In seasonal mammals the duration of nocturnal melatonin secretion accurately reflects the environmental photoperiod. The endocrine rhythm is decoded by a specialised portion of the pituitary gland (the pars tuberalis, PT) which then relays this information to the pars distalis and hypothalamus, precipitating huge annual changes in physiology and behaviour. However how the PT decodes the melatonin signal is currently unknown. Melatonin influences gene transcription in the ovine PT at its onset and offset, and the phase relationship of these two groups is believed to form the underlying mechanism by which the PT integrates seasonal time. The transcripts induced at melatonin offset are understood to be under the control of a seasonally gated cAMP mechanism. Conversely processes involved in melatonin-mediated gene induction are currently not understood.The work in this thesis ultimately aims to reveal how the seasonal melatonin signal is decoded by the PT. To this end melatonin-mediated gene induction has been characterised through RNAseq, the highly displaced cohorts submitted to bioinformatic promoter analysis and the paradigm tested though in vitro modelling techniques.In this study a 1.5 h infusion with melatonin acutely regulated 219 transcripts in the ovine PT (115 induced, 104 repressed, >1.5 fold change), confirming previous association of several genes (including Cry1, MT1, Gadd45g, Nampt and Npas4) to rapid melatonin control. Gross promoter analysis of these groups indicated that the induced gene cohort was significantly enriched for GC content and CpG islands suggesting the involvement of epigenetic mechanisms of transcriptional control. Further bioinformatic analysis specifically implicated the importance of transcription factors ZFP161 and PAX5 in melatonin-mediated gene induction in the PT. Several immortalised cell lines were screened for the presence of a functional melatonin receptor. Two strains (MCF7 oMT1 and NES2Y) exhibited significant attenuation of forskolin-mediated cAMP accumulation when co-treated with melatonin, a hallmark of melatonin Gαi-coupled protein receptor signalling. These lines were subsequently evaluated as models of melatonin-mediated gene induction of the sheep PT through ovine promoter reporter assays of Cry1, Nampt, NeuroD1 and Npas4. However, treatment with melatonin failed to evoke a reporter response suggesting that the cell line models were inadequately equipped to reflect PT biology. Subsequently a protocol was established to culture ovine PT explants culture which faithfully recapitulated melatonin mediated transcriptional dynamics in vitro, providing a possible tool for the future investigation of the PT. Lastly, previous work has shown the transcriptional profile of Npas4 to peak highly and transiently, pre-empting the expression of other melatonin-induced genes. Using a COS7 cell line model, heterologously-expressed NPAS4 was shown to form functional heterodimeric partnerships with ARNT and ARNTL and transactivate both Cry1 and Nampt promoter reporters through novel binding sites. Collectively these data indicated NPAS4 to act as an immediate activator of melatonin regulated circuits

Memoria para optar al Título Profesional de Médico Veterinario / En el presente estudio se describe el desarrollo y validación de un Ensayo inmunoenzimático indirecto (ELISA-I) para el diagnóstico serológico de la infección por Brucella ovis (B. ovis) en ovinos, utilizando proteínas citosólicas de Brucella abortus RB51 (B. abortus RB51) como antígeno. Se probaron dos tipos de placas de poliestireno, NUNC 69620 y NUNC Maxisorp, dos tampones de sensibilización de diferente pH con dos alternativas de conjugado, el anticuerpo monoclonal anti IgG-caprino/ovino (Sigma A9452) y la proteína G (Sigma P81170). Las concentraciones óptimas de antígeno citosólico, sueros y conjugados fueron determinadas mediante titulación del tipo checkerboard. Para la validación del ensayo se utilizaron 55 sueros de ovinos considerados como infectados/expuestos, positivos a examen clínico, a un ELISA-I comercial, a la fijación del complemento (FC) y a la prueba de reacción en cadena de la polimerasa (PCR) y 338 sueros de ovinos no infectados, provenientes de un rebaño ovino libre de infección, negativos a la prueba de FC. El punto de corte diagnóstico fue determinado a través del método de las características del tipo receptor-operador (ROC). El ELISA-I desarrollado con anticuerpo monoclonal como conjugado mostró mejores valores de sensibilidad (90,9%) y especificidad (95,9%). Estos resultados, a pesar de ser significativos, son deficientes para ser considerados de utilidad diagnóstica y lograr un adecuado control de la infección en rebaños ovinos. La baja sensibilidad obtenida al utilizar proteínas citosólicas como antígeno estaría relacionada con la escasa exposición al antígeno y la corta memoria inmunológica que generarían este tipo de proteínas en un animal infectado.

