Prevalence of Eimeria spp. in calves from dairy farms in northern Paraná state, Brazil

Prevalência de Eimeria spp. em bezerros de propriedades leiteiras do norte do estado do Paraná, Brasil

Sérgio Tosi Cardim Mércia Seixas Victor Bittencourt Dutra Tabacow Alessandra Taroda Priscilla Gomes Carneiro Thais Agostinho Martins Luiz Daniel de Barros Ana Flávia Minutti Andreas Lazaros Chryssafidis Odilon Vidotto João Luis Garcia About the authors

Abstract

Bovine coccidiosis is a disease of major importance in cattle herds across the world. The disorder mainly affects young calves, and E. bovis and E. zuernii are considered the most pathogenic species of the genus, however, E. alabamensis have been described in grazing calves. In this study, the prevalence of Eimeria spp. was evaluated in calves on dairy farms in the northern region of the state of Paraná, Brazil. Four hundred calves on 44 dairy farms were tested for the presence of coccidian oocysts. The positives were re-examined and the oocysts were morphometrically analyzed for species identification. All the farms were contaminated and 205 animals (51.25%) presented Eimeria spp. oocysts. Among these, 146 animals (71.22%) were co-infected by two or more species of coccidia. Ten species of Eimeria were identified: E. bovis (in 30.25% of the positive samples), E. alabamensis (26.75%), E. zuernii (22.00%), E. ellipsoidalis (18.50%), E. auburnensis (13.75%), E. canadensis (8.00%), E. cylindrica (7.25%), E. subspherica (5.00%), E. bukidnonensis (3.00%) and E. brasiliensis (0.75%). This study demonstrates the high prevalence of Eimeria spp. in the northern region of Paraná, Brazil, and detection for the first time in our region the pathogenic species E. alabamensis.

Keywords:
Coccidiosis; bovine; epidemiology; morphometric; oocysts

Resumo

A coccidiose bovina é uma doença de grande importância em rebanhos ao redor do mundo. A desordem afeta principalmente bezerros jovens, e E. bovis e E. zuernii consideradas as espécies mais patogênicas deste gênero, causando grave enterite em animais infectados. No entanto, casos de E. alabamensis foram descritos em bezerros mantidos a pasto. No presente estudo, a prevalência de Eimeria spp. foi avaliada em bezerros de gado leiteiro da região norte do estado do Paraná, Brasil. Quatrocentos bezerros foram amostrados e testados para a presença de oocistos de coccídios. Os positivos foram re-examinados e os oocistos analisados morfologicamente para identificação da espécie. Todas as fazendas estavam contaminadas e 205 (51,25%) animais apresentaram oocistos de Eimeria spp. Destes, 146 (71,22%) animais estava co-infectados por duas ou mais espécies de coccídio. Dez espécies de Eimeria foram identificadas: E. bovis (30,25% de amostras positivas), E. alabamensis (26,75%), E. zuernii (22,00%), E. ellipsoidalis (18,50%), E. auburnensis (13,75%), E. canadensis (8,10%), E. cylindrica (8,00%), E. subspherica (5,00%), E. bukidnonensis (3,00%) e E. brasiliensis (0,75%). Este estudo demonstra a alta prevalência de Eimeria spp. na região norte do estado do Paraná, Brasil, e a detecção, pela primeira vez, de E. alabamensis.

Palavras-chave:
Coccidiose; bovinos; epidemiologia; morfometria; oocistos

Introduction

Eimeriosis is caused by protozoa of the phylum Apicomplexa, family Eimeriidae and genus Eimeria (BRUHN et al., 2011Bruhn FRP, Lopes MA, Demeu FA, Perazza CA, Pedrosa MF, Guimarães AM. Frequency of species of Eimeria in females of the Holstein-Friesian breed at the post-weaning stage during autumn and winter. Rev Bras Parasitol Vet 2011; 20(4): 303-307. PMid:22166384. http://dx.doi.org/10.1590/S1984-29612011000400008.
http://dx.doi.org/10.1590/S1984-29612011...
). This disease is one of the most common parasitoses in cattle around the world, and it is especially important in animals less than one year old (DAUGSCHIES et al., 2004Daugschies A, Imarom S, Ganter M, Bollwahn W. Prevalence of Eimeria spp. in sows at piglet-producing farms in Germany. J Vet Med B Infect Dis Vet Public Health 2004; 51(3): 135-139. PMid:15107040. http://dx.doi.org/10.1111/j.1439-0450.2004.00734.x.
http://dx.doi.org/10.1111/j.1439-0450.20...
, BRUHN et al., 2011Bruhn FRP, Lopes MA, Demeu FA, Perazza CA, Pedrosa MF, Guimarães AM. Frequency of species of Eimeria in females of the Holstein-Friesian breed at the post-weaning stage during autumn and winter. Rev Bras Parasitol Vet 2011; 20(4): 303-307. PMid:22166384. http://dx.doi.org/10.1590/S1984-29612011000400008.
http://dx.doi.org/10.1590/S1984-29612011...
).

