The influence of eroding Djallonke genotype on the incidence of diseases and mortalities in Sahelian x Djallonke cross-bred sheep.

Despite cross-breeding of Djallonke and Sahelian sheep due to the higher growth rate and final body weight of the Sahelian breeds over time, little scientific evidence exists on the ability of the crosses to withstand diseases compared to their Djallonke parents. A study involving 700 Djallonke and two crosses of the Djallonke and Sahelian breeds (50% Sahel × 50% Djallonke, 75% Sahel × 25% Djallonke) was conducted, and documented incidence of diseases, parasites and mortalities in these animals. Enteritis, Ehrlichia ruminantium and orf were more prevalent in 25% Djallonke than both 100% and 50% Djallonkes. Similarly, pneumonia was more prevalent in 50% Djallonkes, individuals of all age groups and females than all other genotypes, adults and males, respectively. Enteritis prevalence was also higher in lambs and males than animals of all age groups and females, respectively. Coccidiosis was more prevalent in individuals of all age groups and males, than lambs and females, respectively. More abscess and trauma cases were found in males than females. Higher levels of tapeworm and flea infestations were seen in lambs than weaners and adults. Conversely, more mange mite and tick infestations were seen in adults than weaners and lambs. Higher mortality rates were recorded in all other genotypes, lambs and females than in 100% Djallonke, all other age groups and males, respectively. Higher case fatality rate was recorded in haemoncosis than taeniasis cases. The Sahel x Djalloke crosses are more susceptible to infectious diseases and record higher mortality rates than the pure Djallonke genotypes.