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1.
Biochem Biophys Res Commun ; 579: 62-68, 2021 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-34587556

RESUMEN

Urocanic acid (UCA) is an endogenous small molecule that is elevated in skin, blood and brain after sunlight exposure, mainly playing roles in the periphery systems. Few studies have investigated the role of UCA in the central nervous system. In particular, its role in memory consolidation and reconsolidation is still unclear. In the present study, we investigated the effect of intraperitoneal injection of UCA on memory consolidation and reconsolidation in a novel object recognition memory (ORM) task. In the consolidation version of the ORM task, the protocol involved three phases: habituation, sampling and test. UCA injection immediately after the sampling period enhanced ORM memory performance; UCA injection 6 h after sampling did not affect ORM memory performance. In the reconsolidation version of the ORM task, the protocol involved three phases: sampling, reactivation and test. UCA injection immediately after reactivation enhanced ORM memory performance; UCA injection 6 h after reactivation did not affect ORM memory performance; UCA injection 24 h after sampling without reactivation did not affect ORM memory performance. This UCA-enhanced memory performance was not due to its effects on nonspecific responses such as locomotor activity and exploratory behavior. The results suggest that UCA injection enhances consolidation and reconsolidation of an ORM task, which further extends previous research on UCA effects on learning and memory.


Asunto(s)
Habituación Psicofisiológica/efectos de los fármacos , Aprendizaje/efectos de los fármacos , Consolidación de la Memoria/efectos de los fármacos , Reconocimiento en Psicología/efectos de los fármacos , Ácido Urocánico/farmacología , Animales , Conducta Animal , Mapeo Encefálico , Manejo Psicológico , Locomoción , Masculino , Ratones , Ratones Endogámicos ICR
2.
J Zoo Wildl Med ; 52(1): 259-267, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33827184

RESUMEN

Studies to assess wildlife health commonly evaluate clinical pathology changes, immune responses, pathogen presence, and contaminant exposure, but novel modalities are needed to characterize the unique physiologic responses of reptiles. Lactate is an indicator of hypoperfusion and/or anaerobic respiration and can be quickly and easily measured using a point-of-care analyzer. This study evaluated baseline blood lactate concentrations in free-living eastern box turtles (Terrapene carolina carolina, n = 116) using a point of care analyzer and then determined the effect of handling time, physical examination (PE) abnormalities, and quantitative polymerase chain reaction pathogen detection (Terrapene herpesvirus 1, Mycoplasma sp., Terrapene adenovirus) on lactate concentrations. Blood lactate concentrations were higher in turtles with Terrapene herpesvirus 1 (n = 11), quiet mentation, and increased packed cell volume (P < 0.05). Lactate concentrations increased between initial capture and PE, with peak values reaching 129 min after capture. Lactate at PE was positively associated with baseline lactate concentrations. Turtles with Terrapene herpesvirus 1 may have alterations in blood flow, oxygen delivery, or activity patterns, driving increases in baseline lactate. Increased handling time likely leads to more escape behaviors and/or breath holding, causing turtles to undergo anaerobic metabolism and raising lactate concentrations. Overall, lactate measured by a point of care analyzer shows variability caused by capture and health factors in eastern box turtles and may be a useful adjunctive diagnostic test in this species after full methodologic validation.


Asunto(s)
Ácido Láctico/sangre , Tortugas/sangre , Animales , Pruebas Diagnósticas de Rutina , Perros , Femenino , Manejo Psicológico , Illinois , Masculino , Sistemas de Atención de Punto , Estrés Fisiológico
3.
Gen Comp Endocrinol ; 287: 113324, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31733208

RESUMEN

There is growing interest in the use of glucocorticoid (GC) hormones to understand how wild animals respond to environmental challenges. Blood is the best medium for obtaining information about recent GC levels; however, obtaining blood requires restraint and can therefore be stressful and affect GC levels. There is a delay in GCs entering blood, and it is assumed that blood obtained within 3 min of first disturbing an animal reflects a baseline level of GCs, based largely on studies of birds and mammals. Here we present data on the timing of changes in the principle reptile GC, corticosterone (CORT), in four reptile species for which blood was taken within a range of times 11 min or less after first disturbance. Changes in CORT were observed in cottonmouths (Agkistrodon piscivorus; 4 min after first disturbance), rattlesnakes (Crotalus oreganus; 2 min 30 s), and rock iguanas (Cyclura cychlura; 2 min 44 s), but fence lizards (Sceloporus undulatus) did not exhibit a change within their 10-min sampling period. In both snake species, samples taken up to 3-7 min after CORT began to increase still had lower CORT concentrations than after exposure to a standard restraint stressor. The "3-min rule" appears broadly applicable as a guide for avoiding increases in plasma CORT due to handling and sampling in reptiles, but the time period in which to obtain true baseline CORT may need to be shorter in some species (rattlesnakes, rock iguanas), and may be unnecessarily limiting for others (cottonmouths, fence lizards).


