Effects of backfat caliper score at 110 days of gestation and parity on reproductive performance of backcross binary sows

doi:10.3969/j.issn.1004-1524.20250514

Acta Agriculturae Zhejiangensis ›› 2026, Vol. 38 ›› Issue (8): 1529-1538.DOI: 10.3969/j.issn.1004-1524.20250514

• Animal Science • Previous Articles Next Articles

Effects of backfat caliper score at 110 days of gestation and parity on reproductive performance of backcross binary sows

LI Xiaoxia¹(), WANG Gangfeng², WANG Dayi², CAO Pinghua¹

¹ College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, Henan, China
² New Hope Liuhe Co., Ltd., Beijing 100102, China

Received:2025-07-29 Online:2026-08-25 Published:2026-09-14

Abstract

Abstract:

Production records of 1 072 backcross binary sows from a breeding farm in Guizhou Province were analyzed using one-way ANOVA and correlation regression to evaluate the effects of backfat caliper score at day 110 of gestation and parities on reproductive performance of sows. The practical utility of the caliper scoring system in sow production management was further evaluated. The results showed that: 1) Parity significantly (p<0.05) influenced the reproductive performance of backcross binary sows, with optimal performance observed in parities 1-4 and marked declines after parity 7. 2) In primiparous sows, the group of caliper score ≤17 demonstrated the highest total number of born, number of born alive, and number of healthy born. This group also had significantly greater litter birth weight and weaning weight of piglets than the >22 group. Both the (17, 20) and [20, 22] groups exhibited significantly higher average piglet birth weight compared with the other groups. Additionally, their litter birth weight and piglet weaning weight were also significantly greater than those observed in the >22 group. For multiparous sows, the group of caliper score ≤17 had the highest reproductive performance, followed by the (17, 20) group. 3) Extremely significantly (p<0.01) negative correlations were observed between backfat caliper scores and litter birth weight, birth weight, and weaning weight of the piglets in primiparous sows, with optimal reproductive performance achieved at scores of 19-21. Whereas, the number of born alive and litter birth weight of piglets were significantly negatively correlated with the caliper score of multiparous sows, and the scores were better at 18-20 points. In conclusion, the reproductive performance of backcross binary sows is optimal during parities 1-4, and culling is recommended after parity 7; the backfat caliper score for primiparous sows should be maintained within 19-21, while that for multiparous sows should be kept at 18-20.

Key words: parity, caliper score, binary backcross sow, reproductive performance

CLC Number:

S828

LI Xiaoxia, WANG Gangfeng, WANG Dayi, CAO Pinghua. Effects of backfat caliper score at 110 days of gestation and parity on reproductive performance of backcross binary sows[J]. Acta Agriculturae Zhejiangensis, 2026, 38(8): 1529-1538.

Figures/Tables 9

References 35

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体况 Body condition	卡尺评分 Caliper score	背膘厚度/mm Backfat thickness/mm
极瘦Emaciated	<15	<13
偏瘦Thin	[15, 17]	[13, 15]
标准Ideal	(17, 20)	(15, 18)
偏肥Heshy	[20, 22]	[18, 20]
过肥Obese	>22	>20

体况 Body condition	卡尺评分 Caliper score	背膘厚度/mm Backfat thickness/mm
极瘦Emaciated	<15	<13
偏瘦Thin	[15, 17]	[13, 15]
标准Ideal	(17, 20)	(15, 18)
偏肥Heshy	[20, 22]	[18, 20]
过肥Obese	>22	>20

