Hormonal changes during parturition in heifers and goats are related to the phases and severity of labour

Physiological Stress Responses in Cattle Used in the Spanish Rodeo

Certain events can cause distress in cattle. In Spain, there is a sport similar to rodeo called persecution and takedown, in which calves are harassed and knocked down by riders. In this study, the physiological stress response of calves (n = 260) is assessed by measuring hormonal physiological parameters. Salivary samples were collected from Salers (n = 110) and Lidia (n = 150) calves before, during, and after the persecution and takedown event. The hormones epinephrine, cortisol, serotonin, and dopamine were determined in saliva samples using enzyme-immunoassay techniques. The results obtained revealed that epinephrine and cortisol levels increased during the event in Salers calves, with a significant increase (p < 0.05) in the case of epinephrine, although after the event, these values returned to their initial state. Therefore, this sport supposes an assumable punctual stressor stimulus for the animal. In contrast, in Lidia calves, cortisol and epinephrine levels decreased, with a significant decrease (p < 0.05) in the case of cortisol, which may be related to the temperament of this breed and facing a stressful situation in a different manner. This is confirmed by serotonin and dopamine levels that were altered in Lidia calves with respect to the other group studied. In conclusion, the sport of persecution and takedown produces a physiological response of adaptive stress assumable for the animals.

Influences of glyphosate residues and different concentrate feed proportions in dairy cow rations during early gestation on performance, blood parameters, functional properties and DNA damage of blood cells in cows and their offspring

Maternal exposure to various stimuli can influence pre- and postnatal development of the offspring. This potential has been discussed for glyphosate (GLY), active substance in some non-selective herbicides. Accordingly, present study investigated putative effects of GLY residues in rations on cows and their offspring. Dams received either GLY-contaminated (GLY groups) or control (CON groups) rations combined with low (LC groups) or high (HC groups) concentrate feed proportions (CFP) for 16 weeks during mid- and late lactation and early gestation (59±4 days at beginning of GLY exposure; mean±SE). During this feeding trial, average daily GLY exposures of dams were 1.2 (CONLC), 1.1 (CONHC), 112.5 (GLYLC) and 130.3 (GLYHC) μg/kg body weight/d. After a depletion period (107±4 days; mean±SE) and calving, blood samples of dams and their calves were collected (5-345 min after birth) before calves were fed colostrum and analyzed for hematological and clinical-chemical traits, redox parameters, functional properties of leukocytes and DNA damage in leukocytes. No evidence for malformations of newborn calves could be collected. At parturition, most analyzed blood parameters were not affected by dietary treatment of dams during gestation. Significant GLY effects were observed for some traits, e.g. blood non-esterified fatty acids (NEFA) in calves. These deviations of GLY groups from CON groups likely resulted from strong time-dependent responses of NEFA levels within the first 105 minutes after birth and before colostrum intake (Spearman´s rank correlation R = 0.76, p<0.001). Additionally, significant GLY effects did not result in differences in measures that were beyond normally observed ranges questioning a pathological relevance. In summary, no evidence for teratogenic or other clear effects of GLY or CFP on analyzed parameters of dams and their newborn calves could be collected under applied conditions. However, detailed studies including GLY exposure during late and complete gestation period would be needed to rule out teratogenic effects.

Clinical Experiences and Mechanism of Action with the Use of Oxytocin Injection at Parturition in Domestic Animals: Effect on the Myometrium and Fetuses

Oxytocin is a key hormone for parturition and maternal traits in animals. During the peripartum period, the levels of endogenous oxytocin dictate physiological events such as myometrial contractions, prostaglandin production with the subsequent increase in oxytocin receptors, and the promotion of lactation when administered immediately after birth. While this hormone has some benefits regarding these aspects, the exogenous administration of oxytocin has been shown to have detrimental effects on the fetus, such as asphyxia, meconium staining, ruptured umbilical cords, and more dystocia cases in females. This review aims to analyze the main effects of oxytocin on myometrial activity during parturition, and its potential favorable and negative administration effects reflected in the fetus health of domestic animals. In conclusion, it is convenient to know oxytocin's different effects as well as the adequate doses and the proper moment to administrate it, as it can reduce labor duration, but it can also increase dystocia.

Dietary L-Carnitine Affects Leukocyte Count and Function in Dairy Cows Around Parturition

In early lactation, an energy deficit leading to a negative energy balance (NEB) is associated with increased susceptibility to disease and has been shown to be an important factor during transition in dairy cows. L-carnitine as a key factor in the mitochondrial transport of fatty acids and subsequently for β-oxidation and energy release is known to modulate mitochondrial biogenesis and thus influence metabolism and immune system. In the current study, we characterized hematological changes around parturition and investigated the potential effects of dietary L-carnitine supplementation on immune cell functions. For this approach, dairy cows were assigned either to a control (CON, n = 30) or an L-carnitine group [CAR, n = 29, 25 g rumen-protected L-carnitine per cow and day (d)]. Blood samples were taken from d 42 ante partum (ap) until d 110 post-partum (pp), with special focus and frequent sampling from 0.5 to72 h post-calving to clarify the impact of L-carnitine supplementation on leukocyte count, formation of reactive oxygen species (ROS) in polymorphonuclear cells (PMN) and peripheral mononuclear cells (PBMC) and their phagocytosis activity. Blood cortisol concentration and the capacity of PBMC proliferation was also investigated. All populations of leukocytes were changed during the peripartal period, especially granulocytes showed a characteristic increase up to 4 h pp. L-carnitine supplementation resulted in increased levels of eosinophils which was particularly pronounced one day before to 4 h pp, indicating a possible enhanced support for tissue repair and recovery. Non-supplemented cows showed a higher phagocytic activity in PBMC as well as a higher phagocytic capacity of PMN during the most demanding period around parturition, which may relate to a decrease in plasma levels of non-esterified fatty acids reported previously. L-carnitine, on the other hand, led to an increased efficiency to form ROS in stimulated PMN. Finally, a short period around calving proved to be a sensitive period in which L-carnitine administration was effective.

