Monogeneans from Catfishes in Lake Tanganyika. II: New Infection Site, New Record, and Additional Details on the Morphology of the Male Copulatory Organ of Gyrodactylus transvaalensis Prudhoe and Hussey, 1977.

The ichthyofauna of Lake Tanganyika consists of 12 families of fish of which five belong to Siluriformes (catfishes). Studies on Siluriformes and their parasites in this lake are very fragmentary. The present study was carried out to help fill the knowledge gap on the monogeneans infesting the siluriform fishes of Lake Tanganyika in general and, more particularly, Clarias gariepinus. Samples of gills of Clarias gariepinus (Clariidae) were examined for ectoparasites. We identified the monogenean Gyrodactylus transvaalensis (Gyrodactylidae). This is the first time this parasite was found infecting gills. We are the first to observe a large spine in the male copulatory organ of this species and to provide measurements of its genital spines; this completes the description of the male copulatory organ, which is important in standard monogenean identification. This is the first monogenean species reported in C. gariepinus at Lake Tanganyika and the third known species on a representative of Siluriformes of this lake. It brings the total number of species of Gyrodactylus recorded in Lake Tanganyika to four. Knowing that other locations where this species has been reported are geographically remote from Lake Tanganyika, we propose a "failure to diverge" phenomenon for G. transvaalensis.

Molecular Detection of Avian Influenza Virus in Wild Birds in Morocco, 2016-2019.

Avian influenza (AI) is a zoonotic disease significant to both public and animal health, caused by influenza virus A, and affects domestic poultry, wild birds, and mammals including humans. Aquatic birds are considered the natural reservoir of this virus. In 2016, Morocco experienced the first occurrence of low pathogenic H9N2 avian influenza virus (AIV) in poultry; however, no cases were reported in wild birds. The present study aimed to monitor the presence of AIV in wild birds in Morocco in order to trace the possible sources of the viruses affecting poultry. Between 2016 and 2019, 967 samples obtained from 480 birds representing 56 different wild bird species, 20 families, and 8 orders, mostly from Charadriiformes, Anseriformes, Pelecaniformes, and Passeriformes, were collected from various wetlands and relevant ornithologic sites in Morocco. These field samples consisted of 374 cloacal swabs, 321 tracheal swabs, 54 fecal samples, and 218 organ pools including the trachea, lung, liver, spleen, heart, intestine, and brain. The samples were examined for the presence of AIV using TaqMan-based real-time reverse transcriptase-PCR (rRT-PCR) targeting the matrix gene, followed by further subtyping rRT-PCR tests targeting the H1-H16 genes. The AI matrix gene was detected in 18 out of 967 samples (1.86%); positive samples were detected in 17 birds belonging to 10 bird species: two redshanks (Tringa totanus), one little stint (Calidris minuta), one ruddy turnstone (Arenaria interpres), one common snipe (Gallinago gallinago), one common greenshank (Tringa nebularia), one black-winged stilt (Himantopus himantopus), two black-headed gulls (Chroicocephalus ridibundus), one slender-billed gull (Chroicocephalus genei), six cattle egrets (Bubulcus ibis), and one Eurasian coot (Fulica atra). AIV was detected in 2 wetlands and 1 ornithologic site (Sidi Moussa Oualidia Complex, Smir lagoon and El Jadida Coast) and the highest positivity was revealed in fresh fecal samples (11.1%), indicating the suitability of this matrix for wild bird surveillance. Our results highlight that waders, gulls, and cattle egrets are the most affected species and may represent a potential risk for AI introduction in the poultry sector in Morocco. Regular monitoring of wild birds in Morocco, focusing in particular in the areas and species identified in this study as a high risk of virus circulation, should be implemented to anticipate and prevent possible AIV spread.