Genome maps provide information used to identify economic trait loci and loci proximal to genes affecting economically important traits. This research contributes to the development of the ovine genome map by establishing ovine tissue culture techniques and fluorescent in situ hybridization techniques in this laboratory. In addition, a karyotype for sheep affected with spider lamb syndrome was developed. Ovine tissue culture techniques were established using fibroblasts grown from primary explants of sheep and modified cytogenetic procedures. Metaphase chromosomes were obtained from the fibroblast cultures and used for fluorescent in situ hybridization and for banding procedures to develop the spider lamb karyotype. Fluorescent in situ hybridization procedures were established by hybridizing a fluorescent-labeled probe to fixed ovine chromosome spreads. The probe was a bacterial artificial chromosome clone containing the bovine 3-β-hydroxy-5-ene steroid dehydrogenase gene. In this study, the probe hybridized to ovine chromosome 1. This chromosomal location was supported by the previous hybridization of the probe to bovine chromosome 3, which has a high level of homology with ovine chromosome 1. The final objective of this study was to determine whether a chromosomal abnormality is the cause of spider lamb syndrome, a fatal autosomal recessive genetic disease in North American black-faced breeds of sheep. A fibroblast cell line was produced from a four-week-old male homozygous spider lamb. Chromosomes were banded with trypsin using standard structural banding techniques. The lamb had a normal diploid chromosomes, 23 pairs of autosomal acrocentrics, and a large acrocentric X and a minute biarmed Y chromosome. G-band analysis of all chromosomes within the karyotype did not reveal any abnormality that was attributable to spider lamb syndrome.

This study was part of a program to develop new genotypes of sheep (Ovis spp.) and goats (Capra spp.) which are more useful for food and fiber production. The study examined the influence of domestication on behavioral and physiological traits of ewes and lambs, the influence of a single or twin offspring on ewe and lamb behaviors, and general relationships between ewes and lambs during the lambs' first month of life. Domestication has caused the intensities of observed traits to diverge greatly from the tendencies shown by wild populations. Domestication has produced increases in measurements associated with maternal care, discovery learning, tolerance or inclination for closeness with conspecifics, length of the breeding season, fertility, birth weight, and growth rate. Behaviors associated with imitative learning have decreased with domestication. Domestication has not altered the length of estrous cycle nor length of gestation. The partly domestic groups were intermediate to the most domestic and wild groups for three traits: maternal care, birth weight, and growth rate. However, other hybridization factors apparently altered the intermediate position of the partly domestic groups for the remaining traits: learning in the young, proximity of conspecifics, and fertility. The study's findings indicated that the development of new crossbreeds is an advantageous method of improving sheep and goat productivity. Some behavioral differences between ewes and their single lambs and ewes and their twin lambs resulted from the earlier physical development of singles as compared to twins: Singles played more and spent less time close to their mothers. Mothering capacities, sibling competition, and a sibling bond caused behavioral differences between ewes and their twin young and ewes and their single young: Twins suckled more, gained less weight, spent more time close to their mothers, stood more, received less sniffing from their mothers than did singles. The ewe-lamb bond did not vary between ewes and their single lambs and ewes and their twin lambs. The high occurrence of simultaneous behaviors and the maintenance of close contact between ewes and their offspring and between twins contributed to the cohesion and organization of the flock.

