Biomedical subjects

G Manteuffel

Publications and source records attributed to G Manteuffel.

At least 19 recordsLinked to original sources

PubMed2007

Altered vocalization rate during the estrous cycle in dairy cattle.

Correct detection of estrus is a problem in dairy herds. In practice, several procedures exist for detection of estrus besides conventional visual observation by humans. These procedures deliver very different results regarding detection of estrus. It is known that the calls of female mammals can contain information about reproductive status. It is also suspected that the vocalizations of cattle contain information about age, sex, dominance status, and stage in the estrous cycle. In the present study, a methodology for the continuous automatic recording of vocalization of heifers during the periestrous period is presented. It was shown in 10 tethered heifers that the estrous climax results in an increase in vocalization rate. Vocalization rate of heifers increased approximately 84% from d -2 to 0 (related to observed estrus) and approximately 59% from d -1 to d 0. After d 0, vocalization rate decreased about 79%. Increased vocalization was correlated with the visual observation of estrus by humans. We also found 2 different structures in the vocalization of heifers. The harmonic structure showed regular frequency bands, whereas the nonharmonic structure was noisy. The hypothesis that the disharmonic structure increases near the estrous climax was confirmed. Hence, it seems possible to get information about stage of the estrous cycle of dairy cattle by means of monitoring vocalization. The presented method of automatically detecting the rate of cattle vocalization (patent pending) could be used solely or in combination with other automated systems for detecting estrus and could considerably increase current estrus detection rates once its applicability can be demonstrated in nontethered cattle.

Animals↗

PubMed2006

Effects of attention and rewarded activity on immune parameters and wound healing in pigs.

Challenging animals with a demanding situation they are able to cope with and where they are rewarded may be a source of positive emotions and possibly of increased welfare. In order to test if this results in changes of immunological parameters and wound healing, 56 pigs (7-20 weeks of age), housed in groups of 8 animals each, were successfully trained to recognize and localize an individual acoustic summons and to receive a small portion of feed as a reward. Immune reactions and the development of a standardized biopsy wound were compared to values of conventionally fed control groups of equal size and animal-to-feeding-place ratio (2:1). In the experimental animals a significantly higher concentration of IgG as well as an increased in vitro T-cell proliferation to ConA but a reduced LPS-induced proliferation of B-cells was found, while basal salivary cortisol concentrations were similar. Wound development was better in the experimental animals as measured by the area of the inflammatory corona. It decreased more rapidly in the experimental animals since the 5th day after biopsy and was significantly smaller than in the control groups. We conclude that environmental enrichment by equipment provoking attention and cognitive activity which is rewarded by feed may play a beneficial role for physical welfare of intensively housed pigs.

Animal Feed↗

PubMed2005

[Reaction of muscles to a stimulating environment--effects on the loin muscle (M. longissimus) of Landrace pigs].

The effects of an enriched environment on growth, meat quality, and muscle biological traits were investigated using 64 castrated pigs (age range 7 to 20 weeks). Positive emotional appraisal was induced by a system that acoustically frequently called individuals out of a group (n=32) to a feeding station, where they were rewarded with small portions of feed. The results were compared with traditional fed pigs (Control; n = 32). There was no environmental effect on live weight and lean muscle percentage. However, the stimulating keeping regime reduced the intramuscular fat content of the M. longissimus by 0.2 % and increased the protein content by 0.5 %. Moreover, the drip loss of M. longissimus was 1.1 % lower in the treatment group. The analysis of muscle fibre traits (biopsy samples of M. longissimus) showed a 7 % higher proportion of oxidative muscle fibres in the pigs reared in the enriched environment. This fibre type showed a tendency to increased fibre areas. These findings indicate a higher oxidative capacity of the muscle. However, the activity of the inarker enzyme citrate synthase (CS) was not influenced and the activity of lactate dehydrogenase (LDH) was even increased compared to the control animals.

Adaptation, Physiological↗

PubMed2004

Visual discrimination learning in dwarf goats and associated changes in heart rate and heart rate variability.

