Mares (n = 77) were evaluated by antral follicle count (AFC) and selected as embryo recipients. Cyclic recipients received embryos between days 4-6 after ovulation. The acyclic recipients received an intramuscular (i.m.) protocol with 5mg of estradiol benzoate (EB) on the day of donor ovulation (D0; D-4 recipient), 3mg of EB on the following day (D1; D-3 recipient), and 3mg of EB (D2; D-2 recipient). Furthermore, 1500mg of progesterone (P4) i.m. given on D0 of the recipient (D4 donor) followed by 1500mg of P4 on the day of ET (D4-6 recipient). On the ET day, the AFC and animals' weight, body condition score (BCS), corpus luteum diameter, age and degree of uterine edema (UE) were measured. Pregnancy was confirmed on days 12 and 30. Low AFC was defined as ≤11 follicles (n = 43 mares) and high AFC as >11 follicles (n = 34 mares). Data were analyzed by a mixed effect model, including AFC group, reproductive seasonality, and season (P ≤ 0.05). UE was influenced (P = 0.05) by reproductive seasonality. The conception rate was higher (P = 0.016) in recipients with low (79.07 %) than high AFC (61.76 %) and higher (P = 0.005) in cyclic (81.40 %) than anestrus (58.82 %) mares. In addition, we observed a tendency (P = 0.06) for the interaction of AFC*reproductive seasonality, showing that high*anoestrus recipients had the lowest conception rate (37.50 %b) compared to high*cyclic (83.33 %a), low*anoestrus (77.78 %a) and low*cyclic (80 %a). The conception rate was higher in cyclic recipients with low AFC. Furthermore, UE was influenced by reproductive seasonality and mares in anestrus showed a higher degree of UE than cyclic mares.

For this study, ½ blood nelore × aberdeen angus heifers (n = 40; 14 months) were divided into two groups: control (n=20; 310 kg) and pró-cio (n=20; 304 kg). for pró-cio group, 20g of homeopathic product (pró-cio®, real h, campo grande, brazil) was supplied together with corn eighteen days prior (d-18) to the beginning of the fixed-time artificial insemination protocol (ftai). on d0, all females received an intravaginal p4 device and 2 mg be. on d5, the afc was assessed by ultrasound and blood was collected for amh dosage. on d8, p4 device was removed; 300 iu ecg, 0.530 mg of cloprostenol sodium and 0.5 mg of ec were administered; an estrus-identifying adhesive was fixed at the tail insertion and the diameter of the dominant follicle (df) was measured. on d10, all heifers were inseminated, estrus manifestation was assessed and the preovulatory follicle (pof) was measured. on d20, the cl area was measured and blood flow was assessed using doppler ultrasound. data were analyzed by student, mann-whitney or friedman test. the rates of heat expression, ovulation, and blood flow score with doppler were analyzed using fisher’s exact test and pregnancy rate by binary logistic regression model (p ≤ 0.05). there was no difference in afc or amh dosage (p > 0.05). pró-cio group had greater diameters of the df (9.94 ± 0.42 mm) and pof (11.61 ± 0.56 mm) than the controls (df: 7.72 ± 0.34 mm and pof: 9.91 ± 0.37 mm), as well a larger cl area (3.26 ± 0.26 versus 2.35 ± 0.16 cm2) and a higher mean cl vascularization score (3.06 versus 2.26; p < 0.05). there was no significant difference (p > 0.05) between estrus manifestation or conception rate for control and pró-cio groups. heifers supplemented with the homeopathic product showed larger follicular diameters at the end of the ftai protocol and cl with better blood flow scores compared to the control group.

The ovarian follicle population is formed by thousands of follicles, preantral and antral, where oocytes are included. During fetal life, the first follicles produced are preantral, and, as they undergo the development process, they reach the final stage of antral follicles, where a cavity/or antrum is developed. All this growth phase is called folliculogenesis, and this chapter will abord the most important aspects of this process. Moreover, not all follicles reach the preovulatory phase and can be fertilized, so we will discuss how reproductive biotechniques can positively influence the fertility of bovine females. We will also discuss the possibility of antral follicle count to influence reproductive performance and the correlation to biotechniques. Finally, we present alternatives on how to improve fertility and productive efficiency in dairy herds.

ABSTRACT Prepubertal Nelore (G-N = 15) and crossbred Nelore x Aberdeen Angus heifers (G-NA = 15) were used for this study. AFC, live weight, body condition score (BCS), ovary and dominant follicle (DF) diameters were determined in each animal. Puberty induction was performed by insertion of a 4th use progesterone device (D0) which was removed on D12. Also, 1 mg estradiol benzoate was administered, and estrus intensity was classified (D12). At D21, the presence and diameter of the corpus luteum (CL) were registered. AFC was highly repeatable, regardless of hormone induction in both G-N (r=0.79) and G-NA (r=0.90). The mean AFC was greater in G-N compared to G-NA (24.2±8.5 vs. 17.7±9.0 follicles). A variation in BCS throughout the study occurred in G-NA, but not in G-N. The average weight gain (AWG) was greater in G-NA compared to G-N (0.69±0.33 vs. 0.40±0.29kg/day). The G-NA resulted in a larger diameter of DF at D12 than G-N (11.6±2.7 vs. 9.3±1.5mm). In conclusion, AFC was greater in Nelore heifers, although in both breeds this count was highly repeatable during puberty induction. Crossbred heifers had greater BCS and AWG with greater diameter of DF, indicating higher precocity when compared to Nelore heifers.

p=0,0004) nesses dois momentos avaliados.A comparação entre a testosterona do primeiro dia e o cortisol antes do treinamento foi negativa assim como a testosterona do segundo dia com o cortisol após treinamento.Conclui-se que houve evidência de estresse após o treinamento sem interferência na produção de testosterona.

O presente relato tem por objetivo reportar o caso de endometrite bacteriana em uma doadora de embrião da raça Quarto de Milha com 12 anos de idade, sem sinal clínico evidente, mas com histórico de falhas reprodutivas há 2 anos. Após tentativas de inseminação artificial com sêmen refrigerado e ausência de gestação, a égua foi submetida a exame ginecológico, seguido de citologia uterina, cultura bacteriana e antibiograma, indicando um quadro de endometrite por Klebsiella sp. sensível à enrofloxacina e ceftiofur. Diante do diagnóstico, iniciou-se tratamento para endometrite bacteriana, o qual se mostrou eficiente, sendo possível a recuperação de um embrião viável que foi transferido com êxito para uma receptora, resultando em prenhez. O presente caso reporta o sucesso no diagnóstico e tratamento de uma égua com infertilidade ocasionada por endometrite subclínica. Destaca-se que, para eficiência terapêutica nas endometrites bacterianas, é fundamental conhecer o patógeno e a sensibilidade aos principais antibióticos. Alguns sinais como acúmulo de líquido intrauterino, presença de edema e secreções vaginais frequentemente acompanham os casos de endometrite, no entanto, a ausência destes sinais não descarta a ocorrência da enfermidade, sendo necessária maior investigação diagnóstica frente ao histórico de infertilidade.