Search

Background: Perinatal mortality may vary between herds, but the cost of deaths are always higher than value of the calf. When diagnosing the cause of a calf's death it is important to determine when it occurred, before or after calving. Metabolomics is widely used to identify many human diseases, but quite rarely applied in veterinary science. The aim of this study was to compare the metabolic profiles of calves with different times of death and those of calves born alive. Into the study, twenty one healthy controls (singleton, normal assisted calving, born alive) and 75 stillborn (SB) calves (with a gestation length of ≥260 days, SB, or dead within 6 h of birth) were enrolled. Plasma and urine from SB and control calves were investigated by proton nuclear magnetic resonance based metabolomic methods. SB calves were divided into four PMI groups. One PMI group included calves that died after calving and the other groups - three comprised in utero deaths, based on pathophysiological changes (lung inflation, autolysis in internal organs, hemoglobin imbibition in the pleura and aortic arch). Partial Least Squares - Discriminant Analysis models based on plasma metabolites were calculated, reflecting assumed data clustering., Results: Twenty six metabolites in plasma and 29 in urine changed significantly with PMI according to one way analysis of variance. Half the metabolites in plasma and the majority in urine increased with PMI. Six metabolites increased simultaneously in plasma and urine: acetate, sn-glycero-3-phosphocholine (GPC), leucine, valine, creatine, and alanine., Conclusions: Post-mortem changes in calves were associated with molecular variations in blood plasma and urine, showing the greatest differences for the group in which the post-mortem pathological changes were the most advanced. The results of the study show that evaluation of calf plasma or urine may be used as a diagnostic method for the determination of the PMI. Moreover, the metabolites, which unambiguously increased or decreased, can be used as potential biomarkers of PMI.

Urinary protein excretion occurs in neonates of many animal species, as well as in human neonates. However, the incidence, dynamics, and mechanism of proteinuria have not been unambiguously explained. The aims of this study were to investigate into excretion of selected protein fractions of molecular weight less than 69 kDa (LMW), evaluation of intensity and dynamics of changes during the first month of kids' life, and an attempt to explain the causes of neonatal proteinuria. The analysis were carried out on 16 kids of White Improved goats, over the period from birth until 30 days of age, using clearance methods. Urine proteins were separated electrophoretically (SDSPAGE), and their concentration and percentage content was determined by densitometric method with the use of archiving and image analysis software. The proteins found in the urine were grouped as HMW, LMW and albumin. For six fractions of LMW proteins, excretion rates and percentage content of the urinary total LMW protein pool were calculated. It has been demonstrated that neonatal proteinuria in goat kids is associated with a high level of excretion of proteins of lower molecular weight than albumin (69 kDa). A strong dynamics of changes in excretion of particular LMW protein fractions with age was observed, which may imply not only an increased permeability of glomerular filtration barrier, especially over the first days of life, but also a selectivity of reabsorption mechanisms in the nephrons. An increased permeability of glomerular filtration barrier for proteins during the first days of life may represent the adaptive mechanism for removal of protein excess from the organism. The urinary LMW protein pool may also contain proteins resulting from the hydrolysis in the tubular cells.

Exosomes are small membrane vesicles that are secreted from a variety of cell types into various body fluids including the blood and urine. These vesicles are thought to play a role in cell-cell interactions. CD24 is a small but extensively glycosylated protein linked to the cell surface by means of a glycosyl-phosphatidylinositol anchor. In this study we found that CD24 is present in membrane vesicles characterized as exosomes that were isolated from the urine of normal individuals. CD24 was expressed by both tubule cells and podocytes and treatment of the latter with a cholesterol-extracting agent, but not with a calcium ionophore, caused the release of CD24-containing exosomes. Using CD24 as a marker, we found exosomes in the urine of newborn infants and in the amniotic fluid of pregnant women with similar findings made in mice. Interestingly, studies with CD24 knockout mice showed that the exosomes are released from the fetus but not from the mother; however, exosome release was similar from both the knockout and the wild-type mice. This indicates that CD24 is not essential for exosome formation or release but may be a convenient exosome marker. Our studies suggest that exosomal secretion from the embryonic kidney could play a biological role at the fetal-maternal interphase.

Objective: To determine the effects of a 24-hour infusion of an isotonic electrolyte replacement fluid (IERF) on weight, serum and urine electrolyte concentrations, and other clinicopathologic variables in healthy neonatal foals., Animals: 4 healthy 4-day-old foals., Design: Prospective study., Procedure: An IERF was administered to each foal at an estimated rate of 80 mL/kg/d (36.4 mL/lb/d) for 24 hours. Body weight was measured before and after the infusion period. Urine was collected via catheter during 4-hour periods; blood samples were collected at 4-hour intervals. Variables including urine production; urine and serum osmolalities; sodium, potassium, and chloride concentrations in urine and serum; urine and serum creatinine concentrations; urine osmolality-to-serum osmolality ratio (OsmR); transtubular potassium gradient (TTKG); and percentage creatinine clearance (Cr(cl)) of electrolytes were recorded at 0, 4, 8, 12, 16, 20, and 24 hours during the infusion period. Immediately after the study period, net fluid and whole-body electrolyte changes from baseline values were calculated., Results: Compared with baseline values, urine and serum sodium and chloride serum concentrations, urine and serum osmolalities, OsmR, and percentage Cr(cl) of sodium and chloride were significantly increased at various time points during the infusion; urine production did not change significantly. After 24 hours, weight, TTKG, serum creatinine concentration, and whole-body potassium had significantly decreased from baseline values., Conclusions and Clinical Relevance: Results suggest that administration of an IERF containing a physiologic concentration of sodium may not be appropriate for use in neonatal foals that require maintenance fluid therapy.

