2011 (SBTE) 25th Annual Meeting Proceedings - International ...

Acta Scientiae Veterinariae, 2011. 39(Suppl 1): Abstracts - 25th Annual Meeting SBTE-Brazil. August 2011.
A083 FTAI, FTET AND AI
EVAL
ALUATION OF THE EFFECTS OF HEAT STRESS ON REPRODUCTIVE PERFORMANCE OF NELORE HEIFERS DURING THE
BREEDING SEASON
Milt
ilton Matur
turana Filho
1 , Namíbia Apar
parecida
Teix
eixeir
eira 2 , Saar
aara a Car
arolina Scolar
olari 3 , Aline Kehrle
4 , Patrícia Helena Paiv
aiva a Migue
iguez 5 , Thiago San
antin
6 & Ed Hoffman
Madureira 7
1,2,3,4,5,6,7
USP, PIRASSUNUNGA, SP, BRAZIL. 2,3 USP, PIRASSUNUNGA, SP, BRAZIL.
Many studies involving the effects of heat stress have been developed in dairy cattle, but a few has been discussed this issue in
slaughtering cattle. The aim of this study was to evaluate the effects of heat stress on reproductive performance of Bos indicus beef heifers during
the breeding season. The experiment was conducted from November 2009 to January 2010. We had been using 102 heifers of Nellore, cyclic,
with 24 months. To TAI was used semen of one bull of the Nelore breed. The animals were maintained on Brachiaria brizantha, with water and
mineralization ad libitum. At the beginning of the protocol were evaluated parameters of body condition score (BCS, also evaluated at TAI and
pregnancy diagnosis (PD). Rectal temperature (RT) and temperature and humidity index (THI) were evaluated at TAI. The THI is calculated from
the model defined by Thom (1959) were: THI (0.8 x T ° C + (RH (%) / 100) x (T-14, 4) + 46.4) where: T = temperature °C, RH = relative
humidity. The climate data used were obtained from the Meteorological Station of USP. The following hormonal protocol was used: D0 =
implant insertion vaginal P4 + application of 2 mg EB, D8 = implant removal vaginal P4 + application of 300 IU of eCG, according to the body
score + 25 mg D-Cloprostenol; application 1mg D9 = BE; D10 = TAI. The heifers were retrospectively separated into groups according to the
THI at the time of TAI, which is equivalent to: Class 1 (69-74), Class 2 (75-79) and Class 3 (80-84), the latter being characterized by conditions
more extreme temperature and humidity. The pregnancy rate (PR) was evaluated by ultrasonography (Aloka 500 with 5.0 MHz linear probe) on
days 30, 60 and 90 days after TAI, and separated according to the THI and RT classes. The data were subjected to frequency analysis using
PROC FREQ and logistic regression analysis by PROC LOGISTIC, using the Statistical Analysis System (SAS, 9.2) by adopting a significance
level of 5%. The rate of pregnant at 30 days of the heifers which were in the condition for a THI 1 was 57.8% (n = 19), for heifers 2 of THI was
57.7% (n = 38) and THI was 3 28.9% (n = 45). So, there was a reduction (P < 0.01) the pregnancy rate for heifers in the third class of THI. Thus,
the fertility of heifers may be affected by the effects of heat stress.
Keywords: heat stress, temperature and humidity index, nelore heifers.
A084 FTAI, FTET AND AI
THE CHARACTERISTICS OF THE FOLICULAR DYNAMICS OVER THE DIAMETER OF THE CORPUS LUTEUM IN
FIXED TIME EMBRYO TRANSFER RECIPIENTS
A n tônio De Lisboa Rib
ibeir
eiro Filho
1 , Br uno Henr
enrique De Ar aújo Andr
ndrade
2 , Tess Picq Coutinho
3 , Leandr
eandro Mour
oureir
eira De Castr
astro
Feitosa 4 , Marcus Vinícius Galvão Loiola 5 , Alexandra Soares Rodrigues 6 , Priscila Assis Ferraz 7 , Marcos Chalhoub 8 , Endrigo Adonis
B r aga De Ar aujo 9 , Sidnei Nunes Oliv
liveir
eira 10 , Mar
arc os Rib
ibeir
eiro 11 & Yeda Fumie
Wa tanabe 12
1,2,3,4,5,6,7,8,9,10
ESCOLA DE MEDICINA VETERINÁRIA - UFBA, SALVADOR, BA, BRAZIL. 3,11 UNIME, LAURO DE FEITAS, BA, BRAZIL. 12 VITROGEN PESQUISA E DESENVOLVIMENTO EM
BIOTECNOLOGIAS DE REPRODUÇÃO LTDA, CRAVINHOS, SP, BRAZIL.
A positive correlation between the preovulatory follicle and the diameter of the corpus luteum (CL) in cows submitted to fixed time
artificial insemination (FTAI) protocols has been verified (Andrade et al., 2011, Congresso Brasileiro de Reprodução Animal 19, 116). Our
objectives were to evaluate the dominant follicle growth characteristics with the diameter of the CL in embryo recipients heifers submitted to
ovulation synchronization protocols. For this purpose 12 Bos taurus taurus x Bos taurus indicus heifers were used. Heifers were treated with
the following protocol: the animals received an intravaginal progesterone device (P4 - CIDR ® , Pfizer, São Paulo, Brazil), 2mg of Estradiol
Benzoate i.m. (EB - Gonadiol ® , Shering-Plough, São Paulo, Brazil) and a part of animals were treated with 250µg of Cloprostenol i.m.
(Sincrocio ® , Ouro-Fino, São Paulo, Brazil) on the day named D0. On day 8 (D8) the P4 was removed followed by the application of 300IU of
eCG (Novormon ® , Shering-Plough, São Paulo, Brazil), 250µg Cloprostenol i.m. The animals had ovulation induced with 1 mg of EB or 1 mg
of Estradiol Cypionate i.m. (ECP ® , Pfizer, São Paulo, Brazil) on day 8 or 1 mg of EB i.m. on Day 9. On D10 the examinations started by
transrectal ultrasound at 6 hour intervals, for the following 70 h in order to follow up on the preovulatory dynamics. The CL diameter was
evaluated by the same technique seven days after the first ultrasound evaluation (D17). The PROC CORR resource from SAS ® software was
used for statistical analysis of the correlation between the results (P < 0.05). The average diameter of the follicles 48h after P4 removal (FOL-
D10), of the preovulatory follicle (FOLPRE) and of the CL were 10.71±3.44, 12.53±2.95 e 17.55±1.86mm, respectively. The diameter of the
FOL-D10 presented strong negative correlation with the growth rate (R=0.70, P = 0.02) and strong positive correlation with the preovulatory
diameter (R=0.84, P = 0.0007). Although, the diameter of the preovulatory follicle did not present correlation to the CL diameter. These results
show that the smaller the diameter of the FOL-D10, the larger its growth rate. Nevertheless, the diameter of the FOLPRE was not correlated with
the diameter of the CL, making it necessary that more studies are developed to elucidate these and other questions exposed in this study.
Keywords: cl, ftet, recipients.
s378