Asunto(s)
Recolección de Muestras de Sangre/veterinaria , Corticosterona/sangre , Reptiles/sangre , Restricción Física/fisiología , Agkistrodon/sangre , Animales , Recolección de Muestras de Sangre/métodos , Recolección de Muestras de Sangre/psicología , Recolección de Muestras de Sangre/normas , Corticosterona/análisis , Crotalus/sangre , Técnicas de Diagnóstico Endocrino/normas , Técnicas de Diagnóstico Endocrino/veterinaria , Manejo Psicológico , Iguanas/sangre , Lagartos/sangre , Restricción Física/psicología , Estrés Psicológico/sangre , Estrés Psicológico/etiología , Factores de Tiempo
4.
Zoo Biol ; 39(6): 391-396, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32754909

RESUMEN

Zoos use ambassador animals in educational programs featuring close contact with humans. Chinchillas (Chinchilla lanigera) at the Saint Louis Zoo are retrieved for programs by a keeper wearing brown handling gloves, but green cleaning gloves are worn during normal husbandry when physical contact with the animal is only incidental. The chinchillas' primary keeper anecdotally reported more reactivity and movement from chinchillas when approached with handling gloves. Animals' behavioral reactions to the presence of humans often include locomotion and vigilance, but these responses may be attenuated by predictability. To investigate these behaviors, handling trials involving brief contact attempts with both cleaning and handling gloves were filmed. Results indicated that chinchillas responded to disturbances by moving, jumping, and adopting more alert body postures. Surprisingly, movement was recorded in longer durations when the keeper attempted to touch the animals with cleaning gloves. This higher arousal may indicate that the animal was not expecting to be handled, yet an attempt to do so was being made. This reaction provides evidence that potentially aversive events should be reliably and consistently signaled.


Asunto(s)
Crianza de Animales Domésticos , Animales de Zoológico , Conducta Animal , Chinchilla , Manejo Psicológico , Animales , Femenino , Humanos , Masculino
5.
Trop Anim Health Prod ; 52(2): 743-751, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31595384

RESUMEN

The objective of this study was to assess aspects of the social behavior of a mixed-breed herd of beef cows as a potential source for stress and economic losses. Angus (AN; N = 10), Brahman (BR; N = 10), and Senepol (SE; N = 10) cows were assigned to two groups (N = 15 each containing equal breed numbers) on separate pastures. Agonistic interactions (win/loss) during feeding were recorded daily for 45 days. Dominance values were estimated as the proportion of individuals dominated to total herdmates. From this, individuals were placed into social categories based upon linear ranking as follows: dominants (D), intermediate (I), and subordinates (S). Breed influenced (P < 0.01) social category, with SE cows being dominants (P < 0.05) over AN and BR cows. Interactions between AN and BR cows were less (P < 0.0005) than interactions between AN and SE (53 vs 140, respectively). Within breeds, BR (152) and SE (182) cows had more (P < 0.0005) agonistic interactions than AN (107) cows. Although apparently influenced by breed, agonistic interactions occurred more frequently (P < 0.005) between social categories than within social categories (814 vs 310, respectively). Dominant cows were involved in more agonistic interactions with cows from different social categories than were intermediate and subordinate cows (P < 0.0005). However, intermediate (100) and subordinate (157) cows generated more (P < 0.0005) agonistic interactions within their own social category than dominant cows (53). It was concluded that, in mixed-breed herds, breed influences both social organization and agonistic interactions which could be considered as potential sources of stress and economic losses.