胎次 Parity	样本数 Sample number	总产仔数 Total number of born	产活仔数 Number of born alive	健仔数 Number of healthy born	畸弱数 Number of weak or malformed piglet	死胎数 Number of stillbirths	木乃伊数 Number of mummified fetuses
1	521	11.88±1.83 a	11.46±1.83 a	11.15±1.79 ab	0.32±0.74 a	0.24±0.65 a	0.17±0.53 a
2	121	11.71±1.97 ab	11.39±1.90 ab	11.17±1.86 a	0.21±0.62 a	0.26±0.57 a	0.07±0.34 a
3	83	11.53±1.84 abc	11.16±1.87 ab	10.89±1.85 ab	0.27±0.52 a	0.27±0.70 a	0.11±0.44 a
4	41	11.66±2.64 ab	11.24±2.84 ab	10.90±2.68 ab	0.34±0.76 a	0.34±0.69 a	0.07±0.26 a
5	121	11.17±2.14 abc	10.74±2.26 ab	10.57±2.21 abc	0.17±0.51 a	0.26±0.69 a	0.17±0.48 a
6	90	11.10±2.38 abc	10.78±2.32 ab	10.53±2.15 abc	0.24±0.72 a	0.26±0.59 a	0.07±0.29 a
7	27	10.74±2.57 cd	10.52±2.99 bc	10.26±2.85 bc	0.26±0.86 a	0.11±0.58 a	0.11±0.42 a
8	49	10.86±2.21 bcd	10.53±2.17 bc	10.43±2.14 abc	0.10±0.37 a	0.20±0.61 a	0.12±0.39 a
9	19	10.16±2.24 d	9.84±2.22 c	9.74±2.21 c	0.11±0.32 a	0.26±0.45 a	0.05±0.23 a

胎次 Parity	样本数 Sample number	总产仔数 Total number of born	产活仔数 Number of born alive	健仔数 Number of healthy born	畸弱数 Number of weak or malformed piglet	死胎数 Number of stillbirths	木乃伊数 Number of mummified fetuses
1	521	11.88±1.83 a	11.46±1.83 a	11.15±1.79 ab	0.32±0.74 a	0.24±0.65 a	0.17±0.53 a
2	121	11.71±1.97 ab	11.39±1.90 ab	11.17±1.86 a	0.21±0.62 a	0.26±0.57 a	0.07±0.34 a
3	83	11.53±1.84 abc	11.16±1.87 ab	10.89±1.85 ab	0.27±0.52 a	0.27±0.70 a	0.11±0.44 a
4	41	11.66±2.64 ab	11.24±2.84 ab	10.90±2.68 ab	0.34±0.76 a	0.34±0.69 a	0.07±0.26 a
5	121	11.17±2.14 abc	10.74±2.26 ab	10.57±2.21 abc	0.17±0.51 a	0.26±0.69 a	0.17±0.48 a
6	90	11.10±2.38 abc	10.78±2.32 ab	10.53±2.15 abc	0.24±0.72 a	0.26±0.59 a	0.07±0.29 a
7	27	10.74±2.57 cd	10.52±2.99 bc	10.26±2.85 bc	0.26±0.86 a	0.11±0.58 a	0.11±0.42 a
8	49	10.86±2.21 bcd	10.53±2.17 bc	10.43±2.14 abc	0.10±0.37 a	0.20±0.61 a	0.12±0.39 a
9	19	10.16±2.24 d	9.84±2.22 c	9.74±2.21 c	0.11±0.32 a	0.26±0.45 a	0.05±0.23 a

胎次 Parity	样本数 Sample number	初生窝重/kg Litter birth weight/kg	初生重/kg Average piglet birth weight/kg	断奶数 Number of weaned piglets	断奶率/% Weaning survival rate/%	断奶重/kg Weaning weight of piglets/kg
1	521	14.96±2.90 a	1.30±0.17 abc	10.84±2.08 ab	94.54±12.60 a	6.78±0.53 bcd
2	121	15.06±2.54 a	1.33±0.08 ab	10.72±2.44 ab	93.64±14.41 a	6.94±0.30 ab
3	83	13.96±2.83 ab	1.25±0.14 c	10.93±1.97 a	97.93±5.46 a	6.60±0.51 d
4	41	14.09±3.77 ab	1.26±0.16 c	10.32±2.50 ab	92.78±11.63 a	6.96±0.19 ab
5	121	14.18±3.03 ab	1.32±0.11 ab	10.36±2.62 ab	95.70±13.20 a	6.77±0.50 bcd
6	90	14.33±3.05 ab	1.33±0.08 ab	10.34±2.20 ab	96.43±8.01 a	6.93±0.20 ab
7	27	13.32±3.73 b	1.28±0.12 bc	9.85±2.81 bc	94.93±12.43 a	6.74±0.30 cd
8	49	14.08±2.85 ab	1.34±0.10 a	9.94±2.56 abc	94.35±12.92 a	6.90±0.31 abc
9	19	13.19±2.88 b	1.35±0.09 a	9.21±2.80 c	92.47±17.96 a	6.99±0.17 a

