Pig production is a competitive business and the way to win is usually to produce more pigmeat at lower cost. Independent consultant John Richardson, of Production Performance Services Ltd, discusses how better farrowing management can improve pig unit output.
Pigs reared/sow/year remains a principle factor in determining profitability on pig units, and Table 1 (below) shows how Great Britain’s indoor producers compare with two of the EU’s major intra-community traders/suppliers of pigmeat. Pre-weaning piglet mortality is stubbornly static for most GB herds at between 12 and 14%, with most of the improvement in pigs reared/litter coming from an increase in overall numbers born. Even so, our herds are still deficient by two to three pigs/litter compared to key competitors – an area that might be resolved by selecting more prolific genotypes.
Farrowing is the culmination of one phase of production – pregnancy; followed by the start of another – pig rearing and finishing. On too many farms farrowing simply ‘occurs’, rather than being strategically managed. The results are often variable still birth rates, unnecessarily high pre-weaning mortality and compromised piglet growth.
The birth process is potentially a high-risk event for most mammals, but perhaps more so for piglets, being 130 to 200 times smaller than their mother with the risk of overlying being highly significant. Low body fat reserves, no hair cover and a relatively large surface area mean that chilling, lethargy and failure to suckle life-supporting colostrum can soon quickly and effectively reduce survival rates.
Being born in a litter of increasingly larger numbers also exacerbates the risk of stillbirths (see Table 1) and oxygen deprivation, notably in the latter 20% of pigs born. These piglets will be slower to suckle, less competitive at the udder and more susceptible to dying within the first five days of life. Mother Nature is quite cruel – being driven by the need to naturally select the most vigorous pigs, whereas the pig producer should aim to intervene to minimise this natural process so maximising every pigs’ chance of survival – and farm output.
Keeping the herd relatively young by using a performance-based culling regime to oust older, poorer-performing sows is often under utilised when managing the breeding herd. Table 2 shows how productivity wanes after parity five. Based on this data, which relates to 50,000 sows in 97 indoor herds, there is a strong case to cull all (with maybe the exception of very high performing individuals) following parity five.
Farrowing supervision
As already identified, farrowing and the first 24 hours after birth is the most critical time for staff to influence piglet survival. However, on many units intervention and input during this crucial time is below par due either to a lack of skills or time available. Perhaps, if newly born pigs were observed as being worth £30 each, then the focus might be different.
Many high-performance units (27+ pigs/sow/year) now induce and supervise at least 75% of their farrowings. A few are also operating 24-hour supervision during this period because they see a worthwhile improvement in both the number and quality of pigs reared.
Table 3 shows the results achieved in a herd that previously didn’t induce or routinely supervise farrowings, relative to a subsequent three-month period when the majority of farrowings were induced and supervised. The results from inducing sows to farrow was an extra pig reared per litter, equivalent to an extra 2.35 pigs/sow/year reared. This puts the unit well on target to achieve BPEX’s Breed+3 target and has proved well worth the extra investment in both time and money.In the September issue, I’ll look at cross-fostering and other alternatives to increase the number of pigs reared per litter.
Basic rules for inducing and supervising farrowing:
- Know the average gestation length for your herd (92% of sows will farrow naturally between 113-117 days of pregnancy).
- Only induce sows that are within 1-2 days of the average gestation period.
- Check the ear number and stage of mammary development of each sow prior to inducing with a prostaglandin product.
- Use a mild-acting prostaglandin such as Planate, giving 2ml intramuscularly with a 38-40mm x 16-18 gauge needle. Ideally administer between 07:00-08:00 so that sows farrow during the next working day.
- Check all sows for imminent farrowing before leaving the unit the day before they are due to farrow following the inducement. Place additional heat lamps and shredded paper at the sides and rear of any sows that are likely to give birth. The presence of colostrum in teats is a good indication that farrowing is imminent.
- On the day of farrowing, first check all sows to see if any have started the birth process. For those that have farrowed, ensure that no pigs are chilled and all are suckling. Record the time of the last pig born and also the volume of placenta expelled.
- As piglets are born, dry them off using shredded paper or paper towels; place them in a heated tub for 30-40 minutes, then put them onto the udder. The oxytocin ‘surge’ created by them suckling will stimulate further uterine contractions resulting in more pigs being born. Repeat this procedure with all newly born piglets. Assisting any smaller pigs to suckle during their first few hours of life is very worthwhile.
- Piglets suckling for an hour or so can be marked and placed either in a heated creep area or in the tub. This allows smaller or later born piglets better access to the more productive front teats.
- If a sow has not produced a pig for 30 minutes or so, but continues to strain, intervention is worthwhile. An internal examination using a hand/arm covered with a plastic sleeve and obstetric gel can help free a mal-presented piglet. If sows are not straining and there are signs that she has not finished farrowing then a 0.5-1.0ml injection of Oxytocin-S, given intramuscularly, can stimulate contractions. This hormone treatment must not be overdosed, so must not be given any more frequently than at 45 minute intervals. Giving a 1.0ml dose of Oxytocin-S can also help expel any residual pigs and also the placenta, and can be useful if a sow has not ‘cleansed’, but is suspected of being near the end of farrowing.
- Allow all piglets to suckle their birth-sow for at least six hours to gain specific maternal antibodies before considering any cross-fostering. Check the sow’s teats to ensure none are damaged and all are functional. Do give assistance to any small pigs to suckle the all-important life-giving colostrum.