Assessment of ecto and endo parasites of Schizothorax plagiostomus inhabiting river Panjkora, Khyber Pakhtunkhwa, Pakistan / Avaliação de ecto e endoparasitas de Schizothorax plagiostomus habitantes do rio Panjkora, Khyber Pakhtunkhwa, Paquistão

Abstract Fish provides main source of high quality protein to more than one billion people in the world. Fish parasites directly affect the productivity of fish and indirectly on human health. This research was aimed to assess the helminth parasites in Schizothorax plagiostomus (the snow trout) from river Panjkora, KP, Pakistan. A total of 88 fish samples (n= 88) were collected from the upper, middle and lower regions of the river through cast nets, hand nets and hooks. All the collected fish samples were examined in the Parasitology Laboratory, Department of Zoology, University of Malakand for helminth parasites during July 2018 to February 2019.Among these fishes nematodes, trematodes, cestodes and acanthocephalan were isolated and identified. Overall prevalence of the fish parasites was 60.22% (53/88). The intensity of the parasite was observed from 1.7% to 4.61%. Highest prevalence was reported in summer season 86.36% while lowest in the winter season 36.36%. This study shows that summer season affects the fish business and result in poor quality fish meat with risk of zoonotic diseases. Adults were highly infected 82.25% while no infection was found in juvenile specimens. Female fish samples had higher prevalence 68.22% than males 48.22%. Fishes of the lower reaches had highest prevalence 60.22% than the upper reaches 40.0%. Fish samples with maximum length and weight were highly 76.92% infected than small sized fish with low body weight. Present study addresses that Rhabdochona schizothoracis in the intestine and Diplozoon paradoxum in gills of snow trout fish has a long term relationship and call as a natural infection in cyprinids and it is zoonotic threat to human.

Resumo O peixe é a principal fonte de proteína de alta qualidade para mais de um bilhão de pessoas no mundo. Contudo, parasitas afetam diretamente a produtividade de peixes e, indiretamente, a saúde humana. Esta pesquisa teve como objetivo avaliar os parasitas helmintos em Schizothorax plagiostomus (truta da neve) do rio Panjkora, Khyber Pakhtunkhwa, Paquistão. Foram coletadas 88 amostras de peixes (n = 88) dos trechos alto, médio e baixo do rio por meio de redes de arrasto, redes de mão e varas de pesca. Todas as amostras de peixes coletadas foram examinadas no Laboratório de Parasitologia do Departamento de Zoologia, da Universidade de Malakand, quanto a parasitas helmintos durante o período de julho de 2018 a fevereiro de 2019. Entre esses peixes, nematódeos, trematódeos, cestóideos e acantocéfalos foram isolados e identificados. A prevalência geral de parasitas de peixes foi de 60,22% (53/88). A intensidade do parasita foi observada de 1,7 a 4,61%. A maior prevalência (86,36%) foi relatada no verão, enquanto a menor (36,36%), no inverno. Este estudo mostra que a temporada de verão afeta o ramo da pesca e resulta em carne de baixa qualidade, com risco de doenças zoonóticas. Os adultos foram altamente infectados (82,25%), enquanto nenhuma infecção foi encontrada em jovens. As amostras de peixes do sexo feminino apresentaram maior prevalência (68,22%) do que as do sexo masculino (48,22%). Os peixes coletados no trecho baixo do rio tiveram maior prevalência (60,22%) do que os do trecho alto (40%). Amostras de peixes com comprimento e peso máximos foram altamente infectadas (76,92%) do que peixes de pequeno porte e baixo peso corporal. O presente estudo aborda que Rhabdochona schizothoracis no intestino e Diplozoon paradoxum em brânquias de peixes de truta da neve possuem uma estreita relação que causa uma infecção natural em ciprinídeos, sendo uma ameaça zoonótica ao ser humano.