The Onset of Maternal Behavior in Sheep and Goats: Endocrine, Sensory, Neural, and Experiential Mechanisms

In sheep and goats, the onset of maternal behavior at parturition is characterized by a first phase called maternal responsiveness during which the mother is attracted to any newborn. In a second phase, called maternal selectivity, the mother establishes a selective bond with her young so that she only accepts it at suckling. After a description of the behavioral expression of both phases, this chapter reviews the physiological, sensory, and neural mechanisms involved. These two behavioral processes are synchronized with parturition by the vaginocervical stimulation induced by the expulsion of the newborn. Olfactory cues provided by the neonate are involved in maternal responsiveness and selectivity. Oxytocin supported by estrogens is the key factor for maternal responsiveness. The neural network involved in maternal responsiveness is mainly hypothalamic and is different from the circuitry involved in selectivity, which mainly concerns olfactory processing regions. Visual and auditory cues are necessary for offspring recognition at a distance. This multisensory recognition suggests that mothers form a mental image of their young. Maternal experience renders mothers more responsive to maternally relevant physiology and to young-related sensory inputs.

Steroid hormonal endpoints in goats carrying single or twin fetuses reared in semi-extensive systems

The study provides baseline data regarding 17- β -estradiol (E 2 ), progesterone (P 4 ), and cortisol profile of 30 Nicastrese goats during different physiological periods. Animals were evaluated monthly from the pre-mating period (non-pregnant), during pregnancy, and from 30 to 105 d of lactation. The effects of single or twin births and the kid's sex were also considered. Serum E 2 , P 4 , and cortisol concentrations were measured using immunoenzymatic assay kits. The highest concentrations of E 2 and P 4 ( P < 0.0001 ) were found during pregnancy and their lowest values ( P < 0.0001 ) in the non-pregnant period. E 2 was negatively correlated with P 4 ( r = - 0.41 ; P < 0.01 ) during lactation. The mothers with twin kids showed the highest concentration of P 4 ( P < 0.04 ) at >  95-115 d of gestation and the lowest of E 2 ( P < 0.04 ) at >  50-70 d of lactation. Pregnant goats carrying male kid(s) presented the highest E 2 concentrations ( P < 0.02 ) at >  130-150 d of gestation. Different physiological conditions induced a temporal relationship with the endocrine profile in Nicastrese goats. Understanding the effects of single or twin fetuses on the gestation and lactation will also be helpful to improve the managemental approach for the health of mothers and their kids.

Effects of Compost-Bedded Pack Barn on Circulating Cortisol and Beta-Endorphins in Dairy Cows: A Case Study

Simple Summary

Management and housing conditions have been reported to significantly affect the health and welfare of livestock species. Therefore, the adoption of novel, alternative housing systems (such as the compost-bedded pack barn, developed in the USA) requires extensive research to assess the implications for animal welfare. From a general point of view, animal welfare is typically assessed by means of animal-based (such as blood biochemical markers) and resource-based (such as management practices) indicators. Based on such considerations, the present study evaluated the fluctuation of circulating cortisol and beta-endorphins in dairy cows housed in a conventional freestall barn (FB) and in the alternative compost-bedded pack barn (CB). The results obtained suggest that the CB housing system did not elicit significant changes in either blood cortisol or beta-endorphins.

Abstract

The up-to-date literature suggests that the compost-bedded pack barn housing system is capable of remarkably improving productive and reproductive performance, as well as health status and welfare, in dairy cattle. However, there is currently limited knowledge available on the endocrine and biochemical changes in animals housed in such alternative systems. Therefore, this study aimed to measure blood cortisol (COR) and beta-endorphins (BE) in 22 two-year-old primiparae Fleckvieh cows, who were randomly allotted to the following two different housing systems: CB (n = 11) and FB (n = 11). Blood samples were collected at the beginning of the experiment (T0) and every two months thereafter (T1, T2, and T3). The COR and BE were measured through an immunoenzymatic kit. With the only exception being T0, no differences were observed over time between the two groups, neither for COR nor for BE. However, the blood cortisol levels of the CB cows decreased over time, while a T1 peak was identified in the FB group. On the contrary, both the housing systems displayed numerically higher BE at T3 than at the other experimental times. Therefore, the overall data suggest that the compost-bedded pack barn did not significantly affect the studied parameters. Accordingly, cow welfare should be assessed using a wider panel of animal-based indicators.

Synthetic Olfactory Agonist Use in the Farrowing House to Reduce Sow Distress and Improve Piglet Survival

The aim of the study was to investigate if the application of a synthetic olfactory agonist (SOA) would reduce indicators of stress in sows, in response to a stressor prior to parturition, and if it would improve farrowing house performance of sows and their piglets. Two studies were conducted: an intensive study with 47 sows, either having their first or second litter (Control n = 24; SOA n = 23); and a commercial validation study with 418 sows, either having their first litter or have had multiple litters (Control n = 210; SOA n = 208). Within the intensive study, sows were housed with or without a synthetic olfactory agonist suspended in the creep area of the farrowing crate, whereas within the commercial validation study, sows were housed with or without a synthetic olfactory agonist suspended over the adjoining creep area of two farrowing crates. Within the intensive study, despite a discernible increase in cortisol concentration in response to a stressor (snout rope test), cortisol response was not different between treatments (p > 0.05). Farrowing duration in first-litter sows exposed to the SOA was decreased (p < 0.001) whilst there was no impact on farrowing duration in second litter sows. Piglets were not attracted by the SOA to increase their utilisation of the creep area and spent more time in proximity to the sow (p < 0.05). Within the commercial validation study, no impacts were seen on piglet production measures (p > 0.05). Largely the use of an SOA within the farrowing house did not impact the sow or her piglets in either the intensive study or commercial validation study. Based on these current results, the use of SOA within the farrowing house is not supported.

