Content
Chlamydia in cattle is one of the causes of infertility in adult queens and a lot of “diseases” in young animals. Like AIDS, chlamydia masquerades as other diseases that could take years to treat. Until the true cause is eliminated, the animals will not recover.
What is chlamydia in cattle?
This is a contagious infectious disease caused by microorganisms of the genus Chlamydia. Externally, chlamydia does not manifest itself in any way. With this infection, the farmer usually believes that his calves are very sick and constantly suffer from colds, indigestion, or conjunctivitis.
With chlamydia, young cattle are “sick”:
- bronchopneumonia;
- rhinitis;
- polyarthritis;
- keratoconjunctivitis;
- gastroenteritis;
- encephalomyelitis.
The latter can also manifest itself in adults. Chlamydia bulls are “beaten” by what is most valuable. Males develop orchitis and urethritis. In cows infected with chlamydia, the following is observed:
- mastitis;
- premature birth of non-viable or dead calves, usually such abortion occurs at 7-9 months of pregnancy;
- in aborted uteruses, the separation of the placenta is delayed;
- development of endometritis;
- long-term infertility.
Because of this diversity, it is very difficult to “catch” chlamydia. The basis for suspicion of chlamydia may be the mass manifestation of various “diseases” at the same time.
The causative agent of chlamydia in cattle
The intracellular obligate parasite Chlamydophila psittaci is common to birds, mammals and humans. Infection with this microorganism in cattle is called chlamydia; in humans, this disease is known as psittacosis (psittacosis).
In addition to Chlamydophila psittaci, chlamydia in cattle can be caused by its subspecies Chlamydophila abortus. Therefore, while in humans, chlamydia infection usually looks like the onset of the flu, then abortions may occur in cows.
Chlamydia differ from viruses in the presence of DNA and RNA and are part of an intermediate group between bacteria, viruses and rickettsia. Chlamydia has an oval or spherical shape. Being the same species, chlamydia can exist in two types:
- intracellular form in the form of reticular bodies with a diameter of 1.2 microns, the structure of these bodies is typical of gram-negative bacteria;
- viral form with a body diameter of 0.3-0.4 microns.
Just like gram-negative bacteria, chlamydia is sensitive to the tetracycline group of antibiotics.
Parasites are relatively stable in the external environment:
- water – up to 17 days;
- unpasteurized milk – 23 days;
- in products processed by lyophilization (dehydration after freezing) – up to 3 years;
- at a very low temperature - almost forever or as long as frozen sperm of a sick bull will be stored.
At the same time, chlamydia is very sensitive to high temperatures. They can be easily neutralized with disinfectants in normal concentrations.
Chlamydia under a microscope
Routes of transmission of chlamydia
The potential hosts of chlamydia are very different animals. So much so that they should not have common infectious diseases. However, chlamydia is one of these. Carriers of chlamydia can be:
- birds;
- cattle;
- horses;
- pigs;
- sheep;
- People.
A sick body releases chlamydia into the external environment in several ways:
- with sperm;
- when exhaling air;
- with milk;
- with feces;
- with urine;
- during abortion and childbirth.
Accordingly, infection of cattle with chlamydia also occurs in several ways:
- aerogenic;
- orally when eating infected food;
- during mating or artificial insemination using bull sperm from a farm unaffected by chlamydia.
Chlamydia in cattle is also dangerous because, once it enters a farm, it remains there for years. Young animals constantly develop pulmonary, gastrointestinal, joint and eye diseases. A decrease in the productivity, reproduction and safety of cattle leads to large financial losses. Disinfection of farms against chlamydia is also very expensive.
The birth of non-viable calves is one of the signs of chlamydia on the farm
Forms of chlamydia in cattle
There are 5 forms of the disease in cattle. The type of chlamydia depends on where the infection occurs. The form of chlamydia can be:
- genital;
- intestinal;
- encephalitis;
- respiratory;
- conjunctival.
Symptoms of chlamydia in cattle
What all forms of bovine chlamydia have in common is an incubation period that lasts from 3 to 20 days. Otherwise, they can be very different from each other.
Genital
Development of endometritis and metritis. Retention of placenta and abortion. Excessive walking, sometimes infertility is observed in cows. Such symptoms are also possible with non-contagious hormonal imbalances.
Chlamydial abortion often occurs together with other infectious diseases:
- brucellosis;
- streptococcosis;
- salmonellosis;
- vibriosis;
- trichomoniasis.
In such cases, adult queens often die due to general septicemia.
When the genital form of chlamydia develops in a bull, the infection causes inflammation of the testicles (orchitis) and urethritis. Orchitis may not be infectious, but traumatic in nature. In this case, the development of chlamydia will go further.
Signs of orchitis in a bull:
- swelling of the scrotum;
- tenderness in one or both eggs;
- general oppression;
- increased body temperature;
- rare bouts of anxiety.
In an attempt to relieve pain in the groin, the bull moves his hind leg outward and struggles to carry it forward.
Urethritis is an inflammation of the mucous membrane of the urethra, which most often occurs for a non-infectious reason. The main symptoms in a bull:
- admixture of blood, pus and mucus in the urine;
- frequent urination;
- erection of the penis.
If you make a diagnosis based only on anamnesis, it is easy to make a mistake. A laboratory urine test will most likely show the presence of chlamydia. Provided that a test for chlamydia is done.
