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1.
Primates ; 65(5): 411-419, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39068634

RESUMEN

Activity budget analyses are important for understanding how animals spend their time in daily activities like resting, foraging, moving and socializing. These behaviors are closely linked to energy management, so habitat quality and resource availability are known to influence the activity budgets of species. Therefore, many studies have examined the consequences of habitat loss and fragmentation on the energetic demands and activity budgets of species. However, we still have limited knowledge of how animals behave in large, continuous, and protected environments, as such habitats are currently rare. The present study analyzed how temporal variation, age, sex and reproductive status influenced the activity budget of wild red howler monkeys (Alouatta guariba clamitans), in one of the last Atlantic Forest remnants that remains large and protected. Between November 2017 and December 2018, we monitored two groups, G3 and G4, in Parque Estadual Carlos Botelho, São Paulo, Brazil. The groups were composed of one adult male, two adult females and their offspring and one (G3) or two (G4) subadult males, using scan sampling for behavioral for data collection every 20 min. The most common behavior was resting, followed by foraging, moving and social interactions, with inter-group differences. Temporal variation explained most of the fluctuations in the activity budget, so did age and sex, but to a lesser degree. The reproductive status of females did not alter their activity budget. These findings reveal that even neighboring groups display distinct and intricate relationships with their habitat. Future studies should be conducted in continuous forests to determine what is the expected range of variation in activity budget, particularly in those species considered as flexible and inhabiting endangered habitats, such as the Atlantic Forest.


Asunto(s)
Alouatta , Bosques , Reproducción , Animales , Alouatta/fisiología , Femenino , Masculino , Brasil , Ecosistema , Factores de Edad , Factores Sexuales , Conducta Social , Conducta Animal
2.
Theriogenology ; 118: 150-156, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29906665

RESUMEN

Two experiments were performed to evaluate the reproductive performance of zebu beef cows treated with different doses of eCG at the end of a progesterone (P4)/estrogen based protocol for timed artificial insemination (TAI). In Experiment 1, suckling Bos indicus Nelore cows (n = 261) received, on day 0, a progesterone (P4) intravaginal device (PD) and an injection of 1 mg estradiol benzoate (EB). On day 8, the PD was removed, 500 µg of cloprostenol was injected, and cows were assigned to one of the following groups: Control (no treatment), 300 (300 IU of eCG), 600 (600 IU of eCG), and 900 (900 IU of eCG). On day 9, all cows received 1 mg EB and TAI performed 54-56 h after cloprostenol injection. A pregnancy diagnosis was done by ultrasound scanning 40 days after TAI, and the number of fetuses and calves was recorded at pregnancy diagnosis and at birth. More cows treated with eCG displayed estrus within 48 h after removal of the PD (42.3% vs. 11.6%, P < 0.01), and ovulated more than one follicle (42%, 58/138 vs. 1.8%, 1/54; P < 0.01). This effect on ovulation rate was dose dependent (P < 0.05). The pregnancy rate was affected only by cow parity (primiparous, 25.3% vs. multiparous, 48.9%; P < 0.01). Twin pregnancy was higher (P < 0.01) in cows treated with eCG (42%, 58/138) than controls (0%, 0/54). However, few cows (33.3%) were able to keep both fetuses intact until birth. For evaluation of ovarian characteristics by B-mode and Doppler ultrasonography, 43 Nelore cows were submitted In Experiment 2 to the same four groups described in Experiment 1. Although no difference (P > 0.1) was observed for size and blood perfusion in the pre-ovulatory follicles, corpus luteum was larger and with greater blood perfusion (P < 0.05) in eCG-treated cows. In conclusion, eCG increased the number of double/multiple ovulations in a dose-dependent manner, induced larger and more vascularized corpora lutea, but did not affect the fertility of cyclic or anestrous cows. Although eCG results in twin pregnancies, most of cows underwet embryo/fetus loss and birth a single calf.


Asunto(s)
Bovinos/fisiología , Estradiol/administración & dosificación , Gonadotropinas Equinas/administración & dosificación , Inseminación Artificial/veterinaria , Progesterona/administración & dosificación , Reproducción/efectos de los fármacos , Animales , Gonadotropina Coriónica/administración & dosificación , Cuerpo Lúteo/anatomía & histología , Cuerpo Lúteo/irrigación sanguínea , Cuerpo Lúteo/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Estro/efectos de los fármacos , Estro/fisiología , Femenino , Fertilidad/efectos de los fármacos , Humanos , Inseminación Artificial/métodos , Ovulación/efectos de los fármacos , Embarazo , Índice de Embarazo , Embarazo Gemelar/estadística & datos numéricos , Factores de Tiempo
3.
J Med Primatol ; 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29693261

RESUMEN

BACKGROUND: The advent of non-invasive methods provides a powerful alternative to stress studies as the use of stressful handling techniques is no longer needed. However, many factors influence hormone metabolism such as sex, diet, and metabolic rate. Thus, validation should be species- and matrix-specific. METHODS: To assess stress response in brown howler monkeys Alouatta clamitans, we adopted an ACTH challenge test and parallelism to provide physiological and laboratorial validation. Radioimmunoassay was used to measure fecal levels of corticosterone. RESULTS AND CONCLUSIONS: All challenged animals presented a peak in fecal glucocorticoids levels the day after the treatment, while control animals did not. There were no significant sex differences, but females with infants had higher levels of corticosterone. Corticosterone levels showed parallelism to the standard curve of the diagnostics kit. Collectively, the data suggest that the method was validated and is useful for monitoring stress, thereby helping in conservation programs both in captivity and in the wild. Transit time information may be coupled with travel distance in seed dispersal studies.