Asunto(s)
Crianza de Animales Domésticos/métodos , Bovinos/fisiología , Manejo Psicológico , Conducta Social , Estrés Fisiológico/fisiología , Conducta Agonística , Crianza de Animales Domésticos/economía , Animales , Cruzamiento , Bovinos/clasificación , Bovinos/genética , Dominación-Subordinación , Femenino
6.
Gen Comp Endocrinol ; 272: 1-8, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30419229

RESUMEN

Handling of avian study species is common in ecological research, yet few studies account for the impact of handling in nestlings where exposure to stress may result in negative lifetime fitness consequences. As a result, our understanding of stress reactivity in free-living avian young is limited. In this study we examined the cumulative impact of three levels of research-relevant handling (control, daily and every three days) on the development of the stress response, growth and condition of semi-precocial seabird chicks from near-hatching to near-fledging. By measuring corticosterone concentrations in plasma, we found that mottled petrel (Pterodroma inexpectata) chicks were capable of mounting a stress response comparable to adults from near-hatching. There were no differences in plasma corticosterone concentrations in initial samples (<4 min) between groups at six weeks of age, though by 12 weeks of age plasma corticosterone concentrations in initial samples collected from chicks handled daily were lower than chicks that were handled once every three days, and from control chicks. Corticosterone responses to handling were lower in chicks handled daily at six and 12 weeks of age when compared to other handling groups. Handling chicks daily or every three days had no negative effect on the growth or condition of chicks when compared to control chicks. These findings indicate that daily handling results in chicks became accustomed to handling, with no evidence that regular handling was detrimental to mottled petrel chicks. However, given the unique life-history characteristics of mottled petrels relative to closely related species, we caution that this finding may be species-specific, and wider testing is recommended.


Asunto(s)
Corticosterona/sangre , Estrés Fisiológico/fisiología , Animales , Pollos , Femenino , Manejo Psicológico
7.
J Dairy Sci ; 102(11): 10369-10378, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31495614

RESUMEN

Cattle lameness is an important welfare concern that also has an economic impact on the dairy industry. It can be a significant problem among pasture-based herds. Our objectives were to identify cow- and herd-level factors related to lameness and hoof lesions in dairy cows grazing year-round in Minas Gerais, Brazil. We performed a cross-sectional study in 48 pasture-based dairy herds, visiting each farm in a single visit. We evaluated 2,262 cows for mobility score (0-3) and 392 cows for hoof lesions. We used a questionnaire and checklist to capture herd management data. All information obtained was used to build multivariable models. The factors associated with lameness were low body condition score, longer time spent in the corral, being kept in paddocks during the drought period, and poor hygiene. For hoof lesions, track features were the most significant factor in determining the likelihood of heel horn erosion, white line fissure, and sole hemorrhage-by more than 3 times. Different factors related to unhygienic conditions such as leg cleanliness, frequency of cleaning, and longer time spent in the corral were associated with infectious hoof lesions. Poor human-animal relationship was related to sole hemorrhage, but patient handling of cows on the track was a protective factor against interdigital hyperplasia. The results of this study suggest that improving hygiene conditions, track features, and cow handling can improve dairy cattle mobility scores in pasture-based farms under tropical conditions. These findings also represent a first step toward planning actions aimed at decreasing lameness and hoof lesions in the studied region.


Asunto(s)
Enfermedades de los Bovinos/etiología , Industria Lechera/métodos , Pezuñas y Garras/patología , Cojera Animal/etiología , Crianza de Animales Domésticos/métodos , Crianza de Animales Domésticos/normas , Animales , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Lista de Verificación , Estudios Transversales , Ambiente , Granjas/clasificación , Granjas/estadística & datos numéricos , Femenino , Marcha , Manejo Psicológico , Higiene , Cojera Animal/epidemiología , Modelos Logísticos , Registros/veterinaria , Factores de Riesgo , Encuestas y Cuestionarios , Clima Tropical
8.
J Avian Med Surg ; 33(1): 38-45, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31124610

RESUMEN

Avian patients are presented commonly to veterinarians for preventive and disease-induced care. Physical examinations commonly are used to assess the overall patient, but this requires manual restraint, which often leads to increased stress and subsequent deleterious effects. To develop a noninvasive evaluation of the stress response in cockatiels (Nymphicus hollandicus), we evaluated the behavior of 26 juvenile cockatiels during their normal daily routine and after an acute stressful event (manual restraint and physical examination). Nonstressed behavior budgets were established by performing quantitative ethograms using 10-minute focal animal sampling methods with point samples recorded every 5 seconds. The ethograms then were repeated after a >10-minute restraint period for physical examination and venipuncture. Plasma corticosterone levels at baseline (<3 minutes) and after stress (>10 minutes) were compared to accompanying behaviors. Plasma corticosterone levels significantly increased after restraint. Overall, reactionary behaviors and inactivity increased, while locomotion, feeding, interaction with the environment, and displays of aggression decreased in the stressed birds. Maintenance behaviors were not significantly different before and after restraint, but the subjective character changed, with stressed birds displaying an increase in behaviors that were short in duration with minimal decrease in vigilance. Our results will be helpful to develop a method of quantifying stress in companion avian patients by using behavioral indicators. However, further study into specific behaviors of significance is needed.


