Black soldier fly larvae meal and fat as a replacement for soybeans in organic broiler diets: effects on performance, body N retention, carcase and meat quality

1. Due to the increasing global demand for more sustainably produced animal protein, there is an intensive search for feeds to replace soybeans. Black soldier fly larvae (BSFL) appear to have great potential for replacing soybeans in poultry diets. The main objective of this study was to determine if the nutritional value of BSFL is superior to soybeans when feeding organic broilers, since smaller amounts of BSFL could replace the soybean content in the feed, thus saving even more resources.2. Eighty Hubbard S757, a slow growing organic broiler type, were fattened for 63 d, spending the last 49 d on one of five diets. Two soybean cake- and soybean oil-based diets (SS, SS-) were compared with three diets based on partially defatted BSFL meal and BSFL fat from two origins (AA-, AB-, BB-). Different from diet SS, diets SS-, AA-, AB-and BB- were designed with approximately 20% less lysine and methionine. Growth (n = 16), metabolisability, body nitrogen retention, carcase and meat quality (n = 8) were evaluated.3. Broilers of the insect-based feeding groups, AA- and AB-, grew similarly well compared to those of group SS. They also retained more nitrogen in the body than those fed BB- and SS-. Breast meat yield was higher with AA- and AB- than with BB- and SS-, but still lower than with SS. Dietary variations in physicochemical meat quality were of low practical relevance. Diet BB- resulted in a more yellow skin and meat. The fatty acid profile of the breast meat lipids reflected the high lauric acid proportion of the BSFL lipids, resulting in up to 80 times higher proportions than when feeding the soybean-based diets.4. The results indicate that high-quality BSFL, depending on their origin, may indeed be superior to soybean protein, but that the meat lipids from BSFL-fed broilers can contain significant amounts of lauric acid, which, from a human nutrition perspective, could have a negative impact on meat quality.

Black soldier fly larvae meal and fat can completely replace soybean cake and oil in diets for laying hens

Currently, there is a great interest in finding alternative protein and energy sources to replace soybean-based feeds in poultry diets. The main objective of the present study was to completely replace soybean in layer diets with defatted meal and fat from black soldier fly larvae without adverse effects. For this purpose, 5 × 10 Lohmann Brown Classic hens were fed either a soybean-based diet or diets based on defatted black soldier fly larvae meal and fat from 2 producers (1 commercial, 1 small-scale) operating with different rearing substrates, temperatures, and larvae processing methods (10 hens/diet). The data obtained included nutrient composition of larvae meals and diets, amino acid digestibility (6 hens/diet), and metabolizability, performance and egg quality (all 10 hens/diet). In addition, the acceptance of the 4 larvae-based diets was tested against the soybean-based diet in a 6-day choice feeding situation (10 hens/treatment). The nutritional value of the larvae-based diets was equivalent to the soybean-based diet in hens with a laying performance of 98%. Although average feed intake was not significantly different over the 7 experimental weeks, the diets based on larvae feeds from the small-scale production appeared to be slightly less accepted in a choice situation than the soy-based diet and those with larvae from commercial origin. This was more likely the effect of the larvae fat rather than that of the larvae protein meal. In addition, the commercial larvae material was superior to that from the small-scale production concerning supply with digestible sulfur-containing amino acids (548 vs. 511 mg/day) and lysine (792 vs. 693 mg/day), egg weight (67 vs. 63 g), daily egg mass (66 vs. 61 g/day) and, in tendency, feed efficiency. The results indicate that soybean-based feeds can be replaced completely by black soldier fly meal and fat in diets of high-performing layers. However, because of nutritional differences between the larvae materials of different origin the quality of the larvae has to be closely monitored before being used.

Are dual-purpose and male layer chickens more resilient against a low-protein-low-soybean diet than slow-growing broilers?

