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1.
Vet Parasitol ; 151(2-4): 344-50, 2008 Feb 14.
Article in English | MEDLINE | ID: mdl-18065148

ABSTRACT

Control of Haemonchus placei, one of the most important cattle nematodes in Brazil, relies on the use of anthelmintics. However, there is a need for integrated control, which includes active immunization. The aim of this work was to assess the protection afforded to calves by immunization with adult H. placei extracts against a high-dose challenge infection, a condition frequently found in the tropics. Holstein calves aged 8-10 months were immunized four times with intestinal extracts (Group D) or with a Triton X-100-soluble fraction of adult H. placei (Group A), challenge-infected with 120,000 infective larvae and sacrificed 40 days later. Immunized animals had higher IgG titers than the controls against tested fractions after the 2nd immunization, peaking after the 4th. Sera from both immunized groups recognized bands of similar apparent mass in both antigenic preparations, some of which were similar in molecular weight to Haemonchus contortus antigens with known protective effect to sheep. Egg counts were 49% and 57% lower in Groups A and D than in controls, respectively. High levels of protection were observed in two of the four calves in Group D, as evidenced by very low worm numbers recovered at necropsy, absence of eggs in the uteri of the recovered females and reduced worm length. Group D animals also showed milder signs of anemia than the other infected animals. Results demonstrate that protection against homologous high-dose challenge can be achieved by immunizing calves with H. placei gut antigens.


Subject(s)
Antigens, Helminth/immunology , Cattle Diseases/prevention & control , Haemonchiasis/veterinary , Haemonchus/immunology , Immunization/veterinary , Animals , Antibodies, Helminth/blood , Antigens, Helminth/administration & dosage , Cattle , Cattle Diseases/parasitology , Female , Haemonchiasis/prevention & control , Haemonchus/chemistry , Immunoglobulin G/blood , Intestines/chemistry , Male , Membranes/chemistry , Parasite Egg Count/veterinary , Random Allocation , Time Factors
2.
Res Vet Sci ; 73(3): 297-306, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12443689

ABSTRACT

Activation-associated secreted proteins (ASP) of nematodes have been studied as potential vaccine components. In this study we report the cloning and analysis of cDNA and genomic sequences of Cooperia punctata and establish the presence of two 75% identical ASP-1 genes in C. punctata. Additional C. punctata ASP paralogues were shown to be present. Analysis of PCR products amplified from genomic DNA from a pool of worms revealed extensive sequence diversity within this family of proteins, reflecting the presence of different ASP paralogues in a single worm as well as extensive polymorphisms between different worms. ASP proteins contain a conserved region called the sperm-coating protein (SCP) domain of unknown function, which is present as a single copy in proteins from yeast and a wide range of multi-cellular organisms. Only in three nematodes has a protein composed of duplicated SCP-domains been identified. C. punctata is the first organism in which at least two such genes are found. Database searches identified similarity of the C-terminal cysteine-rich domain of ASP proteins to a nematode metallothionein motif. Cp-asp-1b was expressed in Escherichia coli and both the N-terminal and C-terminal domain were shown to be recognized by sera of C. punctata infected bovines. The description of the asp gene family of C. punctata provides the basis for more detailed studies into the extent of variation and immunological recognition of this family that may assist in rational vaccine design.


Subject(s)
Cattle Diseases/parasitology , Helminth Proteins/genetics , Trichostrongyloidea/genetics , Trichostrongyloidiasis/veterinary , Amino Acid Sequence , Animals , Base Sequence , Blotting, Western , Cattle , DNA, Complementary/genetics , Enzyme-Linked Immunosorbent Assay , Escherichia coli/genetics , Helminth Proteins/metabolism , Helminth Proteins/physiology , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , RNA, Helminth/genetics , RNA, Helminth/metabolism , Random Amplified Polymorphic DNA Technique , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Nucleic Acid , Trichostrongyloidea/metabolism , Trichostrongyloidea/physiology , Trichostrongyloidiasis/parasitology
3.
Vet Parasitol ; 108(4): 323-6, 2002 Oct 02.
Article in English | MEDLINE | ID: mdl-12354461

