Augmented Hypothalamic Corticotrophin-Releasing Hormone mRNA and Corticosterone Responses to Stress in Adult Rats Exposed to Perinatal Hypoxia

Stressful events before or just after parturition alter the subsequent phenotypical response to stress in a general process termed programming. Hypoxia during the period before and during parturition, and in the postnatal period, is one of the most common causes of perinatal distress, morbidity, and mortality. We have found that perinatal hypoxia (prenatal day 19 to postnatal day 14) augmented the corticosterone response to stress and increased basal corticotrophin-releasing hormone (CRH) mRNA levels in the parvocellular portion of the paraventricular nucleus (PVN) in 6-month-old rats. There was no effect on the levels of hypothalamic parvocellular PVN vasopressin mRNA, anterior pituitary pro-opiomelanocortin or CRH receptor-1 mRNA, or hippocampus glucocorticoid receptor mRNA. We conclude that hypoxia spanning the period just before and for several weeks after parturition programmes the hypothalamic-pituitary-adrenal axis to hyper-respond to acute stress in adulthood, probably as a result of drive from the parvocellular CRH neurones

Predicting the Onset of Parturition by Determining Calcium in Prepartum Milk of Sheep

Multiple methods of pregnancy detection can be used in sheep production. The gestation period for sheep is usually between 144 and 150 days; however, depending on the breed and age of the ewes, this number can vary. A breeding marker, such as a breeding crayon, is used to detect when the ewe is bred by the ram, and the date the ewe will lamb is typically calculated based on an average 145-day gestation. Unfortunately, this method provides only a rough estimate of when the ewe could lamb. In addition, because sheep routinely give birth to multiples (twins, triplets, and, sometimes, quadruplets), ewes are renowned for dystocia; thus, the ability to pinpoint the time of parturition to a 24-hour, rather than a five-day, window would enable sheep producers to be prepared for any difficulties, thereby reducing newborn lamb mortality. In horses, the time of parturition can be detected within 24 to 48 hours by measuring calcium concentrations in prepartum milk using the Chemetrics K-1700 testing system. Therefore, the objective of this research was to test the effectiveness of measuring calcium concentrations in prepartum ewe’s milk to predict time of parturition in pregnant ewes. The study was designed to collect 10 to 20 mL of ewe’s milk twice daily, beginning four days before the calculated date of parturition until lambing. Because the Chemetrics K-1700 testing system is a rapid-test, milk calcium concentrations will be determined within minutes of hand-milking each ewe. It is standard practice to collect “extra” colostrum for orphaned or sickly lambs roughly 12 hours postpartum and after the newborn lamb(s) have ingested sufficient quantities of their mother’s colostrum and establish their maternal bonds. Therefore, at approximately 12 hours postpartum, an approximate 25-mL sample of colostrum was collected to measure the immunoglobulin quality of the colostrum using three methods (Colostrum Refractometer, Antifreeze tester, and Equine Colostrometer. Unfortunately, a large enough sample size was not collected to accurately analyze the milk samples using the Chemetrics K-1700. When we analyzed the calcium levels in the colostrum, we found that the colostrum quality was similar using the Anti-freeze tester to that of the Colostrum Refractometer, and was significantly different than the Equine Colostrometer. The Anti-freeze tester was also more highly correlated to the Colostrum Refractometer than that of the Equine Colostrometer. Keywords: sheep, colostrum, immunoglobulin quality, mammary secretion

The effects of strain, reproductive condition, and strain of placenta donor on placentophagia in nonpregnant mice

The effects on placentophagia of strain, reproductive condition, and strain of placenta donor were observed in nonpregnant mice. Mice of the C57BL/6By and BALB/cBy strains were exposed to placentas of either strain after either no previous parturitional experience, one parturitional experience without nursing experience, or one parturitional experience with nursing experience. There was a significant effect of strain, a significant effect of reproductive condition, but no significant effect of strain of placenta donor. There was a significant interaction between strain and reproductive condition, but no significant interactions with placenta strain. It was inferred that the ability of a mouse to acquire and utilize relevant stimuli during and after parturition, in order to produce an emancipation of placentophagia from the physiological controls associated with parturition, is influenced by genotype

Evaluation of L-selectin expression and assessment of protein tyrosine phosphorylation in bovine polymorphonuclear neutrophil leukocytes around parturition.

