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1.
J Vet Diagn Invest ; : 10406387241263329, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101552

RESUMEN

Osteoarthritis is a common cause of morbidity and mortality in geriatric gazelles. Propionibacterium australiense has been reported as a cause of systemic granulomas in cattle, but there are no descriptions of this bacteria infecting other species nor causing osteoarthritis, to our knowledge. An 8-y-old, castrated male, sand gazelle (Gazella leptoceros leptoceros) was managed for chronic, intermittent, progressive osteoarthritis of the right tarsus. Serial biopsies revealed pyogranulomatous dermatitis with intralesional bacteria. Serial diagnostic imaging identified osseous and soft tissue proliferation with draining tracts. Treatments over 1 y included broad-spectrum antibiotics, anti-inflammatories, joint debridement, and infusion with platelet-rich plasma and stem cells. Despite therapy, lameness persisted, azotemia developed, and subsequently, the animal was euthanized. On postmortem examination, the periarticular tissue of the right tarsus was markedly expanded by pyogranulomas and fibrosis. Histologically, the synovium, joint capsule, and overlying soft tissues were markedly expanded by pyogranulomas and numerous gram-positive and acid-fast-negative filamentous bacteria surrounded by Splendore-Hoeppli material. Within the joint, there was regionally extensive cartilage ulceration, osteonecrosis, osteolysis, and pannus formation. PCR assay of affected formalin-fixed, paraffin-embedded tissue amplified segments of 16S rRNA and ß subunit of bacterial RNA polymerase (rpoB) genes with 99.7% and 95.6% identity to P. australiense. This bacterium should be considered a differential for chronic pyogranulomatous osteoarthritis in gazelles.

2.
Curr Zool ; 69(6): 643-653, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37876648

RESUMEN

Reproductive traits are central to organismal fitness, and so the factors influencing patterns of reproduction and offspring survival are at the heart of biology. Making use of breeding data collected over 16 years at the King Khalid Wildlife Research Centre in Saudi Arabia, we investigated the reproductive biology of Arabian gazelles Gazella arabica. Offspring survival was mainly a function of birth weight, with heavier offspring having higher survival rates than lighter offspring. However, while sons were heavier than daughters, daughters had higher survival rates. We could not find evidence that giving birth to sons negatively impacts offspring weight in the following year. We uncovered large narrow-sense heritability (h2) in offspring weight at birth, while maternal effects (m2) on birth weight were of lesser importance. However, maternal effects on offspring survival were strong until weaning age, while paternal effects dominated survival to sexual maturity and first reproduction. We propose that variation in maternal postnatal care might overshadow the effects of maternal inheritance of birth weights, while the overall strong heritability of weight at birth and the paternal effects on survival illustrates strong variance in sire fitness based on genetic quality, suggesting a role for sexual selection by female mate choice in wild populations.

3.
Small Bus Econ (Dordr) ; 59(1): 269-278, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38624728

RESUMEN

Gazelles (high-growth), unicorns (ventures valued at $1 billion), and decacorns (ventures valued at $10 billion) appear to be dominating the landscape of entrepreneurship. In 2021, there were more than 700 ventures that have been valued at $1 billion or more by venture capitalists, and there seems to be a continued trend in more arising. However, the facts show that small- and medium-sized enterprises (SMEs) account for over 90% of businesses and 50% of employment of the worldwide population, contributing up to 55% of GDP in developed economies. Thus, it is clear that in developed countries, small firms are the economy. However, the entire realm of entrepreneurship appears to drifting slowly away from the importance of smaller firms and focusing the entire emphasis on the relatively few tech giants. These giant corporations are now viewed through the prism of entrepreneurship. Thus, we ask quo vadis - where will the focus of entrepreneurship be post-COVID-19 - centralization or democratization? For researchers and policy makers, shedding some light on this question may help in the formulation of research agendas and policy directions.

4.
BMC Ecol Evol ; 21(1): 213, 2021 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-34839826

RESUMEN

BACKGROUND: The islands in the Persian Gulf are home to several species of gazelles, i.e., Gazella bennettii, G. subgutturosa, and a new subspecies of Mountain gazelles which was discovered on Farur Island and described for the first time in 1993 as Gazella gazella dareshurii. Later, phylogenetic analyses showed that the Mountain gazelles consist of two species: G. gazella and G. arabica. As the Farur gazelles are more closely related to the Arabian forms of the Mountain gazelles, this subspecies is regarded to be G. arabica dareshurii. Until now, the origin of this subspecies has been an enigma. RESULTS: Here, we used mitochondrial cyt b, two nuclear introns (CHD2 and ZNF618), and morphological data to address this question by investigating the taxonomic position of the Farur gazelles. The results show that this population is monophyletic and split from other G. arabica populations probably 10,000 BP. CONCLUSIONS: It is a natural relict population that was trapped on the island due to the rising sea levels of the Persian Gulf after the Last Glacial Maximum. Intermittent drought and flooding are suggested to be the main factors balancing population growth in the absence of natural predators on this monsoon-influenced island. Conservation actions should focus on preserving the natural situation of the island (cease introducing mesquite tree and other invasive species, stop building new construction and roads, and caution in providing water sources and forage), and possibly introducing individuals to other islands (not inhabited by gazelles) or to fenced areas on the Iranian mainland (strictly isolated from other gazelle populations) when the population reaches the carrying capacity of the island.


