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This study evaluated the efficacy of albendazole, ivermectin, levamisole, mebendazole and praziquantel on monogeneans of Colossoma macropomum, based on in vitro and in vivo assays. In vitro assays indicated that albendazole (500, 100, 1,500 and 2,000 mg/L), ivermectin (200, 250, 300 and 350 mg/L) and levamisole (50, 75, 100 and 125 mg/L) were 100% effective against Anacanthorus spatulatus, Notozothecium janauachensis, Mymarothecium boegeri and Linguadactyloides brinkmanni, while mebendazole (125, 150, 175 and 200 mg/L) and praziquantel (5, 10, 15 and 20 mg/L) were ineffective. Fish mortality in 24 hr therapeutic baths with 500 mg/L of albendazole was 6.6%, but the behaviour of the animals remained unchanged, while 200 mg/L of ivermectin caused lethargy, signs of hypoxia and 100% mortality within 2 hr, and 125 mg/L of levamisole caused no mortality. The efficacy of 500 mg/L of albendazole was 48.6% in the 24 hr baths, while that of 125 mg/L levamisole was 88.2%. Although ivermectin showed in vitro efficacy, the lowest concentration used in baths was highly toxic to fish. Therefore, we recommend the use of 125 mg/L of levamisole to control and treat monogenean infestations on C. macropomum in fish farming. Made available in DSpace on 2019-02-13T23:42:26Z (GMT). No. of bitstreams: 1 CPAFAP2019Albendazolelevamisole.pdf: 565734 bytes, checksum: d31ab5323d605a8330e2f46de6b2e702 (MD5) Previous issue date: 2019-02-13

The present investigation evaluated the influence of seasonality and locality on the structure of the parasite community of the catfish Pimelodus blochii. A total of 160 fish were collected from two rivers in the State of Acre, western Brazilian Amazon: 80 fish in River Acre and 80 in River Iaco, with 40 in each season (rainy and drought). The overall prevalence was 78.7% and 1461 parasite specimens (adults and larvae) were allocated in 22 taxa: 5 of Monogenea, 10 of Nematoda, 3 of Digenea, 1 of Cestoda and 3 of Crustacea. In drought season, Procamallanus (Spirocamallanus) pimelodus and Demidospermus peruvianus were more prevalent in River Acre and Iaco, respectively. The parasite diversity (Brillouin index) as well as the prevalence and abundance of the monogeneans D. peruvianus, D. striatus, Demidospermus sp. and Ameloblastella sp. were higher in River Acre. The parasite community structure were dissimilar among rivers, and seasonally in River Iaco. These results suggest that environmental traits may overshadow seasonal influences on the parasite community structure, which may be related to the higher anthropization in River Acre. Furthermore, seasonality exerted less influence on the parasite community than expected, probably because the two rivers have different hydrological traits than those of other rivers in the Brazilian Amazon. New host and locality records expanded our knowledge of parasite biodiversity of P. blochii. Made available in DSpace on 2018-11-25T23:36:50Z (GMT). No. of bitstreams: 1 CPAFAP2018Communitystructureofmetazoanparasite.pdf: 1020163 bytes, checksum: 71f7901192d4cf1303b45eb0f06800e7 (MD5) Previous issue date: 2018-11-23

Studies on parasites of wild fish populations are important for knowledge of biodiversity, since parasites represent a great fraction of the planet?s biodiversity. The present study investigated the helminths fauna of Leporinus friderici, Mylossoma duriventre, Hoplerythrinus unitaeniatus and Osteoglossum bicirrhosum collected from the lower Jari River, in the state of Amapá in the eastern Amazon region, Brazil. These fish, which have varying eating habits, were caught using gill nets with different mesh sizes for analysis of helminths, using standard methodologies. The helminths collected from these hosts were: Procamallanus (Spirocamallnus) inopinatus, Guyanema seriei seriei, Contracaecum sp., Eustrongylides sp. (Nematoda), Clinostomum marginatum, Dadaytrema oxycephala, Caballerotrema aruanense, Posthodiplostomum sp. (Digenea), Quadrigyrus nickoli and Neoechinorhynchus sp. (Acanthocephala). Hoplerythrinus unitaeniatus presented the highest prevalence, intensity and mean abundance of C. marginatum, while M. duriventre was the host with lowest level of this parasite. The greatest diversity was of Contracaecum sp., sole helminth found in all species of fish studied. The presence of larvae of endoparasites indicates that these fish are intermediate hosts in the Jari River basin. Made available in DSpace on 2019-02-12T23:49:39Z (GMT). No. of bitstreams: 1 CPAFAP2019Helminthicendofaunaoffourspecies.pdf: 909329 bytes, checksum: 9e4a7a1de70a0b0e4fb798a8795ce2b2 (MD5) Previous issue date: 2019-02-12 e.393

