Early recognition of newborn goat kids by their mother: I. Nonolfactory discrimination

Mother sheep and goats develop an early bond with their neonate on the basis of olfactory recognition. We investigated whether goats were also able to show early (<24 hr postpartum) nonolfactory discrimination of their kids, as already reported in sheep. In a first experiment, we found that goats are not able to recognize their kid at 1 m away on the basis of olfactory cues alone. By contrast, they showed a significant preference for their own kid in a two-choice test as early as 4 hr postpartum, and prepartum maternal anosmia did not impede the ability of mothers to show discrimination. We conclude that goats, like sheep, are fully able to discriminate their neonate without the help of olfactory cues very early after parturition. The difference in the early spatial mother-young relationship between the two species due to the different behavior of the young (kids = hiders, lambs = followers), is not associated with marked differences in the dynamics or mechanisms controlling the development of recognition of the neonate by its mother.     

Establishment of vocal communication and discrimination between ewes and their lamb in the first two days after parturition

In sheep, the mother-young relationship is characterized by an exclusive bond that relies on the rapid establishment of mutual recognition. However, the role of acoustic cues has been underestimated and neglected in this early discrimination. Therefore, the aim of the present study was (1) to characterize the vocal behavior of ewes and their lambs during the first 15 days postpartum and (2) to investigate the ability of newborn lambs and their mothers to discriminate each other from alien subjects within the first 48 hr postpartum on the basis of acoustic cues only. Ewes started to vocalize in the last 3 hr preceding parturition, emitting mainly high-pitched bleats. However, the bleating activity was highest during the first 3 hr following birth, consisting mainly of low-pitched bleats. Thereafter it decreased sharply until 24 hr postpartum, with most of the activity coming from the mother. In a two-choice test, ewes discriminated their own from an alien lamb on the basis of acoustic cues only at 24 hr postpartum, while lambs did so for their mother at 48 hr, which in both cases was much earlier than reported so far. We conclude that early vocal recognition between the ewe and her lamb may play an important role for the maintenance of mother-young contact.     

Maternal experience influences the establishment of visual/auditory, but not olfactory recognition of the newborn lamb by ewes at parturition

Maternal behavior in sheep is characterized by the rapid establishment of individual recognition of the lamb through the use of different sensory modalities. Olfactory recognition mediates acceptance at suckling whereas visual/auditory cues are involved in recognition from a distance. This study investigates (a) the timing of both types of recognition and (b) whether they can be influenced by maternal experience. Olfactory recognition was assessed at lambing, 30 min, 1, 2, or 4 hr postpartum by presenting successively an alien and the familiar lamb. Recognition at a distance was assessed at 6, 8, and 12 hr postpartum by using a two-choice test between the familiar and an alien lamb. A majority (33/51) of ewes showed selectivity at suckling as early as 30 min after parturition, and no differences due to maternal experience were observed. By contrast, in the two-choice recognition test, multiparous ewes showed a preference for their familiar lamb at 6 hr whereas primiparous mothers did so only after 24 hr of mother-young contact: The performance of biparous mothers was intermediate. Thus, both types of recognition can be rapidly established after parturition, and maternal experience has a differential effect on the dynamics of these learning processes.     

Twenty-four-hour-old lambs rely more on maternal behavior than on the learning of individual characteristics to discriminate between their own and an alien mother

Lambs can discriminate their own mother from an alien dam on the first day of life, suggesting the recognition of individual physical characteristics of the mother. Alternatively, their choice may depend on behavioral differences existing between the ewes because of their maternal selectivity. To clarify this, the ability of 24-hr-old lambs to discriminate between their own and an alien mother, that were either intact and accept only their own lamb at nursing (i.e., selective, n = 19) or anosmic, which nurse indiscriminately alien lambs as well as their own (i.e., nonselective, n = 24), was assessed by a 5-min, two-choice test. With intact dams, lambs spent significantly more time next to their own mother whereas this was not so in the presence of anosmic dams. Furthermore, in the intact group, the vocal activity by their own mother differed from that by the alien dam while this was not so in anosmic ewes. We conclude that 24-hr-old lambs rely more on the behavior of the ewes to select their dam than on their individual physical characteristics.     

