RESUMEN
OBJECTIVES: Type A aortic dissection with true lumen collapse and malperfusion downstream is associated with a devastating prognosis. This study compares the clinical outcomes of two operative strategies for this disease: hybrid approach of ascending aorta (and hemiarch replacement) supplemented with retrograde stenting of the descending aorta (thoracic endovascular aortic repair [TEVAR]) and standard ascending aorta (and hemiarch) replacement without stent placement. METHODS: From January 1, 2016 to December 31, 2019, 81 patients with type A aortic dissection were studied. The hybrid technique was applied in 30 patients (group 1), while 51 patients received standard surgical repair (group 2). Patient demographics, clinical and operative findings, postoperative outcome, follow-up interventions, and mid-term survival were analyzed. RESULTS: Baseline characteristics were similar among the groups, except that more preoperative malperfusion was evident in group 1. The postoperative incidence of visceral malperfusion (0 vs. 15.7%, p = 0.02) and low cardiac output syndrome requiring extracorporeal membrane oxygenation support (3.3 vs. 19.6%, p = 0.04) was significantly less in group 1. In-hospital mortality was also significantly lower in group 1 as in group 2 (13.3 vs. 33.3%, p = 0.04). At follow-up, the need for secondary endovascular stenting (3.3 vs. 7.8%, p = 0.65) and surgical aortic reintervention (6.7 vs. 2.0%, p = 0.55) was comparable. One-year, 2-year, and 3-year survival rates were 83.3, 83.3, and 62.5% in group 1, and 58.7, 58.7, and 52.6% in group 2 (p = 0.05), respectively. CONCLUSION: The combination of open surgical replacement of the ascending aorta (and hemiarch) with TEVAR of the descending aorta for true lumen compromise is a feasible treatment option for patients with type A aortic dissection and is associated with a better perioperative outcome and improved mid-term survival rate.
Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Resultado del Tratamiento , Stents , Estudios Retrospectivos , Complicaciones Posoperatorias/cirugíaRESUMEN
Electroejaculation (EE) is stressful and probably painful; thus the administration of anaesthesia is recommended to decrease those negative effects. However, anaesthesia has a direct risk of provoking death, but sedation is less risky than anaesthesia. At the same time, α2-adrenergic agonists may improve semen quality. Therefore, the aim of the present study was to compare the physiological and behavioural responses indicative of stress and possibly pain, and the semen quality in electroejaculated untreated, anaesthetised or sedated goat bucks. Semen was collected from eight bucks using three different procedures in all them (EE in untreated bucks, EE under sedation or EE under general anaesthesia). The number of vocalizations during EE and the behavioural pattern before and after procedures were recorded. Pain visual analogue scale (VAS) score was also determined during EE. Rectal temperature, heart rate, serum cortisol concentration, biochemical and haematological parameters were measured before and after each procedure, and sperm characteristics were determined. Bucks vocalised more often when untreated than sedated or anaesthetised (P<0.02). The pain VAS score was greater when bucks were untreated than sedated or anaesthetised (P<0.002). The rectal temperature, heart rate, total protein, albumin and haemoglobin concentrations were greater when bucks were untreated than anaesthetised or sedated (P<0.02). Serum cortisol increased after EE (P=0.0006), without differences between procedures. The frequency and duration of lying down after EE were greater when bucks were anaesthetised than sedated or untreated (P<0.05), and were also greater when bucks were sedated than untreated (P<0.05). The number of times that the animal tried to stand up after EE was greater when bucks were anaesthetised than sedated or untreated (P<0.02). The sperm mass motility was greater when bucks were anaesthetised or sedated than when they were untreated (P=0.048). When animals were sedated, the ejaculate contained more spermatozoa with functional plasma membrane (P=0.03) and morphologically normal (P=0.05) than when they were untreated. In conclusion, general anaesthesia and sedation decreased the stress and probably the pain response provoked by EE and especially sedation improved the quality of the semen collected.
