INFLUENCE OF FEED RESTRICTION AND ZINC OXIDE NANOPARTICLES SUPPLEMENTATION ON GROWTH PERFORMANCE, BLOOD BIOCHEMISTRY, INTESTINAL MORPHOLOGY AND CECAL FERMENTATION PARAMETERS OF GROWING RABBITS

Abstract

The present study investigated the response of growing rabbits in terms of growth performance, serum biochemical, intestinal morphology, and caecal fermentation parameters to feed restriction and zinc oxide nanoparticles (ZnO-NPs) supplementation. A total of 60 New Zealand male rabbits were randomly distributed into 6 groups: AL-0 (fed ad libitum + fresh water as control); AL-15 and AL-30 (ad libitum + water supplemented with ZnO-NPs in water, 15 and 30 mg/L, respectively); and R-0, R-15 and R-30 were the same as the first 3 groups but with restricted feeding regime. Rabbits fed ad libitum and supplemented with ZnO-NPs (15 mg/L) showed the highest body weight with no significant difference from AL- fed groups or R-0. Feed conversion ratio (FCR) showed no difference among the different experimental groups (P > 0.05). ZnO-NPs supplementation reduced the serum lipid profile parameters, catalase enzyme in R-30, superoxide dismutase in AL-15 and AL-30 while increased serum malondialdehyde (MDA) in both ad libitum and restricted rabbits. ZnO-NPs administration resulted in lower caecal ammonia in AL-30 compared to its control (AL-0) as well as the content of individual volatile fatty acids (VFAs) (acetate, butyrate and propionate) (P 0,05). Dodajanje ZnO-NP je vplivalo na zmanjšanje parametrov lipidnega profila v serumu, tj. encim katalaza pri R-30 in superoksid dismutaza pri AL-15 in AL-30, medtem ko se je vsebnost serumskega malondialdehida (MDA) povečala tako pri kuncih, krmljenih ad libitum, in kuncih z omejenim režimom krmljenja. Dajanje ZnO-NP je pri AL-30 v primerjavi s kontrolo (AL-0) povzročilo znižanje vsebnosti amonijaka v slepem črevesu ter vsebnosti posameznih hlapnih maščobnih kislin (acetata, butirata in propionata) (P < 0,05). Kot odgovor na omejitev krme in dodajanje ZnO-NP so se spremenili morfološki parametri ileuma (dolžina sluznice, dolžina resic in število čašastih celic). Ključne besede: omejitev krme; rast; kunci; nanodelci Zn oksida

Keywords

• feed restriction
• growth
• rabbits
• Zn oxide nanoparticles