During its life cycle, the parasite destroys the host’s enterocytes, causing loss of blood, water, albumin and electrolytes to the intestinal lumen. These effects may lead to diarrhea, dehydration, prostration and eventually death, depending on the period of exposure and infective dose (JONSSON et al., 2011Jonsson NN, Piper EK, Gray CP, Deniz A, Constantinoiu CC. Efficacy of toltrazuril 5% suspension against Eimeria bovis and Eimeria zuernii in Calves and Observations on the Associated Immunopathology. Parasitol Res 2011;109(Suppl S1): S113-S128. PMid:21739381. http://dx.doi.org/10.1007/s00436-011-2408-2.
http://dx.doi.org/10.1007/s00436-011-240...
; ALMEIDA et al., 2011Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
).

Among a fourteen known pathogenic species, E. bovis and E. zuernii are considered to be the most important, due to the severity of clinical cases caused in younger animals (JONSSON et al., 2011Jonsson NN, Piper EK, Gray CP, Deniz A, Constantinoiu CC. Efficacy of toltrazuril 5% suspension against Eimeria bovis and Eimeria zuernii in Calves and Observations on the Associated Immunopathology. Parasitol Res 2011;109(Suppl S1): S113-S128. PMid:21739381. http://dx.doi.org/10.1007/s00436-011-2408-2.
http://dx.doi.org/10.1007/s00436-011-240...
; BANGOURA et al., 2011Bangoura B, Mundt HC, Schmäschke R, Westphal B, Daugschies A. Prevalence of Eimeria bovis and Eimeria zuernii in German Cattle herds and factors influencing oocyst excretion. Parasitol Res 2011;109(Suppl 1): 129-138. PMid:21739382. http://dx.doi.org/10.1007/s00436-011-2409-1.
http://dx.doi.org/10.1007/s00436-011-240...
; FLORIÃO et al., 2016Florião MM, Lopes BB, Berto BP, Lopes CWG. New approaches for morphological diagnosis of bovine Eimeria species: a study on a subtropical organic dairy farm in Brazil. Trop Anim Health Prod 2016; 48(3): 577-584. PMid:26873157. http://dx.doi.org/10.1007/s11250-016-0998-5.
http://dx.doi.org/10.1007/s11250-016-099...
). However, some authors have emphasized the importance of E. alabamensis as the causative agent of coccidiosis in animals feeding on pastures (SVENSSON et al., 1993Svensson C, Hooshmand-Rad P, Pehrson B, Törnquist M, Uggla A. Excretion of Eimeria oocysts in calves during their first three weeks after turn-out to pasture. Acta Vet Scand 1993; 34(2): 175-182. PMid:8266895., 1994Svensson C, Uggla A, Pehrson B. Eimeria alabamensis infection as a cause of diarrhoea in calves at pasture. Vet Parasitol 1994; 53(1-2): 33-43. PMid:8091616. http://dx.doi.org/10.1016/0304-4017(94)90014-0.
http://dx.doi.org/10.1016/0304-4017(94)9...
; MARSHALL et al., 1998Marshall RN, Catchpole J, Green JA, Webster KA. Bovine coccidiosis in calves following turnout. Vet Rec 1998; 143(13): 366-367. PMid:9800306. http://dx.doi.org/10.1136/vr.143.13.366.
http://dx.doi.org/10.1136/vr.143.13.366...
; SVENSSON, 2000Svensson C. Excretion of Eimeria alabamensis oocysts in grazing calves and young stock. J Vet Med B Infect Dis Vet Public Health 2000; 47(2): 105-110. PMid:10763379. http://dx.doi.org/10.1046/j.1439-0450.2000.00324.x.
http://dx.doi.org/10.1046/j.1439-0450.20...
).

This disease is responsible for major economic losses. An impact of US$ 400 million on the American market has been estimated, due to clinical cases alone, while over US$ 3.8 million are lost through treatments for bovine coccidiosis in Canada (MATJILA & PENZHORN, 2002Matjila PT, Penzhorn BL. Occurrence and diversity of bovine coccidia at three localities in South Africa. Vet Parasitol 2002; 104(2): 93-102. PMid:11809329. http://dx.doi.org/10.1016/S0304-4017(01)00605-7.
http://dx.doi.org/10.1016/S0304-4017(01)...
; REHMAN et al., 2011Rehman TU, Khan MN, Sajid MS, Abbas RZ, Arshad M, Iqbal Z, et al. Epidemiology of Eimeria and associated risk factors in cattle of district Toba Tek Singh, Pakistan. Parasitol Res 2011; 108(5): 1171-1177. PMid:21110042. http://dx.doi.org/10.1007/s00436-010-2159-5.
http://dx.doi.org/10.1007/s00436-010-215...
).

