Oxidative stress and acid-base balance during the transition period of neonatal Holstein calves submitted to different calving times and obstetric assistance.

During the neonatal period, constant adaptations to the extrauterine environment are required. These adaptations are made impossible or hindered when unexpected obstetrical events take place. This study aimed to identify clinical changes of vitality, metabolic and acid-base balance, and oxidative stress of newborn calves born to assisted dams that experienced different durations of calving.

Influence of the duration of calving and obstetric assistance on the placental retention index in Holstein dairy cows.

The aim of this study is to evaluate the influence of duration of calving and obstetric assistance on retained placenta incidence of high milk production Holstein cows. Experimental groups were determined according to the duration of the expulsive phase of calving: 2 h (n = 16), 2-4 h (n = 16) and >4 h (n = 12), and additionally allocated in two sub-groups: spontaneous calving (n = 22) and intervention calving (n = 22). Diagnosis of retained placenta was considered with a threshold of 8 h after the expulsive phase.

The influence of the obstetrical condition on canine neonatal pulmonary functional competence.

Objective: To compare the influence of the obstetrical condition on neonatal respiratory performance, to estimate surfactant synthesis through lecithin and sphingomyelin ratio (L/S) in amniotic fluid of pregnant bitches and correlate the L/S with the respiratory condition during the first hour of life.

Design: Prospective randomized study.

Setting: University veterinary teaching hospital and private referral centers.

Immunohistochemical localization of VEGF and its receptors in the corpus luteum of the bitch during diestrus and anestrus.

The corpus luteum (CL) is a temporary endocrine gland, whose life span depends on the interaction of luteotrophic and luteolytic factors. Since development and maintenance of CL is based on angiogenesis, angiogenic growth factors may play a role in CL-function of the bitch, as described for other species. The aim of this study was to detect the presence of the vascular endothelial growth factor (VEGF) system in the bitch CL throughout diestrus and early anestrus.