The use of live insect larvae to improve sustainability and animal welfare in organic chicken production

It is known that worldwide meat consumption has drastically increased over the last decades, especially in developed countries. Indeed, recent studies show that animal-based proteins consumption increased on average from 61 g per capita per day in 1961 to 80 g per capita per day in 2011 (Sans et al.; 2015). This phenomenon is related to the rapid growth of global population, economic development of countries and urbanization (Godfray et al.; 2018). In fact, not only are countries getting richer (therefore increasing GDP and gaining access to foods that were once considered exclusive to the middle and upper class), but also meat is getting cheaper and quicker to produce (Sans et al.; 2015). Meat is now easier to produce mainly due to: 1) genetic selection of the animals: these animals are able to produce more in less time due to higher adaptability, quicker development and better feed conversion ratio (FCR) 2) selection of feed: due to the high requirements of farmed animals, nowadays feeds pre- sent high nutritional values and are especially high in proteins 3) innovative farming systems: thanks to the constant research, we can now increase the welfare of farmed animals, therefore increasing productivity (Brameld et al.; 2016). As stated before, meat consumption increased worldwide but some countries underwent strong economic transitions and are now consuming more meat than other countries. Among these, we can find Argentina, Australia, Brazil, Chile, China, New Zealand and U.S.A. The only exception to this trend is India, where most of the population prevalently consumes a vegetarian diet. This country doesn’t show any important change in meat consumption over the last decades(www.ourworldindata.org). The type of meat consumed changes across each country. On average, poultry and pork are the most consumed worldwide (www.fao.org). In 2018 FAO estimated that roughly 69 billion chickens were slaughtered for meat produc- tion. The countries with the highest poultry density are Brazil, China and U.S.A (www.fao.org). With this data overview, it is interesting to understand why poultry meat is largely consumed and why it is convenient to raise chickens for meat. It is well known that chickens underwent an important selection within the past decades. The same genetic stock can grow globally, under any type of husbandry conditions. Through the genetic selection, the chickens’ weight has dramatically increased, yet the FCR has de- creased (Brameld et al.; 2016). 2 Chickens specifically reared for meat are called broilers. These animals underwent a strong selection in order to reach market weight at a very young age as, broilers are slaughtered at 43 days of age, on average (Bianchi et al.; 2007). In 1985, broilers at 35 days of age required 3.22 kg of feed to reach a weight of 1.4 kg and had a FCR of 2.3. In 2010, broilers only required 3.66 kg of feed in order to reach a body weight of 2.44 kg at 35 days, with a FCR equal to 1.5 (Siegel et al.; 2014). In other words, modern broilers are able to produce more meat while consuming less feed. This development obviously comes with health implications since artificial selection led to several health and welfare problems. Broiler diseases may depend on their genetics and physiology. Moreover, also the farming condition can affect diseases development. Among the several diseases that affect broilers we can find: 1) Cardiovascular dysfunctions: broilers are selected to abnormally develop their breasts and thighs. The organs, on the other hand, do not grow proportionally to the targeted muscles. This incongruous ratio between energy-supplying and energy-consuming or- gans leads to various metabolic disorders, such as ascites and “sudden death syndrome” (Baghbanzadeh et al.; 2008). a) Ascites (picture 2) is characterized by myocardial hypertrophy and dilatation, abnor- mal liver function, pulmonary insufficiency, and hypoxemia (Luger et al.; 2003) b) SDS (“sudden death syndrome”) mainly affects fast-growing chickens. Suddenly the broiler, even though it appears to be healthy, flaps its wings, fallsto the side and dies. This all happens under a minute (Newberry et al.; 1987). In Europe this syndrome usually affects 3% of birds (Turner et al.; 2014). 2) Skeletal dysfunctions(picture 3): varus and valgus deformities, osteodystrophy, dyschon- droplasia and femoral head necrosis are common in broilers. These dysfunctions lead to a severe lameness in the chickens, inducing them to spend more time lying on the ground and sleeping. If the broilers spend too much time lying down, under the abnormal weight of their bodies, not only can they suffocate, but also, they will develop integument lesions (Juliani; 1998). 3) Integument lesions: these birds are often subjected to dermatitis (e.g.: hock burn, footpad lesions), hyperkeratosis and necrosis of the epidermis (picture 4). This is not only due to the poor blood circulation, but also due to the prolonged contact with the ammonia in the litter (Greene et al.; 1985). Another issue related to the production of poultry meat is its important environmental im- pact. Feeding poultry requires a huge quantity of feed and these animals annually excrete important amounts of nitrogen and phosphorus to the environment, which conditions the production sustainability of this chain (Andretta et al., 2021). Nevertheless, poultry produc- tion has been found to be relatively environmentally friendly compared to other livestock productions, such as that of cattle. (Leinonen et al., 2016). The environmental impact of poultry production can roughly be divided into feed production and transportation, housing emissions and manure emissions. One of the main critical aspects related to poultry production is the amount of feed necessary to grow these animals. These feeds are particularly high in proteins, in order to satisfy the high requirements of chickens. Poultry feeds are made of cereals and their by-products (e.g.: corn, wheat, corn gluten meal), vegetable protein meals (such as soybean meal), oils, vita- mins and minerals. The most important protein source in poultry feed is soybean, usually given as a meal. This ingredient is high in proteins, low in fibers and high in lysine and tryptophan (even if deficient in methionine). Soybean meal is relatively inexpensive com- pared to other protein sources, such as corn gluten meal. The main issue related to soybean isthat it has a strong impact on the environment, mainly due to the fact that in the past couple of decades some areas around the world (like South America and South Asia) have been converted from natural foreststo soya crops (Kastens et al.; 2017). Then this ingredient must be transported to the feed mills around the world (mainly Europe, America and Asia). The loss of ecosystem carbon storage as a consequence of such conversion was added to the carbon dioxide emissions, therefore to the global warming potential arising from this system (Leinonen et al; 2016). For what concerns the housing emissions, recent studies show an important difference in terms of emissions based on the type of housing system. Three systems were taken into consideration: standard (indoor), free range and organic. Studies show that less intensive poultry systems had higher environmental impacts compared to the more intensive ones (Leinonen et al; 2016) in such way: organic systems have higher contributions in terms of eutrophication potential and acidification potentials (due to the emissions of NH3 and N2O), but extensive poultry production can reduce the use of fossil fuels, fertilizers and has lower housing emissions (Leinonen et al.; 2016). Although organic systems show less manure in the litter, it still has an environmental impact. On average, a single broiler excretes 0,6kg of N and 0,1kg of P each year. The amount of N found in the uric acid, expresses as kg/year, is equal to 0,5 (Rotz; 2004). Usually, poultry manure is used as a fertilizer, although it must be 6 used with caution due to the high concentration of N, P and K. If used incorrectly, it could severely damage the crops and it could lead to the excessive eutrophication and acidification of the soil (Leinonen et al.; 2016). Despite what preceded, how could we possibly reduce the environmental impact of poultry meat production? Scientists all over the world are trying to find new farming strategies in order to produce high quality meat with a lower environmental impact. Genetic selections, as stated before, has improved the FCR of animals (chickens can now produce more while eating less feed, at a faster rate), but the main ingredients in feed cannot be totally substituted now. The main challenge nowadays is to find an appropriate substitute for soybean meal, which is known to be the least environmental-friendly ingredient. The purpose of the project POULTRYNSECT is to test the effects of live insect larvae on slow and medium-growing organic chickens to allow sustainable meat production and to improve animal welfare. Insect larvae are reared on organic food by-products and are used as feed ingredient and environmental enrichment for chickens