The rate of occurrence of Eimeria spp. is highly variable, with prevalence rates ranging from 10 to 100% among animals tested in Europe and different regions in Brazil (LENTZE et al., 1999Lentze T, Hofer D, Gottstein B, Gaillard C, Busato A. Prevalence and importance of endoparasites in calves raised in Swiss cow-calf farms. Dtsch Tierarztl Wochenschr 1999; 106(7): 275-281. PMid:10481370., STEWART et al., 2008Stewart ID, Smith RP, Ellis-Iversen J. Eimeria species in cattle on farms in England and Wales. Vet Rec 2008; 162(15): 482-483. PMid:18408197. http://dx.doi.org/10.1136/vr.162.15.482.
http://dx.doi.org/10.1136/vr.162.15.482...
, ALMEIDA et al., 2011Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
, BRUHN et al., 2011Bruhn FRP, Lopes MA, Demeu FA, Perazza CA, Pedrosa MF, Guimarães AM. Frequency of species of Eimeria in females of the Holstein-Friesian breed at the post-weaning stage during autumn and winter. Rev Bras Parasitol Vet 2011; 20(4): 303-307. PMid:22166384. http://dx.doi.org/10.1590/S1984-29612011000400008.
http://dx.doi.org/10.1590/S1984-29612011...
, 2012Bruhn FRP, Silva FA Jr, Carvalho AHO, Orlando DR, Rocha CMBM, Guimarães AM. Occurrences of Eimeria spp. and gastrointestinal nematodes in dairy calves in southern Minas Gerais, Brazil. Rev Bras Parasitol Vet 2012; 21(2): 171-175. PMid:22832761. http://dx.doi.org/10.1590/S1984-29612012000200019.
http://dx.doi.org/10.1590/S1984-29612012...
; KOUTNY et al., 2012Koutny H, Joachim A, Tichy A, Baumgartner W. Bovine Eimeria species in Austria. Parasitol Res 2012; 110(5): 1893-1901. PMid:22167365. http://dx.doi.org/10.1007/s00436-011-2715-7.
http://dx.doi.org/10.1007/s00436-011-271...
). There are just two works concerning about eimeriosis in cattle from south Brazil, both were conducted in Paraná state (GUIMARÃES et al., 1995Guimarães JS Jr, Amaral CHS, Carvalho MCM, Pereira ABL. Eimeria spp. (Apicomplexa: Eimeriidae) em bezerros da raça holandesa no norte do Paraná e sudoeste de São Paulo, Brasil. Rev Bras Parasitol Vet 1995; 4(2): 71.; HILLESHEIM & FREITAS, 2016Hillesheim LO, Freitas FLC. Ocorrência de eimeriose em bezerros criados em propriedades de agricultura familiar – nota científica. Ciênc Anim Bras 2016; 17(3): 472-481. http://dx.doi.org/10.1590/1089-6891v17i333327.
http://dx.doi.org/10.1590/1089-6891v17i3...
), the first one observed 16.7% of Eimeria spp. positivity at northern (GUIMARÃES et al., 1995Guimarães JS Jr, Amaral CHS, Carvalho MCM, Pereira ABL. Eimeria spp. (Apicomplexa: Eimeriidae) em bezerros da raça holandesa no norte do Paraná e sudoeste de São Paulo, Brasil. Rev Bras Parasitol Vet 1995; 4(2): 71.), and the second one 48.2% of Eimeria spp. positivity at southwestern (HILLESHEIM & FREITAS, 2016Hillesheim LO, Freitas FLC. Ocorrência de eimeriose em bezerros criados em propriedades de agricultura familiar – nota científica. Ciênc Anim Bras 2016; 17(3): 472-481. http://dx.doi.org/10.1590/1089-6891v17i333327.
http://dx.doi.org/10.1590/1089-6891v17i3...
). Thus, the objectives of the present study were to determine the prevalence of Eimeria spp. among dairy calves, in herds in the northern region of the state of Paraná, Brazil. This information is relevant because it forms a preliminary stage in devising control schemes against these parasites in dairy herds.

Materials and Methods

Samples

In the present work, a cross-sectional epidemiological study was performed, and four hundred male and female calves, holstein and jersey breed, aged between 20 days and 12 months, on 44 different farms in the northern region of the state of Paraná, Brazil, were sampled. The samples were collected from February 2012 to October 2013. The animals were selected randomly and around 10 animals were included per farm. Feces were collected directly from the rectal ampulla of each animal. All procedures performed in the present study were approved by the Animal Ethics Committee of the State University of Londrina (CEEA/UEL N. 121/2013). The sample size (384) was calculated assuming a prevalence of 50% with a confidence level of 95% and efficacy of 5% by Epi Info 3.5.4. The number of farms was chosen according to convenience, but it fulfilled the minimum sample size that had previously been calculated.