Face aux contraintes spatio-temporelles qu'ils peuvent rencontrer, les animaux doivent adopter des tactiques leur permettant d'assurer leur survie et leur reproduction. Nous avons cherché à identifier les tactiques d'utilisation des ressources et du temps ainsi que les facteurs de variation de cette utilisation dans deux populations de grands mammifères herbivores : le mouflon méditerranéen (Ovis gmelini musimon x Ovis sp.) et le chevreuil (Capreolus capreolus). Nous montrons que les mouflons sont particulièrement sensibles aux fortes chaleurs estivales et répondent en réduisant leur activité, notamment durant la période diurne. Concernant l'utilisation de l'habitat, les mouflons en activité utilisent davantage les habitats ouverts et moins les forêts de feuillus que les mouflons inactifs. Les données de localisation utilisées dans cette étude ont été obtenues à l'aide de colliers GPS dont le succès de localisation est influencé par le comportement de l'animal et les caractéristiques de l'habitat (végétation, topographie). Enfin, nous montrons que les femelles chevreuil modifient la taille de leur domaine vital en fonction principalement de la richesse du milieu, du nombre de faons, de leur âge et de la saison. Les résultats obtenus à partir de ces deux études de cas mettent en évidence l'existence de modifications de l'activité et de l'utilisation des ressources par les grands mammifères herbivores en fonction de leur état et en réponse aux variations environnementales.

A l'heure actuelle, de nombreuses populations de vertébrés sont soumises directement ou indirectement à des pressions anthropiques. Le but de ce mémoire est de montrer les implications de telles pressions sur la dynamique des populations d'ongulés, en plus des facteurs de variation environnementale classiquement reconnus, comme le climat ou la qualité de l'habitat. Nous présentons ici deux études de cas : le mouflon méditerranéen (Ovis gmelini musimon × Ovis sp.) en France et l'élan (Alces alces) en Norvège. Notre travail sur le mouflon s'est appuyé sur une étude à long terme (30 ans) d'une population située dans le sud de la France (Hérault). Pour l'élan, nous avons conduit une étude comparative de plusieurs populations évoluant dans des habitats très contrastés répartis en Norvège le long d'un gradient latitudinal.<br /><br />Après avoir mis en évidence dans notre étude sur le mouflon les avantages et les limites de méthodes classiquement utilisées pour le suivi des populations d'ongulés, nous montrons que la dynamique de cette population est influencée à la fois par (1) la fermeture généralisée des habitats suite à la déprise pastorale obligeant les mouflons à utiliser des ressources sous-optimales, (2) la chasse sélective pratiquée sur les mâles à trophée, (3) l'histoire récente des individus à l'origine de la population, ainsi que (4) la sécheresse estivale. Ces processus sont respectivement responsables d'une diminution de la qualité phénotypique (poids, trophée) des mouflons (processus (1) et (2)), des variations de performances reproductives des femelles (processus (3) et (4)) et de la mortalité estivale des agneaux (processus (4)).<br /><br />Chez l'élan, nous montrons que le dimorphisme sexuel de taille (DST) augmente avec une saisonnalité environnementale croissante, sans doute à cause d'une meilleure qualité des ressources lorsque la saison de végétation est plus courte mais plus intense. La chasse sélective contre les mâles intervient elle aussi sur le DST en causant une diminution de la proportion de mâles adultes dans la population. Les jeunes mâles participeraient alors davantage à la reproduction, ce qui affecterait en retour leur croissance.<br /><br />Les résultats obtenus à partir de ces deux études de cas, conduites à des échelles spatiales différentes, mettent en évidence l'existence de caractéristiques inhérentes aux populations exploitées. Au même titre que les contraintes environnementales sous lesquelles elles évoluent, nous démontrons que l'Homme peut influencer fortement la démographie de ces populations.

