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This article is part of a Special Issue “Parental Care”. Jay Rosenblatt effectively promoted research on rabbit maternal behavior through his interaction with colleagues in Mexico. Here we review the activities of pregnant and lactating rabbits ( Oryctolagus cuniculus ), their neuro-hormonal regulation, and the synchronization of behavior between mother and kits. Changing concentrations of estradiol, progesterone, and prolactin throughout gestation regulate nest-building (digging, straw-carrying, fur-pulling) and prime the mother's brain to respond to the newborn. Nursing is the only mother–young contact throughout lactation. It happens once/day, inside the nest, with ca. 24 h periodicity, and lasts around 3 min. Periodicity and duration of nursing depend on a threshold of suckling as procedures reducing the amount of nipple stimulation interfere with the temporal aspects of nursing, though not with the doe's maternal motivation. Synchronization between mother and kits, critical for nursing, relies on: a) the production of pheromonal cues which guide the young to the mother's nipples for suckling; b) an endogenous circadian rhythm of anticipatory activity in the young, present since birth. Milk intake entrains the kits' locomotor behavior, corticosterone secretion, and the activity of several brain structures. Sibling interactions within the huddle, largely determined by body mass at birth, are important for: a) maintaining body temperature; b) ensuring normal neuromotor and social development. Suckling maintains nursing behavior past the period of abundant milk production but abrupt and efficient weaning occurs in concurrently pregnant-lactating does by unknown factors. Conclusion: female rabbits have evolved a reproductive strategy largely dissociating maternal care from maternal presence, whose multifactorial regulation warrants future investigations. [ABSTRACT FROM AUTHOR]

Urinary tract infections and bacteriuria are common in the pediatric population, and antibiotic resistance is increasing significantly. Recurrent urinary infections, symptomatic or asymptomatic, are a risk factor for developing chronic kidney disease in adolescents and young adults. This study aimed to assess the prevalence of bacteriuria diagnosed by culture to identify the main causal agents and sensitivity to antibiotics in adolescents from the central region of the state of Tlaxcala. A cross-sectional study was carried out among 905 adolescents from 11 to 18 years old who lived in the central region of the state of Tlaxcala, Mexico. Bacteriuria was evaluated by positive nitrites and leukocyte esterase, and urine culture with antibiogram. Multivariate logistic regression models were executed to evaluate the risk of presenting bacteriuria, with a confidence level of 95%. A total of 31 participants had a positive urine culture, with a bacteriuria prevalence of 3.4%, of which 29 cases were asymptomatic. The most frequent agent was Escherichia coli) in both sexes (28.6% in men and 29.7% in women) and regarding bacterial resistance: E. coli presented greater resistance to ampicillin, trimethoprim/sulfametoxazol and ceftriaxone. The risk factors associated with bacteriuria were female sex, sexual activity, use of contraceptives, and greater consumption of sweetened beverages. Bacteriuria is common in this adolescent population, so its early identification is necessary to treat it, and to prevent its complications., (Copyright: © 2024 Permanyer.)

In this study, 40 Japanese, 44 German and 39 Mexican women were presented with 18 everyday odorants. They were asked to rate them for intensity on a six-point scale from not detectable to very strong, for pleasantness on an 11-point scale from -5, to neutral at 0, to +5, and for familiarity on a six-point scale from completely unknown to extremely familiar. Consistent positive correlations were found between paired rating scores for the three measures, and although they were not particularly strong (r(s) range, 0.19-0.60), for most odorants all three correlations were significant. Similar results were obtained whether the data were analyzed on an individual or a national basis. Most notable were the consistent positive correlations between perceived intensity and ratings of familiarity and hedonic strength. It is suggested that the perceived intensity of the odorants depended not only on stimulus concentration but probably also on experience-dependent factors.