Study area

The climate of northern region of the state of Paraná is characterized as mesothermal with hot summers, infrequent hoar-frosts, and rains with tendency of concentration in the summer months. It presents the following annual averages: temperature of warmer months exceeding 22°C, and of colder months below 18°C; rainfall between 1,300 and 1,700 mm; and a relative humidity of 75%, without water deficiency (IPARDES, 2004Instituto Paranaense de Desenvolvimento Econômico e Social – IPARDES. Leituras regionais: Mesorregião Geográfica Norte Central Paranaense. Curitiba: IPARDES/BRDE; 2004.). A map with all cities were samples were collected is showed in Figure 1.

Figure 1
Map of Paraná state, Brazil showing municipalities where calf feces samples were collected in for Eimeria spp. occurrence, in the years 2012 and 2013.

Coprological examination and morphological identification

The samples were examined for the presence and number of oocysts per gram of feces (OOPG) using saturated NaCl solution and MacMaster chambers (modified from Gordon & Whitlock, as described in UENO & GONÇALVES, 1998Ueno H, Gonçalves PC. Manual para diagnóstico das helmintoses de ruminantes. 4th ed. Tokio: Japan International Cooperation Agency; 1998.). Positive samples were re-submitted to the flotation technique and oocysts were collected on coverslips, which were observed under an optical microscope for morphological evaluation (modified from Willis & Molay, as described in UENO & GONÇALVES, 1998Ueno H, Gonçalves PC. Manual para diagnóstico das helmintoses de ruminantes. 4th ed. Tokio: Japan International Cooperation Agency; 1998.). Fifty oocysts per sample were analyzed for size, presence of micropyle and wall conformation (REHMAN et al., 2011Rehman TU, Khan MN, Sajid MS, Abbas RZ, Arshad M, Iqbal Z, et al. Epidemiology of Eimeria and associated risk factors in cattle of district Toba Tek Singh, Pakistan. Parasitol Res 2011; 108(5): 1171-1177. PMid:21110042. http://dx.doi.org/10.1007/s00436-010-2159-5.
http://dx.doi.org/10.1007/s00436-010-215...
). The examination was carried out using a B1 microscope (Motic, China), under 400x magnification, with a TK-C138 camera (JVC, Japan) attached to the microscope for documenting Eimeria spp. found in the samples (CORNELISSEN et al., 1995Cornelissen AWCA, Verstegen R, Van Den Brand H, Perie NM, Eysker M, Lam TJGM, et al. An observational study of Eimeria species in housed cattle on Dutch dairy farms. Vet Parasitol 1995; 56(1-3): 7-16. PMid:7732653. http://dx.doi.org/10.1016/0304-4017(94)00671-X.
http://dx.doi.org/10.1016/0304-4017(94)0...
; REHMAN et al., 2011Rehman TU, Khan MN, Sajid MS, Abbas RZ, Arshad M, Iqbal Z, et al. Epidemiology of Eimeria and associated risk factors in cattle of district Toba Tek Singh, Pakistan. Parasitol Res 2011; 108(5): 1171-1177. PMid:21110042. http://dx.doi.org/10.1007/s00436-010-2159-5.
http://dx.doi.org/10.1007/s00436-010-215...
; BANGOURA et al., 2011Bangoura B, Mundt HC, Schmäschke R, Westphal B, Daugschies A. Prevalence of Eimeria bovis and Eimeria zuernii in German Cattle herds and factors influencing oocyst excretion. Parasitol Res 2011;109(Suppl 1): 129-138. PMid:21739382. http://dx.doi.org/10.1007/s00436-011-2409-1.
http://dx.doi.org/10.1007/s00436-011-240...
). Eimeria spp. unsporulated oocysts were identified in accordance with parameters described by Levine (1961)Levine ND. Protozoan parasites of domestic animals and of man. Minneapolis: Burgess Publishing Company; 1961., and Eckert et al. (1995)Eckert J, Taylor M, Catchpole J, Licois D, Coudert P, Bucklar H. Morphological characteristics of oocysts. In: Eckert J, Braun R, Shirley MW, Coudert P. Biotechnology guidelines on techniques in coccidiosis research. Luxembourg: European Commission; 1995. p. 103-119..

Statistical analysis

The descriptive analysis were performed by the use of Excel software package. For prevalence, and confidence interval at 95% from apparent prevalence OpenEpi version 3.01 was used.

Results and Discussion

Eimeria spp. parasites were widespread and very common in the cattle herds included in this study. From the 400 samples analyzed, 205 (51.25%) were positive to Eimeria spp.. Within the positives, 146 (71.22%) were cross infected with multiple Eimeria spp. and 59 (28.78%) presented only one species of this parasite genus. The oocyst counts ranged from 50 to 207,800 OOPG and 10 different species were identified by morphological examination (Table 1). The identification of parasitic species, the prevalence of infection in animals and farms and morphometric measurements of analyzed specimens are presented in Table 1.