Effects of backfat caliper score at 110 days of gestation and parity on reproductive performance of backcross binary sows

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类别 Sort	卡尺评分 Caliper score	样本数 Sample number	总产仔数 Total number of born	产活仔数 Number of born alive	健仔数 Number of healthy born	畸弱数 Number of weak or malformed piglet	死胎数 Number of stillbirths	木乃伊数 Number of mummified fetuses
初产母猪	≤17	17	12.47±0.87 a	12.41±0.94 a	12.00±1.17 a	0.41±0.71 a	0.06±0.24 b	0 a
Primiparous	(17, 20)	131	11.99±1.77 a	11.44±1.70 b	11.16±1.82 b	0.39±0.84 a	0.38±0.93 a	0.18±0.49 a
sows	[20, 22]	306	11.91±1.81 a	11.55±1.73 b	11.20±1.71 b	0.25±0.67 a	0.21±0.54 ab	0.15±0.46 a
	>22	67	11.39±2.18 a	10.93±2.49 b	10.69±2.48 b	0.24±0.61 a	0.16±0.48 ab	0.30±0.89 a
经产母猪	≤17	42	11.64±2.17 a	11.38±2.29 a	11.07±1.94 a	0.31±0.98 a	0.24±0.58 a	0.02±0.15 a
Multiparous	(17, 20)	209	11.41±2.41 a	11.10±2.49 a	10.89±2.40 a	0.20±0.55 a	0.23±0.57 a	0.09±0.34 a
sows	[20, 22]	254	11.06±2.11 a	10.70±2.11 a	10.50±2.07 a	0.22±0.60 a	0.24±0.57 a	0.12±0.43 a
	>22	46	11.59±1.39 a	11.02±1.45 a	10.78±1.58 a	0.24±0.52 a	0.41±1.09 a	0.15±0.42 a

类别 Sort	卡尺评分 Caliper score	样本数 Sample number	初生窝重/kg Litter birth weight/kg	初生重/kg Average piglet birth weight/kg	断奶数 Number of weaned piglets	断奶率/% Weaning survival rate/%	断奶重/kg Weaning weight of piglets/kg
初产母猪	≤17	17	15.42±2.77 a	1.24±0.17 b	11.47±0.94 a	92.67±7.55 a	6.86±0.23 a
Primiparous	(17, 20)	131	15.23±2.92 a	1.33±0.15 a	10.70±2.31 a	93.35±14.41 a	6.83±0.34 a
sows	[20, 22]	306	15.18±2.67 a	1.32±0.15 a	10.91±1.94 a	94.81±11.66 a	6.85±0.39 a
	>22	67	13.30±3.42 b	1.20±0.22 b	10.63±2.44 a	96.14±13.84 a	6.38±1.04 b
经产母猪	≤17	42	14.28±2.70 a	1.27±0.13 b	10.57±2.13 a	93.85±12.51 a	7.01±0.20 a
Multiparous	(17, 20)	209	14.55±3.24 a	1.32±0.10 a	10.58±2.62 a	95.15±11.65 a	6.82±0.28 b
sows	[20, 22]	254	13.97±2.98 a	1.31±0.13 a	10.22±2.41 a	95.38±12.23 a	6.82±0.48 b
	>22	46	14.66±2.03 a	1.33±0.07 a	10.59±1.98 a	95.64±11.74 a	6.85±0.36 b

类别 Sort	总产仔数 Total number of born	产活仔数 Number of born alive	健仔数 Number of healthy born	初生窝重 Litter birth weight	初生重 Average piglet birth weight	断奶数 Number of weaned piglets	断奶率 Weaning survival rate	断奶重 Weaning weight of piglets
初产母猪 Primiparous sows	-0.070	-0.062	-0.044	-0.121^**	-0.126^**	0.013	0.074	-0.167^**
经产母猪 Multiparous sows	-0.078	-0.093^*	-0.085	-0.096^*	-0.430	-0.053	0.042	-0.060

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