Biology subjects

Gnanadesikan, G. E.

Publications and source records attributed to Gnanadesikan, G. E..

4 recordsLinked to original sources

bioRxiv2025

Maternal care and early rearing environment influence puppy behaviour and cognition

Relatively little is known about the influence of maternal care on dog behaviour, despite the prominence of dogs in our lives and the established importance of early experiences in other species. While recent observational research has begun to document associations between canine maternal behaviour and later offspring outcomes, there is still much to learn--particularly regarding what factors impact maternal behaviour and the enduring effects of maternal care on puppy behavioural development. Understanding how early experiences shape future behaviour is of practical importance for companion and working dogs. We characterized the early rearing environment of 235 individual puppies from 59 litters bred by a service dog provider and explored whether offspring cognitive and behavioural traits through 16 months of age were associated with early mothering behaviour. We also investigated whether maternal behaviour could be predicted by pre-pregnancy dam behaviour and how the rearing location (private home or professional breeding centre) influenced maternal behaviour and/or puppy behaviour. We identified dam behavioural characteristics measured pre-pregnancy that were related to subsequent maternal care. While time of year was associated with maternal behaviour scores, parity, litter size, breed composition, and rearing location were not. We found that rearing location was related to puppy performance on the Dog Cognitive Development Battery (DCDB) at 8 weeks of age. Finally, maternal behaviour was associated with certain puppy cognitive and behavioural measures, assessed via the DCDB at 8 weeks of age and via questionnaires at 6, 10, 12 and 16 months of age. Our results indicate that experiences within the first few weeks of life, particularly maternal care and rearing location, may influence several aspects of dog behaviour relevant to both working and companion animals. HighlightsO_LIWe tracked early maternal interactions across 59 litters C_LIO_LISome traits measured pre-pregnancy were associated with subsequent maternal care C_LIO_LIRearing location was associated with some puppy behaviour but not maternal care C_LIO_LIMaternal care was associated with some aspects of puppy behaviour at 8 weeks C_LIO_LIMaternal care was associated with reports of puppy behaviour through 16 months C_LI

animal behavior and cognition↗

bioRxiv2022

What are oxytocin assays measuring? Epitope mapping, metabolites, and comparisons of wildtype & knockout mouse urine

Oxytocin has become a popular analyte in behavioral endocrinology in recent years, due in part to its roles in social behavior, stress physiology, and cognition. Urine samples have the advantage of being non-invasive and minimally disruptive to collect, allowing for oxytocin measurements even in some wild populations. However, methods for urinary oxytocin immunoassay have not been sufficiently optimized and rigorously assessed for their potential limitations. Using samples from oxytocin knockout (KO) and wildtype (WT) mice, we find evidence of considerable interference in unextracted urine samples, with similar distributions of measured oxytocin in both genotypes. Importantly, although this interference can be reduced by a reversed-phase solid-phase extraction (SPE), this common approach is not sufficient for eliminating false-positive signal on three immunoassay kits. To better understand the source of the observed interference, we conducted epitope mapping of the Arbor Assays antibody and assessed its cross-reactivity with known, biologically active fragments of oxytocin. We found considerable cross-reactivity (0.5-52% by-molarity) for three fragments of oxytocin that share the core epitope, with more cross-reactivity for longer fragments. Given the presence of some cross-reactivity for even the tripeptide MIF-1, it is likely that many small protein metabolites might be sufficiently similar to the epitope that at high concentrations they interfere with immunoassays. We present a new mixed-mode cation-exchange SPE method that minimizes interference--with knockout samples measuring below the assays limit of detection--while effectively retaining oxytocin from the urine of wildtype mice. This method demonstrates good parallelism and spike recovery across multiple species (mice, dogs, sifakas, humans). Our results suggest that immunoassays of urine samples may be particularly susceptible to interference, even when using common extraction protocols, but that this interference can be successfully managed using a novel mixed-mode cation exchange extraction.

neuroscience↗

bioRxiv2021

Early-Emerging and Highly-Heritable Sensitivity to Human Communication in Dogs

Dogs exhibit similarities to humans in their sensitivity to cooperative-communicative cues, but the extent to which they are biologically prepared for communication with humans is heavily debated. To investigate the developmental and genetic origins of these traits, we tested 375 eight-week-old dog puppies on a battery of social-cognitive measures. We hypothesized that if dogs social skills for cooperating with humans are biologically prepared, then these skills should emerge robustly in early development, not require extensive socialization or learning, and exhibit heritable variation. Puppies were highly skillful at using diverse human gestures and we found no evidence of learning across test trials, suggesting that they possess these skills prior to their first exposure to these cues. Critically, over 40% of the variation in dogs point-following abilities and attention to human faces was attributable to genetic factors. Our results suggest that these social skills in dogs emerge early in development and are under strong genetic control. Highlights - Genetic factors account for nearly half of variation in dog social skills - Puppies displayed social skills and interest in human faces from 8 weeks old - Puppies successfully used human gestures from the very first trial

animal behavior and cognition↗

bioRxiv2021

Cooperative Communication with Humans Evolved to Emerge Early in Dogs

While we know that dogs evolved from wolves through a process of domestication, it remains unclear how this process may have affected dog cognitive development. Here we tested dog (N=44) and wolf (N=37) puppies, 5-18 weeks old, on a battery of temperament and cognition tasks. Dog puppies were more attracted to humans, read human gestures more skillfully and made more eye contact with humans than wolf puppies. The two species were similarly attracted to objects and performed similarly on nonsocial measures of memory and inhibitory control. These results demonstrate the role of domestication in enhancing the cooperative communication skills of dogs through selection on attraction to humans, which altered developmental pathways. One Sentence Summary Domestication altered dogs developmental pathways to enhance their cooperative communication with humans.

animal behavior and cognition↗