Table 1
Identification of Eimeria spp. in dairy calf feces from the northern region of the state of Paraná, Brazil, collected in the years 2012 and 2013. The results of prevalence in samples, farms and their respective morphometry.

The mean of prevalence in the herds observed here was 56.8% (CI95% = 48.66-64.95). Investigations carried out in different regions of Brazil and around the world have found variable prevalence of Eimeria spp. in cattle in dairy and beef herds (CORNELISSEN et al., 1995Cornelissen AWCA, Verstegen R, Van Den Brand H, Perie NM, Eysker M, Lam TJGM, et al. An observational study of Eimeria species in housed cattle on Dutch dairy farms. Vet Parasitol 1995; 56(1-3): 7-16. PMid:7732653. http://dx.doi.org/10.1016/0304-4017(94)00671-X.
http://dx.doi.org/10.1016/0304-4017(94)0...
; CHIBUNDA et al., 1997Chibunda RT, Muhairwa AP, Kambarage DM, Mtambo MMA, Kusiluka LJM, Kazwala RR. Eimeriosis in dairy cattle farms in Morogoro municipality of Tanzania. Prev Vet Med 1997; 31(3-4): 191-197. PMid:9234443. http://dx.doi.org/10.1016/S0167-5877(96)01131-2.
http://dx.doi.org/10.1016/S0167-5877(96)...
; REBOUÇAS et al., 1994Rebouças MM, Grasso LMPS, Spósito Filha E, Amaral V, Santos SM, Silva DM. Prevalência e distribuição de protozoários do gênero Eimeria (Apicomplexa: Eimeriidae) em bovinos nos municípios de Altinópolis, Taquaritinga, São Carlos e Guaíra – Estado de São Paulo, Brasil. Rev Bras Parasitol Vet 1994; 3(2): 125-130.; SÁNCHEZ et al., 2008Sánchez RO, Romero JR, Founroge RD. Dynamics of Eimeria oocyst excretion in dairy calves in the Province of Buenos Aires (Argentina), during their first 2 months of age. Vet Parasitol 2008; 151(2-4): 133-138. PMid:18096320. http://dx.doi.org/10.1016/j.vetpar.2007.11.003.
http://dx.doi.org/10.1016/j.vetpar.2007....
; ALMEIDA et al., 2011Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
; REHMAN et al., 2011Rehman TU, Khan MN, Sajid MS, Abbas RZ, Arshad M, Iqbal Z, et al. Epidemiology of Eimeria and associated risk factors in cattle of district Toba Tek Singh, Pakistan. Parasitol Res 2011; 108(5): 1171-1177. PMid:21110042. http://dx.doi.org/10.1007/s00436-010-2159-5.
http://dx.doi.org/10.1007/s00436-010-215...
; BANGOURA et al., 2011Bangoura B, Mundt HC, Schmäschke R, Westphal B, Daugschies A. Prevalence of Eimeria bovis and Eimeria zuernii in German Cattle herds and factors influencing oocyst excretion. Parasitol Res 2011;109(Suppl 1): 129-138. PMid:21739382. http://dx.doi.org/10.1007/s00436-011-2409-1.
http://dx.doi.org/10.1007/s00436-011-240...
; DONG et al., 2012Dong H, Zhao Q, Han H, Jiang L, Zhu S, Li T, et al. Prevalence of coccidial infection in dairy cattle in Shanghai, China. J Parasitol 2012; 98(5): 963-966. PMid:22590990. http://dx.doi.org/10.1645/GE-2966.1.
http://dx.doi.org/10.1645/GE-2966.1...
; ENEMARK et al., 2013Enemark HL, Dahl J, Enemark JMD. Eimeriosis in Danish dairy calves – correlation between species, oocyst excretion and diarrhoea. Parasitol Res 2013;112(Suppl S1): 169-176. PMid:23765344. http://dx.doi.org/10.1007/s00436-013-3441-0.
http://dx.doi.org/10.1007/s00436-013-344...
). Almeida et al. (2011)Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
found that the prevalence of Eimeria spp. contamination among young and adult cattle on dairy farms in the northeast of the state of Bahia, Brazil, was 33.33%. However, the prevalence of this parasite among calves younger than one year of age was 51.22%, which was very similar to the prevalence found in the present study.