How the neonatal rat gets to the nipple: Common motor modules and their involvement in the expression of early motor behavior

One-day-old rat pups adopt a supine posture before attaching to the mother's nipple. Body rotations performed to reach the nipple occur in a typical kinematic structure. First, the pup rotates along the longitudinal axis of the trunk and lies on its side. Next, the pup arches the trunk to achieve a U-shaped posture and then rapidly relaxes the trunk. A second cephalocaudal rotation follows at the peak of trunk relaxation as the pup achieves a supine posture. After reaching a supine posture, the pup crawls to a nipple by performing “stepping” movements on the mother's ventral surface. The kinematic structure of these movements is reminiscent of the structure of righting as seen in the newborn rat. Both righting and achieving a supine posture under the mother involve the expression of common motor modules. During righting the modules are executed in the direction of gravity, and when achieving a supine posture the modules are executed against the force of gravity. Simple motor behaviors expressed by the rat pup during early postnatal development may have common origins and common control mechanisms. © 1998 John Wiley & Sons, Inc. Dev Psychobiol 32: 57–66, 1998     

Early use of orthographic information in spoken word recognition: Event‐related potential evidence from the Korean language

This study examines whether orthographic information is used during prelexical processes in spoken word recognition by investigating ERPs during spoken word processing for Korean words. Differential effects due to orthographic syllable neighborhood size and sound‐to‐spelling consistency on P200 and N320 were evaluated by recording ERPs from 42 participants during a lexical decision task. The results indicate that P200 was smaller for words whose orthographic syllable neighbors are large in number rather than those that are small. In addition, a word with a large orthographic syllable neighborhood elicited a smaller N320 effect than a word with a small orthographic syllable neighborhood only when the word had inconsistent sound‐to‐spelling mapping. The results provide support for the assumption that orthographic information is used early during the prelexical spoken word recognition process.     

Individual recognition of female hamsters by males: role of chemical cues and of the olfactory and vomeronasal systems

Sexually satiated male hamsters preferred to investigate and to mount an anesthetized, estrous, novel female over a similarly presented female with which the male had become satiated (the Coolidge effect); likewise, such males preferred a novel female recently mated with another male over the familiar female but showed no preference between fresh and mated novel females. Thus the Coolidge effect is at least partly dependent on discrimination of a new female by chemical cues. Another experiment indicated that transfer of a male's own scent during mating is not involved in discrimination between familiar and novel females. Flank gland secretion of females were sufficient for individual discrimination by males, whereas head region scents and vaginal secretions were not sufficient. The presence of female's flank glands was not, however, necessary for such discrimination. Lesions of or removal of the vomeronasal organ did not disrupt the preferences of sexually satiated males for a novel female, but elimination of main olfactory system function by ZnSO4 treatment of the olfactory mucosa did abolish such preferences. Thus olfactory cues are sufficient for individual discrimination of novel females by sexually satiated male hamsters, and such recognition leads to increased sexual arousal. These processes are mediated by the main olfactory system but not the vomeronasal accessory-olfactory system.     

Dopamine's role in social modulation of infant isolation‐induced vocalization: II. Maternally modulated infant separation responses are regulated by D1‐ and D2‐family dopamine receptors

Mammalian infant behavior directed toward caregivers is critical to survival and may play a role in establishing social bonds. Most mammalian infants vocalize when isolated. Rat pups vocalize at a higher rate when isolated following an interaction with an adult female than after an interaction with littermates, a phenomenon termed maternal potentiation. We previously reported that the D2 receptor family agonist quinpirole disrupts maternal potentiation at a dose that does not alter vocalization rate following contact with littermates. Here we further examine the role of dopamine in maternal potentiation by testing effects of both D1 and D2 receptor family ligands, alone and in combination, on maternal potentiation. We tested the drugs' effects on isolation vocalization subsequent to littermate contact and then another isolation preceded by a brief “reunion” period of exposure either to the anesthetized dam or a handling‐only “pickup” condition. D2 receptor stimulation blocked the increase in vocalizations following reunion with the dam. The D2 agonist effect in the dam‐reunion condition was much larger than its small effect in the pickup condition, providing further evidence that D2 receptors exert a selective modulation of maternal potentiation. On the other hand, systemic administration of the D1 agonist SKF81297 reduced isolation vocalizations nonspecifically, across all the experimental conditions. Finally, the D1 and D2 receptor dual antagonist, alpha‐flupenthixol, increased isolation vocalizations and disrupted potentiation, but at doses that also inhibited locomotion. We conclude that D2 receptor family activation has a more selective effect of disrupting maternal potentiation than D1 receptor family activation. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 51: 158–172, 2009     

