The last issue of Progressive Pork included a report on a three-year study by the University of Illinois to look at options for managing wean-to-finish facilities. The topic continues to be something Farmweld is watching closely. Here are results from another study concluded at the University of Nebraska.

			Dr. Michael Brumm

Scientists at the University of Nebraska found that during the nursery phase, pigs raised in single-stocked, wean-to-finish facilities perform better than pigs raised in double-stocked, wean-to-finish facilities or in a traditional system where pigs are started in a nursery, then moved to a finishing facility. Dr. Michael C. Brumm led the research, which compared the following specific management systems over three consecutive trials:

1. Wean-to-finish (WF).Pigs were weaned into grow-finish pens and stocked at 7.5 sq. ft. (.70 m²)/pig from weaning to slaughtering.
    
2. Double-stock/wean-to-finish. (DS/WF) Pigs were weaned into grow-finish pens at twice the rate (3.75 sq. ft./pig or .35m²/pig) of the first group. At eight weeks after weaning, pigs were randomly sorted into two groups. One group remained in the same pen and the other group was relocated to another empty pen in the same facility. All the pigs were then raised to slaughter at a 7.5 sq. ft./pig (.70m²/pig).
    
3. Pigs were weaned into a nursery and stocked at a rate of 3.75 sq. ft./pig (.35 m²/pig) until eight weeks. They were then moved to the finisher (same facility as pigs in first and second group) and raised to slaughter at 7.5 sq. ft./pig (.70 m²/pig).

The research was conducted at Nebraska’s Haskell Ag Laboratory near Concord. The grow-finish facility is a double-wide, naturally ventilated building with full cement slatting. The nursery is mechanically ventilated with unvented heaters and woven wire flooring. There were 15 pigs per pen for the WF and NF treatments and 30 pigs per pen in the DS/WF group for the first eight weeks.

There was one, two-hole Farmweld Jumbo Feeder and one Farmweld DRIK-O-MAT® Water Cup for every 15 pigs. Heat lamps were used as supplemental heat for the WF and the DS/WF groups and comfort mats were used for all three groups. A commercially-available nursery diet sequence was used to 40 pounds (18.2 kg) of bodyweight based on a pre-planned feed budget. Grow-finish rations were corn-soybean based with 2% added fat, formulated according to lysine requirements for five feeding stages.

All pigs were weaned at 17 days weighing an average of 11.2 lbs. (5.1 kg). Each were barrow offspring of PIC genetic crosses. In Trials 1 and 2, an outbreak of gut edema occurred during weeks two through four. It was most severe in the WF and DS/WF groups. In Trial 1, only the WF and the DS/WF pigs were treated. In Trial 2, all pigs were treated. No gut edema occurred in Trial 3 so pigs were not treated. Pigs in Trial 1 and 2 also had health challenges due to complications associated with PRRS.

Despite the health concerns mentioned above, the WF pigs performed better than the DS/WF or NF pigs during the nursery phase. This was due to greater feed intake with faster daily gains. According to Brumm, the lower performance of the DS/WF group compared to the WF group was likely due to the increased number of pigs per pen. There is good evidence that increasing group sizes (in the range of group sizes studied) results in a decrease in daily feed consumption and gain. The researchers also noted that it is possible that the industry is seeing improvements in performance in wean-to-finish units compared to conventional nurseries because many conventional nurseries offer inadequate space and feeder size for heavier pigs now common in nurseries. Performance did not differ among the three groups during the grow-finish period.

Impact of wean-to-finish regimen on pig performance

 

	WF	DS/WF	NF
No. pens	12	12	12
Weaning wt. lb.	11.2 (5.1 kg)	11.2 (5.1 kg)	11.2 (5.1 kg)
56 day wt. lb.	63.1 (28.7 kg)	59.2 (26.9 kg)	60.9 (27.68 kg)
Ave. Daily Gain, lb.	0.92 (.42 kg)	0.86 (.39 kg)	0.89 (.40 kg)
Ave. Daily Intake, lb.	1.53 (.70 kg)	1.42 (.65 kg)	1.47 (.67 kg)
Feed:Gain	1.66	1.66	1.64

Key                        

WF= Wean-to-Finish

DS/WF = Double Stocked, Wean-to-finish

NF= Nursery Moved to Wean-to-Finish

DS/WF - S= Double Stocked, Wean-to-finish - Pigs remaining in same pen throughout trial

DS/WF - M= Double Stocked, Wean-to-finish -- Pigs moved to new pen in same facility