ABSTRACT

Undergraduate teaching of veterinary parasitology in South American countries is basically similar to most of the veterinary schools and offers lectures and practicals in parasitology (P) predominantly in the second year of the curriculum, and parasitic diseases (PD) in the third year, but in some schools also in the fourth and fifth years. However, there is a great variation in teaching hours allocated to P/PD between totals of about 50-169 h during the full curriculum. In addition to the lectures and practicals, schools are increasingly using tools (CD-ROMs) for self-instruction and new forms of education, such as workshops, round tables, and field practicals. The large number of important parasite species of large and small animals in tropical and subtropical areas would require additional hours for teaching--at least in some of the schools--considering the multidisciplinary characteristics of veterinary parasitology.


Subject(s)
Education, Veterinary , Parasitology/education , Teaching/methods , Animals , Brazil , Computer-Assisted Instruction/methods , Education, Veterinary/trends , Humans , Schools, Veterinary , South America
4.
Vet Parasitol ; 105(2): 131-8, 2002 Apr 30.
Article in English | MEDLINE | ID: mdl-11900927

ABSTRACT

Three groups of four calves each were trickle infected with three different levels of Cooperia punctata: 310 (group A), 1250 (group B) and 5000 (group C) third stage infective larvae (L3) twice a week over a 17-week period. Group D was the non-infected control group. Parasitological parameters as faecal egg counts (epg), worm burdens, size of worms and number of eggs per female were collected and the differences between the groups compared. Serological analyses were also conducted to investigate the efficiency of a recombinant C. oncophora CoES 14.2kDa protein in an ELISA to detect C. punctata antibodies. Group C had higher faecal egg counts until week 9 when the values decreased to those in group B. Mean faecal egg counts in group A were always lower than in the two other infected groups. The worm burdens were highest in group C, and lowest in group A, although the number of worms as a percentage of total larval intake was higher for the lower group. The mean length of the worms was shorter and the number of eggs per female lower for group C than for both other groups. ELISA using the CoES 14.2kDa proved to be efficient in measuring C. punctata antibodies. For group C it took 4 weeks to get increased levels of antibodies and this was one and 2 months more for groups B and A, respectively. Overall, there was a congruent relation between C. punctata antibodies and the cumulative exposure to the three different levels of trickle infections.


Subject(s)
Antibodies, Helminth/analysis , Cattle Diseases/parasitology , Helminth Proteins/immunology , Intestinal Diseases, Parasitic/veterinary , Trichostrongyloidea/growth & development , Trichostrongyloidiasis/veterinary , Animals , Antibodies, Helminth/biosynthesis , Cattle , Cattle Diseases/immunology , Enzyme-Linked Immunosorbent Assay/veterinary , Feces/parasitology , Female , Intestinal Diseases, Parasitic/parasitology , Larva , Molecular Weight , Parasite Egg Count/veterinary , Random Allocation , Recombinant Proteins/immunology , Trichostrongyloidiasis/parasitology
5.
Mem Inst Oswaldo Cruz ; 96(6): 861-4, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11562716

ABSTRACT

In vitro tests were carried out to verify the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Cooperia punctata, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to C. punctata, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species.


Subject(s)
Mitosporic Fungi/pathogenicity , Nematoda/microbiology , Pest Control, Biological , Animals , Cattle , Larva , Mitosporic Fungi/isolation & purification , Species Specificity
6.
Mem. Inst. Oswaldo Cruz ; 96(6): 861-864, Aug. 2001. graf, tab
Article in English | LILACS | ID: lil-298597

ABSTRACT

In vitro tests were carried out to verify the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Cooperia punctata, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to C. punctata, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species


Subject(s)
Animals , Cattle , In Vitro Techniques , Mitosporic Fungi/pathogenicity , Nematoda/microbiology , Larva , Mitosporic Fungi/isolation & purification , Pest Control, Biological
7.
Parasitology ; 123(Pt 6): 631-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11814050

