The cells of the species were observed as straight rods with rounded ends, arranged singly or in chains and motile. Stained positively in young cultures and gram-negatively in old cultures. Colonies on blood agar were seen dull-white with undulated margin and produced β haemolysis, uniform turbidity also recorded in nutrient broth medium, it did not grow on MacConkey’s agar. Biochemically species was observed that possessed catalase, oxidase, citrate utilization and aesculin hydrolysis properties and considered to be positive. It fermented glucose, mannose, xylose, galactose, creatinin, dulcitol, maltose and mannitol, but did not ferment inositol (Tables 1, 2, 3 and 4). Gabbar (1992) also described almost similar morphological, staining and cultural characteristics, whereas Dewani (2000) reported that Bacillus cereus produced a variety of colonies from small shiny compact to large feathery and spreading types. They observed positive interaction with Voges-Proskauer and negative to methyl red and urease. It fermented glucose, mannose, xylose, galactose, creatinin, dulcitol, maltose and mannitol, but did not ferment inositol.

The organisms of this specie were straight, slightly curved short rods, arranged singly, in pairs, V forms and small clusters. Non-motile, gram-positive but also stained irregularly and sometimes considered to be acid-fast. The colonies on blood agar were seen gray-white, convex, entire and produced β haemolysis. It produced granular and pellicle growth in nutrient broth. It did not grow on MacConkey’s medium. Corynebacterium pyogenes did not show catalase, aesculin, urease and nitrate reduction properties when tested for different chemicals. It produced K/A that means alkaline slant and acidic butt and did not produce H₂S in TSI agar. It fermented glucose, mannose, xylose, galactose, dulcitol and maltose, but did fail to ferment mannitol, creatinin and inositol (Tables 1, 2, 3 and 4). Gabbar (1992) and Shaikh (1999) both described the similar morphological and staining properties of Corynebacterium pyogenes as recorded in this investigation. They observed the morphological and staining characters as small coccoid, pleomorphic bacilli varying from 0.9-1.0µ in diameter. On serum agar, it formed minute dewdrop like colonies (Khan and Rind, 2001 and Shaikh, 1999). They observed that the species interacted positively to gelatin and negatively to catalase, aesculin, urea and nitrate. It produced alkaline slant and acidic butt and did not produce H₂S in TSI agar. It ferment glucose, mannose, xylose, galactose, dulcitol and maltose, but did fail to ferment mannitol, creatinin and inositol.

Figure 1

Table 1: Morphological and staining characteristics of bacterial species identified from mastitic milk samples of camels

Escherichia coli cells were seen as coccobacillary, short rods, arranged singly and in pairs, stained negatively and non-motile. The cultural characteristics recorded were moist, gray, shiny and convex with entire margin colonies, non-haemolytic and easily dispersible in normal saline solution. Uniform turbidity was observed in the nutrient broth. It produced lactose fermentative colonies on MacConkey’s agar (Tables 1, 2, 3 and 4). Khan and Rind (2001) described Escherichia coli as short rods of 0.5-3.0µ with a variable shapes from coccoid bipolar to long rods. Usually occurred singly but short chains were uncommon. The cells were motile and non-spore forming, gram-negative and non-acid fast. On blood agar, non-haemolytic while on MacConkey’s agar, Escherichia coli gave circular, smooth and convex colonies with pink colour. Dewani (2000), Shaikh (1999), Khan and Rind (2001) also demonstrated that Escherichia coli showed positive characteristics of catalase but not oxidase. It exhibited A/A and produced gas in TSI agar. It interacted negatively to indole, urea, Voges-Proskauer, gelatin and citrate, while positively to methyl red and nitrate. The species fermented glucose, mannose, maltose, mannitol, xylose and inositol but did not ferment galactose, creatinin and dulcitol.