Impaired polymorphonuclear neutrophil leukocyte (PMN) function around parturition has been associated with increased clinical mastitis in dairy cows. Rolling and attachment of PMN to the endothelium is the first step in the recruitment process and is accomplished by interaction between L-selectin on PMN and its ligand on endothelial cells. Furthermore, tyrosine phosphorylation is involved in the initiation of many PMN functions. The objective of this work was to determine changes in expression of L-selectin and tyrosine phosphorylation in the perinatal period. Eight clinically healthy Holstein cows were used as PMN donors at d-21, -14, -7,0 (calving), +1, +2, +7, +14, +28. Evaluation of L-selectin expression was carried out on activated and resting PMN. Anti-bovine L-selectin monoclonal antibody (MAB) and flow cytometric analysis were used to measure the percentage of PMN fluorescing and receptor expression (log mean fluorescent channel, LMFC). Activated and resting PMN showed similar trends in % PMN fluorescence and LMFC. The percentage of PMN fluorescing tended to decrease at parturition, followed by a significant increase at d +14 and +28 (P <0.02). For LMFC a decrease was observed on d +1 followed by an increase through d +28 (P < 0.01). Protein tyrosine phosphorylation of lysates prepared from PMN isolated throughout the study was detected by electrophoresis and western blotting using anti-phosphotyrosine MAB. Several protein bands were tyrosine phosphorylated. Two of these bands (42-44 kDa and 90 kDa) varied in intensity over time. The intensity of the 42-44 kDa band gradually increased from d -7, peaked at d +7 (P < 0.03), and steadily decreased to d +28 (P < 0.02). Antibody to activated mitogen protein kinase reacted with the 42-44 kDa band. Reduced PMN function during the periparturient period could be related to reduced L-selectin adhesion molecules on the cell surface, and to modulation in the phosphorylation of functionally important molecules

Hypotalamus-hypofys-binjurebarksaxeln och perinatal behandling av prematurföl

The danger and vulnerability associated with a preterm birth seem to be closely correlated with a dysfunction of the fetal hypothalamic-pituitary-adrenal (HPA) axis, whose maturation in the foal is without a doubt as delicate as it is important. Not only is this endocrine cascade vital for the foal in order to cope with neonatal stress, it also appears to be fundamental for the final fetal intrauterine maturation, as well as for the onset of foaling. Equine gestation exhibits some rather unique features, indicating a somewhat different significance of the endocrine changes associated with HPA maturation, compared to many other species. This hormonal cascade is rapid and confined to a narrow time during late gestation in the horse, and the risk of the foal completely missing it therefore becomes prominent. Induced parturition in the mare may be operated through uterotonic agents, which occasionally bring about premature foals. Desirable seems the ability to initiate equine labour while simultaneously enhancing fetal HPA maturation, as in humans and ruminants through perinatal glucocorticoid administration. However, similar treatment in the horse has resulted in various, sometimes fatal, outcomes. In the light of the distinctive features of equine gestation, difficulties are encountered following such administration of glucocorticoids and ACTH. Favourable results have however also been displayed in the horse, motivating attempts to overcome the associated obstacles. To ensure a successful therapy, increased knowledge about the endocrinology of equine gestation will be necessary.En för tidig födsel innebär en väldig fara för den nyfödda individen. En bidragande orsak är ofta en bristfällig hypotalamus-hypofys-binjurebarksaxel, vars utveckling ter sig lika känslig som betydelsefull för ett föl. Utöver förmågan att hantera neonatal stress, förefaller denna endokrina kaskad vara av yttersta vikt för den slutliga intrauterina fetala utvecklingen, liksom för initieringen av fölning. Hästens dräktighet skiljer sig något från många andra djurslags, och betydelsen av de endokrina förändringarna associerade med HPA-axelns mognad förefaller något annorlunda. Den hormonella kaskaden är hastig och begränsad till en kort tidsperiod sent under hästens dräktighet, vilket ökar risken för att fölet helt missar denna. Fölning kan sättas igång artificiellt med hjälp av uterotona preparat, vilka dock kan associeras med födseln av underutvecklade individer. Fördelaktigt vore således att parallellt kunna initiera fölning och stimulera den fetala HPA-utvecklingen, vilket hos idisslare och människa kan åstadkommas med hjälp av perinatal administrering av glukokortikoider. Liknande behandling av häst har undersökts men med varierande, ibland fatala, resultat. Då hästens dräktighet innefattar dessa specifika karaktärsdrag, uppstår svårigheter vid administrering av glukokortikoider och ACTH. Vissa studier har dock uppvisat lyckade resultat hos häst, vilket motiverar eventuella försök till att lösa dessa problem. Nödvändig är således utökad kunskap om endokrinologin bakom ekvin dräktighet, innan dylik behandling kan bli aktuell

Immune cells and preterm labour:do invariant NKT cells hold the key?