One of the problems for the diagnosis of eimeriosis is the fact that it takes several days to sporulated oocysts for photomicrography what is time consuming. Here in the present study, we focused on epidemiological study, by using a faster approach instead time consuming one such as: sporulation and photomicrography. For this, we followed methodology described by Cornelissen et al. (1995)Cornelissen AWCA, Verstegen R, Van Den Brand H, Perie NM, Eysker M, Lam TJGM, et al. An observational study of Eimeria species in housed cattle on Dutch dairy farms. Vet Parasitol 1995; 56(1-3): 7-16. PMid:7732653. http://dx.doi.org/10.1016/0304-4017(94)00671-X.
http://dx.doi.org/10.1016/0304-4017(94)0...
, Rehman et al. (2011)Rehman TU, Khan MN, Sajid MS, Abbas RZ, Arshad M, Iqbal Z, et al. Epidemiology of Eimeria and associated risk factors in cattle of district Toba Tek Singh, Pakistan. Parasitol Res 2011; 108(5): 1171-1177. PMid:21110042. http://dx.doi.org/10.1007/s00436-010-2159-5.
http://dx.doi.org/10.1007/s00436-010-215...
, Bangoura et al. (2011)Bangoura B, Mundt HC, Schmäschke R, Westphal B, Daugschies A. Prevalence of Eimeria bovis and Eimeria zuernii in German Cattle herds and factors influencing oocyst excretion. Parasitol Res 2011;109(Suppl 1): 129-138. PMid:21739382. http://dx.doi.org/10.1007/s00436-011-2409-1.
http://dx.doi.org/10.1007/s00436-011-240...
, and Stewart et al. (2008)Stewart ID, Smith RP, Ellis-Iversen J. Eimeria species in cattle on farms in England and Wales. Vet Rec 2008; 162(15): 482-483. PMid:18408197. http://dx.doi.org/10.1136/vr.162.15.482.
http://dx.doi.org/10.1136/vr.162.15.482...
.

The high frequency of positive samples found in the animals studied here was probably due to the focus on young calves, which is the age group of cattle that is most susceptible to coccidiosis. In dairy herds in Holland, 46% of young calves and 43% of older calves presented infection by Eimeria spp., whereas only 16% of cows in the same herds were infected (CORNELISSEN et al. 1995Cornelissen AWCA, Verstegen R, Van Den Brand H, Perie NM, Eysker M, Lam TJGM, et al. An observational study of Eimeria species in housed cattle on Dutch dairy farms. Vet Parasitol 1995; 56(1-3): 7-16. PMid:7732653. http://dx.doi.org/10.1016/0304-4017(94)00671-X.
http://dx.doi.org/10.1016/0304-4017(94)0...
). This suggests that younger animals have higher susceptibility to coccidia, given that clinical cases are almost exclusively seen among animals in this age range (STOCKDALE, 1981Stockdale PHG. Effects of monensin on coccidiosis in ruminants. Vet Med Small Anim Clin 1981; 76(11): 1575-1578. PMid:6916536.; CHIBUNDA et al., 1997Chibunda RT, Muhairwa AP, Kambarage DM, Mtambo MMA, Kusiluka LJM, Kazwala RR. Eimeriosis in dairy cattle farms in Morogoro municipality of Tanzania. Prev Vet Med 1997; 31(3-4): 191-197. PMid:9234443. http://dx.doi.org/10.1016/S0167-5877(96)01131-2.
http://dx.doi.org/10.1016/S0167-5877(96)...
; JONSSON et al., 2011Jonsson NN, Piper EK, Gray CP, Deniz A, Constantinoiu CC. Efficacy of toltrazuril 5% suspension against Eimeria bovis and Eimeria zuernii in Calves and Observations on the Associated Immunopathology. Parasitol Res 2011;109(Suppl S1): S113-S128. PMid:21739381. http://dx.doi.org/10.1007/s00436-011-2408-2.
http://dx.doi.org/10.1007/s00436-011-240...
; BANGOURA et al., 2011Bangoura B, Mundt HC, Schmäschke R, Westphal B, Daugschies A. Prevalence of Eimeria bovis and Eimeria zuernii in German Cattle herds and factors influencing oocyst excretion. Parasitol Res 2011;109(Suppl 1): 129-138. PMid:21739382. http://dx.doi.org/10.1007/s00436-011-2409-1.
http://dx.doi.org/10.1007/s00436-011-240...
).

