Twenty (10%) of 200 milk samples collected from different individual camels inhibited growth of one or more of six pathogenic test organisms in a filter-paper disk assay. The milk samples with inhibitory properties scored zero in the California Mastitis Test. The percentages of milk samples which inhibited Clostridium perfringens, Staphylococcus aureus, Shigella dysenteriae and Salmonella typhimurium were 7.5, 4.0, 2.0 and 1%, respectively. None of the 200 samples inhibited Bacillus cereus or Escherichia coli. Five milk samples inhibited growth of two test organisms and two samples inhibited growth of three organisms. Inhibition zone diameters ranged from 13.5 mm to 22.0 mm (average of 15 mm) using a disk of 12.5 mm in diameter. The average amount of lysozyme in the whey of 58 samples of camel's milk was 288 μg/100 ml. The average lysozyme content of the 20 samples showing growth inhibition of one or more test organisms was 648 μg/100 ml, significantly higher (P<0.01) than the average in the 38 samples (62.6 μg/100 ml) that had no inhibitory effect. There was a negative correlation (r= −0.669) between lysozyme content in the whey of milk samples (y) and the stage of lactation of the camels (x) with the following regression equation: y = −2.86x + 665.8.

The correlation between camels' milk samples collected from abnormal inflamed udders and samples positive in the California Mastitis Test (CMT) was +0.803 (P less than 0.01). The bacterial count ranges of milk samples differed significantly (P less than 0.05) for those with a negative CMT and those with a positive CMT. Infection with many but not all bacterial species was associated with positive CMT results. The highest percentage of camel milk samples was included in the bacterial count range of 3.0 x 10(2) to 3.0 x 10(3) cfu/ml rather than in the greater than 3.0 x 10(3) cfu/ml range for most of the bacterial species. The most predominant bacterial isolates were Micrococcus spp., Staphylococcus aureus, Streptococcus spp. and Corynebacterium spp. followed by eight other flora. Chloramphenicol was the most effective antimicrobial agent of six tested against 118 bacterial isolates. Preliminary observations are made on chemotherapy of mastitis cases in camels.

During the period July, 1980 to June, 1981, 618 samples consisting of mesenteric lymph nodes, spleens and feces, collected from 307 sheep and goats slaughtered in the Riyadh Public Abattoir, were examined for salmonellae. Salmonellae were recovered from 14.7% of 307 lymph nodes, 4.7% of 192 feces and from 0.8% of 119 spleens. Among the 23 serotypes recovered, the most common was Salmonella typhimurium followed by S. newport, S. havana, S. bovismorbificans, S. reading, S. braenderup, S. eastbourne, and S. poona. Other less common serotypes were also encountered. Lymph nodes and feces from slaughtered animals may be a source for contamination of the red meat and other edible parts of the carcase with salmonellae. Consumption of contaminated meat or meat products either raw or undercooked may cause Salmonella food poisoning in man.

Four groups of Dekalb Delta commercial layer hens (8 hens per group) were reared individually in cages in an isolation unit. At the age of 8 weeks, groups 1 and 2 were vaccinated with 9R Salmonella gallinarum live (9R live) vaccine. At the age of 18 weeks, group 1 was re-vaccinated with 9R live S. enteritidis vaccine, while groups 2 and 3 were vaccinated with S. enteritidis bacterin. At the age of 22 weeks, groups 2 and 3 were re-vaccinated with S. enteritidis bacterin. Group 4 was not vaccinated and was kept as a control group. At 24, 27 and 30 weeks of age, the four groups were challenged using various concentrations of S. enteritidis phage type 4 and various routes of inoculation. Eggs, cloacal swabs and blood were collected weekly for bacteriological and serological examination. Isolation of the challenge organism from the eggshells and egg contents of the vaccinated groups was significantly lower than with the control group. There was no correlation between humoral antibodies and the shedding of the challenge organism in eggs or cloacal swabs.A combined vaccination programme of 9R live S. enteritidis vaccine and S. enteritidis bacterin provided better protection to laying hens than either vaccine administered alone. Vaccination should never be performed alone but in conjunction with other measures related to veterinary hygiene and good management.

The World Organization for Animal Health (OIE) Code chapter on FMD includes camelids as being susceptible species to FMD similar to cattle, sheep, goats and pigs. A total of 376 field camel sera, collected from different regions of Riyadh and AlQassim Province in the Kingdom of Saudi Arabia, were screened for the presence of antibodies produced against 3ABC non-® structural proteins (NSP) of FMDV using a commercially available kit , PrioCHECK FMDV NS. Sera that tested positive on NSP were screened for serotype-specific antibodies towards the seven serotypes of FMD virus using liquid phase blocking ELISA. Only 24 out of 376 (6.3%) serum samples were positive for antibodies against NSP. All sera that tested positive on NSP and screened for antibodies against all the seven FMDV serotypes (O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3) were found positive for antibodies against serotype O. This reveals that dromedaries appear however as being susceptible to infection with FMDV serotype O, but they are unlikely to play any significant role in the natural epidemiology of FMD.