Evaluation of ecto and endo parasitic fauna of Schizothorax plagiostomus inhabitants of river Swat, Khyber PakhtunKhwa, Pakistan / Avaliação da fauna ecto e endoparasitária de Schizothorax plagiostomus habitantes do rio Swat, Khyber Pakhtunkhwa, Paquistão

Abstract Fish is consumed as a rich and cheaper source of white meat and proteins all over the world. Fish farming is the leading source of income generation throughout the world. The present research study was conducted with aims to investigate the ecto and endo parasitic fauna of S. plagiostomus (snow trout) in River Swat. A total of 96 fish samples were collected on monthly basis from July-2018 to February-2019, from upper, middle and lower reaches. Fish samples were collected with the help of cast net, hand net and fishing rods. Local fishermen and experts help were also sought out for fish collection. 61 out of 96 fishes were found infected by helminth parasites. The total prevalence and intensity of 63.54% and 2.90 was observed respectively during data analysis. Highest monthly prevalence of 83.33% was recorded during July and August, while lowest prevalence of 33.33% was noted during February. Five species of helminths parasites were detected from S. plagiostomus, of which two were trematodes (Rhabdochona shizothoracis and Rhabdochona species), one species of Monogenia (Diplozoon paraddoxum), one species of Cestodes (Nippotaenia species), and one species of Acanthocephalan (Neoechynorhynchus devdevi). Highest parasite wise prevalence, intensity and relative density of 21.87%, 4.09 and 0.895 was noted for R. schizothoracis while the lowest prevalence, intensity and relative density of 4.16%, 1.25 and 0.052 was noted for N. devdevi. Highest infection of 76.08% was observed in adults host while lowest, 40% infestation rate was observed in young fish samples. 73.68% prevalence was observed in female hosts while only 56.90% prevalence was observed in male individuals. Higher infection (83.33%) was noticed during summer season, while lowest infection (44.44%) was observed during winter season. Similarly 71.79% fishes were found infected that were collected from lower reaches of the River Swat than the fish samples collected from upper reaches (52%).

Resumo O peixe é consumido mundialmente por ser uma fonte rica e barata de carne branca e proteínas. A piscicultura é a principal fonte de geração de renda em todo o mundo. O presente estudo foi conduzido com o objetivo de investigar a fauna ecto e endoparasitária de S. plagiostomus (truta da neve) no rio Swat. Foram coletadas mensalmente 96 amostras de peixes, no período de julho de 2018 a fevereiro de 2019, nos trechos alto, médio e baixo com auxílio de redes de arrasto, redes de mão e varas de pesca. Pescadores locais e especialistas também ajudaram na coleta de peixes. Dos 96 peixes encontrados, 61 estavam infectados por parasitas helmintos. A prevalência de 63,54% e a intensidade total de 2,90 foram observadas durante a análise dos dados. A maior prevalência mensal de 83,33% foi registrada nos meses de julho e agosto, enquanto a menor, de 33,33%, em fevereiro. Cinco espécies de parasitas helmintos foram detectadas de S. plagiostomus, dos quais dois eram trematódeos (espécies Rhabdochona shizothoracis e Rhabdochona), uma espécie de monogenia (Diplozoon paradoxum), uma espécie de cestóideos (espécie Nippotaenia) e uma espécie de acantocéfalo (Neoechynorhynchus devdevi). As maiores prevalências de parasitas (21,87%), intensidade (4,09) e densidade relativa (0,895) foram observadas em R. schizothoracis, enquanto as menores prevalências de parasitas (4,16%), intensidade (1,25) e densidade relativa (0,052), em N. devdevi. A infecção mais alta (76,08%) foi constatada em adultos hospedeiros, ao passo que a taxa de infestação mais baixa (40%) foi encontrada em amostras de peixes jovens. A prevalência de 73,68% foi verificada em hospedeiros do sexo feminino, enquanto a de 56,90%, em indivíduos do sexo masculino. Maior infecção (83,33%) foi observada durante a temporada de verão, e a menor infecção (44,44%), durante o inverno. Da mesma forma, 71,79% dos peixes encontrados infectados foram coletados no trecho baixo do rio Swat, enquanto 52%, no trecho alto.

