Diet supplemented with olive cake as a model of circular economy: Metabolic and endocrine responses of beef cattle

Abstract

IntroductionIntegrating by-products into livestock diet represents a great opportunity for implementing the concept of circular economy while reducing feed costs. Olive cake (OC) is considered an agro-industrial waste, but the high content of valuable metabolites makes it a promising feed integration. Therefore, this study investigated the effect of OC integration in beef cattle diet on different blood parameters.MethodsForty-eight young growing fattening Limousines-−24 bulls (body weight 350 ± 15 kg) and 24 heifers (280 ± 10 kg)—, aged 240 ± 20 days, were randomly allocated to 1 of 3 dietary treatments: concentrate at 0% (Control group: CTR), 10% (Low-olive cake group: L-OC), or 15% (High-olive cake group: H-OC) of OC inclusion. Blood samples and body weights were collected before administrating the supplemented diet (0 d), at the end of the stocker growing phase (56 d), and at the end of the fattening (147 d). After being slaughtered, animal carcasses were weighted. A linear regression model was fitted for each blood parameter with the 0 d as covariate and diet, time, sex, diet × time, and diet × sex as fixed effects.ResultsIn males, body weight was highest in CTR, but carcass weight was similar in all the groups. All the blood parameters were within physiological ranges, independently from the animal diet. CTR group showed the highest alanine aminotransferase (ALT, P = 0.0027) and creatine kinase (P = 0.0119), whereas total bilirubin (P = 0.0023) was higher in H-OC than in CTR. Moreover, ALT was highest in CTR at 56 d, becoming similar in all the groups at 147 d (P = 0.0280). Instead, the increase observed in total cholesterol from 56 to 147 d was lower in H-OC compared with CTR and L-OC (P = 0.0451). A significant effect of diet × sex interaction was observed on triglycerides, urea, liver enzymes, and insulin. These data support the OC inclusion of up to 15% of the concentrate with no detrimental effect on beef cattle metabolic status.DiscussionIn conclusion, OC can be considered as a component in beef diet giving an opportunity to improve agriculture sustainability.

Growth Performance, Blood Metabolites and Carcass Characteristics of Black Goat Kids Fed Diets Containing Olive Cake

“…Consequently, the utilization of OC as an alternative feed for black goats is economically advantageous. This finding aligns with the prior scientific literature that has explored the use of alternative feeds as a means to decrease the expenses associated with traditional animal diets [19][20][21].…”

“…Concerning serum metabolite profiles, we observed that only ALT levels were lower in the blood of kids who received OC75 and OC150 diets. The decline in the activity of this enzyme can be attributed to the influence of antioxidants and polyphenols on the liver [20]. The concentrations of all other blood serum metabolites related to lipids (cholesterol, LDL, HDL, triglycerides), renal function (urea, creatinine), and liver function (glucose, AST, ALP) were unaffected by the inclusion of OC when compared to the CON group.…”

Effects of Dietary Enrichment with Olive Cake on the Thyroid and Adrenocortical Responses in Growing Beef Calves

“…The experimental design of this study was previously described by Bionda et al [ 29 ]. Briefly, a total of 48 young Limousine calves (24 non-castrated bulls and 24 heifers), aged 250 ± 20 days at the time of first sampling, were randomly assigned to one of three dietary treatment groups and segregated according to sex and body weight (BW).…”

“…To the best of our knowledge, no previous studies have been carried out to evaluate the impact of olive cake integration in calves’ diets on their thyroid and adrenocortical response. Thus, in view of the above, and given that, especially in the Mediterranean area, the incorporation of olive cake in beef diets is now being encouraged as a good strategy for sustainable animal husbandry and circular economy [ 2 , 29 ], this study aimed to investigate whether dietary enrichment with olive cake can induce an effect on the homeostasis status of thyroid and adrenocortical activities in growing beef animals.…”

Influence of olive cake dietary supplementation on fecal microbiota of dairy cows

“…Recently, the use of agro-industrial by-products as feed supplements in animal nutrition represents an interesting and successfully adopted strategy to reduce feeding costs and satisfy the nutritional needs of livestock ( Chiofalo B. et al, 2020 ; Chiofalo V. et al, 2020 ; El Otmani et al, 2021 ; Bionda et al, 2022 ). In this context, the use of by-products of the olive oil industry, such as destoned olive cake, became widespread as a feed supplement since they are rich in nutraceutical molecules with antioxidant and antimicrobial features, including polyphenols (flavonoids, anthocyans, cyanidins, and phenolic acids), tyrosol, hydroxytyrosol, and oleuropein ( Mannelli et al, 2018 ; Foti et al, 2022 ).…”