We studied visual discrimination learning in a group of Nigerian dwarf goats using a computer-based learning device which was integrated in the animals' home pen. We conducted three consecutive learning tasks (T1, T2 and T3), each of which lasted for 13 days. In each task, a different set of four visual stimuli was presented on a computer screen in a four-choice design. Predefined sequences of stimulus combinations were presented in a pseudorandom order. Animals were rewarded with drinking water when they chose the positive stimulus by pressing a button next to it. Noninvasive measurements of goats' heartbeat intervals were carried out on the first and the last 2 days of each learning task. We analysed heart rate (HR) and heart rate variability (HRV) of resting animals to study sustained physiological effects related to general learning challenge rather than acute excitement during an actual learning session. The number of trials to reach the learning criterion was 1000 in T1, when visual stimuli were presented to the goats for the first time, but decreased to 210 in T2 and 240 in T3, respectively. A stable plateau of correct choices between 70% and 80% was reached on Day 10 in T1, on Day 8 in T2 and on Day 6 in T3. We found a significant influence of the task and of the interaction between task and day on learning success. Whereas HR increased throughout T1, this relationship was inverted in T2 and T3, indicating different effects on the HR depending on how familiar goats were with the learning task. We found a significant influence of the task and the interaction between task and time within the task on HRV parameters, indicating changes of vagal activity at the heart. The results suggest that changes in HR related to learning were predominantly caused by a withdrawal of vagal activity at the heart. With regard to nonlinear processes in heartbeat regulation, increased deterministic shares of HRV indicated that the animals did not really relax until the end of T3. Comparing changes of HR and HRV in T3 and in a subsequent postexperiment (PE), we assume a positive effect of such cognitive challenges once the task had been learned by the animals.

Animals↗

PubMed2003

Effects of prenatal stress on corticosteroid receptors and monoamine concentrations in limbic areas of suckling piglets (Sus scrofa) at different ages.

The present study was conducted in order to reveal the effects of prenatal stress on the central stress regulation in domestic pigs by measuring changes in corticosteroid receptor binding and monoamine concentrations in different limbic brain regions. Pregnant sows were subjected to a restraint stress for 5 min daily during the last 5 weeks of gestation. Maternal stress resulted in a significantly higher number of glucocorticoid receptors in the hippocampus, but decreased glucocorticoid receptors in the hypothalamus of the offspring at the first postnatal day. No alterations of hippocampal mineralocorticoid receptors were found. There was also no significant effect of prenatal stress on the brain monoamine concentrations. Prenatally stressed piglets showed lower basal plasma cortisol and increased corticosteroid binding globulin concentrations at the third postnatal day indicating decreased free cortisol concentrations after birth. Morbidity and mortality during the suckling period were significantly increased in prenatally stressed litters, as shown by a higher frequency of diseased and died piglets per litter. In conclusion, the results indicate that in pigs restraint stress during late gestation affects the ontogeny of the foetal neuroendocrine feedback system with consequences for the regulation of the hypothalamo-pituitary-adrenal function and the vitality of the offspring.

Adrenocorticotropic Hormone↗

PubMed2003

[Effects of muscle needle biopsy on parameters of humoral and cellular immunity in pigs].

The shot biopsy is a common experimental technique for the collection of samples to investigate muscle tissue characteristics or to determine meat quality features in pigs. Its application seems to be also possible in interdisciplinary research projects investigating animal stress, behaviour, and welfare. The present study on 12 group-housed pigs (age: 12 weeks, weight: 29.3 kg) shows the influence of this wound-causing technique on different humoral and cell-mediated parameters of the immune system at 1, 3, 5, and 9 days after biopsy compared to the initially investigated levels before. An enhancement of the blood sedimentation rate and both the IgG and the cellular immune response in vivo (leukocytes, lymphocytes) as well as in vitro (ConA) was observed. Furthermore, there were signs of a secondary wound infection 5 days after biopsies were taken possibly caused by mutual oral manipulation of the animals. We conclude that the muscle shot biopsy technique can be used on group-housed pigs as a method to investigate muscle physiological characteristics. The technique, however, induces immunological reactions which may interfere with stress-induced immune reactions.

Animals↗

PubMed2001

Linear prediction coding analysis and self-organizing feature map as tools to classify stress calls of domestic pigs (Sus scrofa).

It is assumed that calls may give information about the inner (emotional) state of an animal. Hence, in the last years sound analysis has become an increasingly important tool for the interpretation of the behavior, the health condition, and the well-being of animals. A procedure was developed that allows the characterization, classification, and visualization of the cluster structures of stress calls of domestic pigs (Sus scrofa). Based on the acoustic model of the sound production the extraction of features from calls was performed with linear prediction coding (LPC). A vector-based self-organizing neuronal network was trained with the determined LPC coefficients, resulting in a feature map. The cluster structure of the calls was then visualized with a unified matrix and the neurons were labeled for their input origin. The basic applicability of the procedure was tested by using two examples which were of special interest for a possible evaluation of the normal farming practice. The procedure worked well both in discriminating individual piglets by their scream characteristics and in classifying pig stress calls vs other calls and noise occurring under normal farming conditions.

Acoustics↗

PubMed1998

Effects of weaning and restraint stress on glucocorticoid receptor binding capacity in limbic areas of domestic pigs.

