[Diurnal rhythms and time fluctuation--an animal welfare problem?].
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Animal Husbandry↗
Biomedical subjects
J Ladewig
Publications and source records attributed to J Ladewig.
Behavior, episodic secretion of cortisol, and adrenocortical reactivity in bulls subjected to tethering.
To study the effect of individual housing on behavior and adrenocortical activity, eight bulls were moved to a novel housing environment and subjected to 5 weeks of tethering in individual stanchions with a concrete and partially slatted floor. During the first and fourth week, resting behavior and episodic cortisol secretion were analyzed over two 24-hr periods and compared to those of eight control bulls kept free on deep straw. In addition, in the fifth week adrenocortical reactivity after ACTH(1-24) stimulation was analyzed in all subjects. Resting behavior was markedly influenced by type of housing. Although duration of lying down over 24 hr was similar in tethered and control bulls, the number of periods of lying down was significantly reduced and the frequency of investigating the lying area prior to lying down was significantly increased in tethered bulls. In the first week of study, the cortisol secretory patterns of experimental and control bulls differed. The frequency of secretory episodes was significantly reduced, and the mean amplitude of the episodes increased, though not significantly in experimental compared with control bulls. After 4 weeks of tethering, however, the secretory pattern had returned to levels similar to those of control bulls. Despite this return of the basic cortisol secretion, adrenocortical reactivity after a high dosage of ACTH(1-24) was significantly reduced in tethered bulls. The results suggest that an adaptation to tethering at the brain-pituitary level does not occur, but that the return of the basal cortisol secretion could be due to changes at the adrenocortical level.
Adrenal Cortex↗
Behavior and heart rate of heifers housed in tether stanchions without straw.
The effect of tether housing without straw was studied in eight heifers over a 12-week period. Resting behavior was recorded in the first and the twelfth week and heart rate (HR) in the twelfth week and compared to that of eight control heifers kept in a group on deep straw. Tethered heifers changed body position from standing to lying and vice versa significantly less often, and frequency of lying intention movements prior to lying down was significantly increased in tethered heifers. Correspondingly, latency between first intention movement and actually lying down was markedly increased in tethered heifers. HR was significantly higher in tethered heifers in all situations studied. During the lying procedure, HR increased in all animals so that the difference between the two groups remained unchanged. The biggest difference between groups was measured during the first lying intention, when HR was 125.2 +/- 9.4 in tethered heifers and 76.8 +/- 6.1 in controls. The results indicate that lying down in tether stanchions is aversive to the heifers and avoided as much as possible.
Animals↗
Altered adrenocortical response to acute stressors or ACTH(1-24) in intensively housed pigs.
In two experiments, the effect of intensive housing on behavior and adrenocortical reactivity was studied in 68 castrated male German Landrace pigs. In both experiments, half of the pigs were tethered on a partially slatted floor without straw and half were kept, as controls, in groups on straw. Prior to the study, 32 of the pigs used in the first experiment were selected according to their reaction to halothane anesthesia; for the second experiment, 36 pigs were selected according to their adrenocortical response to azaperone-metomidate anesthesia. During the 4- to 6-wk experimental period, behavioral activity was observed and adrenocortical reactivity was analyzed after stimulation with synthetic ACTH(1-24), azaperone-metomidate anesthesia, insulin-induced hypoglycemia and neostigmine-atropine. Although no difference was found in general activity between groups, tethered pigs revealed a significantly higher cortisol increase after stimulation with ACTH(1-24) in both experiments and after insulin stimulation in the second experiment. Similarly, the area below the cortisol response curve after ACTH stimulation was significantly larger in tethered pigs in the second experiment. The individual reaction pattern was positively correlated between tests, indicating this pattern is a relatively constant, individual characteristic. In contrast, no correlation was found between behavior or adrenocortical reaction pattern and sensitivity to halothane. The results suggest that tethering on a partially slatted floor constitutes a chronic stressor which changes the adrenocortical response to an additional acute stressor. This increased reactivity is revealed most clearly after stimulation with ACTH(1-24) when individual responsiveness is taken into consideration.
Adrenal Cortex↗
[Stress, health and production in swine].