Roosting ecology and morphometric analysis of Pteropus medius (Indian flying fox) in Lower Dir, district, Pakistan / Ecologia de roosting e análise morfométrica de Pteropus medius (raposa-voadora indiana) no distrito de Lower Dir, Paquistão

Abstract The present study was conducted to explore morphometric variations of Pteropus medius (the Indian flying fox) and the roosting trees in Lower Dir, Pakistan. The bats were captured from Morus alba, Morus nigra, Brousonetia papyrifera, Pinus raxburghii, Hevea brasiliensis, Platanus orientalis, Populous nigra, Melia azedarach, Eucalyptus camaldulensis and Grevillea robusta through sling shot and mess net methods. A total of 12 bats were studied for the differential morphological features based on age and sex. Male bats were recorded higher in weight than females. The variations were found in body mass (821.1±34.65gm), circumference of body with wings (25.43±0.39cm), wingspan (112.58±1.90cm), Body length (20.73±0.68cm), Snout length (3.42±0.04cm), Eye length (1.45±0.033cm), Length of ear (3.56±0.05cm), Width of ear (2.46±0.04cm), Length b/w ear (5.51±0.11cm), Circumference of neck (12.23±0.24cm), Circumference of body without wings (18.68±0.31cm), Arm wing length (23.2±1.03cm), Length of thumb (5.43±0.1cm), Length of nail (1.89±0.05cm), Hand wing length (29.1±0.51cm), Maximum width of wing (21.03±0.68cm), Length b/w tip of wing to 5th digit (29.39±0.30cm), Length b/w 5th digit to foot (22.97±1.09cm), Length b/w feet (18.31±0.74cm) and Length of foot claw (4.23±0.05cm). This study was designed for analysis of external morphological variations for P. medius (the Indian flying fox) that may help in identification of these bats and their roosting sites.

Resumo O presente estudo foi conduzido com o intuito de explorar variações morfométricas de Pteropus medius (raposa-voadora indiana) e árvores de repouso em Lower Dir, Paquistão. Os morcegos foram capturados de Morus alba, Morus nigra, Broussonetia papyrifera, Pinus roxburghii, Hevea brasiliensis, Platanus orientalis, Populus nigra, Melia azedarach, Eucalyptus camaldulensis e Grevillea robusta por meio de estilingues e redes. Doze morcegos foram estudados quanto às características morfológicas diferenciais com base na idade e no sexo. Os morcegos machos apresentaram maior peso do que as fêmeas. As variações foram encontradas em massa corporal (821,1 ± 34,65 g), circunferência do corpo com asas (25,43 ± 0,39 cm), envergadura (112,58 ± 1,90 cm), comprimento do corpo (20,73 ± 0,68 cm), comprimento do focinho (3,42 ± 0,04 cm), comprimento do olho (1,45 ± 0,033 cm), comprimento da orelha (3,56 ± 0,05 cm), largura da orelha (2,46 ± 0,04 cm), comprimento entre as orelhas (5,51 ± 0,11 cm), circunferência do pescoço (12,23 ± 0,24 cm), circunferência do corpo sem asas (18,68 ± 0,31 cm), comprimento da asa da pata dianteira (23,2 ± 1,03 cm), comprimento do polegar (5,43 ± 0,1 cm), comprimento da unha (1,89 ± 0,05 cm), comprimento da asa até a ponta do dedo (29,1 ± 0,51 cm), largura máxima da asa (21,03 ± 0,68 cm), comprimento entre a ponta da asa e o quinto dedo (29,39 ± 0,30 cm), comprimento entre o quinto dedo e a pata (22,97 ± 1,09 cm), comprimento entre as patas (18,31 ± 0,74 cm) e comprimento da garra da pata (4,23 ± 0,05 cm). Este estudo foi desenvolvido para análise de variações morfológicas externas de P. medius (raposa-voadora indiana) e pode auxiliar na identificação desses morcegos e seus locais de nidificação.

Roosting ecology and morphometric analysis of Pteropus medius (Indian flying fox) in Lower Dir, district, Pakistan.