The use of live insect larvae to improve sustainability and animal welfare in organic chicken production

It is known that worldwide meat consumption has drastically increased over the last decades, especially in developed countries. Indeed, recent studies show that animal-based proteins consumption increased on average from 61 g per capita per day in 1961 to 80 g per capita per day in 2011 (Sans et al.; 2015). This phenomenon is related to the rapid growth of global population, economic development of countries and urbanization (Godfray et al.; 2018). In fact, not only are countries getting richer (therefore increasing GDP and gaining access to foods that were once considered exclusive to the middle and upper class), but also meat is getting cheaper and quicker to produce (Sans et al.; 2015). Meat is now easier to produce mainly due to: 1) genetic selection of the animals: these animals are able to produce more in less time due to higher adaptability, quicker development and better feed conversion ratio (FCR) 2) selection of feed: due to the high requirements of farmed animals, nowadays feeds pre- sent high nutritional values and are especially high in proteins 3) innovative farming systems: thanks to the constant research, we can now increase the welfare of farmed animals, therefore increasing productivity (Brameld et al.; 2016). As stated before, meat consumption increased worldwide but some countries underwent strong economic transitions and are now consuming more meat than other countries. Among these, we can find Argentina, Australia, Brazil, Chile, China, New Zealand and U.S.A. The only exception to this trend is India, where most of the population prevalently consumes a vegetarian diet. This country doesn’t show any important change in meat consumption over the last decades(www.ourworldindata.org). The type of meat consumed changes across each country. On average, poultry and pork are the most consumed worldwide (www.fao.org). In 2018 FAO estimated that roughly 69 billion chickens were slaughtered for meat produc- tion. The countries with the highest poultry density are Brazil, China and U.S.A (www.fao.org). With this data overview, it is interesting to understand why poultry meat is largely consumed and why it is convenient to raise chickens for meat. It is well known that chickens underwent an important selection within the past decades. The same genetic stock can grow globally, under any type of husbandry conditions. Through the genetic selection, the chickens’ weight has dramatically increased, yet the FCR has de- creased (Brameld et al.; 2016). 2 Chickens specifically reared for meat are called broilers. These animals underwent a strong selection in order to reach market weight at a very young age as, broilers are slaughtered at 43 days of age, on average (Bianchi et al.; 2007). In 1985, broilers at 35 days of age required 3.22 kg of feed to reach a weight of 1.4 kg and had a FCR of 2.3. In 2010, broilers only required 3.66 kg of feed in order to reach a body weight of 2.44 kg at 35 days, with a FCR equal to 1.5 (Siegel et al.; 2014). In other words, modern broilers are able to produce more meat while consuming less feed. This development obviously comes with health implications since artificial selection led to several health and welfare problems. Broiler diseases may depend on their genetics and physiology. Moreover, also the farming condition can affect diseases development. Among the several diseases that affect broilers we can find: 1) Cardiovascular dysfunctions: broilers are selected to abnormally develop their breasts and thighs. The organs, on the other hand, do not grow proportionally to the targeted muscles. This incongruous ratio between energy-supplying and energy-consuming or- gans leads to various metabolic disorders, such as ascites and “sudden death syndrome” (Baghbanzadeh et al.; 2008). a) Ascites (picture 2) is characterized by myocardial hypertrophy and dilatation, abnor- mal liver function, pulmonary insufficiency, and hypoxemia (Luger et al.; 2003) b) SDS (“sudden death syndrome”) mainly affects fast-growing chickens. Suddenly the broiler, even though it appears to be healthy, flaps its wings, fallsto the side and dies. This all happens under a minute (Newberry et al.; 1987). In Europe this syndrome usually affects 3% of birds (Turner et al.; 2014). 2) Skeletal dysfunctions(picture 3): varus and valgus deformities, osteodystrophy, dyschon- droplasia and femoral head necrosis are common in broilers. These dysfunctions lead to a severe lameness in the chickens, inducing them to spend more time lying on the ground and sleeping. If the broilers spend too much time lying down, under the abnormal weight of their bodies, not only can they suffocate, but also, they will develop integument lesions (Juliani; 1998). 