The "porcine stress syndrome" is a well established concept. Effects exerted on part of the meat type pig populations by their increased susceptibility to stress, resulting in meat quality defects, are meant by it. The problem of stress is rather a complex phenomenon. Stress is a part of daily life and can have negative as well as positive effects on performance and health, depending on its intensity and duration. These connections are discussed in the following paragraphs: 1. Definition of stress, and of stress-related reactions and possibilities of their assessment. 2. Stressors and their effects on the performance and health of pigs with regard to genetic dispositions. 3. Conclusions for the avoidance of stress effects in pig production.
Animals↗
A simplified method for stress free continuous blood collection in large animals.
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Animals↗
A case of "reversed cannibalism": the piglets damaging the sow.
Sows introduced to a new housing system containing farrowing pens with slatted floor showed increased occurrence of lesions of the vulvar region, caused by the piglets during the later stages of the lactation period. An investigation was undertaken in which the activity of the piglets, particularly rooting and investigatory behavior, was examined and compared to that of piglets kept on straw. Although the occurrence of vulvar lesions disappeared spontaneously before the conduction of the investigation, the results revealed that piglets on slatted floor spent significantly more time chewing on inappropriate objects such as other group members or the vulva of the sow, whereas the rooting and investigatory behavior of piglets raised on straw was almost exclusively directed towards the straw. The results confirm previous observations that piglets living in a relatively poor environment show a greater tendency to direct their activity towards inappropriate objects. If the housing system is otherwise healthy, the change in behavioral activity remains insignificant. If, however, other minor disturbances occur in the system, in the present case clinically insignificant lesions on the vulva of the sow caused by the new slatted floor, aggravation of the lesions can occur due to this change in piglet activity.
Age Factors↗
An electrophysiological study of the accessory olfactory bulb in the rabbit--II. Input-output relations as assessed from analysis of intra- and extracellular unit recordings.
The input-output relations of the rabbit accessory olfactory bulb were studied by intra- and extracellular single unit recordings following electrical stimulation of the vomeronasal nerves, the lateral olfactory tract and the corticomedial amygdala. Cellular activity of accessory bulb mitral cells evoked by stimulation of the vomeronasal nerves consisted of a brief excitation with a latency of 16 ms. This initial response was followed by a period of reduced firing probability which was due to an inhibitory postsynaptic potential. In many cases this secondary response was followed by a second excitatory postsynaptic potential on which action potentials were generated at higher stimulus intensities. Deeper cells in the granule cell layer responded with a long latency, long duration, excitation, often consisting of bursts of 2-3 spikes. The majority of mitral cells were antidromically invaded by amygdala stimulation. The latencies of the antidromic spikes showed a wide range of variation (12-80 ms). Due to this great variation in antidromic latency the inhibitory postsynaptic potential following the antidromic action potential was rather modest but prolonged in duration. In many cases the onset of the inhibitory postsynaptic potential preceded the antidromic response. The majority of cells did not respond to lateral olfactory tract stimulation. Only 10% of the tested cells were invaded antidromically by stimulation at this site. These neurons were also driven antidromically by amygdala stimulation. We conclude that, although the physiological characteristics of mitral cells of the main and accessory olfactory bulb are very similar, there are important differences. The efferent fibres of the accessory bulb conduct at very slow and variable rates and project directly to the corticomedial amygdala.
Amygdala↗
Demonstration of estrus-related odors in cow urine by operant conditioning of rats.
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Animals↗
Flehmen and vomeronasal organ function in male goats.
The possible role of flehmen behavior in facilitating the passage of non-volatile materials from the oral cavity to the vomeronasal organ (VNO) was studied by the use of a tracer dye, sodium fluorescein. The dye was applied to the oral cavity of six male goats in which flehmen was elicited by the presentation of female urine. Immediately afterwards a lethal dosage of anesthetic was given and the maxilla, including the VNO, was removed, frozen, and cut into transverse sections. Seven control subjects were treated similarly but were not stimulated to display flehmen. Examination of transverse sections under ultraviolet illumination revealed dye in the posterior part of the VNO in most subjects that performed flehmen but only in the anterior part of the VNO of subjects that did not perform flehmen. Inasmuch as only the middle and posterior parts of the VNO contain sensory epithelium, it was concluded that, if the dye represented a behaviorally significant non-volatile material (sex attractant), only the goats that showed flehmen would have detected the material from VNO chemoreception.
Animals↗
Flehmen in male goats: role in sexual behavior.
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Animals↗
Accelerated and enhanced testosterone secretion in juvenile male dogs following medial preoptic-anterior hypothalamic lesions.