Cellular recognition of foreign materials by Bombyx mori phagocytes: II. Role of hemolymph and phagocyte filopodia in the cellular reactions

The plasmatocytes and granular cells are the most important hemocyte types involved in the cellular reactions of insects. These two hemocytes are obviously characterized with the adhesive morphology. Particularly, the granular cells in Bombyx mori have many long filopodia, and they are considered to play roles in catching the foreign materials invading into the hemocoel and also in obtaining some phagocytic signals during elongation process. The second part of this mini-review is a continuation of the previous summary (1) in which the immunocompetent cells in B.mori were described. Here, possible role of hemolymph factor is presented with much attention to the filopodial function of phagocytic granular cells of B.mori.     

In vivo clearance by the mononuclear phagocyte system in humans: an overview of methods and their interpretation.

The mononuclear phagocyte system (MPS) is responsible for the elimination of foreign material, effete autologous material and immune complexes. To study the relationship between MPS function and human disease, several test substances have been developed, and used to determine the clearance capacity of the MPS in human subjects in vivo. These test substances and the multitude of factors that influence the elimination of these substances (and complicate the interpretation of the test results) are discussed. Use of these probes has provided important new insights, that may lead to the development of treatment modalities by which MPS function is modified in order to influence disease processes more effectively.     

IL-12 family members: differential kinetics of their TLR4-mediated induction by Salmonella enteritidis and the impact of IL-10 in bone marrow-derived macrophages

The members of the IL-12 family of heterodimeric cytokines play a pivotal role in initiation and regulation of cell-mediated immunity. Best known is IL-12p70, which promotes an immune response towards T(h)1 bias. Other members of this family (IL-23, IL-27) are less well characterized in terms of induction and function. Using either heat-killed or viable Salmonella Enteritidis or LPS as a stimulus, the kinetics of mRNA production of each member of the IL-12 family (p19, p28, p35, p40, Ebstein-Barr-Virus-induced gene 3 (EBI-3)) were determined in BMDMPhi originating from wild-type, Toll-like receptor (TLR)2- and/or TLR4-deficient mice. It was found that following either type of stimulation, a characteristic mRNA expression pattern was observed for each cytokine subunit. Whereas p19 was induced early and transiently, p40 and p35 were up-regulated later and then continuously, but the secretion of IL-23 and IL-12p70 was significantly reduced by IL-10. The up-regulation of p28 mRNA occurred also delayed and declined afterwards, whereas the initial high-level expression of EBI-3 remained almost unchanged in BMDMPhi. Furthermore, a splice variant of the EBI-3 mRNA was discovered. In this context, the cytokine mRNA up-regulation by whole Salmonella Enteritidis is mediated chiefly by TLR4, but depends on additional pattern recognition receptors other than TLR2 expressed by macrophages.     

Analysis of idiotope structure of ovarian cancer antibodies: recognition of the same epitope by two monoclonal antibodies differing mainly in their heavy chain variable sequences.

Two MoAbs, independently raised against ovarian carcinoma cells and referred to as OV-TL3 and OV-TL16, display an identical reaction pattern with a membrane-associated protein in both normal and malignant ovarian cells. Also, a similar binding affinity constant and a similar number of binding sites per cell indicate that both MoAbs bind to the same antigen. Competition assays reveal that OV-TL16 is able to compete with OV-TL3 for binding to OVCAR-3 cells. Epitope mapping using a filamentous phage hexapeptide epitope library showed that both MoAbs are able to select identical phages, suggesting that their epitopes are identical or at least overlapping. However, purified polyclonal and monoclonal anti-idiotypic antibodies directed against OV-TL3 failed to recognize the OV-TL16 idiotype, indicating that the structure of the antigen-binding regions of both antibodies is distinct. This was corroborated by molecular cloning and sequencing of the variable heavy (VH) and light (VL) chain immunoglobulin regions of both MoAbs. The VH regions of both antibodies were found to be distinct, whereas the VL regions are almost identical. Computer modelling of the idiotypes suggests that the complementarity determining regions (CDR), with the exception of VHCDR3, have (almost) identical spatial configurations. Our data indicate that, although structurally different in their VH regions, OV-TL3 and OV-TL16 are able to bind to identical epitopic regions on the antigen, because differences in primary structure do not exclude the formation of sufficient and similar spatial structures for the interaction with an epitope.     

