M. Konishi et al., EFFECT OF ACTIVE IMMUNIZATION OF CATTLE AGAINST INHIBIN ON OVARIAN FOLLICULAR DEVELOPMENT AND ULTRASOUND-GUIDED TRANSVAGINAL FOLLICULAR ASPIRATION, Theriogenology, 46(1), 1996, pp. 33-43
The effects of active immunization of cattle against inhibin on ovaria
n follicular development and ultrasound-guided transvaginal follicular
aspiration were determined. Six Multiparous Japanese Black were activ
ely immunized with a synthetic peptide replica of the amino acid seque
nce from 1 to 26 (numbering from the N-terminal end) position of the a
lpha-subunit of porcine inhibin (pINH) conjugated with rabbit serum al
bumin (RSA) using Freund's complete adjuvant. At 6, 10 and 14 wk after
the primary injection, booster injections of the peptide were given.
As controls, 6 Japanese Black received rabbit serum albumin as describ
ed above. Blood samples were taken at 0, 2, 6 wk and once a week from
10 to 17 wk after the primary injection to measure antibody titer. The
changes in the numbers of recruited follicles of the 3 size categorie
s (small, 2 to 3 mm; medium, 4 to 9 mm and large, greater than or equa
l to 10 mm) and aspirated oocytes were examined once a week from 10 to
17 wk using ultrasound scanning. Antibody titers increased after the
first booster in all immunized cattle. In comparison with controls, in
hibin-immunized cattle had more small, medium and large follicles duri
ng the ultrasound scanning (16.0+/-1.8, 4.0+/-0.6 and 2.2+/-0.3 versus
9.1+/-0.5, 1.7+/-0.2 and 1.1+/-0.1, respectively; P < 0.05). In addit
ion, the number of oocytes collected by transvaginal follicular aspira
tion was significantly greater (P < 0.05) in the inhibin-immunized cat
tle (10.4+/-1.7) than in the controls (4.2+/-0.5). These results demon
strate that in cattle active immunization against inhibin can enhance
ovarian follicular development and the number of oocytes collected by
transvaginal follicular aspiration.