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Bienestar del Animal , Cabras/fisiología , Semen/fisiología , Anestesia/veterinaria , Animales , Conducta Animal , Eyaculación , Hidrocortisona/sangre , Masculino , Análisis de Semen/veterinaria , Motilidad Espermática , Espermatozoides/fisiología , Estrés FisiológicoRESUMEN
The objectives of this study were to determine (i) if in subtropical goats that gave birth during mid-December, the exposition to an artificial long-day photoperiod consisting in only 14 hr of light per day can increase the milk yield and (ii) to test whether these females can respond to the male effect at the end of the prolonged photoperiodic treatment. In experiment 1, 17 lactating goats were maintained under natural short days (control group), while another 22 goats were maintained under artificial long days (treated group) consisting in 14 hr light and 10 hr darkness starting at day 10 of lactation. The continuous exposition to an artificial long-day photoperiod produced an increase in the milk yield level during the first 110 days of lactation (time × treatment interaction; p = .01), while none of the milk components were modified due to the photoperiodic treatment (p > .05). In experiment 2, all control and treated anovulatory goats were submitted to the male effect using photostimulated males. All females showed oestrous behaviour within the first 10 days that were in contact with males (100% in both groups; p > .05). Thus, the latency to onset of oestrus did not differ between females from control (58.2 ± 3.0 hr) and treated (62 ± 4.6 hr) groups. Male exposition provoked ovulation independently if females were previously under long days or natural photoperiod (96 vs 100%, respectively; p = .79). It was concluded that exposure to 14 hr of light per day in subtropical goats that gave birth in late autumn stimulates milk yield without preventing the ovulation in response to the male effect at the end of the prolonged photoperiodic treatment.
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Cabras/fisiología , Lactancia/fisiología , Ovulación/fisiología , Animales , Composición Corporal , Clima , Estro/fisiología , Femenino , Masculino , Fotoperiodo , Conducta Sexual Animal/fisiología , Factores de TiempoRESUMEN
INTRODUCTION: The perineal adhesive bag is the most used method in our country for urine culture collection in infants, despite having a high risk of contamination and false-positive results. We aim to quantify both types of risks through a systematic review. METHODS: Search updated in May 2014 in PUBMED, SCOPUS (includes EMBASE), IBECS; CINAHL, LILACS AND CUIDEN, without language or time limits. Percentages of contaminated urines, false positives, sensitivity and specificity (with respect to catheterization or bladder puncture) were recorded. RESULTS: A total of 21 studies of medium quality (7,659 samples) were selected. The pooled percentage of contaminated urines was 46.6% (15 studies; 6856 samples; 95% confidence interval [95% CI]: 35.6 to 57.8%; I(2): 97.3%). The pooled percentage of false positives was 61.1% (12 studies; 575 samples; 95% CI: 37.9 to 82.2%; I(2): 96.2%). Sensitivity (88%; 95% CI: 81-93%; I(2): 55.2%), and specificity (82%; 95% CI: 75-89%; I(2): 41.3%) were estimated in five studies, but without including contaminated urines. CONCLUSION: The perineal adhesive bag is not a valid enough method for urine culture collection, because almost half are contaminated and, if they are positive, two out of three are false. Although these estimates are imprecise, because of their great heterogeneity, they should be considered when choosing the method of urine collection. The estimates of sensitivity and specificity are not applicable because they do not take into account the risk of contamination.
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Urinálisis , Toma de Muestras de Orina/instrumentación , Contaminación de Equipos , Humanos , Lactante , Sensibilidad y Especificidad , Infecciones Urinarias/diagnósticoRESUMEN
Plasma cortisol and behavior were measured in disbudded goat kids with and without the use of cornual nerve block. A total of 45 kids were used in 5 experimental groups (n=9, males and females). Group LidoD was infiltrated with 1 mL of 2% lidocaine locally at the cornual branches of lacrimal and infratrochlear nerves, 15 min before thermal disbudding. Group Lido was similarly infiltrated and was not disbudded. In group Sim, the disbudding procedure was simulated. A control group (CD) was disbudded without lidocaine infiltration, and group SD was infiltrated with saline before disbudding. The cornual nerve block did not prevent the short-term increase in cortisol levels during and after disbudding. LidoD, CD and SD groups showed higher cortisol concentrations than Lido and Sim (p<0.05) during the first 20 min after the procedure. Frequency of vocalizations during the procedure was significantly different between groups and was higher in SD (29.6 ± 3.1; mean±SE) and CD (28.4 ± 3.1) than in Sim (16.6 ± 3.1; p<0.05). Infiltrating lidocaine did not decrease this response to disbudding (21.1 ± 3.1; p>0.05). Struggles tended to be higher in SD (16.5 ± 2.5), CD (17.8 ± 2.5) and LidoD (15.6 ± 2.5) than Sim (10.6 ± 2.5; p=0.1). The total behavioral response was different between groups (CD, 59.6 ± 6.8; LidoD, 52 ± 6.8; SD, 62.6 ± 6.8; Sim, 36.8 ± 6.8; p=0.05), and disbudded animals showed the strongest reactions (disbudded, 58.1 ± 3.9 vs non-disbudded, 36.8 ± 6.8; p=0.01). It was concluded that cornual nerve block (lacrimal and infratrochlear) using 2% lidocaine did not prevent pain during thermal disbudding of goat kids.