Asunto(s)
Cacatúas/fisiología , Manejo Psicológico , Restricción Física/veterinaria , Estrés Fisiológico/fisiología , Estrés Psicológico , Animales , Corticosterona/sangre , Femenino , Masculino , Distribución Aleatoria , Restricción Física/fisiología , Restricción Física/psicología , Estrés Psicológico/etiología , Estrés Psicológico/fisiopatología , Grabación en Video
9.
Pharmacol Res ; 128: 179-189, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28970177

RESUMEN

Variations in the early postnatal environment of rodents produce long-term changes in responses to stress that may underlie neuropsychiatric diseases such as anxiety, depression and schizophrenia. GABAA receptors undergo marked changes in their subunit composition during this period, involving a regionally-dependent replacement of α2 with α1 subunits, the so-called α-subunit switch. In this study we examined the effects of early-life environment on adulthood GABAA receptor α1 and α2 subunit expression and the synaptic clustering of GABAA receptors. Male and female mice were exposed to either 15min daily handling sessions (EH) or no intervention (NH) over postnatal day (PND) 1-14. Adulthood behavioural differences in anxiety were assessed on the elevated plus-maze. Immunoperoxidase histochemistry was used to examine the density of the α1 and α2 subunit proteins. Double-labelling immunofluorescence and confocal microscopy were used to study GABAA receptor synaptic clustering. NH animals showed increased anxiety-type behaviours in the elevated plus maze relative to EH mice. NH males showed a loss of α2 subunits from the thalamus and lower layers of the somatosensory cortex, whilst NH females showed a reduction of α2 but increase in α1 protein in lower layers of the primary somatosensory cortex only. The NH condition also reduced α1 subunit expression in dentate gyrus (DG) in both males and females. Regardless of sex, NH mice showed reduced colocalisation of GABAA receptor α2 subunits with the synaptic marker gephyrin relative to the control condition. These findings suggest that early-life environment has long-lasting effects on GABAA receptors, leading to long-term changes in adulthood behaviour, and are of relevance to neurodevelopmental explanations of stress-augmented neuropsychiatric disorders.


Asunto(s)
Ansiedad/fisiopatología , Conducta Animal/fisiología , Subunidades de Proteína/fisiología , Receptores de GABA-A/fisiología , Animales , Encéfalo/fisiología , Proteínas Portadoras/fisiología , Femenino , Manejo Psicológico , Masculino , Proteínas de la Membrana/fisiología , Ratones
10.
Proc Natl Acad Sci U S A ; 112(45): 13811-6, 2015 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-26504228

RESUMEN

Nonhuman primates use social touch for maintenance and reinforcement of social structures, yet the role of social touch in human bonding in different reproductive, affiliative, and kinship-based relationships remains unresolved. Here we reveal quantified, relationship-specific maps of bodily regions where social touch is allowed in a large cross-cultural dataset (N = 1,368 from Finland, France, Italy, Russia, and the United Kingdom). Participants were shown front and back silhouettes of human bodies with a word denoting one member of their social network. They were asked to color, on separate trials, the bodily regions where each individual in their social network would be allowed to touch them. Across all tested cultures, the total bodily area where touching was allowed was linearly dependent (mean r(2) = 0.54) on the emotional bond with the toucher, but independent of when that person was last encountered. Close acquaintances and family members were touched for more reasons than less familiar individuals. The bodily area others are allowed to touch thus represented, in a parametric fashion, the strength of the relationship-specific emotional bond. We propose that the spatial patterns of human social touch reflect an important mechanism supporting the maintenance of social bonds.