Electrical stimulation of arterial and central chemosensory afferents at different times in the respiratory cycle of the cat: II. Responses of respiratory muscles and their motor nerves

The response patterns of the electrical activity of the respiratory motor nerves and muscles to brief electrical stimulation of the arterial and the intracranial chemosensory afferents were studied in anesthetized cats. Stimulation during inspiration increased the activity of phrenic nerve and the inspiratory muscles (intercostal, diaphragm) with a latency of 15–25 ms, whereas expiratory muscle activity in the following expiration remained almost unaltered. Stimulation during expiration increased the activity of expiratory nerves and muscles (intercostal, abdominal) after a delay of 80–120 ms. The later the stimulation occurred in the insor expiratory period the larger the increase in amplitude and in steepness of rise of the respective integrated activity in respiratory nerves and muscles. Stimulation in early inspiration shortened the discharge period of inspiratory muscles, whereas excitation in early expiration caused an earlier onset and prolonged the activity in the expiratory muscles. Stimulation in the late phase of ins- or expiration prolonged the discharge of the respective nerves and muscles. Both the arterial (carotid sinus nerve, CSN, and aortic nerve, AN) and intracranial chemosensory (VM) afferents stimuli were able to affect both the inspiratory and the expiratory mechanisms. The restriction of the effects to the phase of the stimulus suggests a mechanism by which these afferents, when activated during inspiration, effectively project only to inspiratory neurones, and vice versa for expiration.Supported by the Deutsche Forschungsgemeinschaft, SFB 114 Bionach     

Neurons with callosal projections in visual areas of newborn kittens: an analysis of their dendritic phenotype with respect to the fate of the callosal axon and of its target

Summary Combined retrograde transport of Rhodamine-labeled latex beads and intracellular injection of Lucifer Yellow in aldehyde-fixed slices of areas 17 and 18 in kittens indicate that neurons with similar dendritic morphology send axons into the corpus callosum from the 17/18 border and from parts of area 17 destined to become acallosal. At both sites callosally projecting neurons (callosal neurons) include pyramids, spiny stellate cells and star-pyramids; two types of pyramidal neurons can be distinguished on the basis of the complexity of their apical dendrites. At both sites, the dendritic morphology of callosal neurons appears basically unaffected by the ablation at the beginning of the second postnatal week of the contralateral areas 17 and 18 to which they have sent their axon. Thus the dendritic morphology of this type of cortical neuron seems independent of retrograde signals coming from their contralateral target and may instead depend on programs intrinsic to the neurons and/or conditions acting locally on their cell bodies, dendrites or initial axon collaterals.     

Brainstem projections of different branches of the vestibular nerve: an experimental study by transganglionic transport of horseradish peroxidase in the cat. II. The anterior and posterior ampullar nerves.

The brainstem projections of the ampullar nerves from the vertical semicircular canals, the anterior (AAN) and the posterior ampullar nerve (PAN), were studied in adult cats using the transganglionic horseradish peroxidase (HRP) method. Each nerve was exposed in three experiments. Two animals in each group had labeling which allowed detailed mapping. From the AAN, terminal-type labeling was found in two separate groups, one laterally and one medially, both in the lateral (LV) and in the superior (SV) vestibular nucleus. In addition, such labeling was found in all parts of the medial vestibular nucleus (MV). Labeled structures were found also in the descending vestibular nucleus, (DV) more densely over its lateral part, except for cell group f, where no labeling was found. From the PAN, terminal-type labeling was found medially and laterally in the LV and in the medial part of the SV. In the MV, such labeling was evenly distributed rostrally but concentrated laterally in caudal parts. In the DV, terminal-type labeling was present rostrally, whereas no labeling was seen caudally. In the interstitial nucleus of the vestibular nerve, terminal-type labeling was observed from the AAN but not from the PAN. No labeled fibers from either of the two ampullar nerves were seen outside the vestibular root and nuclei, except for small-caliber fibers from the SV heading towards the brachium conjunctivum. The findings clearly indicate a specific termination for each of the two ampullar nerves.     