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Anestésicos Locales/uso terapéutico , Cabras/fisiología , Cuernos/cirugía , Lidocaína/uso terapéutico , Bloqueo Nervioso/métodos , Dolor/fisiopatología , Animales , Femenino , Hidrocortisona/sangre , Masculino , Actividad Motora/efectos de los fármacos , Dolor/tratamiento farmacológico , Distribución Aleatoria , Cola (estructura animal) , Grabación en Video , Vocalización Animal/efectos de los fármacosRESUMEN
The objectives were to investigate if partial substitution of a grazing diet with a supplemental high-starch feed during the last 12 d of gestation improved colostrum yield and neonatal activity in goat does grazing semi-arid rangeland. For the first objective, 25 pregnant does were randomly assigned to 1 of 2 treatments: 1) grazing only (control; n = 11), and 2) grazing plus 0.6 kg/d of supplemental corn (as fed), a high starch feed, during the last 12 ± 1.0 d before parturition (SC; n = 14). Colostrum was collected at parturition and again at 1, 3, 6, and 10 h postpartum for yield and composition. In all goats, blood concentrations of glucose and plasma progesterone were determined. Total colostrum yield/10 h was greater (P = 0.002) in the SC does (1,102 ± 144 g) than in control does (405 ± 50 g). From 6 to 10 h postpartum, contents of colostrum protein and solids not fat were less (P ≤ 0.012) whereas lactose contents were greater (P = 0.035) in the SC does than in control does. Concentration of glucose in the blood at parturition was greater (P = 0.037) in the SC does (160 ± 13 mg/dL) than in control does (115 ± 12 mg/dL). A significant decrease (P = 0.001) in plasma progesterone concentrations occurred 1 d before parturition in control does, whereas the decrease (P = 0.008) occurred 3 d before parturition in SC does. For the second objective, 20 does (10 per group) and their single kids were randomly assigned to the same treatments as above for evaluation of dietary treatment on neonatal activity. Kid activity was assessed using videos recorded during the first 90 min after birth. Frequency of low-pitched bleats was greater (P < 0.001) in kids of SC does than in kids of controls. Frequencies and durations of teat seeking from 30 to 90 min after birth and of suckling activity were greater (P ≤ 0.015) in kids of SC does than in kids of controls. Duration of parturition was longer (P = 0.001) in control does (58 ± 10.2 min) than in SC does (21 ± 2.8 min). Finally, percentage of fetal malpresentation was greater (P = 0.036) in control does (33.3%) than in SC does (9.0%). We conclude that partial substitution of the grazing diet with a high-starch feed, corn, during the last 12 d of gestation improved colostrum yield and neonatal activity in goats grazing subtropical semi-arid rangeland.
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Alimentación Animal/análisis , Animales Recién Nacidos/fisiología , Calostro/fisiología , Cabras/fisiología , Fenómenos Fisiologicos Nutricionales Maternos , Zea mays , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Peso Corporal , Dieta/veterinaria , Femenino , Parto , EmbarazoRESUMEN
We investigated whether undernutrition during the second half of pregnancy impaired the behaviour of does and their kids at parturition and early mutual recognition. Twenty-two control and 22 underfed mixed-breed, multiparous dairy goats were used, together with their respective kids (control, n = 31: nine singles, 16 twins and six triplets; underfed, n = 32: 11 singles, 18 twins and three triplets). Undernutrition involved limiting protein and energy intake at 70% of the nutritional requirements for maintenance and foetal growth from day 70 of pregnancy until birth. The behaviour of mothers and their two first-born kids was observed for 90 min from the birth of each kid. Maternal olfactory recognition of the kid was assessed at 4 h post partum by testing selective nursing behaviour. Non-olfactory recognition was assessed at 8 h in a two-choice test excluding olfactory cues. In kids, preference for the mother was assessed in a two-choice test at either 12 or 24 h post partum. Bodyweight of does and kids were lower in the underfed group up to 2 weeks post partum. At parturition, licking, maternal bleating frequency and latency to nursing did not differ between nutritional groups. Control kids were faster than underfed kids to stand, search for and reach the udder, but underfed kids bleated more and tended to spend more time at the udder. Both control and underfed does accepted their own kid and rejected the alien in the selectivity test at 4 h. In contrast, at 8 h post partum, only control goats showed a significant preference for their own kid in the non-olfactory recognition test. Both control and underfed kids showed a preference for their own mother at 12 and 24 h and undernutrition during pregnancy had little influence on the performance of kids. However, 12 h-old underfed kids tended to be less active than control kids and visited their own mothers less than control kids. There were no significant correlations between the behaviour of the mother or of the kid at parturition and their performance in the discrimination tests. Overall, undernutrition in the second half of pregnancy appears to be more detrimental for the behaviour of the mother than for the kid. Furthermore, it has more impact on the establishment of maternal non-olfactory recognition than on maternal care at parturition or the establishment of maternal selectivity.