Asunto(s)
Manejo Psicológico , Relaciones Interpersonales , Apego a Objetos , Tacto , Adulto , Puntos Anatómicos de Referencia , Europa (Continente) , Femenino , Humanos , Masculino , Análisis de Regresión , Autoinforme
11.
Dev Psychobiol ; 60(4): 458-467, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29521416

RESUMEN

Play is an important part of normal childhood development and seen in many mammals, including rats. To better understand the interplay between genotype and postnatal experiences, the effects of neonatal handling on play were assessed in Lewis (LEW) and Fischer 344 (F344) rats. Handled litters experienced brief periods of separation during the first two postnatal weeks. F344 rats were less likely to direct nape contacts toward an untreated Sprague-Dawley (SD) partner and less likely to rotate to a supine position in response to a nape contact. When compared to rats from control litters, handled LEW, and F344 rats were more likely to respond to nape contacts with complete rotations, suggesting that handling increased playful responsiveness to a comparable extent in both strains. SD rats paired with handled inbred rats had more nape contacts than those paired with non-handled rats. While handled LEW rats also tended to direct more nape contacts to the SD partner than non-handled LEW rats there was no difference between handled and non-handled F344 rats. These results could not be readily explained by handling-induced changes in either maternal care or anxiety. These data suggest that the behavioral consequences of neonatal handling may not depend to a great extent on the genetic platform that these manipulations are acting on. These data also suggest that the ability to maintain the ebb and flow between playful solicitation and playful responsiveness may be compromised in F344 rats and may contribute to the lower levels of play in this strain.


Asunto(s)
Ansiedad/fisiopatología , Conducta Animal/fisiología , Manejo Psicológico , Ratas Endogámicas F344/fisiología , Ratas Endogámicas Lew/fisiología , Animales , Animales Recién Nacidos , Femenino , Masculino , Embarazo , Ratas , Ratas Sprague-Dawley
12.
Learn Mem ; 24(9): 449-461, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28814471

RESUMEN

Emotional states influence how stimuli are interpreted. High anxiety states in humans lead to more negative, threatening interpretations of novel information, typically accompanied by activation of the amygdala. We developed a handling protocol that induces long-lasting high and low anxiety-like states in rats to explore the role of state anxiety on brain activation during exposure to a novel environment and fear conditioning. In situ hybridization of the inducible transcription factor Egr-1 found increased gene expression in the lateral nucleus of the amygdala (LA) following exposure to a novel environment and contextual fear conditioning in high anxiety-like rats. In contrast, low state anxiety-like rats did not generate Egr-1 increases in LA when placed in a novel chamber. Egr-1 expression was also examined in the dorsal hippocampus and prefrontal cortex. In CA1 of the hippocampus and medial prefrontal cortex (mPFC), Egr-1 expression increased in response to novel context exposure and fear conditioning, independent of state anxiety level. Furthermore, in mPFC, Egr-1 in low anxiety-like rats was increased more with fear conditioning than novel exposure. The current series of experiments show that brain areas involved in fear and anxiety-like states do not respond uniformly to novelty during high and low states of anxiety.


Asunto(s)
Ansiedad/metabolismo , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Conducta Exploratoria/fisiología , Miedo/psicología , Regulación de la Expresión Génica/fisiología , Animales , Encéfalo/metabolismo , Condicionamiento Clásico/fisiología , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Manejo Psicológico , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley
13.
Hippocampus ; 27(2): 210-220, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27874237

RESUMEN

Recent studies have shown that tactile stimulation (TS) in pups is able to prevent and/or minimize fear, anxiety behaviors, and addiction to psychostimulant drugs in adult rats. In these studies, animals have been exposed to handling from postnatal day (PND) 1-21. This study was designed to precisely establish which period of preweaning development has a greater influence of TS on neuronal development. After birth, male pups were exposed to TS from PND1-7, PND8-14, and PND15-21. In adulthood, the different periods of postnatal TS were assessed through behavioral, biochemical, and molecular assessments. Animals that received TS from PND8-14 showed lower anxiety-like symptoms, as observed by decreased anxiety index in elevated plus maze. This same TS period was able to improve rats' working memory by increasing the percentage of alternation rate in Y-maze, and induce better ability to cope with stressful situations, as showed in the defensive burying test by a reduced time of burying behavior. On the other hand, animals receiving TS in the first week of life showed longest cumulative burying time, which is directly related to increased anxiety-like behavior. Moreover, TS from PND8-14 showed lower corticosterone levels and better oxidative status, as observed by decreased lipid peroxidation and increased catalase activity in the hippocampus. Brain-derived neurotrophic factor (BDNF) immunocontent was increased in the hippocampus of animals receiving TS from PND8-14, while glucocorticoid receptors immunocontent was decreased in both TS1-7 and TS15-21 , but not TS8-14 . To the best of our knowledge, this study is the first to show TS can be more efficient if applied over a focused period of neonatal development (PND8-14) and this beneficial influence can be reflected on reduced emotionality and increased ability to address stressful situations in adulthood. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Manejo Psicológico , Hipocampo/crecimiento & desarrollo , Hipocampo/metabolismo , Receptores de Glucocorticoides/metabolismo , Tacto , Adaptación Psicológica/fisiología , Animales , Animales Recién Nacidos , Ansiedad/metabolismo , Catalasa/metabolismo , Corticosterona/sangre , Conducta Exploratoria/fisiología , Peroxidación de Lípido/fisiología , Masculino , Aprendizaje por Laberinto/fisiología , Memoria a Corto Plazo/fisiología , Actividad Motora/fisiología , Estimulación Física , Distribución Aleatoria , Ratas Wistar , Método Simple Ciego
14.
Neurobiol Learn Mem ; 144: 27-35, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28579367