Orchitis is a symptom not only of chlamydia
Intestinal
Signs of the intestinal form may resemble viral diarrhea:
- temperature 40-40.5 °C;
- loss of appetite;
- general oppression;
- diarrhea;
- hyperemia of the mucous membrane of the mouth;
- sometimes the presence of pasterosions and ulcers.
Symptomatic treatment in this case will not give results.
Encephalitic
If the parasite manages to penetrate the nervous system, cattle develop chlamydia of the encephalitic type. Cattle show signs of central nervous system damage:
- uncoordinated movements;
- cramps of the neck and neck muscles;
- head shaking.
Symptoms of central nervous system damage usually appear shortly before death, in which case the cow is unlikely to be saved.
Respiratory
This form of chlamydia can be confused with a good half of respiratory tract diseases:
- fever;
- the temperature of 40-41 °C lasts only the first 1-2 days, later dropping to normal;
- serous discharge from the nose turns mucopurulent after 3-4 days;
- the nasal mucosa is swollen and hyperemic;
- cough;
- rapid pulse;
- conjunctivitis or slight swelling of the eyelids;
- frequent breathing.
With this form of chlamydia, the farmer often tries to treat cattle with folk remedies.
Conjunctival
The name of this form speaks for itself. Keratitis, lacrimation and conjunctivitis are observed.
One of the consequences of chlamydia infection
Diagnosis of the disease
The primary diagnosis is made on the basis of clinical signs and epidemiological data. The final determination is made after laboratory and pathological studies.
To make a diagnosis of chlamydia, samples of blood, feces and swabs from the conjunctiva and nasal cavity are taken from a patient with cattle. Blood serum samples are taken for serological testing: in the first days of the appearance of clinical signs and after 2-3 weeks. Samples of internal organs are taken from forcedly slaughtered or dead animals:
- mucous membranes of the trachea, nasal cavity, larynx;
- spleen;
- lungs;
- rennet;
- small intestine;
- medulla oblongata;
- synovial membrane of joints;
- dura and soft meninges.
During abortions, vaginal mucus and pieces of the placenta of aborted uteruses, the contents of the abomasum and the parenchymal organs of the fetus are taken. Ejaculate, sperm samples and swabs from the prepuce are collected from bulls. Selected materials are delivered to the laboratory frozen.
The diagnosis is considered established if laboratory tests yield the following results:
- the pathogen was isolated and identified from the test material;
- positive results were obtained when testing blood serum for chlamydia;
- there is an increase in antibody titer by 2 or more times when examining blood from aborted uteruses.
Chlamydia must be differentiated from other infectious diseases. The intestinal and respiratory forms of chlamydia in cattle are differentiated from:
- parainfluenza-3;
- infectious rhinotracheitis;
- salmonellosis;
- viral diarrhea;
- adenovirus infection;
- coronavirus enteritis;
- colibacillosis;
- rotavirus infection;
- mycoplasmosis.
The encephalitic form of chlamydia is differentiated from rabies, listeriosis, Aujeszky's disease, and toxicosis.
You don't have to check. Legs hanging in the air are a sign of absence of disease
Pathological changes
When examining fetuses aborted due to chlamydia, the following is found:
- numerous hemorrhages in the epicardium, pleura, endocardium, abomasal mucosa, kidneys;
- serous edema in the subcutaneous tissue;
- granular and fatty liver degeneration;
- in the internal cavities there is hemorrhagic transudate.
Enteritis and ulcerative gastritis are also present.
Necropsy of adult and young cattle
For the respiratory form:
- the mucous membranes of the respiratory tract are swollen and hyperemic, with hemorrhages;
- mucus, often mixed with pus, in the bronchi;
- dense nodules in the lungs;
- enlarged bronchial lymph nodes with hemorrhages.
For intestinal form:
- dystrophy of the kidneys, spleen, liver;
- pinpoint hemorrhages in internal organs;
- inflammation of the intestinal mucosa;
- ulcerative enteritis.
Proliferative fibrinous arthritis usually affects young cattle, but sometimes they also occur in adults.
Treatment of chlamydia in cattle
Once an accurate diagnosis has been established, treatment can begin. “Traditional” antibiotics used in the case of other infectious diseases are useless in the case of chlamydia. They do not act on intracellular parasites. To treat chlamydia, it is necessary to use antibiotics of the tetracycline group. The most effective are teramycin and geomycin retard. A two-time dose of 1 mg/10 kg of live weight is sufficient. The interval between injections is 3-4 days.
The unsanitary condition of the barn is one of the ways of spreading infections
Preventive actions
Preventive measures are prescribed in the sanitary and veterinary rules:
- It is prohibited to keep different types of animals together;
- contact with birds, wild and domestic, should be limited as much as possible;
- the livestock is stocked only with healthy animals from chlamydia-free farms;
- sires are serologically tested for bovine chlamydia in spring and autumn;
- an optimal microclimate is created in the premises.
To build immunity, an inactivated vaccine against bovine chlamydia and the drug “EPL” are used.The latter is administered twice with an interval of 1 day. The required doses are indicated in the instructions for the drugs.
Conclusion
Chlamydia in cattle is an insidious and dangerous disease. Due to the “disguise” as other infections, a farmer may begin to treat cattle on his own, sincerely believing that his cows are not suffering from anything terrible. In this case, the herd owner will miss time and also suffer losses due to abortions. In addition, drinking milk with chlamydia can also make a person sick.