4.
Folia Primatol (Basel) ; 74(1): 54-6, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12606852

RESUMEN

The study of the reproductive strategy developed by different species in order to adapt to their environmental conditions and their meaning in an evolutionary perspective is essential for understanding the mechanisms involved in the process of reproduction. Non-human primates are very interesting models for this purpose. Some species show a typical seasonal reproductive pattern, such as rhesus macaques (Macaca mulatta) [Sade, 1964; Conaway and Sade, 1965] and ring-tailed lemurs (Lemur catta) [Zuckerman, 1953], while others, such as gorillas (Gorilla gorilla) and chimpanzees (Pan troglodytes) [Puschmann, 1975], show relative independence of the environment. Neotropical primates display many different breeding strategies. Female capuchin monkeys (Cebus apella), for instance, having reached puberty, have fertile cycles year-round [Hamlett, 1939; Nagle and Denari, 1983]. Interestingly, there are reports of a clear peak of births in free-living [Hamlett, 1939] and captive colonies [Welker et al., 1983] in the dry season, i.e. May-June in the southern hemisphere. Some authors suggest that a seasonal variation in spermatogenesis could explain the birth peak [Freese and Oppenheimer, 1981]. The aim of this study was to investigate this theory, measuring seasonal variation in total testicular volume in a captive group of male capuchin monkeys and assessing its temporal correlation with the birth season as an indirect indication of variation in male fertility.


Asunto(s)
Cebus/fisiología , Estaciones del Año , Testículo/crecimiento & desarrollo , Animales , Peso Corporal , Fertilidad , Masculino , Testículo/fisiología
5.
Braz. j. vet. res. anim. sci ; 35(4): 195-197, 1998.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1470551

RESUMEN

Aiming at the evaluation of the occurrence of thyroxine and progesterone-17-alpha-OH circadian rhythm, 4 adult crossbred swine females (non-pregnant and showing no estrous signs) were studied, reared and kept under a industrial management system. Hormone determinations were assessed by solid phase radioimmunoassay (RIA)ª. Thyroxine serum analysis showed the highest concentrations around 3:00 PM and decreased until reaching the lowest values at the 0:00 to 4:00 AM interval. Regarding progesterone-17-alpha-OH, the highest concentrations were observed at 3:00 AM, showing a progressive decrease along the day until reaching lower values at the 12:00 to 3:00 PM interval.


No presente trabalho foram utilizadas quatro fêmeas suínas, adultas, mestiças, não-gestantes e sem sinais clínicos de estro, criadas e mantidas sob condições industriais de criação. Objetivou-se avaliar a ocorrência de ritmicidade biológica circadiana para tiroxina e 17-alfa -OH progesterona. Os ensaios para dosagens hormonais foram executados utilizando-se a técnica de radioimunoensaio (RIE) em fase sólida e para isso foi empregado conjunto de reagentes comerciais (COAT-A-COUNT R). As análises séricas de tiroxina mostraram valores mais elevados ao redor das 15 horas, decrescendo a partir dai até atingir níveis menores no intervalo da zero às 4 horas. Quanto a 17-alfa -OH progesterona, observaram-se níveis mais elevados por volta das 3 horas, decrescendo gradativamente ao longo do dia, até atingir menor concentração no intervalo das 12 às 15 horas.

6.
Braz. j. vet. res. anim. sci ; 35(5): 205-209, 1998.
Artículo en Portugués | LILACS-Express | LILACS, VETINDEX | ID: biblio-1470552

RESUMEN

In the present study 21 young female swines, sexually mature, reared and kept under a industrial management system were assessed for their progesterone serum profiles during the oestrus cycle. Blood sampling was performed always at the same interval, from 8:00 to 10:00 AM. Each animal was submitted to 14 venal punctions at days 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 21, 22 and 23 of the oestrous cycle. the first day of the oestrous phase was assumed to be Day 0 and the 23rd as the first of the next cycle. Hormone determinations were performed employing a solid phase radioimmunoassay (RIA). For progesterone 17-alpha-OH hormone, the observed mean values ranged from 0.18 to 2.7 ng/ml and for the androstenedione hormone those values ranged from 0.08 to 0.24 ng/ml.


No presente trabalho, foram utilizadas 21 fêmeas suínas, virgens, sexualmente aptas, criadas e mantidas sob condições industriais, para observação dos perfis hormonais séricos de 17-alfa-OH progesterona e androstenediona, durante o ciclo estral. As colheitas de sangue foram efetuadas sempre no mesmo intervalo, entre 8 e 10 horas. Cada animal foi submetido a 14 punções venosas, distribuídas nos dias zero, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 21, 22 e 23 do ciclo estral. Considerou-se o dia zero como o primeiro dia da fase estral, e o 23º dia como o primeiro do estro subseqüente. Os ensaios para dosagens hormonais foram executados utilizando-se a técnica de radioimunoensaio (RIE) em fase sólida e para isso foi empregado conjunto de reagentes comerciais (Coat-A-Count®). Para o hormônio 17-alfa-OH progesterona, foram encontrados valores médios que variaram entre 0,18 e 2,7 ng/ml e para o hormônio androstenediona esses valores oscilaram entre 0,08 e 0,24 ng/ml.

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