ABSTRACT

A polymorphic set of 14 kDa excretory-secretory (E-S) antigen-encoding cDNAs, with similarity to a previously characterized 15 kDa E-S antigen of Haemonchus contortus, was cloned from Cooperia punctata. Five cDNAs encoding predicted proteins of 70-80% identity were sequenced. Genomic analyses of individuals proved the existence of three 14 kDa E-S antigen-encoding genes, excluding that the differences reflected polymorphisms between individuals in a population. Southern blots indicated the presence of additional members of this gene family. Thus, despite the fact that heterologously expressed C. punctata 14 kDa E-S products are shown to be recognized by immune sera, potential pitfalls in the development of a recombinant vaccine are presented by this genetic diversity. Vaccine design could be further rationalized by knowledge of the function, and possible redundancy in function, of the E-S products which is presently lacking. The limitations encountered in assigning a function to the 14/15 kDa family of E-S proteins that is thus far unique to the trichostrongyloid nematodes are discussed.


Subject(s)
Antigens, Helminth/genetics , Trichostrongyloidea/genetics , Amino Acid Sequence , Animals , Antigens, Helminth/chemistry , Base Sequence , Blotting, Southern/veterinary , Cattle , Cattle Diseases/immunology , Cattle Diseases/parasitology , Cattle Diseases/prevention & control , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Helminth/isolation & purification , Enzyme-Linked Immunosorbent Assay/veterinary , Escherichia coli/genetics , Gene Library , Genetic Variation , Immunoblotting/veterinary , Molecular Sequence Data , Recombinant Proteins , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Sequence Homology, Amino Acid , Trichostrongyloidea/chemistry , Trichostrongyloidea/immunology , Trichostrongyloidiasis/immunology , Trichostrongyloidiasis/prevention & control , Trichostrongyloidiasis/veterinary
8.
Mem. Inst. Oswaldo Cruz ; 95(6): 873-6, Nov.-Dec. 2000. tab, graf
Article in English | LILACS | ID: lil-273444

ABSTRACT

In vitro tests were carried out to assess the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Haemonchus placei, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to H. placei, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species


Subject(s)
Animals , Cattle , In Vitro Techniques , Mitosporic Fungi/pathogenicity , Nematoda/microbiology , Brazil , Haemonchus/microbiology , Mitosporic Fungi/isolation & purification , Predatory Behavior
9.
Mem Inst Oswaldo Cruz ; 95(6): 873-6, 2000.
Article in English | MEDLINE | ID: mdl-11080778

ABSTRACT

In vitro tests were carried out to assess the activity of 26 Brazilian isolates of predatory fungi of the genus Arthrobotrys on a free-living nematode (Panagrellus sp.) and on infective larvae of Haemonchus placei, a parasitic gastrointestinal nematode of cattle. The results showed that the free-living nematode Panagrellus sp. was the most preyed upon, compared to H. placei, for all the fungal treatments. Also, variable predatory capacity was observed for different fungal isolates belonging to the same genus when applied to different nematode species.


Subject(s)
Haemonchus , Mitosporic Fungi , Nematoda , Pest Control, Biological , Animals , Brazil , Cattle
10.
Vet Parasitol ; 87(4): 287-300, 2000 Feb 01.
Article in English | MEDLINE | ID: mdl-10669099

ABSTRACT

The dynamics of the humoral immune response of calves were analysed after primary infection and re-infection with the intestinal nematode Cooperia punctata. 12 male 5 month-old Holstein-Friesian calves were randomly divided into two groups A and B. At the beginning of the experiment Group A animals were each infected experimentally with a single oral dose of 130,000 infective third stage larvae (L3) of C. punctata. The animals of Group B were kept as non-infected controls. The two calves from Group A with the highest infections died of cooperiosis at 32 and 44 days after infection (DAI), respectively. On DAI 100 the calves were treated with the recommended dose of oxfendazole. On DAI 180 the remaining four calves of Group A and three animals of Group B (B1) were infected with 260,000 L3 of C. punctata, while the other three calves of Group B (B2) served as non-infected controls. Monitoring of the humoral immune response predominantly demonstrated an IgG1 response against both adult and L3 antigen of C. punctata. Moreover, re-infections increased the levels of these immunoglobulins. IgA levels were less increased than IgG1 and no significant increase was observed in IgG2 and IgM levels. Immunoblotting analysis showed that total IgG present in the serum of the primary infected animals mainly reacted against adult proteins of 12-14 and 17-20 kDa and against L3 proteins of 33 and 43 kDa. After re-infection total IgG reacted with the same adult proteins but also with an adult 29 kDa protein.


