Effect of the periparturient period on serum lipid and cholesterol lipoprotein concentrations in goats (Capra hircus).

Blood samples were taken from 12 goats during the periparturient period (4 and 1 weeks before and 2, 10 and 30 days after delivery), and from 10 nonpregnant goats. The following variables were determined: total lipids (TL), triacylglycerol (TG), total cholesterol (TCH) and high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol fractions. One week before delivery TL (2.32 ± 0.12 g/l, P ≤ 0.05), TG (0.32 ± 0.16 mmol/l, P ≤ 0.001) and TCH concentrations (1.65 ± 0.42 mmol/l, P ≤ 0.05) were significantly increased as compared to non-pregnant goats (2.08 ± 0.28 g/l, 0.15 ± 0.05 mmol/l, 1.38 ± 0.19 mmol/l, respectively). After delivery, the concentrations of TL, TG, TCH and HDL decreased significantly. The lowest TG concentration was observed 2 days after delivery (0.18 ± 0.02 mmol/l), while TL (1.73 ± 0.21 g/l), TCH (0.95 ± 0.21 mmol/l) and HDL (0.74 ± 0.16 mmol/l) reached the lowest level 10 days after delivery. Two days after delivery a significant increase of LDL concentration was observed (0.38 ± 0.04 mmol/l); however, ten days after delivery a threefold decrease was shown in the LDL concentration (0.12 ± 0.04 mmol/l). A month after delivery all the variables studied reached levels similar to those measured in non-pregnant goats.

Changes in Adenylate Nucleotides Concentration and Na, K-ATPase Activities in Erythrocytes of Horses in Function of Breed and Sex.

The aim of this study was to examine the relationships between the concentrations of ATP, ADP, AMP (HPLC methods), total nucleotide pool (TAN), adenylate energy charge (AEC) and Na(+), K(+)-ATPase erythrocytic activities (by Choi's method) of horses as a function of breed and sex. The studies were conducted on 54 horses (stallions and mares) of different constitution types: breathing constitution (Wielkopolska and Hanoverian breed) and digestive constitution (Ardenian breed). Horse erythrocytes, independently of examined breed, present low ATP concentration in comparison to other mammal species while retaining relatively high AEC. Erythrocytes of breathing constitution type horses appear to have a more intensive glucose metabolism and a more efficient energetic metabolism when compared to digestive constitution type horses. The conclusions may be proven by significantly higher ATP concentration, higher TAN and significantly higher AEC in breathing constitution type horses compared to the digestive constitution type. Sex does not significantly influence adenine nucleotides concentration in the erythrocytes of the examined horses, however, stallions have slightly higher values in comparison to mares. A positive correlation was found between Na(+), K(+), -ATPase activity, ATP, ADP and AMP concentration and TAN in Wielkopolska and Ardenian breeds, which was not confirmed for the Hanoverian breed.

A review of the renal system and diurnal variations of renal activity in livestock.

Kidneys are the main organs regulating water-electrolyte homeostasis in the body. They are responsible for maintaining the total volume of water and its distribution in particular water spaces, for electrolyte composition of systemic fluids and also for maintaining acid-base balance. These functions are performed by the plasma filtration process in renal glomeruli and the processes of active absorption and secretion in renal tubules, all adjusted to an 'activity-rest' rhythm. These diurnal changes are influenced by a 24-hour cycle of activity of hormones engaged in the regulation of renal activity. Studies on spontaneous rhythms of renal activity have been carried out mainly on humans and laboratory animals, but few studies have been carried out on livestock animals. Moreover, those results cover only some aspects of renal physiology. This review gives an overview of current knowledge concerning renal function and diurnal variations of some renal activity parameters in livestock, providing greater understanding of general chronobiological processes in mammals. Detailed knowledge of these rhythms is useful for clinical, practical and pharmacological purposes, as well as studies on their physical performance.