Perinatal cortisol and blood glucose concentrations in bitches and neonatal puppies: effects of mode of whelping

The decision on how and when to assist whelping is crucial for the survival rate of puppies and health status of the dam. However, medical or surgical therapy in dystocia can impact both maternal and neonatal stress and glucose response differently. This study aims to compare perinatal cortisol and glucose among different modes of delivery in bitches and neonates. We analyzed 50 puppies derived from 27 healthy bitches. According to the condition at birth, bitches and their puppies were allocated into either a Eutocia Group (vaginal birth with no whelping assistance), Fetal Dystocia Group (whelping assistance with fetal manipulation), Maternal Dystocia Group (whelping assistance because of partial uterine inertia corrected by oxytocin administration), or Cesarean Section Group (fetal or maternal dystocia bitches subjected to C-section). Maternal blood cortisol and glucose concentrations were analyzed during the perinatal period (prepartum, intrapartum, postpartum, and 1 h after postpartum). Neonatal blood samples were collected within 5 min and 1 h after birth for assessment of cortisol and glucose. Maternal dystocia bitches had higher cortisol concentrations at postpartum than the Fetal Dystocia Group. At 1 h postpartum, the Cesarean Section Group had higher cortisol concentrations compared with fetal dystocia bitches. The Eutocia Group presented increased cortisol concentrations at intrapartum and postpartum, whereas fetal dystocia bitches had higher intrapartum cortisol concentrations than at 1 h postpartum. The Maternal Dystocia Group presented higher postpartum cortisol concentrations than at prepartum and 1 h postpartum. Maternal glucose had a progressive increase throughout peripartum and was higher during postpartum and at 1 h postpartum. C-section bitches had the highest blood glucose concentration. Neonatal cortisol concentrations at birth were higher than 1 h after birth. Fetal dystocia puppies had higher cortisol concentrations, whereas caesarian section puppies had lower cortisol levels. Fetal dystocia and C-section puppies had higher glucose concentrations than the Eutocia Group. In conclusion, maternal dystocia leads to high cortisol concentrations in bitches immediately postpartum, whereas only fetal dystocia causes increased neonatal cortisol concentrations. Moreover, fetal dystocia and C-section are hyperglycemic obstetrical conditions for neonatal puppies; on the other hand, only C-section causes hyperglycemia in bitches.

The reproductive stress hypothesis

In this paper, we propose the reproductive stress hypothesis that describes the pregnant females response to reproductive events based upon the activation of the hypothalamic–pituitary–adrenal axis and sympathetic adrenomedullary system. The main components of the reproductive stress hypothesis can be summarized as follows: (1) events unique to reproduction including empathema, pregnancy, parturition and lactation cause non-specific responses in females, called active reproductive stress; (2) the fetus is a special stressor for pregnant females where endocrine hormones, including corticotropin-releasing hormones and fetal glucocorticoids secreted by the fetus and placenta, enter the maternal circulatory system, leading to another stress response referred to as passive reproductive stress and (3) response to uterine tension and intrauterine infection is the third type of stress, called fetal intrauterine stress. Appropriate reproductive stress is a crucial prerequisite in normal reproductive processes. By contrast, excessive or inappropriate reproductive stress may result in dysfunctions of the reproductive system, such as compromised immune function, leading to susceptibility to disease. The novel insights of the reproductive stress hypothesis have important implications for deciphering the pathogenesis of certain diseases in pregnant animals, including humans, which in turn may be applied to preventing and treating their occurrence.

Effects of a Dietary L-Carnitine Supplementation on Performance, Energy Metabolism and Recovery from Calving in Dairy Cows

Simple Summary

Dairy cows develop metabolic diseases especially in the transition period due to high energy requirements for the process of calving, beginning milk production and, simultaneously, restricted feed intake capacity. L-carnitine is endogenously synthesised as an obligatory, quaternary amine for the initial step of ß-oxidation, but with the onset of lactation it is also excreted with milk, whereby its availability for other metabolic pathways might be limited. Supplemental L-carnitine might be able to fill in this apparent gap and to enhance the efficiency of ß-oxidation, whereby the magnitude of negative energy balance would be decreased. The present experiment mainly focused on the energy-consuming process of calving itself and on the energy metabolism during the first weeks of lactation.

Abstract

Dairy cows are metabolically challenged during the transition period. Furthermore, the process of parturition represents an energy-consuming process. The degree of negative energy balance and recovery from calving also depends on the efficiency of mitochondrial energy generation. At this point, L-carnitine plays an important role for the transfer of fatty acids to the site of their mitochondrial utilisation. A control (n = 30) and an L-carnitine group (n = 29, 25 g rumen-protected L-carnitine per cow and day) were created and blood samples were taken from day 42 ante partum (ap) until day 110 post-partum (pp) to clarify the impact of L-carnitine supplementation on dairy cows, especially during the transition period and early puerperium. Blood and clinical parameters were recorded in high resolution from 0.5 h to 72 h pp. L-carnitine-supplemented cows had higher amounts of milk fat in early lactation and higher triacylglyceride concentrations in plasma ap, indicating increased efficiency of fat oxidation. However, neither recovery from calving nor energy balance and lipomobilisation were influenced by L-carnitine.

Influence of dog-appeasing pheromone on canine maternal behaviour during the peripartum and neonatal periods

Background

Parturition and the initial postpartum period are important moments in the reproductive cycle of dogs.

