Utilization and reproductive performance of gilts in large-scale pig farming system with different production levels in China: a descriptive study

Table 1 Average utilization of 169,013 gilts in 1540 gilts’ batches

		High-performing pig farms (n = 26)	Intermediate-performing pig farms (n = 53)	Low-performing pig farms (n = 26)
		Mean ± SEM	Mean ± SEM	Mean ± SEM
Number	Gilts’ batches	235	948	357
Source	Self-breeding¹	73.0% ± 8.2%^ab	80.8% ± 4.3%^a	54.6% ± 6.7%^b
	Internal introduction²	23.8% ± ± 7.8%	13.2% ± 3.3%	27.4% ± 6.2%
	External introduction³	3.2% ± 1.9%^a	6.0% ± 2.4%^a	18.0% ± 6.2%^b
Introduction	Average introduction number of gilts	121 ± 6.94	83 ± 5.89	174 ± 16.21
	Average introduction age	202 ± 3.76^a	237 ± 1.73^b	224 ± 2.56^c
Mortality	Mortality of gilts⁴	1.8% ± 0.2%^a	1.7% ± 0.2%^a	6.6% ± 1.0%^b
	Total mortality⁵	5.6% ± 0.5%^a	15.4% ± 0.9%^b	19.1% ± 1.4%^c
Culling	Culling rate of gilts⁶	9.4% ± 1.4%^a	10.5% ± 0.8%^a	14.9% ± 1.4%^b
	Total culling rate⁷	25.9% ± 2.0%^a	32.8% ± 1.1%^b	40.4% ± 1.8%^c

¹Self-breeding: Gilts were bred and fed by pig farms themselves
²Internal introduction: Gilts were provided by other pig farms of the internal company
³External introduction: Gilts were provided by the pig farms of the external company
⁴Mortality of gilts = Deaths from introduction to pre-mating/Introduction number of gilts
⁵Total mortality: Mortality during the research stage, regardless of the production phase (pre-mating, mating, conception, farrowing or feeding) of gilts. Total mortality = Deaths during the research stage/Introduction number of gilts
⁶Culling rate of gilts = Number of culling gilts from introduction to pre-mating/Introduction number of gilts. The reasons for culling mainly included abnormal estrus, disease or physiological defects
⁷Total culling rate: Culling rate during the research stage, regardless of the production phase (pre-mating, mating, conception, farrowing or feeding) of gilts. Total culling rate = Number of culling gilts during the research stage/Introduction number of gilts
^a,b,cBars with different letters differ significantly (P < 0.05)

ISSN: 2055-5660