We have developed our original made-to-measure (M2M) algorithm, PRIMAL, with the aim of modelling the Galactic disc from upcoming Gaia data. From a Milky Way like N-body disc galaxy simulation, we have created mock Gaia data using M0III stars as tracers, taking into account extinction and the expected Gaia errors. In PRIMAL, observables calculated from the N-body model are compared with the target stars, at the position of the target stars. Using PRIMAL, the masses of the N-body model particles are changed to reproduce the target mock data, and the gravitational potential is automatically adjusted by the changing mass of the model particles. We have also adopted a new resampling scheme for the model particles to keep the mass resolution of the N-body model relatively constant. We have applied PRIMAL to this mock Gaia data and we show that PRIMAL can recover the structure and kinematics of a Milky Way like barred spiral disc, along with the apparent bar structure and pattern speed of the bar despite the galactic extinction and the observational errors

Cow serum and colostrum immunoglobulin (IgG1) concentration of five suckler cow breed types and subsequent immune status of their calves

peer-reviewedB. Murphy would like to gratefully acknowledge receipt of a Walsh Fellowship provided by Teagasc.The objective of this study was to determine the effect of cow breed type on (a) cow serum and colostrum immunoglobulin (IgG1) concentrations and (b) subsequent calf serum IgG1 concentration and zinc sulphate turbidity (ZST) units. Five cow breed types were examined: LF (Limousin × Friesian), LLF (Limousin × (Limousin × Friesian)), L (Limousin), C (Charolais) and SLF (Simmental × (Limousin × Friesian)). Three blood samples were taken by jugular venipuncture from the cows at approximately 90, 60 and 30 days pre partum, at parturition and at 15 days or more post partum and from the calves at 48 (40 to 56) h post partum. Prior to suckling a 20 ml sample of colostrum was obtained. Milk yield was estimated using the weigh-suckleweigh technique. The decrease in serum IgG1 concentration in cows between 90 days pre partum and parturition was greater (P < 0.01) for LF cows than all other breed types, except SLF. There was no difference between LLF, L, C and SLF cows. There was no effect of cow breed type on colostrum IgG1 concentration. Milk yield was higher (P < 0.001) for LF cows than all other breed types, while that of SLF was higher than the three remaining breed types, which were similar. Calf serum IgG1 concentration and ZST units were higher (P < 0.01) for the progeny of LF cows than all others except SLF. There was no difference between the progeny of LLF, L, C and SLF cows. Calf serum IgG1 was affected by cow breed type and showed a positive relationship with cow serum IgG1 decreases in late pregnancy

Effects of maternal subnutrition during early pregnancy on cow hematological profiles and offspring physiology and vitality in two beef breeds

This experiment evaluated the effects of subnutrition during early gestation on hematology in cows (Bos Taurus) and on hematological, metabolic, endocrine, and vitality parameters in their calves. Parda de Montaña and Pirenaica dams were inseminated and assigned to either a control (CONTROL, 100% requirements) or a nutrient‐restricted group (SUBNUT, 65%) during the first third of gestation. Dam blood samples were collected on days 20 and 253 of gestation, and calf samples were obtained during the first days of life. Pirenaica dams presented higher red series parameters than Parda de Montaña dams, both in the first and the last months of gestation. During early pregnancy, granulocyte numbers and mean corpuscular hemoglobin were lower in Pirenaica‐SUBNUT than in Pirenaica‐CONTROL cows. Calves from the SUBNUT cows did not show a physiological reduction in red series values in early life, suggesting later maturation of the hematopoietic system. Poor maternal nutrition affected calf endocrine parameters. Newborns from dystocic parturitions showed lower NEFA concentrations and weaker vitality responses. In conclusion, maternal nutrition had short‐term effects on cow hematology, Pirenaica cows showing a higher susceptibility to undernutrition; and a long‐term effect on their offspring endocrinology, SUBNUT newborns showing lower levels of IGF‐1 and higher levels of cortisol.This work was supported by the Spanish Ministry of Economy and Business and the European Union Regional Development Funds (INIA RTA 2013‐00059‐C02 and INIA RZP 2015‐001) and the Government of Aragon under the Grant Research Group Funds (A14_17R). A. Noya received a PhD grant from INIA‐Government of Aragon