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Scent Marking Around the Breeding Season in Two Newly Formed Mexican Grey Wolf (Canis lupus baileyi) Pairs Kept in Captivity
I. Escobar-Ibarra,L. Mayagoitia,C. Gonzalez-Rebeles,R. Ramirez-Necoechea
International Journal of Zoological Research , 2006,
Abstract: The aim of the study was to analyse the scent marking patterns in frequency, type and position throughout the reproductive period of two pairs of Canis lupus baileyi housed in two zoos (LZ = Leon and ZZ = Zacango), in terms of newly and established pairs. Focal behaviour sampling was used to register 1,211 scent markings. Data were grouped in three periods: before, during, after and posterior to the reproductive season. Between newly formed pairs no significant difference was found in the previous period (U = 6.50, p>0.065); also, no significant difference was observed in the double marking (U = 54.0, p>0.083) during the reproductive season, although it was greater in the LZ compared to the ZZ pair. After commingling together for one year the established LZ couple, showed an increase in double marking (U = 16.5, p<0.001) during the mating period in comparison with the prior year. Male wolves marked with greater frequency with the leg raised in both, the double and single marking, whereas females marked more in a squatting position. It is concluded that scent marking is different in recently formed pairs in captivity, which are found in a reduced space and have not free choice to elect its mate.
Case Report of Malignant Mammary Neoplasia in Mexican Gray Wolf (Canis lupus baileyi)
Rosales Alferez Federico,F. Tavares Mendoza Hector,E. Pereda Solis Martin,H. Martinez Guerrero Jose,M. Herrera Casio Hector
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2010.1472.1475
Abstract: We report the presence, excision and diagnosis of malignant mammary neoplasia from a 14 years old female Mexican gray wolf (Canis lupus baileyi). Through auscultation we observed and palpated three neoplasia in the mammary gland. We also noted anorexia, lethargy in the animal with rigidity and lameness in the posterior end of the body. We surgically removed the tumors and took samples for histopathological studies which revealed a mixed mammary tumor composed of infiltrating ductal carcinoma with centers of mucinous, epidermoid and chondrosarcoma (chondrosarcoma carcinoma).
Model Sensitivity and Use of the Comparative Finite Element Method in Mammalian Jaw Mechanics: Mandible Performance in the Gray Wolf  [PDF]
Zhijie Jack Tseng,Jill L. Mcnitt-Gray,Henryk Flashner,Xiaoming Wang,Reyes Enciso
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0019171
Abstract: Finite Element Analysis (FEA) is a powerful tool gaining use in studies of biological form and function. This method is particularly conducive to studies of extinct and fossilized organisms, as models can be assigned properties that approximate living tissues. In disciplines where model validation is difficult or impossible, the choice of model parameters and their effects on the results become increasingly important, especially in comparing outputs to infer function. To evaluate the extent to which performance measures are affected by initial model input, we tested the sensitivity of bite force, strain energy, and stress to changes in seven parameters that are required in testing craniodental function with FEA. Simulations were performed on FE models of a Gray Wolf (Canis lupus) mandible. Results showed that unilateral bite force outputs are least affected by the relative ratios of the balancing and working muscles, but only ratios above 0.5 provided balancing-working side joint reaction force relationships that are consistent with experimental data. The constraints modeled at the bite point had the greatest effect on bite force output, but the most appropriate constraint may depend on the study question. Strain energy is least affected by variation in bite point constraint, but larger variations in strain energy values are observed in models with different number of tetrahedral elements, masticatory muscle ratios and muscle subgroups present, and number of material properties. These findings indicate that performance measures are differentially affected by variation in initial model parameters. In the absence of validated input values, FE models can nevertheless provide robust comparisons if these parameters are standardized within a given study to minimize variation that arise during the model-building process. Sensitivity tests incorporated into the study design not only aid in the interpretation of simulation results, but can also provide additional insights on form and function.
Bucking the Trend in Wolf-Dog Hybridization: First Evidence from Europe of Hybridization between Female Dogs and Male Wolves  [PDF]
Maris Hindrikson, Peep M?nnil, Janis Ozolins, Andrzej Krzywinski, Urmas Saarma
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046465
Abstract: Studies on hybridization have proved critical for understanding key evolutionary processes such as speciation and adaptation. However, from the perspective of conservation, hybridization poses a concern, as it can threaten the integrity and fitness of many wild species, including canids. As a result of habitat fragmentation and extensive hunting pressure, gray wolf (Canis lupus) populations have declined dramatically in Europe and elsewhere during recent centuries. Small and fragmented populations have persisted, but often only in the presence of large numbers of dogs, which increase the potential for hybridization and introgression to deleteriously affect wolf populations. Here, we demonstrate hybridization between wolf and dog populations in Estonia and Latvia, and the role of both genders in the hybridization process, using combined analysis of maternal, paternal and biparental genetic markers. Eight animals exhibiting unusual external characteristics for wolves - six from Estonia and two from Latvia - proved to be wolf-dog hybrids. However, one of the hybridization events was extraordinary. Previous field observations and genetic studies have indicated that mating between wolves and dogs is sexually asymmetrical, occurring predominantly between female wolves and male dogs. While this was also the case among the Estonian hybrids, our data revealed the existence of dog mitochondrial genomes in the Latvian hybrids and, together with Y chromosome and autosomal microsatellite data, thus provided the first evidence from Europe of mating between male wolves and female dogs. We discuss patterns of sexual asymmetry in wolf-dog hybridization.
