The cost of feed for almost all raw materials has skyrocketed, so many feed and pig farms are seriously considering how to reduce the cost of feed per kilogram of gain. Depending on the market and production system, swine producers may consider different options, writes swine nutrition expert Dr. Francesc Molist.
1. Reduce slaughter weight
The feed-to-weight ratio increased linearly with the increase in body weight/day age. This is because maintenance requirements also increase as body weight increases; in finishing pigs (after 80 kg body weight), back fat thickness increases faster than muscle deposition, and when more fat is deposited, weight gain decreases. Therefore, reducing the final slaughter weight from 125-130 kg to 115 kg will significantly improve the feed conversion ratio and reduce production costs given the current higher feed costs.
Compared to sows, boars have a much higher feed-to-weight ratio due to their lower lean daily gain and higher feed intake (ad libitum). Ideally, for boars, feed intake should be limited to 80% of ad libitum for pigs over 75 kg body weight. This type of feed restriction can be achieved by reducing the amount fed to the boar, or by reducing the net energy of the feed and significantly increasing the fermentable fiber content to increase the GI fill rate. Therefore, specific boar feeds can be formulated with lower SID lysine and net energy compared to gilts.
From a breeding industry perspective (better average daily gain (ADG) and feed-to-weight ratio + no castration/injection) and meat processing industry perspective (higher lean meat percentage), feeding complete Boars are more beneficial. From a meat processing industry perspective, the downside is the risk associated with boar taint. About 4-8% of boars can be identified with higher levels of boar odor, but it can also occur in sows.
Another solution to boar taint is immunocastration. Acceptance of the immunocastration vaccine will depend on the meatpacking industry and the costs associated with this approach (two vaccinations are required). In conclusion, raising (whole) boars and sows can significantly reduce the cost per kilogram of pork, if the market allows it, given the current feed price hikes.
3. Multi-stage feeding
With the increase of feed-to-weight ratio, most of the feed is consumed in the fattening stage (from 80 kg to slaughter). From this point of view, feeding different stages (eg 2-stage or multi-stage fertilisers) can help reduce feed costs as nutrient concentrations can also be reduced in later stages. As mentioned earlier, during the finishing phase, pigs have a higher feed intake and grow primarily fat rather than muscle. Therefore, this opens up some possibilities for reducing feed net energy and SID lysine levels in finishing pigs to save some feed costs.
Depending on the market, feed formulation will be one of the main drivers of feed costs, in addition to reducing net energy and SID lysine in the finishing stage. Strict attention to nutrient density, crude protein and amino acid levels of pigs and the use of attractively priced feeds can help reduce feed costs per kg body weight.
Doing this requires controlling for changes in feed analysis and data, reducing safety thresholds in feed, which are often associated with higher costs. By carefully monitoring the crude protein content of feeds (protein-enriched feeds and grains), reducing variability in the crude protein content of finished feeds will help control feed costs (by enabling a lower "safety factor") and lead to more consistent production performance.
A large part of the cost of feed comes from feed additives. Therefore, a careful review of which feed additives are effective and at what stage (feed formulation) is recommended. In addition, the mixed use of different feed additives with similar mechanisms of action in the same feed formulation may be questioned. The Schothorst feed study showed that omitting the vitamin and mineral premix in the last month before slaughter did not reduce performance.
Fat-soluble vitamins (A, D and E) are the most expensive part of the premix (up to 50%), they accumulate in the body (liver) during the growing period and are less prone to deficiency than water-soluble vitamins and trace minerals. Since vitamin and mineral premix costs typically account for around 4% of feed costs, it is easy to save 1% of feed costs in the finisher feed. On the other hand, feed additives that improve gut health or nutrient utilization efficiency can help reduce feed costs per kilogram of gain, albeit at higher feed prices.
6. Phosphorus content and phytase
Phosphorus is the most expensive inorganic mineral additive in pig and sow feed, accounting for 0.5-1.0% of feed cost. Thanks to regulations to reduce phosphorus emissions, the (digestible) phosphorus content in the EU has been reduced compared to Asian countries without a reduction in production performance. In addition, newer phytases release phytate-bound (plant) phosphorus more efficiently, reducing feed costs.
Compared with ordinary feed, feed pelleting reduces feed waste and improves the utilization rate of nutrients. Generally, an increase in feed conversion ratio (a 1-2% reduction in feed ratio) can easily offset the cost of pelleting. However, grinding too finely can be detrimental to gut health.
In conclusion, the possibility of reducing the cost of feed per kg of weight gain was explored. There are several possibilities in the farming industry that require changes in pig farms and slaughterhouses. In feed formulations, there is always a risk of lowering the "safety threshold" in terms of production performance. Finally, an economic calculation of all opportunities is required.