RESUMEN
The northern aplomado falcon (Falco femoralis septentrionalis) disappeared from south Texas in the 1940s. Due to great success in the release of captive-reared aplomado falcons in south Texas, there are currently more than 40 established nesting pairs in the region. Addled eggs from aplomado falcons nesting in northern Chihuahua and south Texas were analyzed to determine organochlorine (OC) and inorganic element contaminant burdens and their potential association with egg failures and effects on reproduction. Among the OCs, DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] was present at the highest concentrations (range 262-21487 ng/g wet weight) followed by polychlorinated biphenyls (PCBs, range 88-3274 ng/g ww). DDE was greater (P=0.03) in eggs from El Sueco (Chihuahua, Mexico) than in those from Matagorda Island (Texas, USA). DDE concentrations in eggs of aplomado falcons from El Sueco were elevated; however, reproductive success in the two Chihuahuan populations did not seem to be affected by DDE. DDE and metals in potential avian prey of the aplomado falcon from Matagorda Island were very low and below levels in the diet at which some negative effects might be expected. Except for mercury (Hg), metal concentrations in eggs were fairly low and were not different among locations in Chihuahua and south Texas. Hg was somewhat elevated and was greater (P<0.001) in Texas than in the Chihuahua locations. Periodic monitoring of Hg concentrations in addled eggs of aplomado falcons in south Texas is recommended to continue evaluating potential negative effects on their recovery.
Asunto(s)
Huevos , Contaminantes Ambientales/análisis , Falconiformes , Animales , Geografía , Hidrocarburos Clorados/análisis , Metales Pesados/análisis , México , TexasRESUMEN
We investigated whether kids were able to discriminate their own mother from an alien one in a two-choice test on the day of birth when they had access to acoustic, visual and olfactory cues from their mother, and whether this discrimination depended on the selective maternal behaviour of the mother (i.e. exclusive nursing of own kids). When given the choice between their own mother and an alien equivalent dam, 8-h-old kids did not show a significant preference for their dam, whereas 12- and 24-h-old kids did. When given the choice between their own and an alien mother that were both non-selective because they had been rendered peripherally anosmic by irrigation of the nostrils with zinc sulphate, 12-h-old kids did not show a significant preference for their mother. These results are similar to those reported in sheep and may suggest that the contrast of behaviour between their own and an alien mother existing in normosmic does is important for discrimination of dams by kids at this age. Finally, testing 8-h-old kids in a smaller enclosure resulted in some improvement of their performance, although they still failed to display a significant preference for their mother. On the whole, kids are able to discriminate between their own and an alien mother goat as early as previously reported in lambs. The impairment of this ability when mothers are anosmic and not selective suggests that acceptance behaviours displayed by the mother may serve as one of the cues orientating the choice of the kid when given the choice between intact mothers. Finally, the present results do not suggest the existence of fundamental differences in the establishment of a preference for the mother between lambs, which are followers, and kids, which are hiders.
RESUMEN
Opuntia soehrensii (Osp) planta empleada por la medicina tradicional andina, ha mostrado en estudios previos tener actividad protectora de la infección causada por el virus Herpes simplex. En este trabajo se definieron las condiciones y el mecanismo por los que se evidencia este efecto. Osp mostro actividad de protección antiviral óptima a 48 horas de exposición.
