Effects of induced hypothyroidism on ovarian response to superovulation of Brahman (Bos indicus) cows /

(P<.05) in PTU than in C by d 28 of treatment and remained

Bibliographic Details
Main Author: Bernal, Alejandro, 1972-
Format: Thesis eBook
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1996.
Subjects:
Online Access:Link to OAKTrust copy
Description
Summary:(P<.05) in PTU than in C by d 28 of treatment and remained
(Superov') over a 3-d period. Estrus was induced by
administration of PGF20C. Artificial insemination was
adrenal function and increased ovarian response to FSH in
after insemination, collection of embryos by non-surgical
and lower (P<.l) percentage of blastocysts collected than
animal received 1.8 kg of a 5.-l corn-soybean meal
average daily gain, greater (P<.05) paired ovarian weights,
body condition score (BCS) to dietary treatments containing
Coastal bermudagrass hay were available free choice and each
concentrate daily. Dietary treatments began on d 10 of the
corpora lutea than C. Concentration of P4 per g of luteal
cows received daily i.m. injections of 25 IU of porcine FSH
cows were hypothyroid (H-PTU) and four were partially
either 0 (C; n=10) or 4 mg/kg BW/d 6-npropyl-2-thiouracil
estrous cycle. Ten d after the second standing estrus, the
greater (P<.06) amount of luteal tissue, greater (P<.06)
have affected fertility. Ovulation and P4 release appeared
hypothyroidism improved weight gain and BCS, did not affect
low thereafter. Based on T4 concentrations on d 49, five
mid-flank laparotomy. Blood samples were collected on a
mixed with the concentrate (PTU- n=10). Water, minerals and
Multiparous nonlactacting Brahman cows (n=20) exhibiting
normal estrous cycles were randomly assigned within BW and
number of large follicles (>4 mm), lower (P<.001) embryo
of luteinized follicles and a greater (P<.05) number of
performed at 12 and 24 h after observed estrus. Seven d
procedures was performed and the ovaries were removed via
ratio of luteal to serum P4 on d 7 was greater (P<.l) in PTU.
recovery rate, lower (P<.l) percentage of fertilized embryos,
Serum concentration of cortisol did not differ (P>.l) between
superovulated Brahman cows. Enhanced ovarian response may
suppressed (P-PTU). Cows in the PTU group had greater (P<.l)
those in C. Further, H-PTU cows had a greater (P<.06) number
tissue did not differ (P>.l) between treatments, but the
to be impaired in hypothyroid Brahman cows.
treatment groups. It was concluded that induced
triiodothyronine and thyroxine (T4) concentrations were lower
weekly basis and the d of embryo collection. Serum
Item Description:"Major subject: Physiology of Reproduction".
Vita.
Physical Description:xiii, 103 leaves : illustrations ; 28 cm.
Also available online.
Issued also on microfiche from Lange Micrographics.
Bibliography:Includes bibliographical references: pages 83-100.