The present study was designed to assess progesterone profiles at the secreted (caudal vena cava) and circulating levels (jugular vein) and luteinizing hormone (LH) secretion pattern in lactating and non-lactating cows with reference to feeding. Four lactating and four non-lactating cycling Holstein cows were examined. Blood samples were collected simultaneously from the caudal vena cava (via a...

One critical determinant of fertility is the establishment and maintenance of pregnancy after insemination or embryo transfer. Pregnancy success is low in lactating dairy cows. Reduced fertility of the dairy female is only expressed in the lactational state but the magnitude of depression of fertility is not related to milk yield. Pregnancy failure occurs throughout gestation with the greatest ...

We measured daily energy expenditure (DEE) and water turnover rates in lactating and non-lactating short beaked echidnas (Tachyglossus aculeatus) using the doubly labelled water technique during the lactation period in spring. Reproductively inactive echidnas were on average significantly heavier (median: 3354 g; range: 2929-3780 g; N=4) than lactating females (median: 2695 g; range: 2690-2715 ...

Introduction: Pheromones play a great role in the reproductive and social behavior of animals. The main sources of pheromones are urine and paracrine secretions. Through the neuroendocrine system, prolactin is a safe parameter to measure and compare the effects of pheromones on the sexual, maternal and also lactating behavior. Methods: Female rats were divided into 19 groups (n=8). To measur...

Introduction: Different factors affect lactating mothers' desires for choosing a contraceptive method in postpartum period. For example, the role of family planning education is worth to mention. The aim of this research was to determine the relationship between familily planning education during pregnancy and at postnatal ward, and lactating mothers' desires for choosing a contraceptive method...

PURPOSE to evaluate changes in the nutritional status of lactating adolescents in different postpartum weeks. METHOD this is an analytical, observational, longitudinal study. Lactating adolescents were followed-up from the 5th to the 15th postpartum week (PPW). The nutritional status was evaluated in the 5th, 10th and 15th PPW by the Body Mass Index (BMI/age). A colorimetric method was used t...

BACKGROUND In rats, it has been observed that treatment with activators of peroxisome proliferator-activated receptor α (PPARα) disturbs metabolic adaptations during lactation, which in turn lead to a reduction of milk fat content and gains of litters during the suckling period. It has not yet been investigated whether agonists of PPARα are impairing milk production of lactating sows in a simil...

We compared weights and hematological profiles of adult (greater than 3-yr-old) female black bears (Ursus americanus) during hibernation (after 8 January). We handled 28 bears one to four times (total of 47) over 4 yr of varying mast and berry production. Mean weight of lactating bears was greater (P less than 0.0001) than that of non-lactating females. White blood cells (P less than 0.05) and ...

Species may become obligate cooperative breeders when parents are unable to raise their offspring unassisted. We measured the daily energy expenditure of mothers, helpers and offspring during peak lactation in cooperatively breeding meerkats Suricata suricatta using the doubly labelled water technique. Lactating mothers expended more energy per day than allo-lactating subordinate females, non-l...

The plasma LH concentration in ovariectomized lactating rats is low for 14 days postpartum, while the prolactin concentration is high during this period. We examined the effect of the inhibition of increased prolactin secretion with bromocriptine (CB-154) on the LH secretion in lactating rats ovariectomized on day 2 (day 0 = day of parturition). Blood samples were collected through an indwellin...