Swine fever: etiology, transmission, signs and treatment and prevention
Awadhesh Kishore and Rakhi Sharma*
Sarvoday Mahavidyalaya, Chaumuhan-281406, Mathura (INDIA)
*Institute for Development of Technology for Rural Advancement, Mathura-281004 (INDIA)
Classical swine fever (CSF) is caused due to classical swine fever virus (CSFV). Transmission is chiefly by oral and oronasal routes. Symptoms include fever upto 105-107 °F; followed by depression, weakness, anorexia and conjunctivitis, purple discoloration of abdominal skin or necrosis and sudden death. No treatment is feasible. Diseased pigs be slaughtered and carcasses buried. Preventive measures may be adapted.
Classical swine fever, CSF, CSFV, Discoloration, Diseased pigs, Etiology, Fever, Prevention, Signs, Slaughter, Sudden death, Swine fever, Transmission, Treatment, Veterinary.
Swine fever is a viral disease. Classical swine fever (CSF) often known as hog cholera or pig plague is a highly contagious disease of pigs and is endemic in Asia, Central and South America, and parts of Europe and Africa. The infection is caused due to its agent classical swine fever virus (CSFV) historically in the past called hog cholera virus (HCV). The virus CSFV belongs to genus Pestivirus in the family Flaviviridae.
Transmission of disease is chiefly by the oral and oronasal routes. Direct contact between animals and their secretions, excretions, semen and blood causes easy transmission of CSF virus. The virus is spread by farm visitors, veterinarians and pig traders from one to another place. Indirect contact through premises, implements, vehicles, clothes, instruments and needles can also transmit the disease. Airborne transmission of this disease is reported over short distances up to one km in study.
A) Peracute signs:
Young pigs may be found dead without any prior sign of this disease. Mostly it is found at the beginning of a farm outbreak.
B) Acute CSF:
Acute CSF is most common kind of swine fever. Fever upto 40.5-41.5 Â°C or 105-107Â°F is the first sign of this disease followed by depression, weakness, anorexia and conjunctivitis. Constipation may even be observed followed by diarrhea or vomiting. Purple discoloration of abdominal skin or necrosis of the tips of extremities like ears, tail and vulva etc may be occurred. Neurological signs like in-coordination, tremors, convulsions and circling may be noticed. Mortality is high i.e. very close to 100% usually within a week of preliminary signs.
C) Chronic CSF:
Chronic CSF occurs with some low virulence strains of virus. CSF strikes in vaccinated herds. Preliminary signs of the disease are weight loss, hair loss, dermatitis, discoloration of skin of abdomen or ears. Patient pigs may recover or relapse.
D) Subclinical CSF:
This type of CSF occurs in pigs those are infected before birth, or those have been vaccinated. However, the signs of the disease are unseen, but they may be infectious to other pigs.
Prevention and control:
No treatment of CSF is feasible so far. This is recommended advice to slaughter the diseased pigs and carcasses buried or incinerated. An effective communication between veterinary authorities, veterinary practitioners and pig farmers is needful. Effective disease reporting method is necessary to be developed. Strict import policy for live pigs, pig semen, and fresh and cured pig meat is necessary to be framed. Quarantine of pigs before admission in to herd must be compulsory. Efficient sterilization or prohibition of waste food fed to pigs is highly recommended. Rendering plants ought to be effectively controlled. Structured serological surveillance may be targeted to breeding sows and boars. Effective pig identification and recording method must be developed. Effective hygiene measures are necessary to protect domestic pigs from the contact with wild boar.