This study has investigated the influence of unilateral eyestalk ablation on the survival, molting frequency, fecundity, reproductive output, and fertility of M. amazonicum females. We divided 96 females into with ablation and without ablation groups with six replicates. Water quality, growth, survival rate, intermolt period, molts number, and ovigerous females over a 90-day period were monitored. Unilateral eyestalk ablation reduced intermolt period by 30% and increased molts number, ovigerous females, and reproductive output. Our findings indicate that unilateral eyestalk ablation positively influences reproduction in M. amazonicum and is appropriate for females of this species having a body length of greater than or equal to 70 mm. Made available in DSpace on 2019-02-12T23:48:30Z (GMT). No. of bitstreams: 1 CPAFAP2019Unilateraleyestalkablationimproves.pdf: 2207733 bytes, checksum: 83d955bbd8779994deb13b0eaf25c605 (MD5) Previous issue date: 2019-02-12

The current study tested the efficacy of a dietary immunostimulant additive (Aquate Fish?®) on the growth performance, and on the physiological and immune responses of Arapaima gigas. Two trials were carried out: a feeding trial for 30 days with the experimental diets and a challenge trial for 7 days, in which fish were bacterial challenge (Aeromonas hydrophila) following by 60 s handling stress. During the feeding trial, fingerlings were fed diets supplemented with 0 (control), 6, 9 and 12 g Aquate Fish?®/kg diet. Dietary supplementation did not influence feed intake, feed conversion and condition factor, but increased the final biomass, number of erythrocytes, thrombocytes, leukocytes, lymphocytes, monocytes, hemoglobin, glucose, globulins and plasma triglycerides in fish fed at a concentration of 12 g/kg diet. After bacterial infection, mortality occurred only in fish fed control treatment, whereas respiratory burst of leukocytes, number of leukocytes and lymphocytes increased in fish that received 12 g of dietary supplementation. The results indicated that dietary supplementation with 12 g of Aquate Fish?® improved biomass and immunity performance of A. gigas fingerlings, without negatively affecting blood biochemical parameters. Made available in DSpace on 2019-09-10T00:56:00Z (GMT). No. of bitstreams: 1 CPAFAP2019Growthphysiologicalandimmune.pdf: 184829 bytes, checksum: d15cf60e4f16da2c64a7003e57d1da27 (MD5) Previous issue date: 2019

The present study investigated the occurrence of metacercariae of Ithyoclinostomum dimorphum in Hoplias malabaricus in the basin of the São Francisco River in the state of Minas Gerais (Brazil). Twenty-nine fi sh were examined in June 2012 during a survey of fi sh and parasitic fauna. Of the fish examined, 34.5 % had infected eyes, intestine and musculature, with a mean intensity of 1.1 and an abundance of 0.4 per fi sh. The prevalence in the intestine was 31.0 %, with mean intensity of 1.1 and mean abundance of 0.3. In the eyes, the prevalence was 3.4 %, with a mean intensity of 1.0 and mean abundance of 1.0. The metacercaria found in the right eyeball was lodged between the cornea and iris. The low parasitism did not affect the condition factor (Kn) of the parasitized fi sh. This was the fi rst report of I. dimorphum in the eyes of Hoplias malabaricus, a secondary intermediate host for this endoparasite. Made available in DSpace on 2019-01-12T23:29:19Z (GMT). No. of bitstreams: 1 CPAFAP2018Ithyoclinostomusdimorphum.pdf: 1633845 bytes, checksum: 4b5a2f8169a7b4e7121ba98b6e36fbec (MD5) Previous issue date: 2019-01-10