Successful management of bighorn sheep depends on understanding the mechanisms responsible for population growth or decline, habitat selection, and utilization distribution after translocations. We studied a declining population of desert bighorn sheep in the North San Rafael Swell, Utah to determine birthdates of neonates, demographics, limiting factors, population size, probable cause of death, production, and survival. We documented 19 mortalities attributed to a variety of causes including cougar predation (n = 10, 53%), bluetongue virus (n = 2, 11%), reproductive complications (n = 2, 11%), hunter harvest (n = 1, 5%), and unknown (n = 4, 21%). Annual survival of females was 73% (95% CI = 0.55—0.86) in 2012 and 73% (95% CI = 0.55—0.86) in 2013. Adult male survival was 75% in 2012 (95% CI = 0.38—0.94) and 88% (95% CI = 0.50—0.98) in 2013. Disease testing revealed the presence of pneumonia-related pathogens. The population increased from an estimated 127 in 2012 to 139 in 2013 (λ = 1.09). Lamb:ewe ratios were 47:100 in 2012 and 31:100 in 2013. Mean birthing dates were 21 May in 2012 and 20 May in 2013. Spatial separation from domestic sheep and goats, and aggressive harvest of cougars, may have aided in the recovery of this population after disease events. Second, we investigated the timing of parturition and nursery habitat of desert bighorn sheep in the North San Rafael Swell to determine the influence of vegetation, topography, and anthropogenic features on resource selection. We monitored 38 radio-tagged ewes to establish birthing dates. We documented birthdates of 45 lambs. We used collar-generated GPS locations to perform logistic regression within a model-selection framework to differentiate between nursery and random locations (n = 750 for each) based on a suite of covariates. The top model included elevation, slope, ruggedness, aspect, vegetation type, distance to trails, and distance to roads. We used these variables to create a GIS model of nursery habitat for the North San Rafael (desert bighorns) and the Green River Corridor (Rocky Mountain bighorns). Ewes showed preference for steep, north-facing slopes, rugged terrain, lower elevation, and avoidance of roads. Our model provides managers with a map of high probability nursery areas of desert and Rocky Mountain bighorns to aid in conservation planning and mitigate potential conflicts with industry and domestic livestock. Finally, we monitored 127 reintroduced female bighorn sheep in three adjacent restored populations to investigate if the size and overlap of habitat use by augmented bighorns differed from resident bighorns. The size of seasonal ranges for residents was generally larger than augmented females. However, there was a shift in utilization distribution in all three populations after augmentation. Overlap indices between resident and augmented sheep varied by source herd. These data will help managers understand the dynamics of home range expansion and the overlap between provenance groups following augmentations.

Reintroduction of Anatolian mouflon population at Bozdag Protection &amp / Breeding Station to its former habitats(Emremsultan Wildlife Development Area in Ankara-Nallihan, and Karadag in Karaman) started in 2004. The magnitude of genetic change among Bozdag and reintroduced populations was evaluated by 11 microsatellite loci. Study populations revealed close results (&plusmn / st.dev.) &ndash / Bozdag population: nk = 2.9091 (&plusmn / 1.1362), AE = 2.0250 (&plusmn / 0.9537), Ho = 0.3830 (&plusmn / 0.2717), He = 0.3956 (&plusmn / 0.2746) / Nallihan population: nk = 2.9091 (&plusmn / 1.1362), AE = 2.0592 (&plusmn / 0.9451), Ho = 0.4086 (&plusmn / 0.2977), He = 0.4052 (&plusmn / 0.2767) / and Karadag population: nk = 2.5455 (&plusmn / 1.1282), AE = 1.8809 (&plusmn / 0.8758), Ho = 0.3388 (&plusmn / 0.2775), He = 0.3607 (&plusmn / 0.2716). Population differences for major genetic parameters were not significant (p &gt / 0.05) by comparisons with paired t-test. Also, temporal change in genetic diversity for Bozdag population was investigated by comparison with temporal data. Temporal changes in genetic parameters were found to be not significant and possible causes for differences were argued. Additionally, genetic diversity and PI computations for different traps were verified and compared to uncover any potential bias due to the catching method. Comparisons did not reveal significant differences illustrating the homogeneity among traps. On the other hand, simulations detected the higher sensitivity of allelic diversity (A) to founder events than P and heterozygosity (Ho &amp / He) levels which supports heterozygosity excess method for bottleneck analysis. With the same simulation analysis, observed genetic diversity within reintroduced samples were found to be in the ranges of expectation (99% CI) indicating that translocated individuals were chosen randomly. Bottleneck analysis based on heterozygosity excess method (one-tailed test for heterozygosity excess: pSMM = 0.28515, pTPM = 0.06445, pIAM = 0.02441) and allele frequency distributions method (normal L-shaped) could not detect a recent genetic bottleneck for Bozdag population. However, simulations determined that these two methods are prone to type II error. Bottleneck detection failure for the study population is probably due to type II error instead of other sources of error like violations of model assumptions.