3) Integument lesions: these birds are often subjected to dermatitis (e.g.: hock burn, footpad lesions), hyperkeratosis and necrosis of the epidermis (picture 4). This is not only due to the poor blood circulation, but also due to the prolonged contact with the ammonia in the litter (Greene et al.; 1985). Another issue related to the production of poultry meat is its important environmental im- pact. Feeding poultry requires a huge quantity of feed and these animals annually excrete important amounts of nitrogen and phosphorus to the environment, which conditions the production sustainability of this chain (Andretta et al., 2021). Nevertheless, poultry produc- tion has been found to be relatively environmentally friendly compared to other livestock productions, such as that of cattle. (Leinonen et al., 2016). The environmental impact of poultry production can roughly be divided into feed production and transportation, housing emissions and manure emissions. One of the main critical aspects related to poultry production is the amount of feed necessary to grow these animals. These feeds are particularly high in proteins, in order to satisfy the high requirements of chickens. Poultry feeds are made of cereals and their by-products (e.g.: corn, wheat, corn gluten meal), vegetable protein meals (such as soybean meal), oils, vita- mins and minerals. The most important protein source in poultry feed is soybean, usually given as a meal. This ingredient is high in proteins, low in fibers and high in lysine and tryptophan (even if deficient in methionine). Soybean meal is relatively inexpensive com- pared to other protein sources, such as corn gluten meal. The main issue related to soybean isthat it has a strong impact on the environment, mainly due to the fact that in the past couple of decades some areas around the world (like South America and South Asia) have been converted from natural foreststo soya crops (Kastens et al.; 2017). Then this ingredient must be transported to the feed mills around the world (mainly Europe, America and Asia). The loss of ecosystem carbon storage as a consequence of such conversion was added to the carbon dioxide emissions, therefore to the global warming potential arising from this system (Leinonen et al; 2016). For what concerns the housing emissions, recent studies show an important difference in terms of emissions based on the type of housing system. Three systems were taken into consideration: standard (indoor), free range and organic. Studies show that less intensive poultry systems had higher environmental impacts compared to the more intensive ones (Leinonen et al; 2016) in such way: organic systems have higher contributions in terms of eutrophication potential and acidification potentials (due to the emissions of NH3 and N2O), but extensive poultry production can reduce the use of fossil fuels, fertilizers and has lower housing emissions (Leinonen et al.; 2016). Although organic systems show less manure in the litter, it still has an environmental impact. On average, a single broiler excretes 0,6kg of N and 0,1kg of P each year. The amount of N found in the uric acid, expresses as kg/year, is equal to 0,5 (Rotz; 2004). Usually, poultry manure is used as a fertilizer, although it must be 6 used with caution due to the high concentration of N, P and K. If used incorrectly, it could severely damage the crops and it could lead to the excessive eutrophication and acidification of the soil (Leinonen et al.; 2016). Despite what preceded, how could we possibly reduce the environmental impact of poultry meat production? Scientists all over the world are trying to find new farming strategies in order to produce high quality meat with a lower environmental impact. Genetic selections, as stated before, has improved the FCR of animals (chickens can now produce more while eating less feed, at a faster rate), but the main ingredients in feed cannot be totally substituted now. The main challenge nowadays is to find an appropriate substitute for soybean meal, which is known to be the least environmental-friendly ingredient. The purpose of the project POULTRYNSECT is to test the effects of live insect larvae on slow and medium-growing organic chickens to allow sustainable meat production and to improve animal welfare. Insect larvae are reared on organic food by-products and are used as feed ingredient and environmental enrichment for chickens

