Table 5-16. RETURN TO CYCLICITY FOLLOWING PARTURITION

Species		Postpartum Estrus/Ovulation:				Fecundity (# pregnancies)
		+ Lactation		-Lactation

Mouse		2 days			2 days				6/year
Horse		9 days ("foal heat")		9 days				1/year
Dairy cow		40 days			30 days				1/year
Beef cow		60 days			30 days				1/year
Sheep		30 days (fall lambing)	10 days				1-2/year
Pig		3 days (anovulatory)		7 days				2-2.5 (early weaning at 3 weeks)/year
Opossum		after weaning (4 months)	10 days				2/year
Rabbit		after weaning (6 weeks)	2 days				5/year
Human		after weaning		within 3 months			1/year
Whale		after weaning (1 year)	within 6 months			1/2.5 years
Elephant		after weaning (2 years)	within 3 months			1/4 years
Bat		next breeding season		next breeding season			1/year
Cat, dog		next breeding season		next breeding season			2/year