Yellow mealworm larvae (Tenebrio molitor, L.) as a possible alternative to soybean meal in broiler diets.

The aim of the study was to evaluate the feasibility of replacing soybean meal (SBM) with Tenebrio molitor larvae (TML) meal in broiler diets. A total of 80 30-d-old male Shaver brown broilers were divided into two groups fed on two isoproteic and isoenergetic diets differing for protein source (SBM vs. TML). Up to 62 d of age, body weight and feed intake were recorded weekly and body weight gain, feed conversion ratio (FCR), protein efficiency ratio (PER) and European efficiency factor (EEF) were calculated. At 62 d, blood samples were collected from 16 birds/group for evaluation of blood profiles. Feed intake was not different between groups considering the entire period of the trial. The FCR was more favourable in the TML than SBM group from 46 d of age and in the entire period of the trial (4.13 vs. 3.62). The PER was higher in the SBM than in the TML group (1.92 vs. 1.37) while the EEF was higher in broilers fed on the TML diet (132.6 vs. 156.2). Albumin-to-globulin ratio was higher in broilers fed on SBM than in the other group (0.44 vs. 0.30). aspartate aminotransferase and alanine aminotransferase were higher in TML than SBM (195.1 vs. 178.6 U/l and 82.07 vs. 46.71 U/l, respectively). Uric acid was higher in broilers fed on SBM than TML (5.40 vs. 4.16 mg/dl). TML did not affect feed intake and growth rate of broilers from 30 to 62 d of age when compared to an isoproteic and isoenergetic SBM diet, but FCR of the TML group was more favourable than that of the SBM group. The lowest albumin-to-globulin ratio in broilers fed on TML suggests a higher immune response, probably due to the prebiotic effects of chitin.

Effect of dietary mannan-oligosaccharides on in vivo performance, nutrient digestibility and caecal content characteristics of growing rabbits.

To evaluate the effect of mannan-oligosaccharides (MOS) on in vivo performance, nutrient digestibility, fermentation characteristics and caecal microbial populations of rabbits, 144 thirty-five days old hybrid Hyla were equally divided into three groups, one of which was fed the same diet without additives (control group), one with antibiotics (colistin sulphate, 144 mg/kg; tylosin, 100 mg/kg; oxytetracyclin, 1000 mg/kg) and one with MOS (1 g/kg of diet). Mortality rate, live weight, feed intake and feed conversion ratio were recorded up to 62 days of age. At 60 days nutrient digestibility was measured by acid insoluble ash method. The caecal content of 10 rabbits per group was collected at 62 days and analysed for volatile fatty acids production, ammonia content and microbial count. Rabbits from the control group had a significantly (p < 0.01) lower body weight at 62 days (1638.9 g vs. 1779.4 g and 1862.5 g, respectively for the control, MOS and antibiotic groups) while the antibiotic group showed a higher (p < 0.05) feed intake than the control group (127.9 g/day vs. 109.3 g/day). Rabbits from the MOS group had a higher apparent digestibility of cellulose (34.27% vs. 29.61% and 27.49%, respectively for the MOS, control and antibiotic groups) and, as a consequence a higher level of acetate in the caecal content (39.93 mmol/l vs. 34.21 mmol/l and 23.09 mmol/l, respectively for the MOS, control and antibiotic groups). Caecal microflora of the MOS group rabbits also had a higher fermentative activity in respect of protein source, as demonstrated by the higher productions of branched chain fatty acids. MOS and antibiotics significantly reduced the colonies of Coliformis (2.32 vs. 3.20 vs. 2.40 logCFU/g, respectively for the MOS, control and antibiotic groups, p < 0.01). Mannan-oligosaccharides at 1 g/kg of diet can be used as an alternative to antibiotics during the rabbit's growth period.

In vitro fermentation characteristics of different carbohydrate sources in two dog breeds (German shepherd and Neapolitan mastiff).

Few studies have been published on the normal intestinal biota of canines unlike the wealth of information regarding livestock animal species. The in vitro gas production technique (IVGPT) including measurements of accumulating gas during fermentation and end-product determinations allows obtaining a complete picture of microbial activity kinetics. The aim of this study was to study the in vitro fermentation characteristics of different carbohydrate sources using inocula from two dog breeds (German Shepherd and Neapolitan mastiff). Faeces sampled from rectum of two GS and NM adult dogs, fed the same dry food, were used as inocula. The samples, diluted and filtered, were incubated at 39 degrees C under anaerobic condition with nine substrates different for carbohydrate composition (rice, corn, potato, spelt, pure cellulose, beet pulp, wheat bran, inulin and fructo-oligosaccharide). Gas production was recorded 17 times using a manual pressure transducer. After 48 h, the fermentation was stopped and fermenting liquor was analysed for pH and volatile fatty acids (VFA). Organic matter digestibility (OMD) was calculated as difference after burning the residuals. OMD, gas production and end-products were significantly correlated with chemical composition of substrates, in particular carbohydrate fractions (total dietary fibre and starch), confirming the effectiveness of the IVGPT in evaluating dog feeds. Concerning the comparison between breeds significant differences (p < 0.01) were found for OMD, gas production, fermentation kinetic parameters and end-products, suggesting a different pathway of fermentation and consequently, a different anaerobic population.

Productive performance and blood profiles of laying hens fed Hermetia illucens larvae meal as total replacement of soybean meal from 24 to 45 weeks of age.