Asunto(s)
Etnobotánica/métodos , Etnofarmacología/métodos , Medicina TradicionalRESUMEN
La hepatitis A es una enfermedad inflamatoria necrosante de tipo agudo, que se presenta como consecuencia de una infección por este virus. El presente estudio evaluó la incidencia y prevalencia de esta patología mediante la detección de marcadores serológicos específicos por medio del Ensayo Inmunoenzimático (EIA), en una población con diagnóstico clínico de hepatitis viral aguda.
Asunto(s)
Humanos , Virus de Hepatitis , Hepatitis A/diagnósticoRESUMEN
Los virus Herpes simplex pueden causar infecciones que requieren tratamiento a lo largo de la vida. Pueden causar infecciones severas del sistema nervioso central que pueden agravarse en individuos inmunocomprometidos y recién nacidos. Estudios de prevalencia de esta infección y su importancia en nuestro medio aun no han sido encarados, probablemente por el costo de los reactivos. El presente trabajo reporta la obtención y evaluación de un sustrato antigénico, obtenido a partir de cepas nativas de herpes simplex en línea celular BHK-21, para detectar anticuerpos antivirales específicos en muestras séricas. El sustrato fue evaluado por el ensayo de Inmunofluorescencia indirecta, los resultados fueron considerados empleando parámetros biológicos y estadísticos de validación en comparación con el ensayo Inmunoensimático del 77 por ciento, especificidad de 75 por ciento, capacidad prara predecir resultados positivos del 83 por ciento y de resultados negativos del 75 por ciento; además de buena reproducibilidad y respetibilidad del ensayo. La validación del ensayo permitirá contar con una técnica alternativa y de bajo costo que facilite el acceso al diagnóstico y el estudio de la prevalencia de infección por este virus en muestro medio.
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Técnicas de Cultivo de Célula , Técnica del Anticuerpo Fluorescente Indirecta , Simplexvirus , Alergia e InmunologíaRESUMEN
En la pasada década la amplificación de secuencias nucleicas fue dearrollada como una herramienta de investigación. En la actualidad estos procedimientos son reportados en la detección y monitoreo de varias patologías, entre ellas las enfermedades causadas por virus. La presente revisión, examina la aplicación de estas técnicas en el diagnóstico de las enfermedades virales, asimismo discute sus ventajas y limitaciones en coparación con procedimientos convencionales.
Asunto(s)
Enterovirus , Hepatitis , Herpes Zóster , Control de Infecciones , Reacción en Cadena de la Polimerasa , Virus Sincitiales Respiratorios , Infecciones por Adenovirus Humanos , Gripe Humana , Infecciones por ParamyxoviridaeRESUMEN
El diagnóstico de infecciones respiratorias virales en nuestro medio es básicamente clínico debido al acceso limitado y relativa complejidad de los procedimientos de diagnóstico virológico. El presente trabajo reporta el diagnóstico de infección por VRS en tres pacientes menores a 2 años de edad con diagnóstico inicial de infección respiratoria aguda y fracaso terapéutico al uso de antibióticos de amplio espectro. El diagnóstico fue realizado mediante aislamiento y cultivo del virus en sistemas de cultivo celular ja vitre, a partir de secreciones nasofaringeas. El aislamiento de VRS fue confirmado por detección de antígenos virales por inmunofluorescencia directa, utilizando anticuerpos monoclonales anti-VRS. Este tipo de procedimientos nos permitirá profundizar en el estudio de enfermedades respiratorias causadas por VRS, su adecuado diagnóstico y la adopción de un tratamiento apropiado y oportuno para el niño
Asunto(s)
Humanos , Masculino , Femenino , Virus Sincitiales Respiratorios , Infecciones del Sistema Respiratorio , Infecciones por Virus Sincitial Respiratorio , Infecciones del Sistema RespiratorioRESUMEN
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.