Detección molecular del virus de la influenza aviar en aves silvestres en Marruecos, entre los años 2016 al 2019. La influenza aviar (IA) es una enfermedad zoonótica importante para la salud pública y animal, causada por el virus de la influenza A y afecta a la avicultura comercial, las aves silvestres y los mamíferos, incluyendo a los humanos. Las aves acuáticas se consideran el reservorio natural de este virus. En el año 2016, Marruecos experimentó la primera aparición del virus de la influenza aviar de baja patogenicidad H9N2 en avicultura; sin embargo, no se notificaron casos en aves silvestres. El presente estudio tuvo como objetivo monitorear la presencia del virus de influenza aviar en aves silvestres en Marruecos con el fin de rastrear las posibles fuentes de los virus que afectan a las aves comerciales. Entre los años 2016 y 2019, se recolectaron 967 muestras de 480 aves que representan 56 especies diferentes de aves silvestres, 20 familias y 8 órdenes, principalmente de Charadriiformes, Anseriformes, Pelecaniformes y Passeriformes, de varios humedales y sitios ornitológicos relevantes en Marruecos. Estas muestras de campo consistieron en 374 hisopos cloacales, 321 hisopos traqueales, 54 muestras fecales y 218 conjuntos de órganos que incluyeron tráquea, pulmón, hígado, bazo, corazón, intestino y cerebro. Las muestras se examinaron para detectar la presencia del virus de la influenza aviar mediante transcripción reversa y PCR en tiempo real basada en TaqMan (rRT-PCR) que estivo dirigida al gene de la matriz, seguida de más pruebas de subtipificación de rRT-PCR dirigidas a los genes H1 al H16. El gene de la matriz de influenza aviar se detectó en 18 de 967 muestras (1.86%); Se detectaron muestras positivas en 17 aves pertenecientes a 10 especies de aves: dos archibebes comunes (Tringa totanus), un correlimos chico (Calidris minuta), un vuelvepiedras común (Arenaria interpres), una agachadiza común (Gallinago gallinago), un archibebe claro (Tringa nebularia), una cigüeñuela común (Himantopus himantopus), dos gaviotas reidoras (Chroicocephalus ridibundus), una gaviota picofina (Chroicocephalus genei), seis garzas ganaderas (Bubulcus ibis) y una focha común (Fulica atra). El virus de la influenza aviar se detectó en 3 de los 17 humedales (Complejo Sidi Moussa-Walidia, Costa El Jadida y Laguna Smir) y la mayor positividad se reveló en muestras fecales frescas (11.1%), lo que indica la idoneidad de esta matriz para la vigilancia de aves silvestres. Estos resultados destacan que las aves zancudas, las gaviotas y las garzas ganaderas son las especies más afectadas y pueden representar un riesgo potencial para la introducción de influenza aviar en el sector avícola de Marruecos. Se debe implementar un monitoreo regular de las aves silvestres en Marruecos, centrándose en particular en las áreas y especies identificadas en este estudio como de alto riesgo de circulación del virus, para anticipar y prevenir la posible propagación del virus de la influenza aviar.

Spatiotemporal Dynamics, Evolutionary History and Zoonotic Potential of Moroccan H9N2 Avian Influenza Viruses from 2016 to 2021.

The H9N2 virus continues to spread in wild birds and poultry worldwide. At the beginning of 2016, the H9N2 Avian influenza virus (AIV) was detected in Morocco for the first time; despite the implementation of vaccination strategies to control the disease, the virus has become endemic in poultry in the country. The present study was carried out to investigate the origins, zoonotic potential, as well as the impact of vaccination on the molecular evolution of Moroccan H9N2 viruses. Twenty-eight (28) H9N2 viruses collected from 2016 to 2021 in Moroccan poultry flocks were isolated and their whole genomes sequenced. Phylogenetic and evolutionary analyses showed that Moroccan H9N2 viruses belong to the G1-like lineage and are closely related to viruses isolated in Africa and the Middle East. A high similarity among all the 2016-2017 hemagglutinin sequences was observed, while the viruses identified in 2018-2019 and 2020-2021 were separated from their 2016-2017 ancestors by long branches. Mutations in the HA protein associated with antigenic drift and increased zoonotic potential were also found. The Bayesian phylogeographic analyses revealed the Middle East as being the region where the Moroccan H9N2 virus may have originated, before spreading to the other African countries. Our study is the first comprehensive analysis of the evolutionary history of the H9N2 viruses in the country, highlighting their zoonotic potential and pointing out the importance of implementing effective monitoring systems.

