Traditional methods of estrus synchronization developed over the past 60 yr have involved controlling bovine estrous cycle length by administering a progestin and/or regressing the corpus luteum with luteolytic drugs. The synchrony of estrus and timing of ovulation following traditional estrus synchronization treatments has been too variable to allow the transfer of a fresh or frozen/thawed emb...

Estrous synchronization programs provide an organized and efficient approach to administering artificial insemination (AI) and the improvement of reproductive performance. Synchronization programs facilitate AI by altering the length of the estrous cycle and (or) through manipulation of follicular growth, thereby making the occurrence of estrus more predictable or allowing for appointment breed...

The effect of an acute energy deficit on the hormone balance of dominant follicles was studied in six normally-cycling, high-yielding Italian Friesian cows at 60 and 90 days after calving. At 60 days after calving, the cows, which had been fed according to their maintenance and production requirements, were synchronized and follicular fluid was collected from the dominant follicles under ultras...

Girolando (Gir x Holstein) is a very common dairy breed in Brazil because it combines the rusticity of Gir (Bos indicus) with the high milk yield of Holstein (Bos taurus). The ovarian follicular dynamics and hormonal treatments for synchronization of ovulation and timed artificial insemination were studied in Girolando heifers. The injection of a gonadotrophin-releasing hormone (GnRH) agonist w...

Although superstimulatory protocols in cattle are usually initiated during mid-cycle, the elective control follicular wave emergence and ovulation have had a great impact on the application of on-farm embryo transfer. However, the most commonly used approach for the synchronization of follicular wave emergence involves the use of estradiol which cannot be used in many parts of the world. Theref...

the threshold of weak and strong synchronization in a coupled chaotic gaussian map isdemonstrated by using the pyragas’ terminology. however, vieira and lichtenberg have shown that thepyragas’ criteria for weak and strong synchronization cannot be used for all chaotic systems. in this articlewe demonstrated some interesting synchronization behavior of two coupled chaotic systems with some zeroa...

The kallikrein-kinin system (KKS) has been described as an important mediator of physiologic processes. Kallikreins use kininogen (KNG) as substrate to generate bradykinin, the main active peptide of the KKS that acts through two types of receptors, the B(1)R and the B(2)R. The goal of this study was to characterize some components of the KKS in different compartments of the ovary during the bo...