The effect of phytase and inorganic Zn supplementation was studied in 180 male White Pekin ducks (WPD) from 1 to 56 days of age. The birds were divided into four groups fed the same basal diet (containing 26 ppm of Zn from raw materials): the control group did not receive Zn supplementation; the second group was supplemented with 30 ppm of Zn oxide; and the third and fourth groups were fed the control and the 30 ppm diets, respectively, both supplemented with 500 U of E. coli phytase. Each group contained five replicates of nine ducks. The body weight and feed intake were recorded at 1, 28 and 56 days of age. At 56 days of age, five birds/group were used to measure feed digestibility and five other birds/group were slaughtered. Zn at 30 ppm increased the body weight gain (BWG, p < 0.01) and feed intake (p < 0.05) and improved the feed conversion (FCR, p < 0.05) of the growing ducks. The Zn retention and Zn level in the excreta increased (p < 0.01) due to Zn supplementation. The addition of phytase improved BWG (p < 0.01) and FCR (p < 0.05) of growing ducks. The use of phytase reduced (p < 0.01) the level of Zn in duck excreta. Phytase supplementation to the basal diet at 30 ppm seems to be adequate to meet Zn requirements for ducks without further Zn additions.

To evaluate the effects of feeding a Hermetia illucens (HI) larvae meal on the different intestinal traits of hens, and to determine the toxic elements’ concentration in the insect meal and diets, 162 hens were randomly allotted to three groups. The control received a corn-soybean meal-based diet (SBM); the HI25 and HI50 groups received two diets in which the 25% and 50% of the dietary protein were replaced by the HI protein, respectively. The duodenal and jejunal villi height and villi/crypt were higher (p < 0.01) in the SBM than in the HI groups. The ileal villi height was higher (p < 0.05) in the SBM and HI25 groups than the HI50. The HI50 group exhibited a lower duodenal maltase activity. The intestinal alkaline phosphatase (IAP) activity linearly decreased in the duodenum and jejunum as the dietary insect meal inclusion increased. The HI50 group had a higher acetate and butyrate level than the SBM. The levels of cadmium (Cd), lead (Pb), mercury (Hg), and arsenic (As) in the diets and insect meal were lower than the maximum values established by the EU Commission. The 25% soybean protein replacement with Hermetia illucens larvae meal in the diet of laying hens was more suitable and closer to the optimal level than 50%.

Simple SummaryThe rabbit farming sector is going through a difficult period. The reduction in the consumption of rabbit meat and the increased attention paid by consumers to the welfare of farmed animals require the adoption of farming methods that are as “natural” as possible and at the same time may ensure the maintenance of good growth performance. In this sense, free-range breeding on the ground and in colonies allows the rabbits to express more natural behaviour, but it also presents some negative aspects such as decreased growth performance, higher energy expenditure of subjects due to a higher locomotion activity, and the need for a larger rearing space. Mirrors can represent a valid solution by improving the rabbits welfare and at the same time ensuring good growth performance and carcass quality traits.AbstractThe aim of this work was to propose a model of free-range raising for rabbit able to maximize the animal welfare and at the same time the productive performances through the use of mirrors. A total of 81 rabbits were allocated into free-range areas and divided into three groups (nine replicates per group): in the first group (face to face, F2F), the rabbits of each replicate could see each other. In the second group (blind) each replicate was isolated from the others; in the third group (mirrors), the replicates were divided as for the Blind group but two mirrors were placed in a corner of the perimeter. The blind group rabbits showed the lowest final weight (p < 0.05), while rabbits from the mirrors groups showed the best FCR and net dressing out values. The blind group showed the highest production of total short chain fatty acids, acetate (p < 0.05) and propionate (p < 0.01). The F2F rabbits showed higher levels of creatine phosphokinase and lactate dehydrogenase and lower values of blood glucose than those of the other groups, due to the higher locomotion activity. The use of mirrors can improve rabbit’s growth performance and carcass traits by lowering the rabbit’s locomotion activity in comparison to the other tested systems.

Population growth and rapid urbanisation have increased the global demand for animal feed and protein sources. Therefore, traditional animal feed production should be increased through the use of alternative nutrient sources. Insects as feed are beginning to fill this need. One such insect is the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae). However, to more effectively mass produce the black soldier fly, a better understanding of its thermal biology is needed. Thus, the aim of this study was to evaluate the impact of age, size, and sex on adult black soldier fly thermal preference. The thermal preference of adult black soldier flies was determined by exposing flies to a thermal gradient with a range of surface temperatures and monitoring their positions over time. An aluminium plate was used to create a linear thermal gradient where surface temperatures ranged from ~15-60 °C. Flies were distinguished by age (1-d-post-emergence vs 7-d-post-emergence), size (large vs small) and sex (male vs female) to assess whether thermal preference differed by specific life-history traits. Thermal preference for 7-d-post-emergence adults was significantly lower (19.2 °C) than 1-d-post-emergence adults (28.7 °C), respectively. Similarly, small adults selected significantly cooler (21.1 °C) temperatures than large adults (26.9 °C). No significant differences in thermal preferences were found between sex, regardless of age or size. In fact, males and females had similar thermal preference of 23.8 and 24.2 °C, respectively. This study reveals that multiple life-history traits of adult black soldier fly affect their thermal preference, and thus should be taken into consideration by mass rearing facilities to optimize production.

