Club and Show Pig Seminar

1
What Should I Do When the Weaned Sows Do Not
Cycle?

• Donald G. Levis, PhD
• Ohio Pork Industry Center
• The Ohio State University
• 122C Animal Sciences Building
• Columbus, OH 43210-1095
• Telephone [phone]
• Cell 614 404 7248
• E-mail levis.7_at_osu.edu
• Web site http//porkinfo.osu.edu

2
The use of hormone therapy does not absolutely
guarantee that sows and gilts will cycle at a
predetermined time!
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Relationship between age of semen and hormone
therapy
268
244
220
196
Accumulated age of sperm cells, hrs
172
148
124
100
76
(11 days)
6 d
52
28
Semen collected
Semen arrives
Estrus
PG 600
Expect estrus
4.76 days
Weaned
28 h
24
24
24
24
24
24
24
24
24
24
4
To help increase your odds of having sows or
gilts in estrus at a pre-determined time, you
need to use hormone therapy in advance of the
arrival of purchased semen!
5
Use of PG600 at time of weaning (P1 sows)
Swine Health Production 6171-173, 1998.
(Nov to Mar matings)
6
Use of PG600 at time of weaning (P1 sows)Farm 2
Aug to Dec matings
Swine Health Production 651-55, 1998.
7
Use of PG600 at time of weaning (P1 sows)Farm 4
Aug to Dec matings
Swine Health Production 651-55, 1998.
8
Use of PG600 at time of weaningJun to Sep
matings (Avg Parity 4.6)
Theriogenology 49823-828, 1998.
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Short-term immediate remedy

• Increase exposure to mature boars
• Physical contact
• Twice per day
• Use smelly, aggressive boars
• Maximize volume of feed offered after weaning
• Group-house problem sows

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Long-term preventative remedies

• Appropriate management of feed intake during
  gestation

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Effect of gestation feed intake on voluntary
lactation feed intake of P1 sows
J. Anim. Sci. 751845-1852, 1997.
12
Percentage of P1 sows returning to estrus after
weaning
J. Anim. Sci. 751845-1852, 1997.
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Long-term preventative remedies

• Appropriate management of feed intake during
  lactation
• Feed intake during the first 7 to 10 days of
  lactation is critical!
• ?Establishment of reproductive hormones start to
  occur

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Effect of lactation feed intake on
weaning-to-estrous interval (P1 sows)
WEI
7.8 d
15.5 d
14.6 d
21.2 d
25.0 d
29.8 d
Anim. Prod. 42119-125, 1986.
15
Effect of lactation feed intake on
weaning-to-estrous interval (P1 sows)
a H high energy diet (16.5 Mcal ME/d) L low
energy diet (6.5 Mcal ME/d) b WEI is
weaning-to-estrous interval (days)
J. Anim. Sci. 741036-1046, 1996.
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Effect of lactation feed intake on
weaning-to-estrous interval (P1 sows)
Animal Reproduction Science 52153-163, 1998.
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Long-term preventative remedies

• Appropriate management of the ambient temperature
  in the farrowing facility during lactation

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Effect of ambient temperature on lactation feed
intake and body weight loss
12.5
11.9
10.8
9.9
6.8
J. Anim. Sci. 772124-2134, 1999.
19
Effect of backfat depth at weaning on
weaning-to-estrous interval
Animal Production 57437-445, 1993.
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The End
We sincerely appreciate your taking time to
attend this seminar!