RESUMEN

In rodents, fragmented and low levels of maternal care have been implicated in age-related cognitive decline and the incidence and progression of Alzheimer's pathology. In contrast, enhancing early postnatal maternal care has been associated with improved cognitive function later in life. Here we examined whether early postnatal handling of mouse pups from postnatal days 2-9 enhanced maternal care and whether this affected cognition and Alzheimer pathology at 5 and 11months of age in the APPswe/PS1dE9 mouse model for Alzheimer's disease. Brief, 15min daily episodes of separating offspring from their dams from postnatal days 2-9 (early handling, EH) increased maternal care of the dam towards her pups upon reunion. At 11 (but not 5) months of age, EH APPswe/PS1dE1 mice displayed significantly reduced amyloid plaque pathology in the hippocampus. At this age, EH also prevented short-term working memory deficits while restoring impairments in contextual fear memory formation in APPswe/PS1dE9 mice. EH did not modulate amyloid pathology in the amygdala, nor did it affect auditory fear conditioning deficits in APPswe/PS1dE9 mice. We conclude that increased levels of maternal care during the early life period delays amyloid accumulation and cognitive decline in an Alzheimer's mouse model, involving the hippocampus, but not to the amygdala. These studies highlight the importance of the early postnatal period in modulating resilience to develop Alzheimer's pathology later in life.


Asunto(s)
Enfermedad de Alzheimer/patología , Disfunción Cognitiva , Manejo Psicológico , Hipocampo/patología , Conducta Materna , Placa Amiloide/patología , Enfermedad de Alzheimer/complicaciones , Animales , Condicionamiento Clásico , Miedo , Femenino , Masculino , Memoria a Corto Plazo , Ratones Transgénicos , Placa Amiloide/complicaciones
15.
Epilepsia ; 58(12): e162-e166, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29105060

RESUMEN

The endocannabinoid system has gained attention as an important modulator of activity in the central nervous system. Initial studies focused on cannabinoid receptor 1 (CB1), which is widely expressed in the brain, but recent work also implicates cannabinoid receptor 2 (CB2) in modulating neuronal activity. Both receptors are capable of reducing neuronal activity, generating interest in cannabinoid receptor agonists as potential anticonvulsants. CB1 (Cnr1) and CB2 (Cnr2) single-knockout mice have been generated, with the former showing heightened seizure sensitivity, but not overt seizures. Given overlapping and complementary functions of CB1 and CB2 receptors, we queried whether double-knockout mice would show an exacerbated neurological phenotype. Strikingly, 30% of double-knockout mice exhibited provoked behavioral seizures, and 80% were found to be epileptic following 24/7 video-electroencephalographic monitoring. Single-knockout animals did not exhibit seizures. These findings highlight the importance of the endocannabinoid system for maintaining network stability.