Eimeria spp. that are considered to be the most pathogenic to cattle are E. bovis and E. zuernii (TOMCZUK et al., 2015Tomczuk K, Grzybek M, Szczepaniak K, Studzińska M, Demkowska-Kutrzepa M, Roczeń-Karczmarz M, et al. Analysis of intrinsic and extrinsic factors influencing the dynamics of bovine Eimeria spp. from central–eastern Poland. Vet Parasitol 2015; 214(1-2): 22-28. PMid:26455571. http://dx.doi.org/10.1016/j.vetpar.2015.09.027.
http://dx.doi.org/10.1016/j.vetpar.2015....
), which were two of the three most frequent species found in the present study, thus this could suggest that the farms studied here were at high risk of cases of clinical coccidiosis. Both of these species have previously been reported in other states of Brazil, such as São Paulo, Bahia and Minas Gerais (REBOUÇAS et al., 1994Rebouças MM, Grasso LMPS, Spósito Filha E, Amaral V, Santos SM, Silva DM. Prevalência e distribuição de protozoários do gênero Eimeria (Apicomplexa: Eimeriidae) em bovinos nos municípios de Altinópolis, Taquaritinga, São Carlos e Guaíra – Estado de São Paulo, Brasil. Rev Bras Parasitol Vet 1994; 3(2): 125-130.; ALMEIDA et al., 2011Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
; BRUHN et al., 2011Bruhn FRP, Lopes MA, Demeu FA, Perazza CA, Pedrosa MF, Guimarães AM. Frequency of species of Eimeria in females of the Holstein-Friesian breed at the post-weaning stage during autumn and winter. Rev Bras Parasitol Vet 2011; 20(4): 303-307. PMid:22166384. http://dx.doi.org/10.1590/S1984-29612011000400008.
http://dx.doi.org/10.1590/S1984-29612011...
, 2012Bruhn FRP, Silva FA Jr, Carvalho AHO, Orlando DR, Rocha CMBM, Guimarães AM. Occurrences of Eimeria spp. and gastrointestinal nematodes in dairy calves in southern Minas Gerais, Brazil. Rev Bras Parasitol Vet 2012; 21(2): 171-175. PMid:22832761. http://dx.doi.org/10.1590/S1984-29612012000200019.
http://dx.doi.org/10.1590/S1984-29612012...
). The prevalence of E. zuernii ranged from 6.83% to 22.6% in those studies, i.e. very close to the frequency of 22.00% that was found in the present study. The spatial distribution of E. bovis in Bahia, where 90% of the farms were contaminated (ALMEIDA et al., 2011Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
), was similar to the distribution of E. bovis found in the present study (86.36%).

E. alabamensis has been reported as the causative agent of coccidiosis among grazing calves (SVENSSON et al., 1993Svensson C, Hooshmand-Rad P, Pehrson B, Törnquist M, Uggla A. Excretion of Eimeria oocysts in calves during their first three weeks after turn-out to pasture. Acta Vet Scand 1993; 34(2): 175-182. PMid:8266895., 1994Svensson C, Uggla A, Pehrson B. Eimeria alabamensis infection as a cause of diarrhoea in calves at pasture. Vet Parasitol 1994; 53(1-2): 33-43. PMid:8091616. http://dx.doi.org/10.1016/0304-4017(94)90014-0.
http://dx.doi.org/10.1016/0304-4017(94)9...
; MARSHALL et al., 1998Marshall RN, Catchpole J, Green JA, Webster KA. Bovine coccidiosis in calves following turnout. Vet Rec 1998; 143(13): 366-367. PMid:9800306. http://dx.doi.org/10.1136/vr.143.13.366.
http://dx.doi.org/10.1136/vr.143.13.366...
; SVENSSON, 2000Svensson C. Excretion of Eimeria alabamensis oocysts in grazing calves and young stock. J Vet Med B Infect Dis Vet Public Health 2000; 47(2): 105-110. PMid:10763379. http://dx.doi.org/10.1046/j.1439-0450.2000.00324.x.
http://dx.doi.org/10.1046/j.1439-0450.20...
). All over Brazil, including the northern region of the state of Paraná, livestock are fed on pastures more often than in stalls. This may explain why the occurrence of this parasite species among the individuals analyzed was the second highest among all results so far (26.75%), and may also explain the broad distribution across the farms (90.91%). The high prevalence of E. alabamensis amongst the animals tested matched the results previously found in Austria, where 45.16% of the animals presented this species (KOUTNY et al., 2012Koutny H, Joachim A, Tichy A, Baumgartner W. Bovine Eimeria species in Austria. Parasitol Res 2012; 110(5): 1893-1901. PMid:22167365. http://dx.doi.org/10.1007/s00436-011-2715-7.
http://dx.doi.org/10.1007/s00436-011-271...
). However, the infection levels found in the present study were much higher than those found elsewhere in Brazil, where the proportion of positive samples ranged from 0.4% to 4.3% among the animals tested and up to 25% of the farms were contaminated (REBOUÇAS et al., 1994Rebouças MM, Grasso LMPS, Spósito Filha E, Amaral V, Santos SM, Silva DM. Prevalência e distribuição de protozoários do gênero Eimeria (Apicomplexa: Eimeriidae) em bovinos nos municípios de Altinópolis, Taquaritinga, São Carlos e Guaíra – Estado de São Paulo, Brasil. Rev Bras Parasitol Vet 1994; 3(2): 125-130.; ALMEIDA et al., 2011Almeida VA, Magalhães VCS, Muniz ES Na, Munhoz AD. Frequency of species of the Genus Eimeria in naturally infected cattle in Southern Bahia, Northeast Brazil. Rev Bras Parasitol Vet 2011; 20(1): 78-81. PMid:21439239. http://dx.doi.org/10.1590/S1984-29612011000100017.
http://dx.doi.org/10.1590/S1984-29612011...
; BRUHN et al., 2011Bruhn FRP, Lopes MA, Demeu FA, Perazza CA, Pedrosa MF, Guimarães AM. Frequency of species of Eimeria in females of the Holstein-Friesian breed at the post-weaning stage during autumn and winter. Rev Bras Parasitol Vet 2011; 20(4): 303-307. PMid:22166384. http://dx.doi.org/10.1590/S1984-29612011000400008.
http://dx.doi.org/10.1590/S1984-29612011...
, 2012Bruhn FRP, Silva FA Jr, Carvalho AHO, Orlando DR, Rocha CMBM, Guimarães AM. Occurrences of Eimeria spp. and gastrointestinal nematodes in dairy calves in southern Minas Gerais, Brazil. Rev Bras Parasitol Vet 2012; 21(2): 171-175. PMid:22832761. http://dx.doi.org/10.1590/S1984-29612012000200019.
http://dx.doi.org/10.1590/S1984-29612012...
; KOUTNY et al., 2012Koutny H, Joachim A, Tichy A, Baumgartner W. Bovine Eimeria species in Austria. Parasitol Res 2012; 110(5): 1893-1901. PMid:22167365. http://dx.doi.org/10.1007/s00436-011-2715-7.
http://dx.doi.org/10.1007/s00436-011-271...
; ENEMARK et al., 2013Enemark HL, Dahl J, Enemark JMD. Eimeriosis in Danish dairy calves – correlation between species, oocyst excretion and diarrhoea. Parasitol Res 2013;112(Suppl S1): 169-176. PMid:23765344. http://dx.doi.org/10.1007/s00436-013-3441-0.
http://dx.doi.org/10.1007/s00436-013-344...
).

