Impact of Dietary Zinc Oxide Nanoparticles on Productive and Reproductive Performance of New Zealand White Rabbits

Abstract

A comparison study was done to investigate the impact of Zinc Oxide Nanoparticles (ZnO-NPs), that was physically prepared and characterized in the lab, to commercial in organic Zinc Oxide on the productive performance, reproductive performance, biometric indices, lipid profile, total antioxidant capacity (TAC), and Zinc (Zn) concentration in some tissues of Adult and growing NZW rabbit. A total of 481 live-born rabbits were utilized throughout this study, which was produced through double natural successive mating; the interval time between them was 20 min. by the intensive breeding system between 36 primiparous does and 12 bucks NZW Rabbit (3 does\ buck). The adult 36 primiparous does were 5 months age-old and weight 3.068 ±0.24 kg while 12 bucks were 6 months age-old and 3.326 ±0.85 kg weigh. Each adult rabbit was individually housed in cleaned and sterilized flat-deck metal cages measuring 60×50×40 cm had a wire screened floor that allowed faeces and urine to fall through. Each doe cage is supplied with nest cage at day 25 of parturition, which measure 45 ×30×35cm with the floor has drain holes spaced 0.5 cm apart made in the bottom of nest box which well-bedded by wheat straw to a depth of 2 cm so maintained the temperature at 30°C inside nest cage. Adult rabbits left for two weeks on the experimental diets for acclimatization before first mating, the experimental trial lasted for 135 days. Growing kids kept in controlled closed nesting cage for the first 13th day of age-old then freely open the door to allow nipping of feed with their does to develop cecum growth, then the nesting cages were removed after 23rd day and allowing kids to roam in their doe’s cages, kids were weaned at 28th age-old and were removed to growing cages which measuring 60×50×40 cm had a wire screened floor that allowed faeces and urine to fall through, not more than 3 kg live rabbit weight in each cage. The sealing weight of growing rabbits was 62 days age-old. The Adult rabbit of all the experimental groups have been housed in the same compartment of the building, where is the temperature of the building and air controlled with the use of coolers and forced ventilation systems to be maintained between a maximum of 23.2°C and a minimum of 16.6 °C throughout the experiment. Relative humidity was adjusted according to the thermal index to be comfortable. The rabbits were given a photoperiod of 16 hours of light and 8 hours of darkness. Each rabbit cage was provided with a water canal and experimental feeder. All rabbits were kept under standard hygienic conditions and were vaccinated against rabbit hemorrhagic disease, bacterial diseases according to the routine prophylactic vaccination program. The experimental groups were as the following: the first group (G1) served as the control positive group supplemented with premix contain Zinc Oxide at 50 ppm (inorganic Zinc source), the second (G2) supplemented with premix contain zero ZnO as control negative group, the third group (G3) were supplemented with premix contain prepared ZnO-NPs at half dose 25 ppm while the, fourth group (G4) were supplemented with premix contain prepared ZnO-NPs at full dose 50 ppm. The productive performance parameters in the four experimental groups including Final body weight, weight gain, and birth weight, weaning weight and sealing weight at 62 days age old, feed consumption, and mortality rates were recorded and feed conversion ratios were calculated.