A total of 120, twelve wk old female Japanese quails were divided into 4 groups (6 replicates of 5 birds each). The control group ( CON ) fed a corn-soybean diet; in the other 3 groups, Tenebrio molitor larvae meal ( TML ) replaced 5, 10, and 20% of the soybean protein ( T5, T10 , and T20 ). The laying performance and egg quality were studied for 54 d. The data were processed by a one-way ANOVA; the orthogonal contrast analysis was performed to test the linear, quadratic and cubic effects among the means. The laying rate and egg mass linearly decreased ( P < 0.01) as the TML inclusion level in the diet increased. The egg weight and feed conversion ratio linearly increased from the control to T20 diet ( P < 0.01) while the digestibility of dry matter, organic matter, and crude protein linearly decreased ( P < 0.05). The albumen and yolk weight showed a linear increase ( P < 0.01) due to dietary TML inclusion, while the eggshell weight showed the opposite ( P < 0.05). The estimated activity of Δ9-desaturase (C16:0), Δ5+Δ6-desaturase on both polyunsaturated fatty acid n-6 and n-3 linearly increased ( P < 0.05) as affected by dietary TML. The boiled yolk lightness ( L* ) showed higher values in T5 and T10 groups (quadratic contrast, P < 0.01). The yolk redness index ( a* ) showed lower values in T5 and T20 than control and T10 groups (cubic contrast, P < 0.01). The albumen L*, a* , and b* indexes showed a significant effect of the quadratic contrast ( P < 0.05). In addition, the albumen b* index showed a significant effect of the cubic contrast ( P < 0.01). The total lipids showed the highest values (cubic contrast, P < 0.05) in the T10 and T20 groups. The total monounsaturated fatty acids linearly increased ( P < 0.05) according to the increase of dietary TML. The best inclusion level of defatted TML meal for laying quails seems to be 1.4% of diet, corresponding to the T5 diet.

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Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value. During its larval stage the black soldier fly Hermetia illucens is extremely voracious and can feed on a wide variety of organic materials. To study the impact of different fruit byproducts on the insect's growth, final larval biomass, substrate reduction, bioconversion parameters, and larval nutritional composition, 10 000 black soldier fly larvae (BSFL) were reared on 7.0 kg of one of three substrates (strawberry, tangerine, or orange) or on a standard diet as a control. The results highlight that BSFL can successfully feed and grow on each of these diets, though their development time, growth rate, and final biomass were differently impacted by the substrates, with strawberry being the most suitable. The lipid and protein contents of BSFL were similar among larvae fed on different substrates; however, major differences were detected in ash, micronutrient, fiber, fatty acid, and amino acid contents. Overall, the results indicate that fruit waste management through the BSFL bioconversion process represents a commercially promising resource for regional and national agrifood companies. Our study offers new perspectives for sustainable and environmentally friendly industrial development by which fruit byproducts or waste might be disposed of or unconventionally enhanced to create secondary products of high biological and economic value, including BSFL biomass as animal feed or, in perspective, as alternative protein source for human nutrition.

Thermal stresses from both environmental conditions and organismal crowding are common in mass production of the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae). In this study, upper and lower critical thermal (CT) limits (i.e. knockdown CTmax and CTmin) for the adult black soldier fly were determined. Impacts of size, age, and sex on these critical temperatures were also assessed. The CTmax ranged from 45.0-51.0 °C with larger and older adults having a ~1 °C higher CTmax than smaller and younger adults. However, no differences in the CTmax were found between sexes, regardless of age or size. The CTmin ranged from 8.0 to 13.0 °C with larger and older females having a ~1 °C higher CTmin than males and smaller or younger females. While reporting the upper and lower critical temperatures, this study also revealed the thermal breadth (i.e. the range of body temperatures over which organisms can locomote) for adult black soldier flies across age, sex, and size. Based on these data, and when recognising not all fly populations are the same, mass-rearing facilities should determine the CTmax and CTmin for their fly population in order to optimise mating and fertile egg production, and ultimately maximise profits and sales. One degree of temperature can be the difference between success and failure in industrialised facilities.