Pig and poultry production | Tasty snacks for livestock

• Insect protein is a high-quality protein in feed and can replace soybean and fish meal in pig and poultry production.
• Insects can be farmed as a regional and sustainable circular economy.
• A high degree of automation reduces the workload, especially in insect growing.
• Feeding insect protein increases animal welfare for pigs and poultry. 
   

Of the more than 2000 edible insect species, only a few are suited for industrial farming, since insects are difficult to domesticate. One of the most promising species is the black soldier fly (Hermetia illucens).

Since the Commission Regulation (EU) 2021/1372 of 17 August 2021 amending Annex IV to Regulation (EC) No. 999/2001 came into effect at the beginning of September 2021, adding specific processed animal proteins (PAPs) to animal feed is legally permitted once more. This includes, among others, PAPs of beneficial insects.

The Commission decision was one of the most decisive legal prerequisites for starting professional insect farming. In the past, insect larvae have already been used as hypoallergenic and sustainable pet food.

In contrast to pig and poultry production, feeding animal proteins to ruminants continues to be forbidden in the EU, as a consequence of the BSE crisis.

Livestock need proteins in their feed so they can reach their full potential. According to the Federal Statistical Office of Germany, Germany imported nearly 3.6 million tons of soy in 2021, mainly from South America. Most of the imported soy is used as feed in livestock production.

Studies have shown that the amino acid profile of the black soldier fly larvae (BSFL) is very similar to that of the soy bean, i.e. BSFL are well-suited for pigs, poultry and fish.

In 2018, researchers found that “in terms of nutritional physiology, the black soldier fly insect meal is suited to replace a substantial share of soybean meal in the diet of broilers and finishing pigs” (source: 08/01/2018 – M. Sc. Susanne Velten and Prof. Dr. Frank Liebert, University of Göttingen).

Table 1 compares the amino acid contents of soybean meal (SBM) with those of the black soldier fly.

Some amino acids of the larvae meal, such as cysteine and arginine, show deficits compared to soybean meal (Fig. 1).These deficits can be compensated for by synthetic amino acid additives. For methionine, however, which is the most limiting amino acid for poultry diets and important for a good egg weight, the shares are nearly identical.

Lysine is an amino acid that is especially important for body mass and muscle protein. This means that an additive is required to reach the ideal lysine share in feed. Feed producers can very easily adjust their recipes accordingly.

The nutritional basis for insects can be very varied, since insects do not make high demands on their feed. However, insects are classified as livestock, which means that in Germany, the Order on the Protection of Animals and the Keeping of Production Animals (Tierschutz-Nutztierhaltungsverordnung) applies. Feeding insects kitchen waste, leftovers or other waste substrates is therefore currently not permitted.

Only authorised feedstuffs such as wheat bran, rye groats or maize silage are allowed. This reduces the competitiveness of larvae meal compared to imported soy. In the interest of sustainability and a circular economy, approving food waste as a substrate for insects would be a good idea.

The International Platform of Insects for Food and Feed (IPIFF) is asking the EU for more progress in this regard. According to the EU’s “Farm to Fork” strategy, “around six percent of the total EU emissions” can be attributed to food waste. Insect farmers can and are willing to help reduce these emissions. Only when real alternatives instead of just the approved feedstuffs can be used to feed insects will the “double protein conversion” end.

This new production branch would also benefit from the EU’s agricultural subsidies. Another point in favour of insects: in contrast to pig and poultry production, no medication is administered in the short growing period of just seven days.

Rearing and especially growing larvae is not rocket science. Technology used for livestock production also fits the requirements of insect farming. The system size can be scaled as needed and existing buildings, for example old livestock houses, can be reused.

For feed supply, a technology that has proven its worth in pig houses can be used for insects: computer-controlled liquid feeding systems (with some important adjustments) that come with digital analysis options. It is important to know that the particles of wet feed for insects are just one to two millimetres large, i.e. much smaller than in pig feed.

The technology must also be adjusted so the farmer can use many different feed types very easily. Additionally, dry matter contents are much higher for insects.

The larvae increase their weight by the factor 250 (!) in the climate chambers within just one week, at a feed conversion ratio of 1 : 1.1 to 1.3. A well-proven climate computer controls temperature, humidity, air flow and heating. There are some important points to keep in mind here, because if temperature and especially ventilation are not correct, the larvae may not develop ideally. In the worst-case scenario, they will climb out of the crates.

Using a heat exchanger is recommended to recover up to 50 percent of the outgoing heat. Robots separate the fully-grown larvae from the substrate, the so-called frass. A robotic arm takes the crates, which are stacked on a pallet, and empties the larvae into a sieve.

The empty crates are immediately refilled with feed and young larvae and placed back on the pallet. The crates then again remain in the climate chamber for an entire week. 150 tonnes of larvae can be produced in each climate chamber per year. The sieved frass is a valuable organic fertiliser that can be used as soil conditioner or in biogas plants.

Insect farming becomes more efficient the more climate chambers are used.

The cost distribution shows that the second largest cost factor after costs for the larvae (45 percent) is the feed (33 percent). There is thus a savings potential which could be unlocked by expanding the range of permitted feed options.

Insects are part of the natural diet of wild animals. It does therefore not come as a surprise that studies of independent research facilities have already shown that insect protein has a positive influence on our domesticated livestock, including pigs and poultry.

A study by the Wageningen University (Kar et al., 2021) about gut health says that consuming insect meal leads to a rich gut microbiome and therefore to a “healthy gut” in finishing pigs. A study of the University of Guelph (Crosbie et al., 2020) analysing digestibility found that finishing pigs digest most of the amino acids in insect meal similarly or even better than soybean meal.

The Bingen Technical University showed in a feeding study (Schneider & Dusel 2023, unpublished) that a share of up to 7.5 percent of insect meal in the total portion of broiler feed caused no performance losses. Layers as well as pigs appreciate live larvae as a snack; the insects also serve as diversion, similarly to the natural environment. For layers, the use of live larvae can reduce occasionally occurring feather pecking.

Insect protein is a versatile alternative protein source in pig and poultry feed and pet food. Insects are easily digestible and have an amino acid profile that is similar to soybean meal. Insect farming can thus make an important contribution to sustainability and climate protection by reducing soy imports that are not sustainable.

For Germany’s agriculture industry, insect farming can be a worthwhile investment in space-saving protein production, considering the decreasing amount of agricultural areas. Investing in insects thus means investing in the future protein supply for our livestock and, as a consequence, also for humans.

Dipl.-Ing. agr. Janett Peschel, Big Dutchman

DGS magazine | 07/2023