Principal cells of the rat medial nucleus of the trapezoid body: an intracellular in vivo study of their physiology and morphology

The medial nucleus of the trapezoid body (MNTB) is one of several principal nuclei in the superior olivary complex (SOC) of mammals. It is classically thought to function as a relay station between the contralateral ventral cochlear nucleus and the lateral superior olive (LSO), playing a role among those brainstem nuclei that are involved in binaural hearing. In order to characterise the physiology and morphology at the cellular level of the major neuronal component of the MNTB, the principal cells, we have analysed these neurons in rats in vivo using intracellular recordings and horseradish peroxidase-labelling. Our data demonstrate that MNTB principal cells, when being stimulated acoustically via the contralateral ear, show a phasic-tonic response with an onset latency of 3.5 ms and a suppression of their spontaneous activity following stimulus offset. These neurons have an axonal morphology whose complexity has not yet been described. All cells (n=10) projected exclusively ipsilaterally and had terminal axonal arbors in a variety of auditory brainstem nuclei. At least two and maximally seven auditory targets were innervated by an individual cell. Each cell projected into the LSO and the superior paraolivary nucleus (SPN). Additional projections that were intrinsic to the SOC were often observed in the lateral nucleus of the trapezoid body and in periolivary regions, with only one cell projecting into the medial superior olive. Most, if not all, MNTB principal cells also had projections that were extrinsic to the SOC, as their axons ascended into the lateral lemniscus. In two neurons the ascending axon formed terminal arbors in the ventral nucleus of the lateral lemniscus, and the dorsal nucleus of the lateral lemniscus could be identified as a target of one neuron. The location of the cell bodies of the MNTB principal cells correlated with the neurons' best frequencies, thereby demonstrating a tonotopic organisation of the MNTB, with high frequencies being represented medially and low frequencies laterally. The axonal projections into the LSO and the SPN were also tonotopically organised and the alignment of the tonotopic axes was similar to that in the MNTB. Our results confirm previous data from other species and suggest that MNTB principal cells have a great amount of physiological and morphological similarities across mammalian species. Furthermore, the complexity of the axonal projections indicates that these neurons play a role in auditory information processing which goes far beyond their previously described classical role.     

An in vitro model of allergen-dependent IgE synthesis by human B lymphocytes: comparison of the response of an atopic and a non-atopic individual to Dermatophagoides spp. (house dust mite).

An allergen-dependent in vitro model of immunoglobulin E (IgE) synthesis by human B cells is reported. Using this model, it is demonstrated that polyclonal T cells and CD4+ Dermatophagoides spp. (house dust mite)-specific T-cell clones derived from an atopic, house dust mite (HDM)-allergic individual are able to support IgE synthesis by autologous B cells. The helper activity was interleukin-4 (IL-4) dependent as only cloned T cells expressing detectable mRNA for IL-4 were able to induce IgE synthesis without the addition of exogenous IL-4. Peripheral and cloned T cells reactive with HDM could also be identified from a non-atopic individual but neither population was able to support IgE production even in the presence of exogenous IL-4.     

Initial vascularisation in the pig placenta: II. Demonstration of gland and areola-gland subunits by histology and corrosion casts

Tissues from 10 pregnant pigs between 9 1/2 and 43 days post coitum (p.c.) were prepared for histology and vascular corrosion casts to examine the vascularisation of the gland and areola-gland subunits of the early pig placenta. The endometrial vascular networks shown by casts were equal in both glandular and interglandular fields from days 9 1/2 to 14–15 p.c. This represents a cyclic stage uninfluenced by the early implanting embryo on day 13 p.c. By day 15 p.c., the first areola formation was observed both histologically and on casts. The maternal areolar and glandular capillary network developed into a widely meshed loose type, in contrast to the interareolar type which had a dense and parallel architecture. In some cases extremely large, crooked, and highly anastomosed maternal capillaries developed between these two networks. This specialized transition is thought to form the base for the ring-like seal formation (RSF) of the areolar periphery. A firm materno-fetal anchor therefore “seals” the areola and its glandular secretory contents from its interareolar surroundings. Therefore, the glandular and maternal areolar vasculatures are clearly discernable from that of the fetal areolar vasculature. The former are associated with the known materno-fetal substance transfer of the porcine areola-gland subunit. This association, however, seems to remain unspecialized in early placentation, as only the regular roundish areola—not the irregular areola—can be distinctly detected. © 1994 Wiley-Liss, Inc.