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Discriminación en Psicología/fisiología , Individualidad , Aprendizaje/fisiología , Conducta Materna/fisiología , Ovinos/psicología , Animales , Animales Recién Nacidos , Femenino , Trastornos del Olfato/inducido químicamente , Vocalización Animal/fisiologíaRESUMEN
La heterogénea respuesta clínica a la infección por HSV, tanto en pacientes inmunocomprometidos como en huéspedes inmunocompetentes, plantea el uso de ensayos de laboratorio de modo óptimo para el diagnóstico apropiado y control oportuno de esta enfermedad. Para esto, en la práctica se cuenta con ensayos inmunoenzimáticos, moleculares y de aislamiento viral. siendo este último el ensayo de referencia para un diagnóstico definitivo. El virus del herpes replica fácilmente in vitro en varios cultivos celulares estandard (células de riñón de cobayo, de pulmón de visón, de riñón de mono, y fibroblastos humanos) y, en 1 a 4 días se pueden observar efectos citopáticos característicos. El presente trabajo reporta la replicación activa y eficiente del HSV en lineas celulares HeLa y BHK-21 (Células de carcinoma cervical humano y células de riñón de hamster sirio, respectivamente). Inicialmente, se evaluó la biología de las líneas celulares bajo las condiciones de laboratorio (tiempo de duplicación celular, poblacional,etc). Ls datos obtenidos fueron la base para diseñar el protocolo de aislamiento viral. La susceptibilidad celular a la infección viral fue examinada utilizando muestras de herpes ocular. Las condiciones de muestreo y de transporte fueron optimizadas. El proceso de infección fué facilitado por un periodo de absorción y centrifugación inicial. La infección activa se evidenció a las 17 horas mediante observación de efectos citopáticos y a las 48 horas por determinación de antígenos virales por Inmunofluorescencia Indirecta. El ensayo podría determinar una infección activa por Herpes en corto periodo de tiempo, contribuyendo así a la identificación de este virus como agente causal de la enfermedad
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Humanos , Masculino , Femenino , Herpes Simple , Virus , Quimioterapia del Cáncer por Perfusión Regional , Control de InfeccionesAsunto(s)
Dolor Abdominal/etiología , Anorexia/etiología , Trastornos de Deglución/etiología , Intestinos/anomalías , Preescolar , Diafragma , Femenino , Humanos , Hígado , SíndromeRESUMEN
Ewes identify their young through the use of different sensory modalities. Olfactory recognition, which mediates selective acceptance at the udder, is established at 4 h postpartum (pp). Visual and auditory cues are involved in recognition at a distance, which is evident at 12 h pp. This study investigates whether anosmic ewes are able (a) to develop visual and auditory recognition and (b) to restore selective acceptance of their lamb at the udder. Visual and auditory recognition was assessed in anosmic and intact ewes at 12 h and 24 h pp by a test of two choices: their own and an alien lamb. Selectivity at allowing suckling was tested by presenting successively an alien and the familiar lamb at 4 h, 3 days, and 1 month pp. In the two-choice recognition test, at both 12 h and 24 h pp, anosmic as well as intact ewes showed a preference for their familiar lamb. Although anosmic ewes showed no difference in their acceptance of alien and familiar lambs for suckling at 4 h and 3 days pp, they nursed the alien lamb less at 1 month pp and showed more rejection behaviors toward it. Thus, visual, auditory, or both those types of recognition can be rapidly established, independent of olfactory recognition. Moreover, differential behavior of anosmic ewes toward their own versus an alien lamb at the udder at 1 month suggests that vision and audition may compensate to some extent for the loss of olfaction.
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Señales (Psicología) , Aprendizaje Discriminativo/fisiología , Lactancia/fisiología , Memoria/fisiología , Ovinos/fisiología , Olfato/fisiología , Estimulación Acústica , Animales , Animales Recién Nacidos , Animales Lactantes , Conducta Animal/fisiología , Femenino , Trastornos del Olfato/inducido químicamente , Estimulación Luminosa , Periodo Posparto , Tiempo de Reacción/fisiología , Sulfato de ZincRESUMEN
Two studies were carried out to test the ability of Préalpes du Sud x Lacaune (Study 1) and Rambouillet ewes (Study 2) to recognize their lambs during the first 24 h postpartum. Ewes were given the choice between their own and an alien lamb of approximately the same age, in a triangular pen of 10 m×10 m×10 m. A lamb was placed in each of the two corners while the mother was released from the third corner. Direct access to the lambs was prevented by an open barrier located at 1 m from the pens in which the lambs were kept. Ewes were studied at 8 h (n=10, 12), 12 h (n=20, 10) and 24 h postpartum (n=29, 9; Study 1 and Study 2 respectively). Tests lasted 3 and 5 min in Study 1 and 2, respectively. Although the first choice of the ewes did not differ from random, in both studies mothers spent significantly more time near their own lamb than near the alien. In both breeds a significant preference for the own lamb was already present at 8 h (P<0.05). We conclude that ewes are very likely to recognize their lamb without the aid of olfactory cues as early as 8 h postpartum, which is much sooner than thought from previous studies.