The present study was conducted to explore morphometric variations of Pteropus medius (the Indian flying fox) and the roosting trees in Lower Dir, Pakistan. The bats were captured from Morus alba, Morus nigra, Brousonetia papyrifera, Pinus raxburghii, Hevea brasiliensis, Platanus orientalis, Populous nigra, Melia azedarach, Eucalyptus camaldulensis and Grevillea robusta through sling shot and mess net methods. A total of 12 bats were studied for the differential morphological features based on age and sex. Male bats were recorded higher in weight than females. The variations were found in body mass (821.1±34.65gm), circumference of body with wings (25.43±0.39cm), wingspan (112.58±1.90cm), Body length (20.73±0.68cm), Snout length (3.42±0.04cm), Eye length (1.45±0.033cm), Length of ear (3.56±0.05cm), Width of ear (2.46±0.04cm), Length b/w ear (5.51±0.11cm), Circumference of neck (12.23±0.24cm), Circumference of body without wings (18.68±0.31cm), Arm wing length (23.2±1.03cm), Length of thumb (5.43±0.1cm), Length of nail (1.89±0.05cm), Hand wing length (29.1±0.51cm), Maximum width of wing (21.03±0.68cm), Length b/w tip of wing to 5th digit (29.39±0.30cm), Length b/w 5th digit to foot (22.97±1.09cm), Length b/w feet (18.31±0.74cm) and Length of foot claw (4.23±0.05cm). This study was designed for analysis of external morphological variations for P. medius (the Indian flying fox) that may help in identification of these bats and their roosting sites.

Assessment of ecto and endo parasites of Schizothorax plagiostomus inhabiting river Panjkora, Khyber Pakhtunkhwa, Pakistan.

Fish provides main source of high quality protein to more than one billion people in the world. Fish parasites directly affect the productivity of fish and indirectly on human health. This research was aimed to assess the helminth parasites in Schizothorax plagiostomus (the snow trout) from river Panjkora, KP, Pakistan. A total of 88 fish samples (n= 88) were collected from the upper, middle and lower regions of the river through cast nets, hand nets and hooks. All the collected fish samples were examined in the Parasitology Laboratory, Department of Zoology, University of Malakand for helminth parasites during July 2018 to February 2019.Among these fishes nematodes, trematodes, cestodes and acanthocephalan were isolated and identified. Overall prevalence of the fish parasites was 60.22% (53/88). The intensity of the parasite was observed from 1.7% to 4.61%. Highest prevalence was reported in summer season 86.36% while lowest in the winter season 36.36%. This study shows that summer season affects the fish business and result in poor quality fish meat with risk of zoonotic diseases. Adults were highly infected 82.25% while no infection was found in juvenile specimens. Female fish samples had higher prevalence 68.22% than males 48.22%. Fishes of the lower reaches had highest prevalence 60.22% than the upper reaches 40.0%. Fish samples with maximum length and weight were highly 76.92% infected than small sized fish with low body weight. Present study addresses that Rhabdochona schizothoracis in the intestine and Diplozoon paradoxum in gills of snow trout fish has a long term relationship and call as a natural infection in cyprinids and it is zoonotic threat to human.

Evaluation of ecto and endo parasitic fauna of Schizothorax plagiostomus inhabitants of river Swat, Khyber PakhtunKhwa, Pakistan.

Fish is consumed as a rich and cheaper source of white meat and proteins all over the world. Fish farming is the leading source of income generation throughout the world. The present research study was conducted with aims to investigate the ecto and endo parasitic fauna of S. plagiostomus (snow trout) in River Swat. A total of 96 fish samples were collected on monthly basis from July-2018 to February-2019, from upper, middle and lower reaches. Fish samples were collected with the help of cast net, hand net and fishing rods. Local fishermen and experts help were also sought out for fish collection. 61 out of 96 fishes were found infected by helminth parasites. The total prevalence and intensity of 63.54% and 2.90 was observed respectively during data analysis. Highest monthly prevalence of 83.33% was recorded during July and August, while lowest prevalence of 33.33% was noted during February. Five species of helminths parasites were detected from S. plagiostomus, of which two were trematodes (Rhabdochona shizothoracis and Rhabdochona species), one species of Monogenia (Diplozoon paraddoxum), one species of Cestodes (Nippotaenia species), and one species of Acanthocephalan (Neoechynorhynchus devdevi). Highest parasite wise prevalence, intensity and relative density of 21.87%, 4.09 and 0.895 was noted for R. schizothoracis while the lowest prevalence, intensity and relative density of 4.16%, 1.25 and 0.052 was noted for N. devdevi. Highest infection of 76.08% was observed in adults host while lowest, 40% infestation rate was observed in young fish samples. 73.68% prevalence was observed in female hosts while only 56.90% prevalence was observed in male individuals. Higher infection (83.33%) was noticed during summer season, while lowest infection (44.44%) was observed during winter season. Similarly 71.79% fishes were found infected that were collected from lower reaches of the River Swat than the fish samples collected from upper reaches (52%).

