. The wrist joints, metatarsal joints, and ball joints are more obvious. The long bones are bent, and the limbs can be spread out, resembling a frog. In the later stage, the sick sheep crawled on the ground with the wrist joints, the hindquarters could not be lifted, and the severely ill lay on the ground.

3. Prevention measures

(1) Improve and strengthen the feeding and management of ewes, strengthen exercise and grazing, give more green fodder, supplement bone meal, and increase the sunshine time of young lambs.

(2) Drug treatment: 3 ml of vitamin AD solution can be used for intramuscular injection; 3 ml of refined cod liver oil can be given by gavage or intramuscular injection, twice a week. In order to supplement calcium preparations, 5-10 ml of 10% calcium gluconate solution can be used for intravenous injection (or 10 ml orally); 2 ml of Vitin calcium can also be used for intramuscular injection, once a week for 3 times.

(3)The following methods should be used to prevent and treat the disease in large groups:

① Take 150 units of vitamin D2 per kilogram of body weight per day, orally for 2 weeks.

②Fish meal is 15 grams per day, mixed with feed, and used for 3 weeks.

③ Calcium gluconate powder or multi-dimensional sugar calcium powder 1.5 grams per day, mixed with feed for 1 month.

④For those with severe limb joint deformation, it is advisable to use bamboo boards to fix and correct the joints to promote joint rehabilitation.