1. Although fattening dual-purpose types or male layer hybrid chickens appears more ethical than the common practice of culling day-old male layer chicks, the lower feed efficiency of these birds raises concerns. Replacing feed ingredients that compete with food production by those of lower value for human nutrition would be beneficial.2. Lohmann Dual (LD), a modern dual-purpose type, Lohmann Brown (LB), a male layer hybrid, and Hubbard JA 957 (HU), a slow-growing broiler type, were fattened for nine weeks on two diets (control or -20% crude protein; n = 6 × 12 birds). Growth, carcass and meat quality were analysed.3. Growth performance of HU exceeded that of LD and especially of LB. The growth depression caused by the low-protein diet fed to LD (-7%) was only half of that found in HU (-13%). The LD fed the control diet had the same feed efficiency as the HU fed the low-protein diet. Even the LB had a lower performance and feed efficiency with the low-protein diet in growth. There was a gradient in carcass properties (weight, dressing percentage, breast meat yield, breast proportion and breast angle) from HU to LD to LB, with some additional adverse effects of the low-protein diet especially in HU. There were some breed differences in fatty acid profile in the intramuscular fat.4. In conclusion, the dual-purpose type used complied with regulations for Swiss organic poultry systems in terms of growth rate and was found to respond less when fed a low-protein diet than the slow-growing broiler type. The LB males were inferior in all growth and carcass quality traits. Future studies need to determine the exact protein and amino acid requirements of dual-purpose and layer hybrid chickens and the economic feasibility of the systems, especially for organic farming.

Meat and carcass quality of Dexter cattle compared with that of suckler, Charolais-cross calves: a preliminary study

Tenderness, flavour and colour are the most important quality traits of beef that are influenced by breed and age. Suckler calves (SC) produce very tender, high-quality meat. Extensively growing, small-framed breeds are known for high-quality beef, but information about the particularly small Dexter cattle (D) is yet unavailable. Eight D and seven Charolais-crossbreed SC were kept for 11 weeks on alpine pastures to be able to compare their meat quality. The SC were kept with their dams. The animals of the two breeds were slaughtered at different ages (D: 15 months and SC: 7 months) consistent with their respective production system conventions. Although this meant that age and breed effects were confounded, slaughter took place at the same carcass fatness score, thereby avoiding a confounding effect on meat quality. Quality of the carcass and of two muscles (M. biceps femoris, M. longissimus thoracis) was analysed. Despite being older, D had lower body and carcass weights, dressing percentage and bodyweight gains than SC. Dexter meat was darker than SC meat. Shear force did not differ between D and SC in the M. longissimus thoracis but was higher in the M. biceps femoris from D than from SC. Sensory analysis by a trained panel demonstrated an overall preference for D meat, associated with more favourable flavour and juiciness. Tenderness was not rated differently. Despite the unfavourable darker colour of D compared with SC meat, its characteristic flavour might attract consumers in a high-price niche market. For a more comprehensive characterisation, sensory evaluation of additional muscles is required. Additional measurements on a larger number of animals and muscles are required.

Swiss consumers' willingness to pay and attitudes regarding dual-purpose poultry and eggs

Chick culling is an efficient and cost-effective method in modern poultry farming, but it raises ethical concerns. Dual-purpose poultry (DP), in which males are fattened and females are used for egg production, is currently the most realistic alternative to culling, as in ovo sexing is not yet viable for practical application. Consumers' acceptance of DP products and their willingness to pay (WTP) for them have not been studied yet, and we expect that both aspects are closely related to the acceptance of and WTP for products from systems claiming beyond-conventional animal welfare, such as organic products. Results from a survey conducted among 402 consumers at 8 Swiss supermarkets revealed that the practice of chick culling was largely unknown (75% of respondents). Generally, respondents' knowledge about poultry production was low. The DP alternative was preferred to chick culling, but no preference emerged between DP and in ovo sexing. Furthermore, the WTP for DP products was proportionally lower for chicken than for eggs, probably because of the different price elasticity between these products. A regression analysis was used to determine the factors influencing consumers' WTP for DP products. Consumers' WTP was positively related to knowledge about poultry production, habits tied to purchasing organic or free-range poultry products, and familiarity with DP products. Therefore, a combination of the DP alternative with an organic label is recommended.