Response of Goats to the Different Routes of Infection by Pasteurella multocida B: 2

Haemorrhagic Septicaemia (HS) is an important tropical disease of cattle and buffaloes caused by Pasteurella multocida B:2. It usually leads to outbreaks causing acute deaths. This study was conducted to determine the response shown by goats following different routes of infection by P. multocida B: 2. Twenty healthy local goats were selected and divided into four equal groups before they were injected with dexamethasone at the rate of 1 mg kg 1 for four consecutive days. On day 4, goats of groups 1, 2 and 3 were inoculatedintratracheal, subcutaneous and intranasal, respectively with 1 ml of inoculum containing 109 cfu mL of live P. multocida B: 2. Goats of group 4 were the negative control receiving no treatment. During the 4-week experimental period, two (40%) goats of group 1 were killed for humane reason; one within 24 h and the other at day 4 post-infection. Three (60%) goats of group 2 were killed, each on days 2, 5 and 14post-infection while two (40%) goats of group 3 were killed on days 20 and 32 post-infection. Post-mortem examination revealed that goats that were killed within the first 2 days post-infection showed lesions typical of HS. Goats that were killed between days 3 and 7 showed evidence of acute pneumonia while those that were killed between days 8 and 14 p.i. showed subacute pneumonia affecting 25% of the lungs. P. multocida B: 2 was successfully isolated from the lungs, lymph nodes, spleens, tonsils, heart blood, livers and subcutaneous fluid of goats of groups 1 and 2 that were killed peracutely. Isolation was successful from the heart blood and subcutaneous fluid of goat of group 2 that were killed acutely on day 5. However, isolation was unsuccessful from goats that were killed after day 14 of infection.