Methods

A study assessed the effect of ADAPTIL, a dog-appeasing pheromone, on maternal behaviour during peripartum. Bitches were continuously exposed to ADAPTIL (n=20) or placebo (n=21) in double-blinded conditions from an average of about seven days before parturition up to 21 days postpartum. Differences in maternal behaviour in relation to the treatment were evaluated by the observation of specific activities through video recordings, such as the time spent by the bitch in close contact with the puppies, oronasal interaction and nursing duration and position. Videos were recorded at four time points (W0: within the first 48 hours of whelping; W1: one week after parturition; W2: two weeks after parturition; and W3: three weeks after parturition). In addition, the perception of breeders in relation to the quality of maternal care, puppies’ wellbeing and overall relationship between the bitches and the puppies was evaluated using Visual Analogue Scale at the same time points. Moreover, the daily activity of the bitches was measured by using an electronic device (FitBark dog activity trackers, Kansas City, Missouri).

Results

For all observed maternal behaviours, there was a steady decrease in levels as the puppies developed, independently of treatment. However, bitches exposed to ADAPTIL tended to nurse significantly more in lying position, while those exposed to the placebo nursed more in a seated position, especially at W1 (P=0.06) and W3 (P=0.005). According to the breeders, the attention scores of bitches towards puppies were significantly higher in ADAPTIL than in the placebo group at each time point (P=0.01). Moreover, a difference according to parity was observed (P=0.004), with greater attention score displayed by primiparous bitches exposed to ADAPTIL compared with placebo on W0 (P=0.02), W1 and W3 (P<0.001). The global mother–puppies relationship was also perceived as significantly better (P=0.0002) by breeders of bitches exposed to ADAPTIL, with significant differences at W2 (P=0.01) and W3 (P=0.001). The bitches’ daily activity increased starting two days before the whelp, peaked during parturition and then gradually declined up until four days postpartum. There was a trend towards a difference in the activity level according to the treatment during the full study period (P=0.09) and at two days before parturition (P=0.07). Bitches exposed to ADAPTIL were more active compared with placebo in relation to the FitBark data.

Conclusion

The use of ADAPTIL in maternity modulated maternal behaviours. Concerning the caregiver’s view, bitches under the influence of ADAPTIL had greater and extended attention towards the puppies and they were eager to stay with the puppies for a longer time.

Stress effects on the regulation of parturition in different domestic animal species

This review summarizes current knowledge on stress-like responses in parturient animals and their role for the onset and fine-tuning of parturition. The antepartum maternal cortisol increase is part of the endocrine changes that initiate parturition but a further increase in cortisol release during labor indicates a stress response. During the last minutes of delivery, sinus arrhythmias occur in 80% of foaling mares and 60% of calving cows. Expulsion of the neonate is thus characterized by parasympathetic dominance. In late-pregnant cows transported by road, cortisol concentrations increased but relations between transport stress and abortion remain unclear. In mares, transport not only elicited a stress response but also advanced the time of foaling. Transferring parturient rats, mice and pigs after birth of the first pup or piglet, respectively, to a stressful environment prolonged the time until delivery of the next littermate. In rats and pigs, this was caused by an increased opioidergic tone that restrained oxytocin release. In mice, a stress-induced delay of subsequent deliveries was caused by increased sympathoadrenal activity. When foaling mares were transferred to an uncomfortable stable at fetal membrane rupture, time until complete birth of the foal was doubled. As in mice, increased sympathetic activity was the mechanism delaying the progress of foaling. An increased sympathetic activity is also present in parturient cows disturbed during an early stage of calving. In equine and bovine neonates, the immediate postnatal period is characterised by high sympathetic activity and an increase in cortisol concentration, indicating a pronounced stress-like response.

Influence of denaverine hydrochloride on calving ease in Holstein-Friesian heifers

Calving is assumed to be an exhausting and painful event. A drug that eases the calving procedure and alleviates pain would help cows, especially those suffering from dystocia. In a randomized, controlled, and blinded trial, we measured the effect of denaverine hydrochloride on physical and physiological calving parameters. Eighty-three Holstein-Friesian heifers were included in the analysis. Pulling force was measured using a digital force gauge interposed between the calf and a mechanical calf puller. The concentration of cortisol was measured in serum before and after parturition. There was no effect of treatment group on calving modality (i.e., spontaneous vs. assisted calving), duration of calving, and cortisol concentration. The area under the curve of pulling force × time (n = 44), however, was significantly smaller in the treatment group compared with the placebo group. Also, duration of calving assistance was numerically shorter in the treatment group compared with the placebo group. The results provide evidence that calving ease can be influenced by denaverine hydrochloride during calving assistance.

Detection of quantitative trait loci for maternal traits using high-density genotypes of Blonde d'Aquitaine beef cattle

Background

The genetic determinism of the calving and suckling performance of beef cows is little known whereas these maternal traits are of major economic importance in beef cattle production systems. This paper aims to identify QTL regions and candidate genes that affect maternal performance traits in the Blonde d’Aquitaine breed. Three calving performance traits were studied: the maternal effect on calving score from field data, the calving score and pelvic opening recorded in station for primiparous cows. Three other traits related to suckling performance were also analysed: the maternal effect on weaning weight from field data, milk yield and the udder swelling score recorded in station for primiparous cows. A total of 2,505 animals were genotyped from various chip densities and imputed in high density chips for 706,791 SNP. The number of genotyped animals with phenotypes ranged from 1,151 to 2,284, depending on the trait considered.

Results

QTL detections were performed using a Bayes C approach. Evidence for a QTL was based on Bayes Factor values. Putative candidate genes were proposed for the QTL with major evidence for one of the six traits and for the QTL shared by at least two of the three traits underlying either calving or suckling performance. Nine candidate genes were proposed for calving performance among the nine highlighted QTL regions. The neuroregulin gene on chromosome 27 was notably identified as a very likely candidate gene for maternal calving performance. As for suckling abilities, seven candidate genes were identified among the 15 highlighted QTL. In particular, the Group-Specific Component gene on chromosome 6, which encodes vitamin D binding protein, is likely to have a major effect on maternal weaning weight in the Blonde d’Aquitaine breed. This gene had already been linked to milk production and clinical mastitis in dairy cattle.

Conclusion

In the near future, these QTL findings and the preliminary proposals of candidate genes which act on the maternal performance of beef cows should help to identify putative causal mutations based on sequence data from different cattle breeds.