Roosting ecology and morphometric analysis of Pteropus medius (Indian flying fox) in Lower Dir, district, Pakistan

Abstract The present study was conducted to explore morphometric variations of Pteropus medius (the Indian flying fox) and the roosting trees in Lower Dir, Pakistan. The bats were captured from Morus alba, Morus nigra, Brousonetia papyrifera, Pinus raxburghii, Hevea brasiliensis, Platanus orientalis, Populous nigra, Melia azedarach, Eucalyptus camaldulensis and Grevillea robusta through sling shot and mess net methods. A total of 12 bats were studied for the differential morphological features based on age and sex. Male bats were recorded higher in weight than females. The variations were found in body mass (821.1±34.65gm), circumference of body with wings (25.43±0.39cm), wingspan (112.58±1.90cm), Body length (20.73±0.68cm), Snout length (3.42±0.04cm), Eye length (1.45±0.033cm), Length of ear (3.56±0.05cm), Width of ear (2.46±0.04cm), Length b/w ear (5.51±0.11cm), Circumference of neck (12.23±0.24cm), Circumference of body without wings (18.68±0.31cm), Arm wing length (23.2±1.03cm), Length of thumb (5.43±0.1cm), Length of nail (1.89±0.05cm), Hand wing length (29.1±0.51cm), Maximum width of wing (21.03±0.68cm), Length b/w tip of wing to 5th digit (29.39±0.30cm), Length b/w 5th digit to foot (22.97±1.09cm), Length b/w feet (18.31±0.74cm) and Length of foot claw (4.23±0.05cm). This study was designed for analysis of external morphological variations for P. medius (the Indian flying fox) that may help in identification of these bats and their roosting sites.

Resumo O presente estudo foi conduzido com o intuito de explorar variações morfométricas de Pteropus medius (raposa-voadora indiana) e árvores de repouso em Lower Dir, Paquistão. Os morcegos foram capturados de Morus alba, Morus nigra, Broussonetia papyrifera, Pinus roxburghii, Hevea brasiliensis, Platanus orientalis, Populus nigra, Melia azedarach, Eucalyptus camaldulensis e Grevillea robusta por meio de estilingues e redes. Doze morcegos foram estudados quanto às características morfológicas diferenciais com base na idade e no sexo. Os morcegos machos apresentaram maior peso do que as fêmeas. As variações foram encontradas em massa corporal (821,1 ± 34,65 g), circunferência do corpo com asas (25,43 ± 0,39 cm), envergadura (112,58 ± 1,90 cm), comprimento do corpo (20,73 ± 0,68 cm), comprimento do focinho (3,42 ± 0,04 cm), comprimento do olho (1,45 ± 0,033 cm), comprimento da orelha (3,56 ± 0,05 cm), largura da orelha (2,46 ± 0,04 cm), comprimento entre as orelhas (5,51 ± 0,11 cm), circunferência do pescoço (12,23 ± 0,24 cm), circunferência do corpo sem asas (18,68 ± 0,31 cm), comprimento da asa da pata dianteira (23,2 ± 1,03 cm), comprimento do polegar (5,43 ± 0,1 cm), comprimento da unha (1,89 ± 0,05 cm), comprimento da asa até a ponta do dedo (29,1 ± 0,51 cm), largura máxima da asa (21,03 ± 0,68 cm), comprimento entre a ponta da asa e o quinto dedo (29,39 ± 0,30 cm), comprimento entre o quinto dedo e a pata (22,97 ± 1,09 cm), comprimento entre as patas (18,31 ± 0,74 cm) e comprimento da garra da pata (4,23 ± 0,05 cm). Este estudo foi desenvolvido para análise de variações morfológicas externas de P. medius (raposa-voadora indiana) e pode auxiliar na identificação desses morcegos e seus locais de nidificação.

