Improvement in the in vitro Digestibility of Shrimp Meal by the Addition of Persimmon Peel

Dehydrated and live black soldier fly larvae as environmental enrichment in indigenous slow-growing chickens: performance, gut health, and chitinolytic enzyme activity

The demand for sustainable and ethically farmed animal products is on the rise as consumers become more environmentally and animal welfare conscious. The need to diminish the consumption of soybean meal is urgent, and companies are looking for ways to respond to this necessity by looking for alternatives to soybean meal. This study assessed the impact of introducing whole dehydrated and live black soldier fly larvae (BSFL) into the diet of an indigenous chicken breed as environmental enrichment. A total of 144 39-day-old male Bianca di Saluzzo chickens were distributed among 18 pens and assigned to three different experimental groups. The control group received a diet where soybean meal was entirely replaced by alternative ingredients. The two experimental groups were given the same diet supplemented with 5% of the expected daily feed intake of whole dehydrated BSFL or whole live BSFL. Throughout the trial period (from the bird age of 39-174 days of age), live weight was recorded every 21 days, and the average daily gain, daily feed intake, and feed conversion ratio were calculated. The time required for the birds to consume the larvae was recorded three times a week. At age 147 and 174 days, 12 birds per treatment were selected based on mean live weight and slaughtered. Measurements included hot and chilled carcass weights, organ weights (spleen, liver, heart, stomach), breast and thigh muscle weights, and the corresponding yields were calculated. Acid protease activity was measured in proventriculus extract, and chitinase and chitosanase activity was calculated based on the release of reducing sugars from chitin or chitosan. The results showed little improvement in final live weights and daily feed intakes of the animals fed the insect larvae compared with control birds. Larva supplementation had no negative impact on the overall well-being of the animals assessed by blood analysis and histopathological assessment of the intestinal tract, spleen, and liver. No differences were found between the dehydrated vs live insect larvae consumption times, with all larvae being eaten up very rapidly (< 3 min). The birds fed BSFL showed an increase in chitinase activity. These findings support the potential use of whole BSFL as a form of environmental enrichment, particularly in their dehydrated form, being more convenient to use and store, which would also encourage the uptake of this practice by farmers.

Effects of Persimmon Peel on Laying Performance, Nitrogen Availability, and Egg Quality in Laying Hens Provided with Shrimp Meal Diets

To determine whether persimmon peel (PP) showing high chitinase activity could alleviate the detrimental dietary effects of chitin-rich shrimp meal (SM), we assessed the laying performance, nitrogen (N) balance, and egg quality of laying hens provided with SM diets containing PP. We also examined the color and antioxidant properties of egg yolk, as we anticipated these would be improved by providing SM and PP. Seventy-two laying hens (45 weeks of age) were allotted to one of the nine dietary treatments (eight hens each), namely three levels of SM (0%, 10%, and 15%)×three levels of PP (0%, 6%, and 8%), and fed with the experimental diets over a period of 6 weeks. Hen-day egg production, feed intake, egg mass, feed conversion ratio, and N balance reduced with increasing levels of SM, whereas the reductions were recovered in a dose-dependent manner in response to increasing levels of PP; however, the SM0% treatment showed that PP exerted little effects. Notably, reductions in the Haugh unit and albumen height of eggs with increasing SM levels, and recovery by provision of increasing levels of dietary PP, were observed. Yolk color was improved by SM, although PP exerted little effect, whereas the antioxidant properties of yolk were enhanced by the inclusion of both SM and PP in diets. Furthermore, eggshell strength, weight, and thickness were enhanced with increasing levels of SM, whereas dietary PP had little effect on these parameters. Thus, we suggest that PP can alleviate the negative effects of dietary SM and improve egg quality, without causing a reduction in laying performance, provided that the level of supplementary PP in diets is less than 8%. These findings accordingly indicate that PP is a promising feed constituent for laying hens fed with SM diets.