Asunto(s)
Epilepsia/genética , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB2/genética , Animales , Conducta Animal , Electroencefalografía , Epilepsia/etiología , Manejo Psicológico , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Red Nerviosa/fisiopatología , Fenotipo , Convulsiones/etiología , Convulsiones/genética , Convulsiones/psicología
16.
Anim Cogn ; 19(1): 171-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26395986

RESUMEN

Fear reactions in horses are a major cause of horse-human accidents, and identification of effective pathways for reduction in fearfulness can help decreasing the frequency of accidents. For a young mammal, the mother is one of the most salient aspects of its environment, and she can have a strong influence on her offspring's behaviour. This study investigated whether fearfulness in foals can be reduced through weekly exposure to usually frightening objects with a habituated mother during the first 8 weeks of life. Prior to foaling, mares (N = 22) were habituated to five initially fear-eliciting situations, including exposure to novel stationary and moving objects. At birth, the foals were randomly assigned to either a Demonstration group (N = 11) or a Control group (N = 11). Demonstration mares demonstrated habituation towards the objects to their foals once per week in weeks 1-8 post-partum. Control mares were inside the empty test arena with their foals for the same amount of time. The foals were tested at 8 weeks and 5 months of age in four standardised fear tests. Demonstration foals showed significantly reduced fear responses (behaviour and heart rate) and increased exploratory behaviour at both 8 weeks and 5 months of age. The effect was likely achieved through a combination of maternal transmission and individual learning. It is concluded that fearfulness in foals may be reduced through exposure to frightening objects together with their habituated mother during the first 8 weeks of life.


Asunto(s)
Conducta Animal/fisiología , Miedo/psicología , Caballos/psicología , Madres , Animales , Animales Lactantes/psicología , Femenino , Manejo Psicológico , Frecuencia Cardíaca/fisiología , Masculino , Distribución Aleatoria
17.
Neurourol Urodyn ; 35(2): 192-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25394276

RESUMEN

AIMS: Mice are increasingly being used as models to investigate aspects of urinary dysfunction that humans with lower urinary tract symptoms (LUTS) experience. One method used to examine voiding function is the spontaneous void spot assay. The purpose of this study was to characterize and identify animal husbandry conditions that might confound results of the spontaneous void spot assay in male C57Bl/6J mice. METHODS: Mice were placed in cages lined with filter paper for 4 hr and urine was visualized with UV transillumination. Voiding parameters including urine spot number, spot size, total urine area, primary void area, corner and center voiding were quantified. RESULTS: Adult male mice void more frequently with advancing age and a subpopulation (5-10%) display a frequent spotting pattern at 6-9 weeks of age. Voiding was not significantly different in male mice weaned to group housing (4-6 per cage) versus single housing, and was not altered when they were used as breeders. Voiding was changed upon transferring group housed adult males to single density cages, which decreased total urine area. Repeated assays of male voiding behavior over three consecutive days increased primary void area by the third day of monitoring and revealed that voiding behavior is impacted by routine cage changes and time of day. CONCLUSIONS: Together these results identify housing and husbandry practices that influence male voiding behaviors in the spontaneous void spot assay and will inform voiding behavior analyses conducted with male C57Bl/6J mice.


Asunto(s)
Crianza de Animales Domésticos/métodos , Técnicas de Diagnóstico Urológico , Vivienda para Animales , Micción , Urodinámica , Factores de Edad , Animales , Conducta Animal , Ritmo Circadiano , Manejo Psicológico , Masculino , Ratones Endogámicos C57BL , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Factores de Tiempo
18.
Gen Comp Endocrinol ; 233: 109-114, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27222349

RESUMEN

Glucocorticoids can play a critical role in modulating life-history trade-offs. However, studying the effects of glucocorticoids on life-history often requires experimentally elevating plasma glucocorticoid concentrations for several weeks within normal physiological limits and without repeated handling of the animal. Recently, implants made of beeswax and testosterone (T) were shown to have release dynamics superior to some currently available T implants, and these beeswax implants dissolved, eliminating the need to recapture the animal. We evaluated the utility of beeswax implants containing four different dosages of corticosterone (CORT; the primary glucocorticoid in birds) and their effect on several condition indices in a captive colony of zebra finches (Taeniopygia guttata). The three implants with the greatest CORT doses (0.05, 0.1, and 0.5mg) produced spikes in plasma CORT concentrations 20h after treatment, but were within the limits that zebra finches may normally experience. The 0.5mg CORT implant elevated plasma CORT between typical baseline and restraint stress levels reported in other studies of zebra finches for the entire 35day experiment. Birds in the 0.5mg implant group were heavier, had greater furcular fat scores, and had lower hematocrit than birds in the control and other CORT implant groups. Beeswax CORT implants are a low cost method of elevating plasma CORT for a prolonged time. Furthermore, because there is no need to remove these implants at the end of a study, this method may be amenable to studies of free-ranging animals.


