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Biomedical subjects

R H Porter

Publications and source records attributed to R H Porter.

At least 73 records · Page 4Linked to original sources
PubMed1984

Development of olfactory bulb organization in precocial and altricial rodents.

The structural organization of the olfactory bulbs of spiny mice, Norway rats and Mongolian gerbils was followed over the course of their development. The pups of all 3 species normally begin to approach the odor of their dams at a time when their olfactory bulbs are at a similar stage of development. The data suggest that there may be a common aspect of olfactory bulb development that underlies the onset of olfactory guided approach behavior in rodents.

Animals↗
PubMed1984

Paternal behavior in the spiny mouse (Acomys cahirinus).

The responsiveness of adult male spiny mice (Acomys cahirinus) to both their own and alien precocial young was investigated. Paternal behavior was manifested primarily by the males huddling with their offspring and the coordination of pup attendance between adult males and females. With less than 2 days exposure to their own neonates, males were found to discriminate between their own and alien young. Experience plays an important role in the development of paternal behavior in spiny mice. Males who have never had pups of their own sniff and attack unfamiliar neonates more than males who have fathered pups. The adaptive significance of paternal investment in this uniquely precocial murid rodent was discussed.

Adaptation, Biological↗
PubMed1984

Recognition of neonates by facial-visual characteristics.

A series of experiments investigated the salience of newborn infants' facial-visual features for recognition and sex identification. Within 33 hours post-partum, mothers recognized photographs of their own offspring when presented with those of unrelated neonates. Furthermore, adult subjects were able to match photographs of unfamiliar mothers and their infants, and determine the sex of neonates, at a greater than chance level of accuracy. Although recognizable facial features are presumably genetically determined, maternal recognition of offspring probably results from brief exposure and familiarization as well as physical resemblance between the infant and other familiar family members, including the mother herself.

Adolescent↗
PubMed1983

Maternal recognition of neonates through olfactory cues.

The role of olfactory cues in maternal recognition of neonates was investigated. Mothers were able to identify the garments worn by their own infants (in comparison to garments worn by unfamiliar infants) through odor alone within the first 6 days postpartum. In a second experiment, mothers who had only limited pre-test exposure to their infants recognized the odor of their infant's garment during tests conducted at 20.5-41.7 hr after delivery. Olfaction may be an especially salient modality for recognition of infants.

Cesarean Section↗
PubMed1981

Experiential influences on the development of huddling preferences and "sibling" recognition in spiny mice.

The role of experience in the development of huddling preferences and sibling recognition by spiny mouse (Acomys cahirinus) weanlings was investigated. In the 1st experiment, pups separated from their littermates and fostered onto unfamiliar females (and their offspring) on the day of birth, Day 10, or Day 20, subsequently showed preferential huddling with their foster littermates. Huddling by biological siblings was as infrequent as huddling by unrelated, unfamiliar agemates. The 2nd study revealed that the mother may play a role in the ontogeny of sibling recognition, possibly through distinctive labeling of her offspring. We conclude that recognition of littermates develops through experience in the home cage in the absence of an inborn ability to recognize one's biological siblings.

Aging↗
PubMed1980

Peer preferences of at-risk and normally developing children in a preschool mainstream classroom.

Social interactions and peer preferences in a preschool mainstream classroom containing normally developing and at-risk children were studied using the ethological method of direct observation. Data on social play and on gaze orientation indicated that normally developing children and at-risk children interacted primarily with children from the same group (other normally developing and at-risk children, respectively). Data on selection on game partner and on preference of seat neighbor, however, revealed peer preference by normally developing children only. The findings were discussed as having theoretical implications for using direct observation vs. the more traditional sociometric methods for studying social adaptation in the mainstream classroom and as having practical implications for mainstreaming at risk-preschoolers.

Child Development↗
PubMed1979

Responses of spiny mouse weanlings to conspecific chemical cues.

Twenty-five-day-old A. cahirinus pups (weanlings) were tested for their responses to chemical cues produced by various classes of conspecific agemates. In Experiment 1, both male and female pups preferred bedding soiled by weanlings of either sex over clean bedding material. Subsequent experiments indicate that male but not female weanlings prefer chemical cues emanating from littermates over comparable stimuli from unfamiliar agemates. Also, chemicals produced by agemates maintained on the same diet as the animals were preferred by weanlings of either sex over cues from unfamiliar-diet weanlings. At weanlings, as for other periods of development, the individual's responsiveness to conspecific chemical cues is probably a function of age-specific environmental and social demands and the salience of various classes of conspecifics for ultimate reproductive success.

Animals↗
PubMed1978

Treatment of hypoparathyroid patients with chlorthalidone.

In an effort to maintain normal serum calcium levels without inducing hypercalciuria, we treated seven hypoparathyroid patients for up to 25 months with chlorthalidone, a thiazide-like sulfonamide diuretic, plus a salt-restricted diet, without added vitamin D. Mean 24-hour calcium excretion decreased from 179 to 88 mg (P less than 0.001), and mean serum calcium increased from 8.2 to 9.3 mg per deciliter (P less than 0.05). Diuretic therapy or moderate salt restriction alone was not as effective as combined therapy. Beneficial effects were sustained for as long as therapy was maintained. The rise in serum calcium, which involves the filterable and ionized fractions, cannot be due entirely to reduced excretion and may in part be explained by increased intestinal absorption. Oral chlorthalidone plus a low salt diet appears to be an effective alternative to vitamin D in the maintenance therapy of at least some patients with hypoparathyroidism.

Administration, Oral↗
PubMed1978

The role of diet in mother-infant reciprocity in the spiny mouse.

One-day-old spiny mouse pups responded preferentially to bedding soiled by lactating conspecifics fed the same diet as their mothers. Following this test, pups were fostered onto different-diet females. When retested at 84-96 hr of age, no preferences were shown for bedding soiled by a female fed the biological mother's diet vs bedding of a female fed the different diet. When tested again at 120-132 hr of age, however, the pups preferred the bedding associated with their foster mothers' diet. In a 2nd experiment, recently parturient females retrieved 1-day-old pups born of same-diet females faster than pups born to novel-diet females. These results indicate that pup preferences for chemical cues produced by lactating conspecifics can be altered by sufficient exposure to a 2nd female maintained on a different diet and that neonatal chemical cues, like maternal chemical stimuli, are diet-dependent.

Animals↗
PubMed1977

Dietary-dependent cross-species similarities in maternal chemical cues.

Acomys cahirinus pups preferred chemical cues from conspecific lactating females maintained on the maternal diet as compared to such cues from females fed an unfamiliar diet. Likewise, chemical cues from maternal diet Mus musculus were preferred over those from unfamiliar diet conspecific females. Thus, the production of maternal chemical stimuli may be basically similar in Acomys and Mus, with maternal diet being more critical than genetically programmed species-specific characteristics in determining the properties of the chemical cues to which A. cahirinus pups respond.

Animals↗
PubMed1976

Sex-differences in the agonistic behavior of spiny-mice (Acomys cahirinus).

Observations of 8 groups each containing three adult spiny mice (Acomys cahirinus) revealed that instances of chasing and physical displacement were quite common, while fighting and biting were rarely observed. The relationships between the most frequent behavioral categories were presented in a correlation matrix. In a second study, females tested in their home cages were dominant over males. In the males' home cages, however, no differences in the frequency of female vs. male aggression were observed. More instances of aggression were observed in the cages of the females than in the cages of the males.

Aggression↗