The Anatolian mouflon (Ovis gmelinii anatolica) is an endemic ungulate subspecies and of IUCN Vulnerable status that inhabits Konya-Bozdag region located in Central Anatolia. In this thesis, the demography and habitat use of the only natural population of Anatolian mouflon at Konya-Bozdag Provice is studied. Throughout the study, distance sampling techniques, specifically line transect sampling, are used to estimate density, size and growth rate of this population. Sex, age and count data are used to estimate relevant parameters. Changes in population structure and seasonal area use are monitored for two years. Data is collected during repeated random line transects from May 2007 to July 2009. Line transect method is preferred since it requires less effort and is less expensive when compared to the complicated techniques that need animal marking or radio tagging. In total, 78 transect lines were surveyed during the time which covers 3 lambing periods. In spite of the paratuberculosis epidemics in the fenced area which has affected the population adversely in the previous years, a rather stable population trend is observed. The post-breeding population size in 2007, 2008 and 2009 were estimated to be 883+-241, 939+-136, 972+-243 (average+-satndard error) and densities as 27.227, and 28.186 individuals per sq km, respectively. Growth rate of population is found using the ratio of the population size estimates of consecutive years from 2007 to 2009, average 1.0495+-0.0203. Habitat use patterns of the Anatolian mouflon throughout the study period are investigated according to seasons and sex groups. There is sexual segregation in the Anatolian mouflon population in Konya Bozdag Province, with the females using the western part and males using the eastern part of Bagderesi. Seasonal patterns affect on the area use of animals, group formation and compositions and the relationship between them are searched throughout the study. The movements of the individuals and groups followed seasonal patterns as centers of activities changed according to seasons.

Human encroachment into wilderness areas can influence the persistence of wildlife populations by decreasing and degrading habitat, displacement, and decreasing survival. For bighorn sheep (Ovis canadensis), some human activities are detrimental, causing both physiological stress and habitat abandonment. Between 1979 and 2000, human recreation has increased over 300% in areas occupied by desert bighorn sheep (O. c. nelsonii) in southeastern Utah. We investigated if an increase in human activity in areas used by bighorns affected their behavior. We observed 34 bighorn sheep using focal-animal sampling for >14 hrs to compare time spent grazing and scanning between areas of high and low human use. We identified group size, presence or absence of a lamb, distance to escape terrain, and human use (high versus low) as potential explanatory variables that influenced grazing and scanning times, and created an a priori list of models based on these variables. We used Akaike's Information Criterion adjusted for small sample sizes (AICc) to rank models, and used model selection to find a best approximating model (lowest AICc value) for both behaviors. Desert bighorn sheep spent less time grazing and more time scanning in high human use areas (22% grazing, 29% scanning) than in low human use areas (54% grazing, 8% scanning). Caution should be taken when considering which areas or trails should be opened during these important seasons to minimize and reduce additional stresses to bighorns caused by human activity. Bighorn sheep populations experienced significant declines after European settlement in North America. Today, the primary practice of bighorn sheep conservation is through population restoration and augmentation from remnant source populations. We conducted a 9-year telemetry study for a source population of desert bighorn sheep in Canyonlands National Park, Utah. We captured and collared 58 bighorn sheep from 2002-2009. To estimate annual and seasonal survival, we used known-fate analysis in Program MARK 4.1. We used model selection to test hypotheses for bighorn survival, including sex, age, human use, year, and month, as possible explanatory variables. There were 20 mortalities during the study. Annual survival ranged from 83% - 88% with no significant variation among any of the years. Model selection results showed that the top six models included a temporal variable (e.g. season or month), and carried 92% of the AICc weight. Population persistence for bighorn sheep can be compromised by high levels of predation, habitat fragmentation, and disease transmitted from domestic sheep. We suggest that land managers continue to maintain the separation of domestic sheep from bighorns in CNP. We also recommend that survival studies continue to ensure that future translocation projects do not occur at the expense of the source population.