Whether it be nutrition, disease, weaning age, diagnostics or breeding, the common theme that affects them all, including sow longevity, is management.
Case Study No. 1
I was called to a farrow-to-finish operation that was converted to a breed-to-wean facility. The finishing unit had been converted to a pen gestation barn, housing 600 sows and gilts. Nursery rooms were converted to farrowing.
Gilts fitting the disease profile of the herd were purchased. They were exposed daily to boars during isolation and acclimation (I/A), then were added to the breeding herd.
Gilts were fed gestation feed during I/A, and weighed about 260 lb. when added to the herd.
The primary complaint was gilts had trouble farrowing and produced small litters.
In reviewing gilt management, it was apparent gilts were too young and small when bred. Many were culled due to poor reproductive performance.
To solve this problem, several management changes were made.
First, gilts were placed on a gilt developer ration during the I/A period to ensure adequate growth prior to breeding. Gilts need to be at least 8 months of age and weighing 280-300 lb. before being bred.
Second, gilts were housed in separate pens to ensure adequate feed intake during gestation. This helped eliminate the “boss sow” scenario. Heavier gilts at breeding provide a positive impact on sow longevity.
With these improvements, average parity increased from 2.8 to 4.8.
It is also crucial to supply adequate water to these young animals. Water is very important, especially in lactation, to maintain good milk production and body condition. It is without a doubt the cheapest and most important nutrient we can supply, but is all too often overlooked.
Case Study No. 2
I was called to a 1,200-sow, breed-to-wean facility experiencing poor reproductive performance.
Farrowing rates based on PigCHAMP records averaged 80%. But the adjusted farrowing rate was as low as 60%. Adjusted farrowing rate refers to the farrowing rate as a result of non-reproductive problems.
The herd has been positive for the porcine reproductive and respiratory syndrome (PRRS) virus since its population three years ago.
Breeding/gestation sows are housed in a double-curtain-sided, totally slotted barn with individual sow stalls.
The overall body condition score of the herd was 2.7 on a scale of 1-5, with 1 being thin and 5 being fat.
Gestating sows were being fed 5 lb./ day. The sows in lactation were on full feed, but remained in poor condition. The breed-to-wean interval averaged 14 days for sows.
All of these factors resulted in a high cull rate, an often-depleted gilt pool and a crowded breeding area. Temperature in the gestation barn was kept at about 65° F.
The vaccination protocol was reviewed and found to be adequate.
The off-site nurseries and finishers were performing well.
Serological diagnostics were completed and appeared normal.
The manager stated sow condition improved somewhat in summer, but it was a constant battle to maintain good sow condition in winter.
Equipment failure on the ventilation system was common. Sows often seemed chilled and irritable.
Room temperatures were similar throughout the gestation building, except at the floor level, where temperatures were 6-8 degrees cooler.
The first step in resolving this issue was to increase feed intake. Next, room temperature was increased. The ambient temperature (the actual temperature the animal feels) was much lower than the actual room temperature. This was due to ventilation rates and the cooler concrete upon which sows and gilts laid. Chilling increased energy demands.
Since the changes were made, sow herd body condition has improved greatly and reproductive performance is back to normal.
Case Study No. 3
I visited a 250-sow, farrow-to-finish operation experiencing several “downer” sows. Many of the sows had abrasions below their hocks and knees. Overall sow condition was good. The producer maintained a closed herd and bred using artificial insemination.
Sows were housed in older barns in pens of 15-20 head. Concrete flooring sloped to a 4-ft. flush gutter. Floors were often wet and slippery.
Several replacement gilts selected from the finisher exhibited conformation problems, including “bucked” knees, rear legs with a drop in pasterns and “sickle” hocks. These gilts had a hard time maneuvering even on dry floors.
Instead of trying to remodel the facilities, this producer chose to change genetics, purchasing replacements from an outside breeding stock source.
The herd was rolled over within one year and production parameters improved significantly.