Breaking down barriers: live or dehydrated dietary whole black soldier fly larvae supplementation in slow growing chickens preserve meat quality and sensory traits

This study investigated the effects of supplementing the diet of a slow-growing autochthonous chicken breed with dehydrated or live Black Soldier Fly Larvae (BSFL) on meat quality and sensory attributes. The research, conducted at the University of Turin, Italy, involved 144 male birds distributed in three experimental groups. The control group (C) was fed a basal diet in which soybean meal was completely substituted with alternative ingredients. The 2 experimental groups were administered a diet identical to the control group but supplemented with either whole dehydrated black soldier fly larvae (DL) or whole live black soldier fly larvae (LL) at a level equal to 5% expected daily feed intake of dry matter. We evaluated the following parameters: nutrient intake, slaughtering performance, physical and nutritional meat quality, fatty acid composition, proteomics, and sensory characteristics. The results demonstrated BSFL supplementation to have no detrimental effects on overall meat quality or sensory attributes. Specifically, there were no significant differences in physical meat quality parameters, nutritional composition, lipid oxidation, or protein digestibility between control and BSFL-fed groups. Fatty acid analysis revealed higher concentrations of lauric and myristic acids in BSFL-fed chicken breast (p < 0.005), suggesting potential nutritional benefits from the supplement. The proteomic analysis also showed no significant differences in the expression of abundant proteins in the breast meat between groups, indicating minimal physiological impact of BSFL supplementation. Overall, this study provides reassurance to consumers and industries about the suitability of BSFL as a sustainable feed supplement for poultry that also offers potential benefits in terms of optimizing the fatty acid profile of chicken meat.publishedVersio