Electronic supplementary material

The online version of this article (doi:10.1186/s12863-016-0397-y) contains supplementary material, which is available to authorized users.

Effect of dystocia on some hormonal and biochemical parameters in the one-humped camel (Camelus dromedarius)

The present study compared some of the hormonal and biochemical constituents of serum from eutocic and dystocic one-humped camels (Camelus dromedarius). Sera were harvested from eutocic (n = 9) and dystocic (n = 20) camels within the first 15 minutes after delivery. Although there were no differences in the concentrations of estradiol-17β (E2) and prostaglandin F2α (PGF2α) between the eutocic and the dystocic animals, the level of progesterone (P4) and cortisol was significantly higher (P < 0.01) in animals that experienced dystocia than those that had a normal birth. There were no differences between the concentrations of alkaline phosphatase, aspartate aminotransferase, calcium, cholesterol, creatine kinase, creatinine, or magnesium (Mg) in eutocic and dystocic animals. The nitric oxide concentration was significantly higher (P < 0.01) in the serum from animals with dystocia than those that had normal births. By contrast, the serum concentrations of glucose, phosphorus (P), and triglycerides were significantly lower (P < 0.01) in eutocic camels compared with dystocic camels. As the delayed decline of P4 is reported to be the major hormonal difference between eutocic and dystocic camels, we propose that the insensitivity of corpus luteum to luteolytic action may be a cause of dystocia. Moreover, stress and hormonal changes may affect the metabolic traits in dystocia camels.

Experimental study on the effect of oral meloxicam administration in sows on pre-weaning mortality and growth and immunoglobulin G transfer to piglets

Parturation is an intrinsically risky and painful process for both the sow and the piglets that can cause welfare and economic problems. Non-steroidal anti-inflammatory drugs (NSAIDs) have been demonstrated to partially alleviate inflammation and pain after farrowing in sows. NSAIDs effects on piglet mortality and performance show discrepancies and no previous studies have investigated the underlying mechanism. The effects of oral meloxicam treatment to sows on immunoglobulin G (IgG) transfer to piglets around farrowing were investigated. A total of 30 multiparous sows were randomly treated with either oral meloxicam or a mock administration as control group. Treatment was administered as soon as possible at the beginning of the farrowing. A total of 325 piglets were individually weighed at farrowing (day 0) and at weaning (day +21) and piglet mortality was registered during lactation. Four piglets per sow (two piglets suckling from anterior teats and two piglets suckling from posterior teats) were selected for blood sampling at day +1, day +2 and day +20 for IgG analyses. Oral meloxicam treatment to sows significantly increased weight at weaning (mean±SE: 6563±86.3g from oral meloxicam group and 6145±103.2g from control group; P=0.0017) and ADG (mean±SE: 236±3.4g/day from oral meloxicam group and 217±4.5g/day from control group; P<0.001) during lactation, but failed to reduce piglet mortality during lactation (6.7% from oral meloxicam group and 6.8% from control group; P=0.89). IgG levels in piglets from the sows treated with oral meloxicam were significantly higher than the control group at day +1 (mean; median [95% CI] for median=31.9; 31.7 [29.6-33.6] vs. 27.9; 26.8 [25.9-28.3] mg/ml, P=0.0013) and day +2 (27.6; 27.0 [24.8-29.6] vs. 24.5; 24.2 [22.1-25.3] mg/ml, P=0.01). However, at day +20, IgG level in piglet serum was not significantly affected by the treatment (7.6; 7.6 [6.7-8.4] vs. 7.1; 6.9 [6.4-7.3] mg/ml, P=0.59). The administration of meloxicam orally at the beginning of the farrowing in multiparous sows increased the concentration of IgG in serum of piglets and enhanced their pre-weaning growth. Future research is warranted to clearly identify the proximate mechanism behind IgG effect.

Sympathoadrenal balance and physiological stress response in cattle at spontaneous and PGF2α-induced calving

Increased cortisol release in parturient cows may either represent a stress response or is part of the endocrine changes that initiate calving. Acute stress elicits an increase in heart rate and decrease in heart rate variability (HRV). Therefore, we analyzed cortisol concentration, heart rate and HRV variables standard deviation of beat-to-beat interval (SDRR) and root mean square of successive beat-to-beat intervals (RMSSD) in dairy cows allowed to calve spontaneously (SPON, n = 6) or with PGF2α-induced preterm parturition (PG, n = 6). We hypothesized that calving is a stressor, but induced parturition is less stressful than term calving. Saliva collection for cortisol analysis and electrocardiogram recordings for heart rate and HRV analysis were performed from 32 hours before to 18.3 ± 0.7 hours after delivery. Cortisol concentration increased in SPON and PG cows, peaked 15 minutes after delivery (P < 0.001) but was higher in SPON versus PG cows (P < 0.001) during and within 2 hours after calving. Heart rate peaked during the expulsive phase of labor and was higher in SPON than in PG cows (time × group P < 0.01). The standard deviation of beat-to-beat interval and RMSSD peaked at the end of the expulsive phase of labor (P < 0.001), indicating high vagal activity. Standard deviation of beat-to-beat interval (P < 0.01) and RMSSD (P < 0.05) were higher in SPON versus PG cows. Based on physiological stress parameters, calving is perceived as stressful but expulsion of the calf is associated with a transiently increased vagal tone which may enhance uterine contractility.

Validation of a field technique and characterization of fecal glucocorticoid metabolite analysis in wild chimpanzees (Pan troglodytes)

Monitoring adrenocortical activity in wild primate populations is critical, given the well-documented relationship between stress, health, and reproduction. Although many primate studies have quantified fecal glucocorticoid metabolite (FGM) concentrations, it is imperative that researchers validate their method for each species. Here, we describe and validate a technique for field extraction and storage of FGMs in wild chimpanzees (Pan troglodytes). Our method circumvents many of the logistical challenges associated with field studies while yielding similar results to a commonly used laboratory method. We further validate that our method accurately reflects stress physiology using an adrenocorticotropic hormone challenge in a captive chimpanzee and an FGM peak at parturition in a wild subject. Finally, we quantify circadian patterns for FGMs for the first time in this species. Understanding these patterns may allow researchers to directly link specific events with the stress response.