Assessment of ecto and endo parasites of Schizothorax plagiostomus inhabiting river Panjkora, Khyber Pakhtunkhwa, Pakistan

Abstract Fish provides main source of high quality protein to more than one billion people in the world. Fish parasites directly affect the productivity of fish and indirectly on human health. This research was aimed to assess the helminth parasites in Schizothorax plagiostomus (the snow trout) from river Panjkora, KP, Pakistan. A total of 88 fish samples (n= 88) were collected from the upper, middle and lower regions of the river through cast nets, hand nets and hooks. All the collected fish samples were examined in the Parasitology Laboratory, Department of Zoology, University of Malakand for helminth parasites during July 2018 to February 2019.Among these fishes nematodes, trematodes, cestodes and acanthocephalan were isolated and identified. Overall prevalence of the fish parasites was 60.22% (53/88). The intensity of the parasite was observed from 1.7% to 4.61%. Highest prevalence was reported in summer season 86.36% while lowest in the winter season 36.36%. This study shows that summer season affects the fish business and result in poor quality fish meat with risk of zoonotic diseases. Adults were highly infected 82.25% while no infection was found in juvenile specimens. Female fish samples had higher prevalence 68.22% than males 48.22%. Fishes of the lower reaches had highest prevalence 60.22% than the upper reaches 40.0%. Fish samples with maximum length and weight were highly 76.92% infected than small sized fish with low body weight. Present study addresses that Rhabdochona schizothoracis in the intestine and Diplozoon paradoxum in gills of snow trout fish has a long term relationship and call as a natural infection in cyprinids and it is zoonotic threat to human.

Resumo O peixe é a principal fonte de proteína de alta qualidade para mais de um bilhão de pessoas no mundo. Contudo, parasitas afetam diretamente a produtividade de peixes e, indiretamente, a saúde humana. Esta pesquisa teve como objetivo avaliar os parasitas helmintos em Schizothorax plagiostomus (truta da neve) do rio Panjkora, Khyber Pakhtunkhwa, Paquistão. Foram coletadas 88 amostras de peixes (n = 88) dos trechos alto, médio e baixo do rio por meio de redes de arrasto, redes de mão e varas de pesca. Todas as amostras de peixes coletadas foram examinadas no Laboratório de Parasitologia do Departamento de Zoologia, da Universidade de Malakand, quanto a parasitas helmintos durante o período de julho de 2018 a fevereiro de 2019. Entre esses peixes, nematódeos, trematódeos, cestóideos e acantocéfalos foram isolados e identificados. A prevalência geral de parasitas de peixes foi de 60,22% (53/88). A intensidade do parasita foi observada de 1,7 a 4,61%. A maior prevalência (86,36%) foi relatada no verão, enquanto a menor (36,36%), no inverno. Este estudo mostra que a temporada de verão afeta o ramo da pesca e resulta em carne de baixa qualidade, com risco de doenças zoonóticas. Os adultos foram altamente infectados (82,25%), enquanto nenhuma infecção foi encontrada em jovens. As amostras de peixes do sexo feminino apresentaram maior prevalência (68,22%) do que as do sexo masculino (48,22%). Os peixes coletados no trecho baixo do rio tiveram maior prevalência (60,22%) do que os do trecho alto (40%). Amostras de peixes com comprimento e peso máximos foram altamente infectadas (76,92%) do que peixes de pequeno porte e baixo peso corporal. O presente estudo aborda que Rhabdochona schizothoracis no intestino e Diplozoon paradoxum em brânquias de peixes de truta da neve possuem uma estreita relação que causa uma infecção natural em ciprinídeos, sendo uma ameaça zoonótica ao ser humano.

