RISK-FACTORS RESPONSIBLE FOR THE APPEARANCE OF INDIVIDUAL CLINICAL SIGNS IN SMALL RUMINANTS IN NORTHERN CAMEROON

A survey was conducted in north and far-north provinces of Cameroon to determine the risk factors responsible for the appearance of clinical signs in small ruminants. Eight flocks, with a total of 141 animals, were visited weekly for 21 months by field agents who noted the appear ance of individual clinical signs. The animals were weighed monthly an d their faeces were collected for coproscopic examination. At the same time, their sera were tested against the following microbes: Mycoplas ma mycoides subsp. mycoides LC, M. capricolum subsp. capricolum subsp. nove, M. agalactiae, M. capricolum subsp. capripneumoniae, Capripoxvi rus and peste des petits ruminants (PPR) virus. The independent variab les were province, season, species, sex, age class, presence of extern al parasites, infestation level by intestinal parasites and seroconver sions. The survey emphasized the influence of species and season on na sal discharges (more frequent for sheep and in the cold dry season). T he prevalence of contagious agalactia syndrome was higher for animals more than one year old and during the cold dry season; furthermore, it was strongly correlated with mycoplasma seroconversion. The seroconve rsion against PPR was concomitant with that against Capripoxvirus. Slo w growth was associated with strongylosis infestation, the presence of external parasites and the PPR-Capripoxvirus seroconversion. Consider ing the high cost of vermifuges and insecticides, only a vaccination c ampaign appears to be suitable. Long-term control measures against par asitical diseases should focus on livestock practices. Hence, it is re commended to compare the productivity of flocks vaccinated with a mixe d PPR-Capripoxvirus vaccine, and reared under different livestock cond itions. (C) 1997 Published by Elsevier Science Ltd.