The growing use of artificial insemination (AI) has provided tremendous opportunities for improvements in meat quality issues, growth parameters and health issues.
AI also opens the door for numerous challenges and potential problem areas as we take one of Mother Nature's jobs into our own gloved hands.
Nearly 75% of our clients use AI. With these clients, we have grown and learned from the challenges and know which areas to monitor.
Case Study No. 1 The manager of a custom-collect, 50-head boar stud called complaining that boars suddenly didn't want to mount, weren't aggressive and showed poor signs of libido. This affected 10% of the boars.
At the stud, boars didn't appear ill. Further questioning revealed the farm had received a new batch of feed the week prior from a new supplier. The ration was corn/soy-based, 19% crude protein and 7% fat. The feed appeared normal.
The feed manufacturer was contacted to double check the product delivered. Their investigation revealed the wrong nutrient inclusion rates had been used, and the ration was actually 13% crude protein and 2% fat. The manufacturer immediately replaced the existing rations with the correct diet. Boar libido returned quickly.
Open communication lines and expediency helped prevent this case from becoming more serious. It didn't affect recipients of the semen.
Case Study No. 2 On a 900-sow farm, a white, pus-like substance was discharging from the vulvas of females 11-14 days after being bred by AI.
Breeding techniques appeared to be good on the farm. The manager was well acquainted with AI and didn't appear to be breeding animals too late in the estrous cycle. Cleanliness at breeding time was good. In fact, the breeding manager was spraying the vulva with disinfectant and wiping with a paper towel prior to insertion of the spirette. The disposable spirette was discarded after one mating.
The breeding manager also had implemented a 15-cc. injection of penicillin to all weaned sows. The herd also got 500 g. of chlortetracycline in the feed for three weeks with no affect on the discharge.
Semen was purchased from a custom-collect boar stud. It was collected during the evening and delivered to the farm via carrier the following morning. During my visit, we examined one- and four-day-old semen on the farm's microscope. The warmed, one-day-old semen appeared good. The warmed, four-day-old semen showed a high percentage of dead sperm cells and had an off smell.
Tubes of one-day-old semen, four-day-old semen and vaginal swabs from three discharging sows were submitted to the University of Missouri Diagnostic Laboratory. Bacteriology cultured a specific bacteria from the semen and from the vaginal swabs. The bacteria was resistant to typical antibiotics put in semen extenders including gentamycin sulfate, spectinomycin, penicillin and neomycin sulfate.
We concluded the stud had a resistant bacteria that was being passed through the semen to the sows, creating an abnormally high level of discharging sows.
The sow farm was already preparing to switch boar studs for genetic purposes. After this diagnosis, they switched immediately. The response to a different semen source was dramatic. Discharges ceased and conception rates jumped up by 10-15%.
This case emphasizes the importance of checking semen daily before use and also maintaining open communication lines with the stud.
Case Study No. 3 On a monthly herd visit to a 3,500-sow farm, we discussed consistently low farrowing rates. The unit weans at 17 days, and sows are placed in crates for breeding. Sows are moved within three days post-breeding to pens of 25-30 head.
The unit was receiving semen via overnight delivery on Tuesdays and Fridays. Older semen, collected on the previous Thursday was still being used the following Tuesday and sometimes Wednesday. Thus, some 5- to 6-day-old day semen was routinely being used. The breeding manager said the old semen was used primarily for first mating. Even though semen was extended in a seven-day extender, most experts agree fresher is better, and semen less than 72 hours old is best.
An arrangement was made with the boar stud for same-day delivery and for the unit to discard any old semen when the fresh semen arrived. Results since using fresher semen have been dramatic. Conception rates for the fourth quarter of 1999 were approximately 70%. Conception rates for the first quarter of 2000 were 83.5%.
We must constantly be aware of all the processes involved in AI and continually monitor management practices to prevent serious economic challenges.