摘要：The domestic fowl, as a species, is considered a unique experimental model in immunological research where the humoral and cellular components of the immune response can be delineated by selective surgical bursectomy of newly hatched chicks combined with sublethal whole-body X-irradiation. Search for an effective, safe, and a short-acting general anesthetic for application in such young birds is, therefore, essential. Ketamine is a phencyclidine derivative with analgesic and anesthetic properties in both mammalian and avian species. Studies on its efficacy on young or naturally small birds, however, are apparently lacking. Our previous studies indicated that dose levels as high as 51 mg/kg and 37.2 mg/kg are not lethal to 2-day- and 6-day-old Hisex White domestic fowl chicks when given intramuscularly, respectively. Results of the present study show that the onset of ketamine anesthesia varied between 40 - 98 seconds in 2-day-old chicks of this breed depending upon dose level. The dose and response are inversely related (y = -19.3x + 107.5) where “y” is the time for onset of anesthesia in seconds and “x” is the dose as mg/bird. The time for recovery from anesthesia also varied (6.6 - 74.7 min) depending upon dose level. The dose and response, however, are positively correlated (y = 20.92x - 21.15). Doses ranging between 43.77 to 47.74 mg/kg are considered optimum to produce anesthesia with onset in 74 - 77 sec and recovery within 12 - 15 min. It is concluded that Ketamine has the potential for application as a general anesthetic for domestic fowl chicks for bursectomy. Critical clinical tests are necessary to evaluate further the performance of this drug when administered to young chicks.
