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.

Inoculum-dependent division lag of Bacillus cultures and its relation to an endogenous factor(s) ("schizokinen").

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.

A total of 412 feed samples and 632 litter samples from 15 poultry farms (2 breeding farms and 13 rearing farms) were examined for salmonella. Twelve of these farms had salmonella in litter, five farms had salmonella in the feed and four had salmonella in both feed and litter. Seventeen feed samples (4.13%) and 121 litter samples (19.15%) were contaminated with salmonella. Sixteen salmonella serotypes were encountered, of which six were found in both feed and litter. Salmonella concord and S. livingstone were present in the litter of one breeding farm and its progeny farms. The five most frequently isolated salmonella serotypes in feed and litter were S. concord (17.39%), S. coeln (15.94%), S. livingstone (15.22%), S. manhattan (11.59%), and S. paratyphi B var. java (8.69%). The pathogenicities of those serotypes were determined by calculating their median lethal doses (LD50) 24 and 48 hr postinjection of 1,050 one-day-old broiler chicks via the navel into the yolk sac. The composite 48-hr LD50s (viable cells) were: S. concord, less than 8.8 X 10(3); S. livingstone, 1.1 X 10(5); S. manhattan, 3.5 X 10(5); S. coeln, 1.25 X 10(7); and S. paratyphi B var. java, 1.73 X 10(7).