The aim of the research was to study the effects of an insect meal from Hermetia illucens larvae (HILM) as complete replacement of soybean meal (SBM) on productive performance and blood profiles of laying hens, from 24 to 45 wk of age. A total of 108 24-week-old Lohmann Brown Classic laying hens was equally divided into 2 groups (54 hens/group, 9 replicates of 6 hens/group). From 24 to 45 wk of age, the groups were fed 2 different isoproteic and isoenergetic diets: the control group (SBM) was fed a corn-soybean meal based diet, while in the HILM group the soybean meal was completely replaced by Hermetia illucens larvae meal. Feed intake, number of eggs produced, and egg weight were recorded weekly along the trial. At 45 wk of age, blood samples were collected from 2 hens per replicate. The use of HIML led to a more favorable (P < 0.01) feed conversion ratio in hens but lay percentage, feed intake, average egg weight, and egg mass were higher (P < 0.01) in hens fed the SBM diet. Hens fed insect meal produced a higher percentage of eggs from small (S), medium (M), and extra-large (XL) classes (P < 0.01) than SBM, while the SBM group had a higher percentage of eggs from the large (L) class (P < 0.01). The levels of globulin and albumin to globulin ratio were, respectively, higher and lower (P < 0.05) in HILM than the SBM group. Cholesterol and triglycerides were higher (P < 0.05 and P < 0.01, respectively) in hens from SBM than in the HILM group. Blood levels of Ca were higher (P < 0.01) in hens fed insect meal, while creatinine was higher (P < 0.01) in blood of hens fed SBM. Hermetia illucens larvae meal can be a suitable alternative protein source for laying hens even if the complete replacement of soybean meal needs further investigation to avoid the negative effects on feed intake.

Use of larvae meal as protein source in broiler diet: Effect on growth performance, nutrient digestibility, and carcass and meat traits.

The aim of this research was to study the effect of insect meal from larvae ( larvae meal [TML]) as complete replacement of soybean meal (SBM) on growth performance, nutrient digestibility, and carcass and meat traits of broilers. A total of eighty 30-d-old male Shaver brown broilers were homogenously divided into 2 groups (each consisting of 8 replicates of 5 birds). Up to 62 d of age, the groups were fed 2 isoproteic and isoenergetic diets differing for the ingredient used as the main protein source: the control group was fed a corn-SBM-based diet, whereas in the TML group, the SBM was completely replaced by TML. Broiler growth performance was measured during the trial. At 62 d of age, 2 broilers per replicate (16 per group) were slaughtered and apparent ileal digestibility coefficients and carcass and meat traits were determined. The use of TML as the main protein source in the broiler diet had no significant effect on most growth performance and carcass traits and chemical and physical properties of meat, the latter being important for marketing purposes. The feed conversion ratio in the entire experimental period (from 30 to 62 d) was improved in the TML group compared with the SBM group ( < 0.05). The apparent ileal digestibility coefficients of DM, OM, and CP in broilers fed the SBM diet were greater ( < 0.01) than the other group. The full digestive system in broilers fed SBM had a lower ( < 0.05) absolute and relative weight than that of broilers fed TML. Also, the weight and the percentage of the spleen in the SBM group were lower ( < 0.05) than those in the TML group. The length of the entire intestine in the group fed TML was greater ( < 0.05) than the other group and the same happened when intestinal length was expressed as percentage of broiler BW ( < 0.05). Among the different intestinal tracts, the ileum and ceca of broilers fed TML had a greater ( < 0.05) length than that of broilers fed SBM. Also, ceca weight (as an absolute value or percentage on live weight) in broilers fed TML was greater ( < 0.05) than that of broilers fed SBM. Breast pH and cooking losses in broilers fed TML were greater ( < 0.05) than those of broilers fed SBM. Chemical characteristic of meat obtained from right breast of slaughtered broilers were unaffected by dietary treatments. larvae meal can be a suitable alternative protein source for growing broilers and also when used as principal protein contributor to the diet.

Effect of mannanoligosaccharides supplementation on caecal microbial activity of rabbits.

A total of 200 weaned (35 days) hybrid Hyla rabbits were randomly divided among five groups housed in bicellular cages (20 cages per group). Between 35 and 60 days of age, the groups were submitted to the following treatments: group ANT (positive control) fed a basal diet supplemented with antibiotics (colistin sulphate, 144 mg/kg; tylosin, 100 mg/kg; and oxytetracyclin, 1000 mg/kg); groups MOS_0.5, MOS_1.0 and MOS_1.5 fed the basal diet supplemented with 0.5, 1.0 and 1.5 g/kg mannanoligosaccharides (MOS), respectively; another group fed the basal diet without antibiotics or mannanoligosaccarides supplementation (negative control). Along the trial, an episode of epizootyc rabbit enteropathy occurs so that in the control group mortality rate was very high (78%) and survivor rabbits showed severe symptoms of disease (diarrhoea). Thus, the control group was discarded from the trial. At 60 days of age, samples of caecal content were collected from 10 rabbits per group and used as inocula for an in vitro gas production trial. At the end of fermentation (120 h of incubation), organic matter digestibility (OMd), cumulative gas production, fermentation kinetics, pH, volatile fatty acid (VFA) and NH3 productions were measured. Inoculum from MOS_1.0 rabbits showed the significant higher values of OMd (64.21%, P < 0.05), gas production (262.32 ml/g, P < 0.05), acetate (96.99 mmol/g OM, P < 0.05) and butyrate (26.21 mmol/g OM, P < 0.05) than the other groups. Slight differences were recorded among the groups ANT, MOS_0.5 and MOS_1.5. In addition, branched chain acids, in proportion to total VFAs, were significantly higher in MOS_1.0 inoculum (0.04, P < 0.05). MOS are able to affect fermentation activity of caecal micro-organism, but their activities seem not proportional to their level in the diet.