Integration of Two Newly Formed Couples of Canis lupus baileyi at Two Zoos in Mexico  [PDF]
Isabel Escobar-Ibarra,Lilian Mayagoitia,Ramiro Ramirez-Necoechea,Daniel Mota-Rojas
International Journal of Zoological Research , 2009,
Abstract: The study was done to determine when social integration occurs in newly formed Mexican gray wolf couples. Two wolf pairs, at Zacango Zoo (ZZ) and Leon Zoo (LZ) respectively, were observed daily from the time they were put together until 15 days after the breeding season was over. Social behavior frequencies were split out in five periods: Anterior, Previous, During, After and Posterior to the breeding season. The Binomial test was used to analyze the social interactions between the pairs and the differences between genders. During the reproductive season both couples showed a significative increase in neutral behaviors-mainly by the females, all disappearing in the After period. In both groups, males were on the defensive and playful behavior, aggressive behavior was displayed almost exclusively by the bitches. Again, this last behaviour decreased in the After-breeding period. In conclusion, neither playful nor aggressive behavior observed indicate that wolves had socially integrated, since as in neutral interactions, these behaviors were only shown During the reproductive season and then disappeared afterwards.
A non-invasive, improved RIA and overt observation in the study of singleton Apennines’ wolf (Canis lupus) reproductive behavior  [PDF]
Chiara Profico,Roberto Trentini,Nicola Bernabò,Nadia Govoni
Animal Biology & Animal Husbandry , 2010,
Abstract: The analysis of fecal hormones allows a close but non-invasive monitoring of animals avoidingthe stress of restraint/capture, which in turn can upset animals’ hormonal profile. Steroid hormoneprogesterone was analysed in three singleton, female grey wolves of different age, belonging to theendangered species of the Apennines’ Canis lupus. The analysis was carried out during the breedingseason by using an improved radioimmunoassay on samples collected on the field. To reduce the stressto animals and danger to people, the overt observations were carried out by operators who were alreadyfamiliar with the animals, saving the money of a camera-monitoring-system. Concurrently, a male and afemale gray wolves housed together were monitored as a control. The results indicated the importance ofdehydration of fecal samples before the extraction with petroleum ether, which was shown to be moreefficient than diethyl ether, and that pre-treatment with methanol greatly enhances extraction (p<0.01).Females of Apennines’ grey wolf showed the first sign of oestrus by a vaginal blood loss, that was easilydetected on the ground; the analysis carried out on fecal samples revealed a rapidly declining lutealphase, with P4 metabolites reaching the basal values of a non-cyclic female. In the matter of welfare,behavioural observations on Apennines’ grey wolf showed that unpaired animals, although familiar withthe operators, failed to display a sexual social behavior during the reproductive season, that is thebehavioural signs were hidden in overt observational situation.
PRESENCE OF BROOD PATCH IN FORPUS XANTHOPS KEPT IN CAPTIVITY  [PDF]
Cesar Ortiz Z
The Biologist (Lima) , 2012,
Abstract: We report the presence of the brood patch in females of Forpus xanthops (yellow-faced parrotlet) kept in captivity.
A note on reproduction of Didelphis marsupialis in captivity
Motta, Maria de Fatima Dezonne;Carreira, Jo?o Carlos de Araujo;Franco, Antonia Maria Ramos;
Memórias do Instituto Oswaldo Cruz , 1983, DOI: 10.1590/S0074-02761983000400016
Abstract: conditions leading to successful reproduction of didelphis marsupialis in captivity are described. a trial involving four mating pairs which had been maintained at least four months in the laboratory resulted in three litters and one false pregnancy. this is, to our knowledge, the first record of successful breeding of this species in captivity.
Environmental enrichment for neotropical primates in captivity
Boere, Vanner;
Ciência Rural , 2001, DOI: 10.1590/S0103-84782001000300031
Abstract: captivity is an extreme non-natural environment for primates. the success of a breeding colony depends of management and veterinarian procedures which must rely on the knowledge of primates' behavioral needs. environmental enrichment consists of a series of procedures that improve the quality of life of captive animals by meeting their ethological needs. enrichment can reduce stress, while increasing animal well being in captivity. suitable ethical conditions, incidences of behavioral disorders, minimal clinical interventions, low mortality, higher reproduction rates and cost/benefit relationship, reflect directly on the quality of captive breeding colonies. anthropoids like neotropical primates possess complex neural structures and relate, in a sophisticated manner, to the environment. this review reports important experiences on enrichment procedures for neotropical primates and the physiological events which could explain improvement of animal well-being.
Environmental enrichment for neotropical primates in captivity  [cached]
Boere Vanner
Ciência Rural , 2001,
Abstract: Captivity is an extreme non-natural environment for primates. The success of a breeding colony depends of management and veterinarian procedures which must rely on the knowledge of primates' behavioral needs. Environmental enrichment consists of a series of procedures that improve the quality of life of captive animals by meeting their ethological needs. Enrichment can reduce stress, while increasing animal well being in captivity. Suitable ethical conditions, incidences of behavioral disorders, minimal clinical interventions, low mortality, higher reproduction rates and cost/benefit relationship, reflect directly on the quality of captive breeding colonies. Anthropoids like Neotropical primates possess complex neural structures and relate, in a sophisticated manner, to the environment. This review reports important experiences on enrichment procedures for Neotropical primates and the physiological events which could explain improvement of animal well-being.
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