Brucellosis canis is a gram-negative coccidiosis. There are 7 kinds of Brucella, among which dogs are mainly infected with Brucella abortus (bovine type), Brucella Malta (sheep type), Brucella suis (pig type) and Brucella canis. Brucella has no difference in morphology, but there are differences in pathogenicity. Bacillus brucei can grow on ordinary medium, but it grows most luxuriantly on liver soup medium and potato medium. The strain has strong resistance to natural environment and can survive for 20~ 120 days in polluted soil and water. It can survive for 6 months in the fetus and in clothes and fur 150 days. Direct sunlight can survive for 4 hours; If heated at 70℃ for 5 minutes, it will be killed and die immediately after boiling; 2% carbolic acid, Lysol, 0. 1% formalin and 5% fresh limewater can kill this kind of bacteria in a few minutes.
The main sources of infection of the disease are sick dogs and infected dogs; The most dangerous source of infection is the infected pregnant bitch, which excretes a lot of germs with the fetus and placenta during abortion and childbirth, and the vaginal secretions and milk after abortion also contain germs; The semen of infected male dogs contains germs, which can be transmitted to female dogs through mating; The route of transmission is mainly digestive tract and mucosa, and most of them are infected by ingesting feed and drinking water contaminated by bacteria. In addition, it can also be infected through damaged skin and conjunctiva; After dogs are infected with brucellosis, bacteria mainly proliferate in macrophages of lymph nodes, spleen, uterus, placenta and prostate, which can cause infertility or abortion in male and female dogs.
Symptoms of canine brucellosis
Most of them are recessive infections, and a few of them show fever and systemic symptoms; Clinical examination occasionally has fever, lethargy, swollen lymph nodes and weight loss; Sexually mature dogs often show reproductive disorders; Bitch miscarried in the third month after pregnancy, and brown or greenish-gray vaginal discharge after abortion lasted for 1~6 weeks, or infertility or early fetal autolysis, or fetal weakness; Male dogs often suffer from orchitis, prostatitis and testicular atrophy, leading to infertility;
Diagnosis of canine brucellosis
It is difficult to make a diagnosis only from clinical symptoms; Diagnosis requires bacterial culture and identification of blood, semen or tissues (fetus, placenta, spleen, lymph nodes, prostate, etc.). ); Commonly used are rapid plate agglutination test, tube agglutination test and agar gel diffusion reaction; It is suggested to make a comprehensive analysis and finally make a diagnosis;
Prevention and treatment of canine brucellosis
1, if the dog's serum is positive, it should be isolated immediately;
2. Strengthen quarantine and find sick dogs isolated or culled; At present, no effective vaccine has been developed; Contaminated kennels and delivery rooms should be thoroughly disinfected with 10% lime milk or 5% hot alkali, and aborted fetuses, afterbirth, amniotic fluid and vaginal secretions should be properly disinfected or buried deeply; Wear surgical gloves when transporting or handling dogs;
3. Brucella is sensitive to kanamycin, gentamicin, streptomycin and chloramphenicol, and can be treated in isolation for sick dogs; The combined application of vitamin C and vitamin K has a better effect.
4. Don't contact animals and people with brucellosis. The laboratory should deal with sick animals reasonably. People who take care of sick animals should wear protective clothing and wash their hands for disinfection. Air droplet infection can also lead to large-scale occurrence of diseases in experimental facilities;