Domoic acid (DA), produced by the diatom genus Pseudo-nitzschia, is a glutamate analog and a neurotoxin in humans. During diatom blooms, DA can contaminate filter-feeding organisms, such as shellfish, and can be transferred by ingestion to higher trophic levels. Several intoxication events involving both humans and various marine mammals have been attributed to DA. Affected organisms show neurological symptoms such as seizures, ataxia, headweaving, and stereotypic scratching, as well as prolonged deficits in memory and learning. Neonatal animals have been shown to be substantially more sensitive to DA than adults. However, it has not been demonstrated whether DA can be transferred to nursing young from DA-exposed mothers. This study demonstrates transfer of DA from spiked milk (0.3 and 1.0 mg/kg) to the plasma of nursing neonatal rats and an overall longer DA retention in milk than in plasma after 8 hr in exposed dams. DA was detectable in milk up to 24 hr after exposure (1.0 mg/kg) of the mothers, although the amount of DA transferred to milk after exposure was not sufficient to cause acute symptoms in neonates.

Little information is available on the prevalence of retrovirus infections in populations of non-human primates living in their natural habitats. To gain such information, methods were developed to detect antibodies to simian T-lymphotropic virus type 1 (STLV-1) in urine from wild chimpanzees. Samples from more than 74 chimpanzees living in three communities in the Taï National Park, Côte d'Ivoire, were analysed. The prevalence of STLV-1 antibodies in adults and adolescents was significantly higher (35/49, 71.4 %) than that in infant and juvenile chimpanzees (3/31, 9.7 %).

Background: Although hypercalciuria has the same prevalence in children as adults, children rarely develop renal stones. This may be explained by a greater urinary citrate excretion in infants compared with adults. The present study examines the renal excretion of citrate and renal cortical citrate metabolism in infant and adult rats., Methods: Adult male and newly weaned infant rats were acclimated to metabolic cages and fed synthetic diets. Urine was collected after two days, and renal cortical citrate metabolism was assayed., Results: Infant rats had a lower plasma [HCO3-] and higher plasma [K+] and had a fourfold higher urinary citrate:creatinine ratio and a twofold higher concentration of citrate in their urine compared with adult rats. This higher urinary citrate excretion was not due to a difference in renal proximal tubular Na/citrate cotransporter activity, nor renal cortical citrate synthase or ATP citrate lyase activities in infants as compared with adults. However, infant rat kidneys had significantly lower mitochondrial aconitase (m-aconitase) activity. Renal cortical citrate concentrations were comparable in infant and adult rats. Manipulation of plasma [K+] to adult levels did not affect the higher urinary citrate excretion in infant rats., Conclusions: Urinary citrate excretion in infant rats is greater than in adults but does not parallel tissue [citrate]. Thus, this higher urinary citrate is likely due to maturational differences in the proximal tubule, other than Na/citrate cotransport, that directly affect citrate transport.

Objective: To establish reference values for urinary diagnostic indices in healthy calves from birth to 90 days of age., Design: Prospective field trial., Animals: 12 Holstein heifer calves., Procedure: Urine and serum samples were collected daily for the first 5 days after birth, then weekly until calves were 90 days old. Urine:serum creatinine ratio, urine:serum urea nitrogen ratio, urine:serum osmolality ratio, fractional clearances of sodium and inorganic phosphate, and urine gamma-glutamyltransferase activity were measured. Data were grouped by age of calves at the time of sample collection: 1 to 5 days old (neonatal period), 7 to 27 days old (suckling period), and 28 to 90 days old (weanling period)., Results: Mean urine:serum creatinine, urea nitrogen, and osmolality ratios were significantly higher during the weanling period than during the other 2 periods. There were no significant differences in mean fractional clearances of sodium among age periods., Clinical Implications: Urinary diagnostic indices calculated for these healthy calves may be used as reference values for early recognition of renal damage or renal failure.