A similar study carried out two decades ago in the same region of the present work found that 16.69% of the animals were infected by Eimeria spp. (GUIMARÃES et al. 1995Guimarães JS Jr, Amaral CHS, Carvalho MCM, Pereira ABL. Eimeria spp. (Apicomplexa: Eimeriidae) em bezerros da raça holandesa no norte do Paraná e sudoeste de São Paulo, Brasil. Rev Bras Parasitol Vet 1995; 4(2): 71.), what it is much lower than the occurrence of 51.25% found in the present study, however, Hillesheim & Freitas (2016)Hillesheim LO, Freitas FLC. Ocorrência de eimeriose em bezerros criados em propriedades de agricultura familiar – nota científica. Ciênc Anim Bras 2016; 17(3): 472-481. http://dx.doi.org/10.1590/1089-6891v17i333327.
http://dx.doi.org/10.1590/1089-6891v17i3...
whose worked at southwestern of Paraná, observed 48.2% of samples positives for Eimeria spp., this was very similar with prevalence of the present study. Eimeria alabamensis was found in 26.75% of the samples of the present study, and 9.1% in the work of Hillesheim & Freitas (2016)Hillesheim LO, Freitas FLC. Ocorrência de eimeriose em bezerros criados em propriedades de agricultura familiar – nota científica. Ciênc Anim Bras 2016; 17(3): 472-481. http://dx.doi.org/10.1590/1089-6891v17i333327.
http://dx.doi.org/10.1590/1089-6891v17i3...
, but was not described by Guimarães et al. (1995)Guimarães JS Jr, Amaral CHS, Carvalho MCM, Pereira ABL. Eimeria spp. (Apicomplexa: Eimeriidae) em bezerros da raça holandesa no norte do Paraná e sudoeste de São Paulo, Brasil. Rev Bras Parasitol Vet 1995; 4(2): 71.. These differences between our study and Guimarães et al. (1995)Guimarães JS Jr, Amaral CHS, Carvalho MCM, Pereira ABL. Eimeria spp. (Apicomplexa: Eimeriidae) em bezerros da raça holandesa no norte do Paraná e sudoeste de São Paulo, Brasil. Rev Bras Parasitol Vet 1995; 4(2): 71. work could be associate with the type of samples used, here feces samples were collected among animals without clinical signals, and the other one, most part of the animals (85.5%) had diarrhea.

The broad distribution of Eimeria spp., their increasing prevalence and detection for the first time in our region the pathogenic species E. alabamensis emphasize the importance of bovine coccidiosis in the northern region of the state of Paraná, Brazil. The epidemiology of coccidiosis, occurrences of clinical cases and evaluations on their economic impact on the respective farms need to be assessed in greater detail. Such studies may provide support for development of a control plan for bovine coccidiosis, which could be extrapolated to other Brazilian regions and states.

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Publication Dates

  • Publication in this collection
    19 Feb 2018
  • Date of issue
    Jan-Mar 2018

History

  • Received
    14 Sept 2017
  • Accepted
    21 Nov 2017
Colégio Brasileiro de Parasitologia Veterinária FCAV/UNESP - Departamento de Patologia Veterinária, Via de acesso Prof. Paulo Donato Castellane s/n, Zona Rural, , 14884-900 Jaboticabal - SP, Brasil, Fone: (16) 3209-7100 RAMAL 7934 - Jaboticabal - SP - Brazil
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