Asunto(s)
Corticosterona/administración & dosificación , Corticosterona/sangre , Implantes de Medicamentos/química , Pinzones , Ceras/química , Animales , Peso Corporal/efectos de los fármacos , Pinzones/sangre , Pinzones/fisiología , Glucocorticoides/sangre , Manejo Psicológico , Hematócrito , Testosterona/sangre
19.
J Dairy Sci ; 99(3): 2131-2141, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26778308

RESUMEN

Cattle handling is a dangerous activity on dairy farms, and cows are a major cause of injuries to livestock handlers. Even if dairy cows are generally tranquil and docile, when situations occur that they perceive or remember as aversive, they may become agitated and hazardous to handle. This study aimed to compare human-animal interactions, cow behavior, and handler safety when moving cows to daily milking and moving cows to more rarely occurring and possibly aversive hoof trimming. These processes were observed on 12 Swedish commercial dairy farms. The study included behavioral observations of handler and cows and cow heart rate recordings, as well as recording frequencies of situations and incidents related to an increased injury risk to the handler. At milking, cows were quite easily moved using few interactions. As expected, the cows showed no behavioral signs of stress, fear, or resistance and their heart rate only rose slightly from the baseline (i.e., the average heart rate during an undisturbed period before handling). Moving cows to hoof trimming involved more forceful and gentle interactions compared with moving cows to milking. Furthermore, the cows showed much higher frequencies of behaviors indicative of aversion and fear (e.g., freezing, balking, and resistance), as well as a higher increase in heart rate. The risk of injury to which handlers were exposed also increased when moving cows to hoof trimming rather than to routine milking. Some interactions (such as forceful tactile interactions with an object and pulling a neck strap or halter) appeared to be related to potentially dangerous incidents where the handler was being kicked, head-butted, or run over by a cow. In conclusion, moving cows to hoof trimming resulted in higher frequencies of behaviors indicating fear, more forceful interactions, and increased injury risks to the handler than moving cows to milking. Improving potentially stressful handling procedures (e.g., by better animal handling practices and preparation of cows to cope with such procedures) can increase handler safety, animal welfare, ease of handling, and efficiency.


Asunto(s)
Crianza de Animales Domésticos/métodos , Industria Lechera/métodos , Manejo Psicológico , Estrés Fisiológico , Bienestar del Animal , Animales , Conducta Animal , Bovinos , Frecuencia Cardíaca/fisiología , Pezuñas y Garras , Humanos , Lactancia , Leche/metabolismo , Suecia
20.
Dev Psychobiol ; 58(5): 614-22, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27020142

RESUMEN

Neonatal handling is an experimental procedure used to analyze the effects of environmental interventions during early postpartum days (PPD). Long-lasting effects of repeated stress exposure in the neonatal period on the maternal side are poorly studied in this model. The aim of this study was to verify if handling the pups induces enduring effects on damsstress responses, increasing their risk for depression. Dams were divided into two groups (NH-Non-handled and H-Handled) based on the handling procedure (pups were handled for 1 min/per day from PPD1-PPD10) and then subdivided into four groups (NH, NH + S, H, and H + S) based on the exposure or not to restraint stress after weaning (1 hr/per day for 7 days, PPD22-PPD28). We analyzed damsbehavior in the forced swimming test (FST PPD29-PPD30), plasma basal corticosterone and BDNF levels, as well as adrenal weight (PPD31). The results show that handling alters the stress response of dams to acute and chronic stress, as evidenced by dams of the H group having increased immobility in the first day of FST (p < .001), similar to NH + S (p < .01). Dams of the H and H + S groups show decreased levels of corticosterone when compared to NH and NH + S groups (p < .05), but the H + S group shows an increased adrenal weight, suggesting an increased sensibility of the maternal organism to the chronic stress applied after weaning (p < .05). We show that handling may induce a long-lasting effect on maternal stress response; these changes in the damsemotional reactivity increase their susceptibility for the development of psychiatric disorders such as depression. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58: 614-622, 2016.


Asunto(s)
Conducta Animal/fisiología , Factor Neurotrófico Derivado del Encéfalo/sangre , Corticosterona/sangre , Depresión , Estrés Psicológico , Glándulas Suprarrenales/anatomía & histología , Animales , Animales Recién Nacidos , Depresión/sangre , Depresión/etiología , Depresión/fisiopatología , Emociones/fisiología , Femenino , Manejo Psicológico , Masculino , Ratas Wistar , Estrés Psicológico/sangre , Estrés Psicológico/etiología , Estrés Psicológico/fisiopatología
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