Effect of a difficult calving on the vigour of the calf, the onset of maternal behaviour, and some behavioural indicators of pain in the dam

The neonate's development and survival is dependent upon being vigorous at birth and receiving appropriate maternal care. However, difficulty at delivery can result in less vigorous offspring and maternal care can be altered, probably as a consequence of exhaustion, pain and human intervention. The first 3h after expulsion of the calf were observed continuously from videos following twelve natural calvings and sixteen calvings assisted by farm staff (including four malpresentations) from Holstein cows. Calvings were balanced within groups for parity of the dam, genetic group, sex and birth weight of the calf, calving pen and calving season. Assisted calves were less vigorous with higher latencies to attempt to stand, achieve standing, walk and reach the udder than unassisted calves (P<0.05). Furthermore, assisted calves also tended to be less likely to stand and walk within the first 3h after birth (P<0.1), spent more time lying on their flank (P=0.019) and had more frequent bouts of this behaviour (P=0.033). Assisted dams did not take longer to lick the calf and performed as much licking as unassisted dams (P>0.05), indicating no delayed onset or impaired expression of maternal behaviour in dams given assistance at delivery. Study of potential pain-related behaviours revealed that assisted dams spent less time self-grooming (P=0.033) than dams delivering naturally, which could suggest greater pain. However, there were no significant differences in any of the other pain-related behaviours. Our results suggest that, although maternal behaviour was unaffected by a difficult delivery, dairy calves born following difficult calvings have lower vigour in the first 3h after birth than unassisted calves. This might have longer-term effects on the health and survival of the calves.

Cardiovascular, endocrine and behavioural responses to suckling and permanent separation in goats

Background

Suckling can be a peaceful or vulnerable event for goats and kids, whereas, separation is suggested as stressful. The aim of this study was to investigate physiology and behaviour in these two different situations in dairy goats.

Methods

Four studies were performed with seven goats kept with their first-born kid in individual boxes. The goats were videotaped and heart rate and arterial blood pressure were recorded every minute by telemetry from parturition until 24 hours after separation. One to two days after parturition, Study 1 was performed with analyses of heart rate and blood pressure around a suckling. In Study 2, performed 3-5 days after parturition, blood sampling was done before, during and after suckling. Study 3 was performed 4-6 days post partum, with blood sampling before and after a permanent goat and kid separation. In addition, vocalisations were recorded after separation. Blood samples were obtained from a jugular vein catheter and analysed for plasma cortisol, β-endorphin, oxytocin, and vasopressin concentrations. Study 4 was performed during the first (N1) and second nights (N2) after parturition and the nights after Study 2 (N3) and 3 (N4). Heart rate, blood pressure and time spent lying down were recorded.

Results

The kids suckled 2 ± 0.2 times per hour and each suckling bout lasted 43 ± 15 s. In Study 1, heart rate and blood pressure did not change significantly during undisturbed suckling. In Study 2, plasma cortisol (P ≤ 0.05 during suckling and P ≤ 0.01 five minutes after suckling) and β-endorphin (P ≤ 0.05) concentrations increased during suckling, but oxytocin and vasopressin concentrations did not change. In Study 3, the goats and kids vocalised intensively during the first 20 minutes after separation, but the physiological variables were not affected. In Study 4, heart rate and arterial blood pressure declined gradually after parturition and were lowest during N4 (P ≤ 0.05) when the goats spent longer time lying down than during earlier nights (P ≤ 0.01 during N1 and N3 and P ≤ 0.05 during N2).

Conclusions

Suckling elevated plasma cortisol and β-endorphin concentrations in the goats. The intensive vocalisation in the goats after separation, earlier suggested to indicate stress, was not accompanied by cardiovascular or endocrine responses.

Oxytocin, vasopressin, prostaglandin F(2alpha), luteinizing hormone, testosterone, estrone sulfate, and cortisol plasma concentrations after sexual stimulation in stallions

This experiment was designed to determine the effects of sexual stimulation on plasma concentrations of oxytocin (OT), vasopressin (VP), 15-ketodihydro-PGF(2alpha) (PG-metabolite), luteinizing hormone (LH), testosterone (T), estrone sulfate (ES), and cortisol (C) in stallions. Semen samples were collected from 14 light horse stallions (Equus caballus) of proven fertility using a Missouri model artificial vagina. Blood samples were collected at 15, 12, 9, 6, and 3 min before estrous mare exposure, at erection, at ejaculation, and at 3, 6, and 9 min after ejaculation. Afterwards, blood sampling was performed every 10 min for the following 60 min. Sexual activity determined an increase in plasma concentrations of OT, VP, C, PG-metabolite, and ES and caused no changes in LH and T concentrations. The finding of a negative correlation between C and VP at erection, and between C and T before erection and at the time of erection, could be explained by a possible inhibitory role exerted by C in the mechanism of sexual arousal described for men.

