Table 1.

Phenotypic characteristics of hyper-ammonia-producing bacterial isolates* obtained from Nellore steers

Isolate ID**	Cell shape/gram staining	Enrich. 1	Cultural characteristics	Mot. 2	Spore	Maximum OD 3	SAD 4	NH 3 5
C11	Rod-shaped. Gram +	15	White/small colony6	+	-	0.631 ± 0.025	114.85 ± 3.14	34.30 ± 1.88
C33	Rod-shaped. Gram +	15	White/large colony8	+	+	0.820 ± 0.091	129.46 ± 2.87	37.25 ± 3.67
C34	Rod-shaped. Gram -	15	Translucent/small colony	-	-	0.776 ± 0.052	112.69 ± 1.23	34.44 ± 1.15
C37	Rod-shaped. Gram +	15	White/small colony	+	+	0.681 ± 0.001	101.25 ± 4.57	33.29 ± 3.47
C47	Rod-shaped. Gram +	1.5	White/small colony	-	+	0.575 ± 0.037	146.47 ± 2.51	34.87 ± 0.46
C48	Rod-shaped. Gram +	1.5	White/small colony	+	+	0.647 ± 0.071	129.48 ± 2.85	41.29 ± 3.93
C51	Rod-shaped. Gram +	1.5	White/small colony	+	+	0.637 ± 0.016	106.86 ± 1.25	36.21 ± 0.88
C54	Rod-shaped. Gram +	1.5	White/medium colony7	-	+	0.562 ± 0.041	128.01 ± 3.98	28.35 ± 2.01
C89	Rod-shaped. Gram +	15	Translucent/medium colony	-	+	0.675 ± 0.045	203.27 ± 5.76	33.65 ± 1.83
C114	Rod-shaped. Gram +	1.5	Translucent/small colony	+	+	0.434 ± 0.039	278.25 ± 4.65	33.90 ± 0.96
C116	Rod-shaped. Gram +	15	Translucent border and black center/medium colony	-	+	0.332 ± 0.015	286.45 ± 1.32	25.15 ± 5.21
C117	Rod-shaped. Gram +	15	Translucent border and black center/medium colony	+	+	0.671 ± 0.048	186.98 ± 2.03	39.99 ± 1.69
C118	Rod-shaped. Gram +	15	Translucent border and black center/medium colony	-	+	0.609 ± 0.092	222.70 ± 3.04	34.15 ± 0.25
C122	Rod-shaped. Gram +	15	Translucent/large colony	+	-	0.647 ± 0.045	283.41 ± 3.15	35.09 ± 1.98
R15	Rod-shaped. Gram +	15	Translucent/small colony	+	+	0.601 ± 0.022	143.75 ± 2.53	39.02 ± 2.01
R21	Rod-shaped. Gram +	1.5	Yellow/medium colony	+	-	0.577 ± 0.016	469.23 ± 6.76	26.01 ± 3.62
R23	Rod-shaped. Gram +	1.5	Translucent/medium colony	+	-	0.838 ± 0.093	608.18 ± 7.31	30.88 ± 6.25
R34	Rod-shaped. Gram +	15	Translucent/small colony	+	+	0.742 ± 0.056	432.04 ± 4.08	44.17 ± 4.82
R36	Rod-shaped. Gram -	15	White/medium colony	-	-	0.561 ± 0.037	298.91 ± 2.29	33.33 ± 1.19
R40	Rod-shaped. Gram +	15	White/large colony	+	+	0.594 ± 0.048	180.92 ± 2.97	30.59 ± 2.05
R50	Rod-shaped. Gram +	1.5	Translucent/medium colony	+	+	0.660 ± 0.008	371.16 ± 4.47	38.01 ± 0.87
R51	Rod-shaped. Gram +	1.5	Translucent/small colony	-	+	0.662 ± 0.089	207.05 ± 1.64	26.55 ± 3.44
R60	Rod-shaped. Gram +	1.5	White/large colony	-	+	0.406 ± 0.032	475.22 ± 8.91	27.42 ± 7.24
R61	Rod-shaped. Gram +	1.5	Translucent/medium colony	-	+	0.435 ± 0.015	492.63 ± 6.03	27.42 ± 7.31
R63	Rod-shaped. Gram +	1.5	Translucent/large colony	+	+	0.415 ± 0.076	394.92 ± 3.87	25.47 ± 9.97
R90	Rod-shaped. Gram +	15	Translucent/large colony	+	+	0.612 ± 0.077	345.80 ± 4.69	27.31 ± 3.22
R91	Rod-shaped. Gram +	15	Yellow/large colony	+	+	0.535 ± 0.015	332.12 ± 3.36	32.50 ± 5.18
R96	Rod-shaped. Gram +	1.5	Yellow/medium colony	-	+	0.421 ± 0.045	381.73 ± 4.05	21.04 ± 6.53
R97	Rod-shaped. Gram +	1.5	Yellow/medium colony	-	+	0.573 ± 0.106	440.90 ± 6.48	21.55 ± 6.25
R107	Rod-shaped. Gram +	15	White/large colony	+	+	0.546 ± 0.080	197.60 ± 3.54	32.32 ± 1.59

*The isolates were cultured in anaerobic mineral medium supplemented with 15 g l⁻¹ trypticase for up to 48 h at 39°C.

**C, isolates obtained from animals not supplemented with casein; R, isolates obtained from animals that received ruminal infusion of casein.

Symbols: (+) present; (−) absent.

¹Concentration of trypticase (g l⁻¹) used in enrichment cultures; ²Motility; ³Maximum optical density (600 nm); ⁴Specific activity of deamination (nmol NH₃ mg protein⁻¹ min⁻¹); ⁵Ammonia (mmol l⁻¹); ⁶small colony (≤0.5 mm); ⁷medium colony (>0.5 ≤1.0 mm); ⁸large colony (> 1.0 mm).

Values are provided as the mean ± standard deviation of the mean.