Evaluation of ecto and endo parasitic fauna of Schizothorax plagiostomus inhabitants of river Swat, Khyber PakhtunKhwa, Pakistan

Abstract Fish is consumed as a rich and cheaper source of white meat and proteins all over the world. Fish farming is the leading source of income generation throughout the world. The present research study was conducted with aims to investigate the ecto and endo parasitic fauna of S. plagiostomus (snow trout) in River Swat. A total of 96 fish samples were collected on monthly basis from July-2018 to February-2019, from upper, middle and lower reaches. Fish samples were collected with the help of cast net, hand net and fishing rods. Local fishermen and experts help were also sought out for fish collection. 61 out of 96 fishes were found infected by helminth parasites. The total prevalence and intensity of 63.54% and 2.90 was observed respectively during data analysis. Highest monthly prevalence of 83.33% was recorded during July and August, while lowest prevalence of 33.33% was noted during February. Five species of helminths parasites were detected from S. plagiostomus, of which two were trematodes (Rhabdochona shizothoracis and Rhabdochona species), one species of Monogenia (Diplozoon paraddoxum), one species of Cestodes (Nippotaenia species), and one species of Acanthocephalan (Neoechynorhynchus devdevi). Highest parasite wise prevalence, intensity and relative density of 21.87%, 4.09 and 0.895 was noted for R. schizothoracis while the lowest prevalence, intensity and relative density of 4.16%, 1.25 and 0.052 was noted for N. devdevi. Highest infection of 76.08% was observed in adults host while lowest, 40% infestation rate was observed in young fish samples. 73.68% prevalence was observed in female hosts while only 56.90% prevalence was observed in male individuals. Higher infection (83.33%) was noticed during summer season, while lowest infection (44.44%) was observed during winter season. Similarly 71.79% fishes were found infected that were collected from lower reaches of the River Swat than the fish samples collected from upper reaches (52%).

Resumo O peixe é consumido mundialmente por ser uma fonte rica e barata de carne branca e proteínas. A piscicultura é a principal fonte de geração de renda em todo o mundo. O presente estudo foi conduzido com o objetivo de investigar a fauna ecto e endoparasitária de S. plagiostomus (truta da neve) no rio Swat. Foram coletadas mensalmente 96 amostras de peixes, no período de julho de 2018 a fevereiro de 2019, nos trechos alto, médio e baixo com auxílio de redes de arrasto, redes de mão e varas de pesca. Pescadores locais e especialistas também ajudaram na coleta de peixes. Dos 96 peixes encontrados, 61 estavam infectados por parasitas helmintos. A prevalência de 63,54% e a intensidade total de 2,90 foram observadas durante a análise dos dados. A maior prevalência mensal de 83,33% foi registrada nos meses de julho e agosto, enquanto a menor, de 33,33%, em fevereiro. Cinco espécies de parasitas helmintos foram detectadas de S. plagiostomus, dos quais dois eram trematódeos (espécies Rhabdochona shizothoracis e Rhabdochona), uma espécie de monogenia (Diplozoon paradoxum), uma espécie de cestóideos (espécie Nippotaenia) e uma espécie de acantocéfalo (Neoechynorhynchus devdevi). As maiores prevalências de parasitas (21,87%), intensidade (4,09) e densidade relativa (0,895) foram observadas em R. schizothoracis, enquanto as menores prevalências de parasitas (4,16%), intensidade (1,25) e densidade relativa (0,052), em N. devdevi. A infecção mais alta (76,08%) foi constatada em adultos hospedeiros, ao passo que a taxa de infestação mais baixa (40%) foi encontrada em amostras de peixes jovens. A prevalência de 73,68% foi verificada em hospedeiros do sexo feminino, enquanto a de 56,90%, em indivíduos do sexo masculino. Maior infecção (83,33%) foi observada durante a temporada de verão, e a menor infecção (44,44%), durante o inverno. Da mesma forma, 71,79% dos peixes encontrados infectados foram coletados no trecho baixo do rio Swat, enquanto 52%, no trecho alto.