Effect of neonatal nociceptin or nocistatin imprinting on the brain concentration of biogenic amines and their metabolites

Noradrenaline (NA), dopamine (DA), homovanillic acid (HA), serotonin (5HT) and 5-hydroxyindole acetic acid (5HIAA) content of five brain regions (hypothalamus, hippocampus, brainstem, striatum and frontal cortex) and the cerebrospinal fluid (CSF) was measured in adult (three months old) male and female rats treated neonatally with a single dose of 10 microg nociceptin (NC) or 10 microg nocistatin (NS) for hormonal imprinting. The biogenic amine and metabolite content of cerebrospinal fluid was also determined. In NC treated animals the serotonergic, dopaminergic as well as noradrenergic systems were influenced by the imprinting. The 5HT level increased in hypothalamus, the 5HIAA tissue levels were found increased in hypothalamus. Hippocampus and striatum and the HVA levels increased highly significantly in brainstem. Dopamine level decreased significantly in striatum, however in frontal cortex both noradrenalin and 5HIAA level decreased. Nevertheless, in NS-treated rats decreased NA tissue levels were found in hypothalamus, brainstem and frontal cortex. Decreased DA levels were found in the hypothalamus, brainstem and striatum. NS imprinting resulted in decreased HVA level, but increased one in the brainstem. The 5HT levels decreased in the hypothalamus, brainstem, striatum and frontal cortex, while 5HIAA content of CSF, and frontal cortex decreased, and that of hypothalamus, hippocampus and striatum increased. There was no significant difference between genders except in the 5HT tissue levels of NC treated rats. Data presented show that neonatal imprinting both by NC and NS have long-lasting and brain area specific effects. In earlier experiments endorphin imprinting also influenced the serotonergic system suggesting that during labour release of pain-related substances may durably affect the serotonergic (dopaminergic, adrenergic) system which can impress the animals' later behavior.

Plasma vasopressin and oxytocin concentrations increase simultaneously during suckling in goats

Goats are often kept on small farms where they suckle kids and are hand milked for human consumption. Our first objective was to investigate whether vasopressin secretion increases together with oxytocin during hand milking and suckling in seven goats 6-8 weeks after parturition. Four goats suckled and three were hand milked on the first day and the treatments were reversed on the next day. Blood samples were taken via a semi-permanent catheter. Plasma concentrations of vasopressin and oxytocin increased during suckling, but not during hand milking. Plasma cortisol concentration was elevated for 10 min after both treatments. These results initiated a second series in which the objectives were to measure vasopressin and oxytocin concentrations during hand milking in a larger number of goats and to investigate whether the rise in cortisol concentration was due to the experimental conditions or to milking, by adding a no-milking treatment. Nine goats in lactation weeks 4-10 were studied. Heart rate and arterial blood pressure were registered in eight of the goats. Oxytocin concentration did not change during hand milking and the vasopressin concentration was below the detection limit. Heart rate and blood pressure were elevated during milking and for about 10 min thereafter. Cortisol concentration increased after milking, as above. None of the variables changed in the no-milking treatment. This suggests that the rise in cortisol concentration was due to milk excretion and was not a stress reaction. In conclusion, suckling increased plasma concentrations of vasopressin and oxytocin, but hand milking did not. In a mixed system, presence of the kids may be necessary to stimulate release of the peptides and thereby contraction of the myoepithelial cells. However, milk stored in the udder cisterns can be obtained by hand milking without presence of oxytocin or vasopressin.

The relation between the birth process and the condition of the newborn piglet and calf

This presentation will focus on the assessment of the condition of the piglet and calf during and shortly after birth and will review some of the physiological and clinical factors that may have played a role during their delivery and influenced their viability at birth.

Clinical pharmacology of buprenorphine in healthy, lactating goats

The pharmacokinetics and the effects of the opioid buprenorphine on behavior, cardiovascular parameters, plasma concentrations of cortisol and vasopressin were studied in the goat. After intravenous injection at a dosage of 0.02 mg/kg bw, the terminal half-life was 73.8+/-19.9 min (mean+/-SD), the apparent volume of distribution 5.22+/-1.01 L/kg, and total body clearance 79.1+/-18.5 mL/min/kg. After intramuscular administration of buprenorphine at the same dosage, bioavailability was complete and clearance was 54.7+/-16.6 mL/min/kg. Heart rate, blood pressure and concentrations of cortisol and vasopressin in plasma increased after drug administration. The goats became agitated and stopped ruminating. The effects were more pronounced the first time the animals received the drug, especially the influence on the hormone levels. The concentrations of cortisol and vasopressin in plasma remained unaffected after the second dose despite a wash-out period of 3-6 weeks. Buprenorphine may be an unsuitable drug in goats because of the profound inhibition of rumination and the agitation it causes. The short half-life of buprenorphine may limit its use if long-term analgesia is required but be advantageous if a short acting drug is desirable.

Dexamethasone depresses the expression of l-selectin but not the in vivo migration of bovine neutrophils into the uterus

There are several indications that periparturient depression of functional properties of polymorphonuclear neutrophilic granulocytes (PMN) may be of great importance for the pathogenesis of genital infections after calving. As the periparturient period is characterized by high plasma levels of corticosteroids, the hypothesis to be tested was that high concentrations of glucocorticoids during the periparturient period suppress uterine PMN in number and functionality. An in vivo endometritis model was applied to examine uterine PMN. Recombinant human interleukin-8 (rhIL-8) was infused into the uterus of estrous cows and heifers 24 h after pretreatment with dexamethasone (0.07 mg/kg i.m.). Six hours after rhIL-8 infusion high numbers of uterine PMN were isolated and characterized as to their immunophenotype and function. Animals treated with dexamethasone animals showed leucocytosis due to neutrophilia in peripheral blood. Despite a downregulation of expressed L-selectin, cattle treated with dexamethasone showed more uterine PMN than those treated with placebo. Dexamethasone decreased plasma concentrations of the immunomodulatory steroidal hormones cortisol and estrogen. Dexamethasone directly reduced the generation of reactive oxygen species (ROS) by uterine PMN. This may be a useful mechanism since it would protect the endometrium from tissue damage by excessive extracellular ROS. However, it is not known if the net effect is in fact a reduction in ROS, as the number of uterine cells increases. Our study shows that glucocorticoids may not be considered immunosuppressive in all cases and may play an important role in the regulation of post partum uterine defense mechanisms.