Urine (U) and serum (S) were obtained every 2 hours during a 12- or 24-hour period from eight healthy 96-hour-old pony or horse foals. Dams' milk samples were obtained concurrently. Urine volume was measured during this 12- or 24-hour period. The mean amount of urine produced was 148 +/- 20 ml/kg/day. Baseline urinalyses were evaluated on all foals at two days of age, before any manipulation. Urine generally was dilute (less than 1.008) but the specific gravity was as high as 1.027 in one normal foal. Continuous (12 or 24 hour) urinary catheterization resulted in bacteriuria but not white blood cells in the urine. Prolonged catheterization did not cause foals to become febrile or exhibit clinical signs of cystitis or other illness. Urinary electrolyte excretion, urinary electrolyte clearances, and fractional electrolyte excretions (FE) were measured. When compared with normal values reported in adult horses, excretion, clearance, and FE were similar for sodium (Na) but higher for potassium (K), phosphorus (P), and calcium (Ca). There were no significant differences between data collected during different time periods, and it was concluded that the use of single sample urine/serum estimates of fractional excretion in the neonatal foal was an appropriate indicator of the renal handling of electrolytes, and when viewed in conjunction with urinalysis and other serum parameters, a valuable aid to evaluating renal function.

The factors associated with increased renal excretion of vasopressin (VP) were examined in the hypoxic fetus and newborn. Studies were conducted on six chronically instrumented fetal (117-136 days gestation) and seven newborn lambs (2-6-day-old). Hypoxia was produced by administration of 10% oxygen to the ewe or neonate for 30 min. This procedure caused a 50% reduction in PaO2, no significant change in pHa in either fetus or neonate and a slight fall in PaCO2. Hypoxia caused an increase in VP concentrations in plasma from 1.3 +/- 0.53 to 46.4 +/- 4.71 pg/ml in the fetus and from 5.9 +/- 2.80 to 50.2 +/- 26.68 pg/ml in the neonate. After hypoxia there was a fall in urine output from 0.27 +/- 0.045 to 0.17 +/- 0.046 ml/(min X kg) in the fetus and from 0.15 +/- 0.033 to 0.09 +/- 0.022 ml/(min X kg) in the newborn. The corresponding values for urine osmolality were the following: 168 +/- 30.8 to 325 +/- 30.6 mOsm/kg in the fetus and 388 +/- 65.4 to 523 +/- 51.8 mOsm/kg in the newborn. VP concentration in urine increased from 13 +/- 9.4 to a maximum of 176 +/- 32.4 pg/ml after 30 min of recovery in the fetus and 39 +/- 4.6 to 278 +/- 132.5 pg/ml after 1 h of recovery in the newborn. These levels remained high for at least 1 h after the end of hypoxia. There was a good linear correlation between plasma VP levels and the corresponding urine levels and excretion rates in both the fetus and newborn.(ABSTRACT TRUNCATED AT 250 WORDS)

Using a specific and sensitive epidermal growth factor (EGF) radioimmunoassay, we have shown measurable quantities of EGF in mouse urine during the neonatal period. Sephadex G-50 column chromatography demonstrated the presence of a single immunoreactive component at the position defined by standard EGF (mol wt 6045). Comparison of urine urea nitrogen and urine EGF levels in neonatal and adult mice showed adult values to be 3- and 16-fold higher, respectively. Kidney weights relative to body weight were similar in newborn and adult animals while kidney EGF concentration per mg protein was 2.5-fold higher in the adult. The relative submandibular gland (SMG) weight was slightly higher in adult female mice than in the newborn, whereas SMG-EGF concentration was 15,000-fold higher in the adult than in the newborn. Thyroxine administration to neonatal mice from day 0 to day 6 increased urine EGF concentration 7-fold compared to control pups. Though the hormone treatment elicited a significant increase in relative SMG weight, its EGF concentration like that of the kidneys remained unchanged. The results suggest that urine EGF is subject to thyroid hormone modulation in newborn animals and that the changes in urine EGF concentration are independent of changes in SMG and renal EGF levels.

Recent studies have shown that immature rats display a diminished sensitivity to the phosphaturic effects of parathyroid hormone (PTH), and that the responsiveness to PTH increases with age. The attenuated phosphaturia may reflect an inability of the neonate to respond to the hormone because of functional immaturity of the developing kidney. Alternatively, PTH may actually inhibit tubular phosphate reabsorption in the neonate but, due to other phosphate conservation mechanisms, no phosphaturia occurs. Our objective was to determine whether a phosphaturic response to PTH would be elicited in immature rats during infusion of moderate amounts of phosphate (Pi). Clearance experiments were performed on 26 acutely thyroparathyroidectomized immature Wistar rats (3-5 wk of age) fed a normal Pi diet (0.63%). In response to infusion of either Pi (1 mumol/min.100 g) (group I) or PTH (8.3 ng/min.100 g) (group II) alone, the fractional excretion of phosphate rose minimally (from 0.01 +/- 0.01% to 4.9 +/- 1.9% and from 0.12 +/- 0.12% to 2.9 +/- 1.4% for groups I and II, respectively). However, when Pi and PTH were combined either Pi first followed by PTH (group III) or PTH first followed by Pi (group IV), the fractional excretion of Pi rose dramatically (from 0.01 +/- 0.01 to 21.8 +/- 3.5% and from 0.04 +/- 0.04 to 27.7 +/- 3.3% for groups III and IV, respectively). A significant increase in urinary cAMP excretion occurred during infusion of PTH even when Pi excretion was minimal, but there was no further increase in urinary cAMP during the combined infusion of Pi and PTH.(ABSTRACT TRUNCATED AT 250 WORDS)