Asunto(s)
Antílopes , Animales , Conservación de los Recursos Naturales , Humanos , Irán , Filogenia
5.
Vet Sci ; 8(10)2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34679070

RESUMEN

Anthelmintics are frequently administered to animals to limit fecal egg elimination, so that wild animals in captive breeding programs are treated to maintain a proper health condition. This is effective from a health management perspective, but on the other hand, it could prevent captive animals from developing an effective immunity against parasites that they might encounter when reintroduced into their original geographic areas. The aim of this study was to describe the dynamics of parasite infections in captive Cuvier's gazelles (Gazella cuvieri) not treated with anthelmintics for two years and to evaluate the factors related to their fecal egg shedding. Fifteen one-year-old males were enclosed together and captured monthly to collect feces directly from the rectum. Fecal egg counts were performed, and eggs were classified as strongylid-like, Nematodirus sp., or Trichuris sp. Fecal egg shedding for the three groups of parasites did not vary significantly over the duration of the study. Only precipitation affected the egg-shedding pattern of all parasites, while inbreeding was positively associated with the number of strongylid-like parasites. These findings suggest an equilibrium between hosts and parasites in absence of treatment during the study. The anthelmintic treatment as a systematic prophylaxis method in captive animals should be avoided and replaced by systematic coprological and clinical vigilance, as well as targeted treatment in the case of a significant rise of fecal egg counts.

6.
Theriogenology ; 88: 131-133, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27771116

RESUMEN

Coxiella (C.) burnetii is the etiological agent of the zoonotic disease known a Q fever. This agent can infect multiple hosts although its pathogenic potential in wild ruminants has been poorly studied. The polymerase chain reaction and the serological test detected the presence of C. burnetii in a population of North African gazelles (n = 355), comprising dorcas gazelle (Gazella dorcas neglecta), dama gazelle (Nanger dama mhorr) and Cuvier's gazelle (Gazella cuvieri) which, some of them, they recently aborted. Serological tests for Brucella spp., C. burnetii, Chlamydophila abortus, border disease pestivirus, and Toxoplasma spp. were performed together with specific cultures to detect Salmonella spp., Listeria spp., and Campylobacter spp. and a polymerase chain reaction for C. burnetii on serum and vaginal swabs samples collected from a representative number of animals (n = 65). These tests only detected the presence of C. burnetii in 18 specimens (27.3%). C. burnetii was the only pathogen detected, with eight animals testing positive on the polymerase chain reaction, 15 on the serological test, and five on both the tests. This article reveals the presence of C. burnetii during a medium and late-stage abortions occurred in a population of North African gazelles. The presence of C. burnetii as causal agent of abortions in Cuvier's gazelles has never been reported. The consequences of the findings are discussed here, showing the need to adopt urgent control measures to prevent the spread of C. burnetii in captive populations that are essential for the conservation of these endangered species.


Asunto(s)
Aborto Veterinario/microbiología , Antílopes , Coxiella burnetii/aislamiento & purificación , Complicaciones Infecciosas del Embarazo/veterinaria , Fiebre Q/veterinaria , Animales , Especies en Peligro de Extinción , Femenino , Masculino , Embarazo , Pruebas Serológicas/veterinaria
7.
Mol Ecol Resour ; 15(3): 652-61, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25256349

RESUMEN

North African ungulates include several threatened and emblematic species, yet are poorly studied mainly due to their remoteness and elusiveness. Noninvasive sampling provides a useful approach to obtain ecological and genetic information essential to guide conservation actions. The very first and most important step in conservation planning is to accurately identify species, and molecular genetics has been proved to be a useful tool. Several molecular genetics protocols are available for species identification, even for samples with poor quality DNA, such as faeces, hairs or bones. Most of these protocols use mitochondrial DNA for barcoding despite this marker being especially prone to problems, including mtDNA introgression, nuclear insert copies, high intraspecific diversity or heteroplasmy. In this work, we developed a molecular method based on polymorphisms in small fragments of the mitochondrial cytochrome b (cytb, mtDNA) and the nuclear kappa casein genes (KCAS, nDNA) for identifying endangered North African ungulates. These fragments revealed polymorphisms, including species-specific variation, which allowed species identification of nine ungulate species that co-occur in North Africa. The method was validated across more than 400 samples, including different types of noninvasive samples collected in the field. The simplicity, high reliability and relative low cost of the described method make it a promising tool to improve ecological studies of the North African ungulates and consequently, the implementation of more efficient management and conservation plans for these endangered ungulates.


Asunto(s)
Dermatoglifia del ADN/métodos , Mamíferos/clasificación , Mamíferos/genética , África del Norte , Animales , Caseínas/genética , Costos y Análisis de Costo , Citocromos b/genética , ADN/química , ADN/genética , ADN/aislamiento & purificación , Variación Genética , Datos de Secuencia Molecular , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN
8.
Oecologia ; 73(1): 32-40, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28311402

RESUMEN

The population of Thomson's gazelles in the Serengeti National Park, Tanzania has declined by almost two thirds over a 13 year period. In the early 1970s, numbers stood at 0.66 million animals but had decreased to less than 0.25 million animals in 1985 as estimated by 5 different censuses using two different counting techniques. Predation, interspecific competition and disease are all factors that could have contributed to this decline, and at least one of these factors, predation, could now prevent the Thomson's gazelle population from increasing.

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