Antiserum against arginine vasotocin (AVT) was produced by immunizing a goat and two rabbits with a conjugate of human immunoglobulin (IgG) and AVT. An antiserum, with a maximum binding of 91% at a final dilution of 1:100 was obtained from rabbit No. 2 after the 19th intradermal injections of the conjugate.This antiserum (R2-Kyushu) did not show significant cross-reaction with oxytocin (OT) or mesotocin (MT), (i. e. less than 0.001% cross-reactivity), but showed 51.3% crossreactivity to arginine vasopressin (AVP).Since the neurohypophysis of amphibians, reptiles and birds contains only AVT and MT but not AVP, R 2-Kyushu antiserum can be used to measure the AVT of samples from these animals by radioimmunoassay.

It is known that the time requiredfor capacitation is of a short duration in the fowl. Regularly laying W. L. hens were used. They were maintained in individual cages and received a daily light regimen of 14 hours. Time of oviposition was recorded from 8 A. M. to 4 P. M. for at least 4 weeks prior to the experiment.All instruments, absorbent cotton, etc. used in this study were sterilized. Semen was collected from 3 to 5 roosters by one-man technique6) and pooled. Before semen collection, the entire part of the cloaca was cleaned with 70% alcohol. Care was also taken to avoid the contamination of the semen with feces during the collection. The pooled semen was diluted with an equal volume sterile phosphate buffer containing 2mg dihydrostreptomycin and 0.4mg oxytetracycline per ml, and placed in a refrigerator until its use (stock diluted semen).Jap. J. Zoctech. Sci., 44, (11): 564-568. 564 1973. 11.

A technique for transbucal hypophysectomy of the fowl using a stereotaxic instrument is described. A total of 95 hens were hypophysectomized by our technique with an operating time of about 10 minutes per bird. About 8% of the birds died soon after the operation either as a result of injury to the brain or from hemorrhage or an overdose of Nembutal and 13% were found to be incompletely hypophysectomized. The results suggest that our new techinique for hypophysectomy of the fowl is usetul not only for inexperienced operators but also for technicians trained for orthodox hypophysectomy, since location of the pituitary is quite accessible and the instrument provides considerable accuracy in the subsequent drilling.

The insertion of an artificial yolk (A. Y.) into the oviduct and the prevention of oviposition by a surgical means or by injection of progesterone were performed to investigate the initiation of secreting egg shell material in the uterus .

The domestic hen maintains fertility for long periods after a single mating or artificial insemination (A. I.). Physiological conditions in the reproductive tract of the hen must be such as to maintain the spermatozoa in a functional state. MIMURA (1939)12) and VAN DRIMMELEN (1946)23) observed that the spermatozoa become rapidly distributed throughout the oviduct after A. I. and they disappear long before production of fertile eggs ceases. ALLEN and GRIGG (1957)1) estimated from the radioactivity of 32P-labelled spermatozoa that a small but significant number of spermatozoa reached the infundibulum 1 hour after intravaginal A. I. VAN DRIMMELEN (1946) Later VAN KREY, OGASAWARA and LORENZ (1966)24) and LORENZ and OGASAWARA (1968)11) reported that intramagnal or intrauterine A. I. leads to a higher incidence of early mortality, severe retardation and other abnormalities of the embryo. Materials and MethodsWhite Leghorn roosters, young pullets and yearling hens in active egg production were used. Semen was collected as clear as possible from eight to ten roosters by the one-man technique (BOGDONOFF and SHAFFNER, 19546)), unless otherwise stated. The pooled semen was in a jar. The amount of semen deposited in the oviduct was 0. 1ml and in most cases hens that had soft-shelled eggs in the uterus were used for the surgical and normal A. I. Eggs laid following A. I. or treatments were incubated for 4 or 5 days and examined for embryonic development. Incubation of spermatozoa in various regions of oviductFor the operation the feathers were plucked from the abdomen and tincture of iodine was applied entirely on the abdominal area. Care was taken to have all instruments, glasswares, Jap. J. Zootech. Sci., 42, (5): 237-249. 237 1971. 5.