Lesions of the medial preoptic-anterior hypothalamic (MP-AH) continuum made in juvenile male dogs (10-11 weeks of age) were previously reported to reduce juvenile mounting and virtually eliminate male copulatory behavior in adulthood. The effects of these lesions on the developmental patterns of serum testosterone (T) and luteinizing hormone (LH) were examined in the present study. Subjects with MP-AH lesions (MP-AH subjects) had a pubertal rise in serum T almost 2 months before subjects with sham lesions (SHAM subjects). Subsequently mean serum T of MP-AH subjects rose to levels significantly higher than those of SHAM subjects before falling back to the normal 3-4 ng/ml range of SHAM subjects at 10 months. There was no apparent relationship between secretion of LH and the acceleration and enhancement of serum T. These observations indicate that there can be impairment of male sexual behavior with lesions that accelerate and enhance sexual functioning in other respects.
Animals↗
Effects of medial preoptic-anterior hypothalamic lesions on development of sociosexual behavior in dogs.
Bilateral medial preoptic-anterior hypothalamic lesions in adult male dogs eliminate or impair copulatory behavior and reduce urine-marking responses but do not affect aggressive behavior. The present study examined the emergence of the adult forms of these same male sociosexual behavioral patterns when the lesions are made prior to puberty. The subjects were allowed to interact with male peers during development. Animals with lesions had reduced frequence of juvenile mounting and an almost total absence of male copulatory activity in adulthood. Urine-marking and aggressive behavior in the juvenile and adult periods were not affected by the lesions. The findings reveal a sparing of function with regard to urine-marking but not sexual behavior.
Aggression↗
Serum testosterone of neonatal male and female dogs.
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Animals↗
Intermittent stress in pigs: effects on behavior, pituitary-adrenocortical axis, growth, and gastric ulceration.
Ninety-six pigs, half females and half castrated males from 12 litters, were housed in 24 groups of four litter mates. From an age of 115 days half of the groups were subjected to chronic stress for 33 days consisting of a schedule of unpredictable, inescapable electroshocks, and half served as controls. Behavior and performance were measured on all animals in the group, hormone data on one female in each group, and data on ulceration on the castrates. Behaviorally, the pigs did not habituate to 31 days of stress treatment. One to 2 days of stress treatment produced a behavioral activation that after 9 to 10 days was restricted to the time period of potential stress treatment. After 30 to 31 days it was replaced by passive behavior. In the beginning as well as after 30 to 31 days of intermittent stress, time spent sitting was increased. In addition, 6 days of intermittent stress reduced the baseline mean of plasma ACTH. After 33 days of stress the baseline mean of plasma ACTH was normalized, but the time course of diurnal secretion of ACTH was shifted. No effects of the chronic intermittent stress on basic levels of plasma cortisol, performance, or gastric ulceration were evident. In conclusion, the effect of intermittent stress depends on the number of days of intermittent stress treatment and it does not inevitably include changes in the basic levels of cortisol. Thus, assessment of stress must be based on a wide range of variables describing the process.
Adrenocorticotropic Hormone↗
Alternative microbial testing: a novel DNA-based detection system for specified microorganisms in pharmaceutical preparations.
Fluorescence-coupled PCR technology was employed to quantify DNA segments specific for Staphylococcus aureus, Pseudomonas aeruginosa, and Enterobacteriaceae. The PCR procedure is put forward as an alternative method for detecting microbial contaminations in pharmaceutical preparations and is compared to the tests for specified microorganisms described in European Pharmacopoeia (EP) 2, 2.6.13 and the USP, chapter 61. Data presented here describe the validation of this analytical method when used for proof of absence of specified microorganisms. The detection systems were specific for the microorganisms analyzed, and led to linear results over a wide range (more than 6-7 log intervals). The correlation coefficients lay above 0.99. The precision of replicate determinations within a single test was observed to be high, the relative standard deviation being between 0.39% and 1.53%. The precision between different tests was also high, with a relative standard deviation between 0.76% and 1.91%. The sensitivity without pre-enrichment amounted to 1-10 CFU. Since determination of the specified bacteria was performed following pre-enrichment, the limit of detection amounted to 1 CFU. Equivalent results were obtained in a study on nine batches of a milky hydrophilic cream (SH-No. M 440 A) with the conventional test for microbial contamination and the PCR procedure. The data presented here strongly indicate that the use of fluorescence-coupled PCR techniques can prove the absence of specified bacteria faster and more efficiently than conventional methods.
DNA, Bacterial↗