Micrococcus luteus was found gram-positive cocci, non-spore forming, non-haemolytic, non-motile aerobic or facultative anaerobes, arranged in pairs, irregular clusters and tetrads. It grew in circular, entire, convex and creamy yellow pigmented colonies heaving 0.5-2.5µ diameter. On MacConkey’s agar, it formed round, opaque and colourless colonies, while on blood agar, it formed cubical packets usually produced colonies with a granular surface and matt appearance. It produced uniform turbidity in nutrient broth medium (Tables 1 to 4). The species showed cubical packets like colonies on blood agar and also produced uniform turbidity in nutrient broth medium were also encountered by Gabbar (1992). Khan and Rind (2001) also recorded similar biochemical properties of Micrococcus luteus as recorded in the present study.

The organism was observed as gram-negative, bipolar and slightly pleomorphic short rods, arranged singly and non-motile. Colonies were mucoid, shiny and convex with irregular margin and β haemolytic with distinctive smell on blood agar. Turbidity growth was observed in nutrient broth medium. Showed its positive interaction with catalase, oxidase, gelatin and nitrate reduction, but did not interact with indole, urea, methyl red, Voges Proskauer and citrate. It produced A/A when cultured on TSI but no H₂S production occurred in TSI agar (Table 1 to 4). Pasteurella haemolytica positively interacted with catalase, oxidase, gelatin and nitrate, but negatively to indole, urea, methyl red, Voges-Proskauer and citrate. Obied (1983), Ramadan et al. (1987) and Dewani (2000) who recorded similar biochemical properties as demonstrated in the present investigation.

Figure 2

Table 2: Cultural characteristics of bacterial species isolated from mastitic milk samples of camels

Organisms showed gram-negative, bipolar and coccobacillary short rods, arranged singly and non-motile. On the blood agar, it exhibited moist, mucoid and shiny growth. The colonies were convex with regular margin and distinctive smell, but not grew on MacConkey’s agar. While in nutrient broth medium, granular deposits were formed in the bottom of the tube (Tables 1 and 2). It interacted positively to catalase, oxidase, indole, gelatin liquefaction and nitrate reduction, but negatively to urea, methyl red, Voges-Proskauer and citrate (Tables 3 and 4). The findings regarding general characteristics of Pasteurella multocida are in agreement to that of Gabbar (1992), Dewani (2000) and Shaikh (1999) who described the cultural characteristics of Pasteurella multocida as non-haemolytic, but some strains produced brownish discolouration on blood agar medium.

Figure 3

Table 3: Biochemical properties of bacterial species identified from mastitic milk samples of camels

Figure 4

Table 4: Sugar fermentation properties of bacterial species identified from mastitic milk samples of camels

Pseudomonas aeruginosa was recorded as gram-negative, straight or slightly curved rods, motile and arranged singly. Culturally, it produced gray-white, large wrinkled, β haemolytic, low convex with irregular margin colonies. On blood agar, it produced a peculiar musty odour, while on MacConkey’s agar, it produced lactose fermentative colonies. Other characters of this species on different media (solid media) as well as in nutrient broth are presented in the same Tables (Tables 1 to 4). Same findings were observed by Khan and Rind (2001), Gabbar (1992) and Dewani (2000). It produced K/N and did not produce H₂S in TSI medium. The organism utilized glucose, mannose, and mannitol, but not galactose, xylose, maltose and inositol and dulcitol sugars.

The cells were gram-positive, cocci, arranged singly/pairs or in irregular clusters. The species was non-motile and non-spore forming. Cultural characteristics observed was a white to yellowish white smooth raised and glistening colonies with circular and entire margin. It produced β haemolysis of red blood cells on blood agar. It produced uniform turbidity in nutrient broth, whereas it did not grow on MacConkey’s agar medium. (Tables 1 to 4). It fermented glucose, mannose, galactose, maltose, inositol, xylose, dulcitol and mannitol sugars, but not utilized creatinin. Gabbar (1992), Khan and Rind (2001), Obied (1983) and Shaikh (1999) also recorded similar characteristics regarding Staphylococcus aureus.