Influence of age on the bioaccumulation of heavy metals in Apodemus sylvaticus at Merja Zerga lagoon, Morocco.

The influence of age and sex on the bioaccumulation of heavy metals in Apodemus sylvaticus was studied in Merja Zerga lagoon in northern Morocco. Five trace metal elements (Zn, Pb, Cr, Cu and Fe) were quantitatively analyzed by Varian AA 240 atomic absorption spectroscopy with graphite furnace in three organs (Liver, Kidney and Heart) from animals of different age and sex. The maximum metal level of the analyzed samples was recorded in adults and was limited to 46.62 µg/g for Pb and 35.1 µg/g for Cu, while it reached 22.69 µg/g, 7.59 µg/g and 6.78 µg/g for Cr, Zn and Fe, respectively. Highly significant differences were found for bioaccumulation of heavy metals according to animal ages and no significant differences were observed between the two sexes among the studied animals. Our results revealed also the existence of a strong correlation (r > 0.65) between the majority of biometric parameters and the trace element concentrations. In general, we found that age is a critical factor in estimating the level of heavy metal pollution. Other characteristics such as habitat, feeding habits and anti-predator behavior of the species need to be studied.

Notes on the distribution and phylogeography of two rare small Gerbillinae (Rodentia, Muridae) in Morocco: Gerbillus simoni and Gerbillus henleyi.

Even though Gerbillinae rodents represent an important part of the mammalian fauna in North Africa, many gaps remain in our understanding of the distribution, ecology, evolution, and systematics of some lesser known species in this family. We present in this study the most recent findings on two of these species. The first species, Gerbillus simoni Lataste, 1881, is a short-tailed, small gerbil, endemic to North Africa. In Morocco, it is present only in a small area in the northeast, where it has not been caught since 1970. In 2014, we captured a small gerbil in this region that was identified as G. simoni based on morphology and molecular data (cytochrome b gene sequencing). This study represents the first genetic characterization of G. simoni in Morocco and the first one outside Tunisia. Populations from Morocco and Tunisia (mainland and Kerkennah Islands) show very little genetic differentiation. The second species, Gerbillus henleyi de Winton, 1903, is a long-tailed small gerbil that lives in the Sahel and North Africa with an extension to the Middle East. In Morocco, this species was only known in the southwest. Between 2014 and 2015, we have captured four gerbils in the northeast of the country, which were confirmed genetically and morphologically as belonging to this species. This represents an extension of its known distribution of about 370km to the northeast of the country. These new Moroccan specimens form a distinct lineage. High genetic diversity is observed throughout the geographic range of G. henleyi, suggesting the existence of several cryptic species.

A euryhaline fish, lost in the desert: The unexpected metapopulation structure of Coptodon guineensis (Günther, 1862) in the Sebkha of Imlili.

Euryhaline Cichlid fish of the species Coptodon guineensis are present in different water holes situated in a dried depression in the desert in the extreme South of Morocco, the Sebkha of Imlili. A genetic survey of this population, using complete sequences of the ND2 gene (mtDNA) and sixteen microsatellite loci, revealed that the fish in the sebkha did not form a single population, but rather a metapopulation. This metapopulational structure may be regarded as good news from the point of view of the conservation of fish in the sebkha. Although small individual populations may have short, finite life spans, the metapopulation as a whole is more stable, because immigrants from one population are likely to re-colonize the habitat, left open by the extinction of another.