Sensorial evaluation of breast of chicken reared in organic system and supplemented with live black soldier fly larvae

Live larvae fed to poultry has shown to provide good nutrients and bioactive compounds with positive effects on bird's health. However, trials on chicken reared for meat consumption are still scarce. A total of 240 Label naked neck (LNN) birds were reared from 21 to 82 days of age, and four experimental groups (10 birds/pen, 6 replicates/treatment) were considered according to the birds’ gender and larvae provision. Experimental groups were fed 10% supplementation of black soldier fly (BSF) live larvae based on the daily feed intake. Birds (12/diet, 2 birds/pen) were slaughtered according to the standard EU regulations. Following storage at 4°C for 24 h, breast fillets were excised, vacuum packaged and transported to the laboratory for analysis. Vacuum packed breasts were cooked in a water bath at 75°C for 45 min, then breast color and drip loss were measured. Sensory descriptive analysis was performed, in duplicate, by 11 trained judges, experts in sensory evaluation with a specific software for sensory data acquisition, (FIZZ Biosystèmes), using a nine points intensity scale. Results were elaborated by a statistical analysis using R software. Color measurement, drip loss percentage and sensorial profiles were analyzed through the ANOVA and post hoc test (Tukey’s HSD). No significant differences were found in mean percentages of drip loss while color measurement showed only differences based on chicken gender and only for the b* (yellowness) parameter that resulted higher in females. Concerning sensory evaluation, no significant differences were found. In conclusion, results highlighted that a dietary 10% supplementation of BSF live larvae did not affected sensorial quality of breast fillets of LNN chickens reared in an organic production system. The authors acknowledge the financial support for Poultrynsect project provided by transnational funding bodies under the Joint SUSFOOD2/CORE Organic Call 2019

Cecal volatilome and microbiota profile of organic chickens supplemented with black soldier fly live larvae

Insects have shown to be a potential nutritional replacement in poultry nutrition as substitute of traditional protein sources, with positive effects on gut microbiota. However, only few studies have investigated the effects of live black soldier fly (BSF) live larvae provision on short-chain fatty acids (SCFAs) and microbiota composition in chicken’s gut. Label naked neck (LNN, n. 240) chickens were reared in an organic production system from 21 to 82 days of age and randomly allocated into four experimental groups (10 birds/pen, 6 replicates/treatment) according to bird gender and larvae provision. Experimental groups were fed with 10% supplementation of BSF live larvae, based on the expected daily feed intake (DFI). At slaughter, samples of cecal digesta were collected from 60 animals (15 birds/treatment), frozen and stored at -80°C until to be analyzed by SPME-CG-MS and DNA sequencing techniques, respectively. Results showed that seven SCFAs were identified, with butyrate as the most abundant. Even if no significant differences were found between treatments, the cecal SCFAs concentration in insect-fed animals were noticed to be less variable than control group. Cecal microbiota analyses of birds fed with BSF live larvae, showed a higher incidence of Coprobacillus, Synergistaceae and Christensenellaceae, with the latter to having the potential to degrade chitin’s insect meal, a compound with immunoregulatory properties. In conclusion, results showed that even a dietary 10% supplementation of BSF live larvae can slightly improve microbiota profile and potentially, SCFAs production in LNN chickens. These results confirm what observed in recent studies on broilers, but with lower (5% of DFI) live larvae inclusion levels. Financial support for Poultrynsect project was provided by transnational funding bodies under the Joint SUSFOOD2/CORE Organic Call 2019