Changes in glucocorticoid receptor (GR) binding in different brain areas were investigated in neonatal and adult pigs exposed to psychological stress (weaning) and a physical stressor (repeated snaring). The GR binding was significantly decreased 4 days after weaning in both the hippocampus and the amygdala, but there were no changes in the hypothalamus. Repeated snaring of adult pigs resulted in a significant diminished GR binding only in the hippocampus.

Animals↗

PubMed1998

An automated training device for pattern discrimination learning of group-housed gerbils.

The setup, designed for the rodent Meriones unguiculatus (gerbil), allows flexible stimulus presentations and rewarding as well as on-line data registration. It consists of a spacious housing where the animals have free access to water. Food is supplied exclusively in the y-maze training compartment and serves as a reinforcer in an operant conditioning paradigm.

Animals↗

PubMed1993

A model of the saccadic sensorimotor system of salamanders.

A model of the saccadic system of salamanders on the basis of electrophysiological and anatomical results is presented. The model includes centers found to be significant for the guidance of saccades in these comparatively simple vertebrates. In particular, these are the optic tectum, the bulbar reticular formation and the motor system. The latter consists of two pairs of neck-muscles, an epaxial and a hypaxial one driven by their respective motoneurons. The model includes a visual, a sensori-motor, and a motor level. At the sensory level, the retinal coordinates are transferred to the optic tectum to establish an orthogonal map of visual angles. A secondary visual map of the ipsilateral eye with a pointsymmetrical organization exists in addition. The premotor system of the tectum was modelled according to an ensemble-coding principle. Thus, local activation of the visual map results in recruitment of an appropriate number of tectal premotor units. Simulation of the model reproduces correct metric properties of salamander saccades under varying stimulus presentations.

Animals↗

PubMed1990

Quantitative distribution of descending tectal efferent cells in salamanders.

In salamanders of the species Salamandra salamandra, Pleurodeles waltl, and Plethodon jordani, tectal efferent neurons projecting to the bulbar reticular formation show a stereotyped distribution as revealed by the horseradish peroxidase (HRP) method. The density of these cells increases toward caudal tectal levels reaching its maximum at the isthmic region. Neurons with ipsilaterally descending axons constitute 60-87% and are concentrated in the dorsomedial and ventrolateral sector of the tectal hemisphere, with only few neurons in the intermediate part. The contralaterally descending neurons are concentrated in the lateral sector. This pattern is assumed to reflect a motor map in the coordinates of the salamander neck muscle system.

Animals↗

PubMed1990

Configuration-sensitive visual responses in the superior colliculus of the house mouse (Mus musculus domesticus).

In order to compare visual pattern discrimination by tectal neurons in distantly related vertebrate groups, collicular cells of mice were examined for their responses to each of three simple configurational stimuli commonly used in studies of amphibians. The stimuli consisted of a large square, a horizontal bar and a vertical bar moved at various velocities. Of the recorded units (n = 51), 30-50% significantly preferred the square to the other stimuli at medium (10 degrees/s) and high (67 degrees/s) velocities. Approximately 10% preferred the horizontal bar at these velocities. A significant discrimination between the horizontal and the vertical bar was found in 39% of the units at a velocity of 10 degrees/s, and in 61% at a velocity of 67 degrees/s. These response types are very similar to those found in amphibians; therefore, it is concluded that tectal configurational sensitivity may be a plesiomorphic tetrapod character resulting from basic properties of tectal neuronal circuitry.

Animals↗

PubMed1990

Anatomical connections and electrophysiological properties of toral and dorsal tegmental neurons in the terrestrial urodele Salamandra salamandra.

Fire salamanders (Salamandra salamandra) are strictly terrestrial urodele amphibians, having lost electroreception and the lateral line system during metamorphosis. The present study demonstrates that (i) the lateral lemniscus is supplied by fibers of the medullary acoustic nucleus (nucleus intermedius) and the superior olive; (ii) the subtectal dorsal tegmentum can be clearly separated into a dorsally located torus semicircularis and a ventrally situated dorsal tegmental nucleus, the former processing auditory and vibratory, the latter vestibular signals; and (iii) the hearing capabilities of this animal, as estimated from the tuning of toral units, are comparable to those of anurans with extratympanic sound transmission. It is concluded that vibration sensitivity and hearing are involved in defensive reactions in the non-vocalizing fire salamander. The vestibular cells in the dorsal tegmentum probably relay a head-velocity input to the optic tectum, thus providing a self-motion signal for the visual localization center.

Action Potentials↗

PubMed1989

Topographic relationships of ipsi- and contralateral visual inputs to the rostral tectum opticum in the salamander Plethodon jordani indicate the presence of a horopter.

