Effects of lambing season, birth type and sex on early performance of lambs

Figures & data

Table 1 Least squares means (±SEM) of body weight at different stages.

		Body weight (kg)
Factors	No. of lambs	Birth (0 days)	Weaning (60 days)	120 days
Lambing season		ns	**	*
Winter	94	3.84 ± 0.13	12.66 ± 0.45	19.79 ± 0.80
Spring	155	3.84 ± 0.07	11.13 ± 0.33	18.03 ± 0.71
Sex of lamb		ns	**	**
Male	123	3.88 ± 0.07	12.81 ± 0.48	22.27 ± 0.88
Female	126	3.80 ± 0.14	11.11 ± 0.30	18.84 ± 0.60
Birth type		**	*	*
Single	215	4.02 ± 0.07	12.28 ± 0.36	19.57 ± 0.55
Twins	34	3.52 ± 0.12	11.10 ± 0.46	17.58 ± 0.65

ns, not significant.

*P < 0.05, **P < 0.01.

Table 2 Least squares means (±SEM) of body measurements (cm) at weaning time (60 days of age) and 120 days of age.

		60 days of age			120 days of age
Factors	No. of lambs	HG	HW	BL	HG	HW	BL
Lambing season		ns	**	*	**	ns	*
Winter	94	43.61 ± 0.72	41.04 ± 0.55	38.16 ± 0.54	66.61 ± 0.69	50.48 ± 0.77	50.16 ± 0.69
Spring	155	42.78 ± 0.47	39.45 ± 0.37	36.66 ± 0.47	64.84 ± 1.46	51.42 ± 0.79	48.48 ± 0.80
Sex of lamb		**	**	*	**	**	**
Male	123	45.85 ± 0.48	41.81 ± 0.42	37.99 ± 0.45	68.42 ± 0.83	52.28 ± 0.62	50.80 ± 0.55
Female	126	41.71 ± 0.42	39.95 ± 0.55	36.26 ± 0.55	60.97 ± 1.26	48.59 ± 0.90	46.76 ± 0.87
Birth type		*	*	*	**	*	ns
Single	215	45.29 ± 0.79	41.98 ± 0.64	38.25 ± 0.60	66.34 ± 0.11	51.72 ± 0.27	49.87 ± 0.63
Twins	34	43.67 ± 0.42	40.50 ± 0.34	36.68 ± 0.43	65.04 ± 0.28	50.78 ± 0.59	48.71 ± 0.91

BL, body length; HG, heart girth; HW, height at withers; ns, not significant.

*P < 0.05, **P < 0.01.

Table 3 Least squares means (±SEM) of ADG (g/day) at different stages.

Factors	No. of lambs	Pre-weaning (0–60 days)	Post-weaning (60–120 days)	Overall (0–120 days)
Lambing season		**	ns	*
Winter	94	211.09 ± 7.54	118.73 ± 12.26	164.91 ± 6.68
Spring	155	185.56 ± 5.52	114.95 ± 10.32	150.26 ± 5.94
Sex of lamb		**	ns	**
Male	123	213.55 ± 7.97	127.49 ± 13.57	170.52 ± 7.30
Female	126	185.17 ± 5.06	108.28 ± 9.12	149.72 ± 5.04
Birth type		*	ns	ns
Single	215	204.65 ± 5.94	121.55 ± 8.80	163.10 ± 4.54
Twins	34	185.0.5 ± 7.74	108.06 ± 14.54	146.55 ± 9.38

ns, not significant.

*P < 0.05, **P < 0.01.