Subject(s)
Antibodies, Helminth/biosynthesis , Cattle Diseases/immunology , Trichostrongyloidiasis/veterinary , Animals , Cattle , Electrophoresis, Polyacrylamide Gel/veterinary , Enzyme-Linked Immunosorbent Assay/veterinary , Feces/parasitology , Male , Parasite Egg Count/veterinary , Random Allocation , Recurrence , Trichostrongyloidiasis/immunology
11.
Arq. bras. med. vet. zootec ; 49(3): 279-90, jun. 1997. ilus
Article in Portuguese | LILACS | ID: lil-264488

ABSTRACT

Dois grupos de cinco bezerros, das raças Holandesa e Nelore, com idade aproximada de nove meses, receberam por via oral uma dose única de 1.000 larvas infectantes (L3) por kg de peso corporal de Haemonchus placei. Os animais foram mantidos sob observaçäo clínica após a infecçäo. Amostras de sangue foram coletadas semanalmente por punçäo venosa, desde uma semana antes, até a oitava semana pós-infecçäo. Os estudos hematológicos abrangeram hematócrito, contagem diferencial de leucócitos, determinaçöes de hemoglobina, fibrinogênio e proteínas plasmáticas. Os exames parasitológicos compreenderam exames de fezes semanais com contagem de ovos (OPG) e estimativa de cargas de vermes na necropsia. Amostras de tecido da mucosa do abomaso foram submetidos a estudos histopatológicos. Ambos os grupos mostraram números crescentes de OPG após a quinta semana, sendo que os bezerros de raça Holandesa apresentaram maiores contagens do que os da raça Nelore. Na terceira semana pós-infecçäo e até o final do experimento, os bezerros da raça Holandesa tiveram anemia e hipoproteinemia, enquanto que os bezerros Nelore näo apresentaram alteraçöes significativas desses parâmetros. A necropsia, os bezerros da raça Holandesa apresentaram uma carga de vermes significativamente maior dos que os da raça Nelore. As alteraçöes patológicas visíveis e lesöes histopatológicas foram similares, embora macroscopicamente fossem levemente mais evidentes na raça Holandesa. Estes resultados demonstram que bezerros da raça Holandesa säo mais susceptíveis à infecçäo e aos efeitos patogênicos de H. placei do que bezerros da raça Nelore


Subject(s)
Animals , Cattle , Haemonchus , Helminths
12.
Am J Trop Med Hyg ; 35(3): 575-8, 1986 May.
Article in English | MEDLINE | ID: mdl-3706624

ABSTRACT

A 14-year-old boy with a tetralogy of Fallot showed a subacute, progressive encephalopathy characterized by headache, stupor and coma. Death occurred three months after the beginning of the illness. Neuropathologic examination revealed diffuse foci of necrosis of the cerebral hemispheres and cerebellum, and the presence of the nematode Lagochilascaris minor in the parenchyma and in the cisterns at the base of the brain. In almost all 28 cases of human lagochilascaris previously reported, the worms were located in the soft tissues of the neck and throat, tonsils, mastoids and paranasal sinuses. This is the first reported case in which Lagochilascaris infected the brain. Since the life cycle of the worm is unknown the pathogenesis of the central nervous system lesions is obscure.


Subject(s)
Ascaridoidea , Brain Diseases/parasitology , Brain/parasitology , Nematode Infections/parasitology , Adolescent , Ascaridoidea/anatomy & histology , Ascaridoidea/growth & development , Brain/pathology , Brain Diseases/complications , Brain Diseases/pathology , Humans , Male , Nematode Infections/complications , Nematode Infections/pathology , Tetralogy of Fallot/complications
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