Topographies of ipsilateral and contralateral retinal inputs to the optic tectum were studied by means of electrophysiological multi-unit recordings from the superficial layers. It was found that the nasotemporal coordinate of the visual field is represented along a rostrocaudal axis on the contralateral tectal map and along a caudorostral axis on the ipsilateral map. Electrical stimulation of one tectal hemisphere and recording of the response in the other hemisphere revealed that the ipsilateral map is most probably established by an intertectal pathway. In one tectal hemisphere, inputs from the ipsilateral eye match those from the contralateral eye if stimuli are located at a certain distance at arbitrary horizontal angles within the binocular field. This distance varied from 11.8 to 29.5 mm between the 5 individuals examined.

Animals↗

PubMed1988

Origins of descending projections to the medulla oblongata and rostral medulla spinalis in the urodele Salamandra salamandra (amphibia).

Descending projections to the medulla oblongata and rostral medulla spinalis have been examined in the urodele Salamandra salamandra with retrograde horseradish peroxidase tracing. Ipsilateral projections originate from the striatum and the nucleus ventrolateralis thalami and reach the medulla oblongata. The ipsilateral nucleus praeopticus magnocellularis reaches the medulla spinalis. The rostral part of the nucleus tuberculi posterioris projects to the ipsilateral medulla oblongata; its caudal part projects further caudally. Tectal efferents and the efferents of the nucleus praetectalis profundus project bilaterally, the nucleus praetectalis superficialis, nucleus mesencephalicus nervi trigemini, torus semicircularis, nucleus Darkschewitsch, and nucleus fasciculi longitudinalis medialis project ipsilaterally to the medulla oblongata. The nucleus mesencephalicus nervi trigemini, nucleus fasciculi longitudinalis medialis, and tectal efferents reach the rostral medulla spinalis. The nucleus ruber projects mainly via the contralateral dorsolateral funiculus to the medulla spinalis. A largely crossed medullary projection arises in the nucleus dorsalis tegmenti pars anterior, a bilateral projection arises in the nucleus dorsalis tegmenti pars posterior, and an ipsilateral projection arises in the nucleus ventralis tegmenti pars anterior. Cerebellar and statoacoustic efferents descend to the medulla spinalis. The nucleus reticularis isthmi, superior, medius and inferior as well as the nucleus raphes exhibit spinal trajectories. The nucleus vestibularis magnocellularis projects bilaterally, the nucleus vestibularis medialis projects ipsilaterally spinalward. The supposed nucleus descendens nervi trigemini descends mainly contralaterally. A small spinal projection arises in the nucleus tractus solitarii. The results indicate that salamander brains display elaborate descending connections which are similar to those in other vertebrates despite their scarcely differentiated neuronal cytoarchitecture.

Animals↗

PubMed1987

Binocular afferents to the salamander pretectum mediate rotation sensitivity of cells selective for visual background motions.

The majority (85%) of background motion-sensitive pretectal cells in salamanders was found to be binocularly driven. In 70% of the units the binocularity establishes a rotation selectivity with respect to background pattern-movements. This results in a considerable augmentation of the discharge rate when pattern movement is perceived simultaneously in the temporonasal direction by the contralateral eye and nasotemporally by the ipsilateral eye. The response is depressed when the pattern movement is seen in the same direction by both eyes. It is concluded that the rotation-sensitive cells are mainly excited by contralateral retinal afferents selective for temporonasal movements and inhibited by direct or indirect ipsilateral afferents with the same type of direction selectivity.

Afferent Pathways↗

PubMed1987

Directional selectivities of visual afferents to the pretectal neuropil in the fire salamander.

Single-unit recordings from visual afferents in the pretectal neuropil of Salamandra salamandra were performed to characterize the properties of direction specific units which are probably involved in the optokinetic reflex. It was shown that afferents from the contralateral eye were more sharply tuned than those from the ipsilateral eye. However, the majority of both were selective for temporonasal movements.

Animals↗

PubMed1987

Optic inputs to identified neck-muscle motoneurons of Salamandra salamandra (L.): an intracellular recording study.

By means of retrograde horseradish peroxidase (HRP) transport, motoneurons innervating the musculus intertransversarius capitis superior (m.i.c.s.) of Salamandra salamandra (L.) were labeled from the level of the vagus nerve to the fourth spinal nerve. The bulk of the neurons was situated between the first and the third spinal nerve. The HRP-labelings revealed smaller cells with one apical dendrite and large cells with two main dendrites originating from opposite poles of the soma. With intracellular recordings from m.i.c.s. motoneurons a bimodal distribution of the antidromic latencies was found after intramuscular electrical stimulations. Optic inputs to the motoneurons were examined with electrical stimulation of the optic discs. It was shown that the majority of optic signals to the motoneurons originate from the contralateral eye. The latency distribution of these inputs suggests that most of the signals reach the motoneurons via indirect pathways involving at least one additional synapse. However, a few motoneurons seemed to be directly coupled with visual centers.

Animals↗