Comparison of T Cell Subsets Between Somatic Cloned and Normal Cow

PROBLEM

Somatic cloning technology is beneficial for genetically producing excellent animals. However, many developmental problems of somatically cloned animals have been described. Some of them may cause disorders of the immune system, resulting in the fluctuation of the proportion of white blood cells (WBC), different from that of normal animals in peripheral blood.

METHOD OF STUDY

In Holstein- cloned and normal cows, the fluctuation of granulocytes, monocytes, B cells and T cells, and further T cell subsets (CD4+, CD8+, gammadelta, CD8+gammadelta and WC1+gammadelta T cell) in peripheral blood were analyzed in early lactation stage (ELS) and mid to late lactation stage (MLS) by flow cytometry using specific monoclonal antibodies for cell surface markers.

RESULTS

In both ELS and MLS, there were no significant differences in the proportions of granulocytes, monocytes, B cells and T cells between cloned and normal cows. In T cell subsets, gammadelta and WC1+gammadelta T cells in cloned cows were significantly less frequent than in normal cows in ELS. The decreased proportions of gammadelta and WC1+gammadelta T cells recovered to the level of normal cows in MLS.

CONCLUSIONS

The population of granulocytes, monocytes, B cells and T cells, and T cell subsets except for gammadelta and WC1+gammadelta T cells in cloned cows fluctuated in a manner similar to those of normal cows during lactation. In ELS, the proportions of gammadelta and WC1+gammadelta T cells temporarily declined in cloned cows, suggesting that cloned cows may fall into an immunosuppressive state in ELS.

The cow in endocrine focus before and after calving

During the period 1 month before and 1 month after parturition in the cow, several events take place. The dam has to be prepared for the impending parturition and the uterus and ovaries must return to a certain stage to be prepared for a new pregnancy. Most of these processes are due to or reflected in endocrine changes. A special interest is of course the status of the foetus --"foetal well being". The processes could either be considered as normal in a clinical perspective or as impaired (dystocia, small calves, stillbirth, retained foetal membranes, etc.). The main question for this presentation is if normal and impaired performance could be mirrored in endocrine parameters. Many studies have been performed to follow endocrine changes during the periparturient period in the cow. The following parameters have been shown to be the most important and seem to be the most suitable for an endocrine supervision: Endocrine parameter: progesterone; parameter of: corpus luteum, maternal adrenals, placenta. Endocrine parameter: prostaglandin (PG) metabolite; parameter of: placenta, uterus, inflammation. Endocrine parameter: cortisol; parameter of: regulator of prostaglandin synthesis, stress. Endocrine parameter: free oestrogens; parameter of: placenta, ovaries. Endocrine parameter: oestrone sulphate; parameter of: placenta, calf weight. Endocrine parameter: pregnancy-associated glycoproteins (PAG); parameter of: placenta.

Increased plasma concentrations of vasopressin, oxytocin, cortisol and the prostaglandin F2alpha metabolite during labour in the dog

AIM

This study investigated if the plasma vasopressin concentration increases during labour in the dog and whether the change in vasopressin correlates with that of oxytocin, 15-ketodihydro-PGF2alpha and cortisol.

METHODS

Five beagle dogs each delivered three to seven puppies. Blood samples were taken from a catheter inserted into the cephalic vein during labour and by venepuncture during the other periods.

RESULTS

Vasopressin concentration increased from 2 +/- 0 pmol L-1 (anoestrus) to 26 +/- 11 pmol L-1 at the birth of the first puppy, remained high at the birth of the second puppy and then decreased. Oxytocin increased from 63 +/- 5 pmol L-1 (anoestrus) to 166 +/- 19 pmol L-1 at the birth of the first puppy and remained elevated throughout labour. The PGF2alpha metabolite concentration increased from 0.2 +/- 0.0 nmol L-1 (anoestrus) to 66 +/- 17 nmol L-1 at the birth of the first puppy and remained elevated 1 h after the completion of parturition. The cortisol concentration increased from 49 +/- 9 nmol L-1 (anoestrus) to 242 +/- 35 nmol L-1 at the birth of the first puppy, remained high during the birth of the second puppy and then declined.

CONCLUSIONS

The plasma level of vasopressin was strongly correlated with that of cortisol but less with that of the PGF2alpha metabolite, and not significantly with the concentration of oxytocin. This indicates that the four hormones play different roles during labour in the dog.

Periparturient endocrine and metabolic changes in healthy cows and in cows affected by mastitis

Transition from pregnancy to lactation in dairy cows involves considerable metabolic adaptation. Additional stress is incurred during infections such as periparturient mastitis. Multiparous Holstein-Friesian cows kept under normal production conditions (n = 15) were used to evaluate changes in circulating metabolite and hormone concentrations from 5 days before to 5 days after calving. Insulin-like growth factor binding protein (IGFBP) profiles were also monitored. Marked time-related changes were observed for plasma thyroid hormone, IGF, cortisol, insulin, beta-hydroxybutyrate (BHB) and non-esterified fatty acid (NEFA) concentrations but not for plasma leptin. A decrease in IGF-II concentration and maximal intensity of the putative IGFBP-1 band occurred at parturition. When compared with the five healthy cows,low IGF-II levels were prolonged to day 2 post-partum in five cows with Escherichia coli-associated mastitis. However, marked decreases in IGFBP-2 band intensity were evident only in two of the four cases examined. Individual total ligand (IGF-I + IGF-II) concentration and IGFBP pattern prepartum were largely regained 5 days post-partum in all cows. Hormone and metabolite concentrations in the two cows with Staphylococcus aureus-associated mastitis were very similar to those in the five healthy cows. Plasma thyroxine (T4) was lower 2 days prepartum in the cows, which later developed Gram-negative mastitis. Multiregression analysis showed that variance in T4 concentration was significantly and independently associated with triiodothyronine (T3) and IGF-I positively and with cortisol negatively (R2 = 0.648). This study confirms the close inter-relationship between the thyroid hormone and IGF axes in cattle and indicates possible effects of Gram-negative mastitis infection on IGF-II metabolism.