Status of oxidative stress,trace elements,sialic acid and cholinesterase activity in cattle naturally infected with Babesia bigemina

Babesia bigemina infection (also known as Texas fever) is reported as the most prevalent and main causative agent of bovine babesiosis, worldwide. The current study was undertaken to assess indicators of oxidative stress including activities of antioxidant enzymes and total antioxidant capacity (TAC), oxidation status of biomolecules and serum levels of trace elements as well as indicators of inflammation including sialic acid (SA) contents and cholinesterase activity in cattle naturally infected with B. bigemina. An infected group comprised of 20 crossbred Holstein cattle (3–4 years old) were diagnosed to be positive by both microscopy and nested PCR assay. The infected animals were subdivided into two groups according to their parasitemia rates (<20 % and>20 %). Furthermore, 10 healthy cattle were included as the control. The infection caused severe anemia in a parasitemia-burden dependent fashion. The activities of catalase and glucose-6-phosphate dehydrogenase as well as the levels of TAC, zinc, selenium, copper and manganese were significantly decreased as the parasitemia increased, accordingly. However, the activity of superoxide dismutase as well as the levels of malondialdehyde, protein carbonylation, DNA damage and iron, were significantly elevated in a parasitemeia-burden dependent manner. Additionally, glutathione peroxidase activity was significantly elevated with the lower rate of parasitemia, but the higher rate had no significant effect as compared to control. Moreover, total, protein and lipid binding SA contents were significantly increased but the activities of acetylcholinesterase and butyrylcholinesterase were significantly reduced, parasitemia dependently. Conclusively, the infection was remarkably associated with the induction of anemia, oxidative stress and inflammation.     

Evaluation of some acute phase proteins in cattle naturally infected with Babesia bigemina

Bovine babesiosis due to Babesia bigemina infection induces systemic inflammation, evidenced by increased sialic acid (SA) levels and declined cholinesterase activity. The current study was undertaken to assess further indicators of the systemic inflammation in the naturally infected cattle. To this end, serum levels of some selected acute phase-proteins (APPs) including serum amyloid A (SAA), haptoglobin (Hp), ceruloplasmin (Cp), and fibrinogen were measured. Additionally, sensitivity and specificity of the APPs were calculated by receiver operating characteristic curve. The correlation among APPs, SA and cholinesterase activity were also assessed. Our previous blood specimens were used to measure APPs. Briefly, the diseased animals were divided into two groups according to the parasitemia: 12 mildly (20 % <) and 8 severely (20 %>) infected animals. Moreover, 10 healthy animals as the control were included. The levels of all APPs were measured to be significantly elevated in a parasitemia burden-dependent fashion as compared to the control. Furthermore, all the APPs showed 100 % specificity, but only SAA and Cp had 100 % sensitivity. A strong and positive correlation was calculated between the APPs and SA; however, cholinesterase activity was inversely correlated with AAPs and SA. In conclusion, inflammatory reactions play a pivotal role in the pathogenesis of bovine babesiosis and APPs can be considered as the potential indicators of inflammation.     

Incidence of babesiosis and anaplasmosis infections in cattle sampled monthly in the Mexican states of Nuevo Leon and San Luis Potosi

Serum samples from 200 cattle of various ages and breeds from five ranches in the Mexican states of Neuvo Leon and San Luis Potosi were collected monthly (with occasional omissions) between February 1983 and November 1983. These samples were tested for the presence of antibody activity to Babesia bovis and B. bigemina using the indirect fluorescent antibody test and to Anaplasma marginale using the card test. There were seroconversions to Babesia spp. on two of the five ranches. On one ranch, five of 37 animals originally negative for B. bigemina became positive in late summer and fall. On the other ranch, 32 of 36 animals seroconverted to B. bigemina throughout the study period with a moderate peak in mid-summer. Only four of 35 animals became seropositive to B. bovis on this same ranch. Seroconversions to A. marginale were detected on four of the five ranches with the majority occurring on the same ranches with Babesia infections.     

Erythrocytic oxidative damage in crossbred cattle naturally infected with Babesia bigemina

This study aimed to determine the erythrocytic lipid peroxidation and haemoglobin oxidation as contributory factors causing anaemia in cattle (Friesian × Egyptian native breed) infected with Babesia bigemina. Blood was collected from 32 cows infected with B. bigemina along with 18 healthy cows as controls for determination of erythrocytic malondialdehyde (MDA), blood methaemoglobin (MetHb), plasma free haemoglobin (PHb), corpuscular osmotic fragility (COF), red blood cell count (RBC), total haemoglobin (Hb) and packed cell volume (PCV). Percentage of parasitaemia varied from 14% to 36%. MDA, MetHb, COF and PHb were significantly increased (P < 0.001) in infected cows versus controls. Parasitaemia was positively correlated (P < 0.001) with MDA, MetHb, COF and PHb. MDA was positively correlated (P < 0.001) with COF and PHb and negatively correlated (P < 0.001) with RBC, Hb and PCV. MetHb was negatively correlated (P < 0.001) with RBC, Hb and PCV and positively correlated (P < 0.001) with COF. In conclusion, B. bigemina infection in cattle is associated with a parasitic burden-dependent corpuscular oxidative damage as indicated by membrane lipid peroxidation and methaemoglobin formation, which are contributed to COF and intravascular haemolysis.     

Babesia bigemina infection in yak (Poephagus grunniens L.): Molecular detection and characterization

Yaks contribute significantly in the Himalayan high land economy. Specific information on prevalence of babesiosis in yaks is lacking. A fast and reliable PCR assay targeting Babesia bigemina small subunit ribosomal RNA sequence (SS rRNA) was laboratory standardized for molecular detection of B. bigemina in yaks. Restriction digestion of the PCR amplified 675 bp target sequence with Vsp I confirmed the prevalent species of Babesia as B. bigemina. Nucleotide sequencing and phylogenetic analysis of PCR amplified 675 bp SS rRNA sequence revealed a close genetic relationship with other bovine isolates of B. bigemina. A PCR based survey involving 94 blood samples of yak from the National Research Centre on Yak, Dirang, Arunachal Pradesh detected infection in 5.32% of yak blood samples, which was significantly higher in comparison to microscope based detection of infection in 2.13% blood smears. This is the first report on sensitive PCR based detection of B. bigemina infection in yaks and PCR-RFLP and nucleotide sequence analysis based molecular characterization of the B. bigemina isolated from yaks.     

Molecular detection of Theileria and Babesia infections in cattle

This study was carried out to determine the presence and distribution of tick-borne haemoprotozoan parasites (Theileria and Babesia) in apparently healthy cattle in the East Black Sea Region of Turkey. A total of 389 blood samples were collected from the animals of various ages in six provinces in the region. Prevalence of infection was determined by reverse line blot (RLB) assay. The hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified with a set of primers for members of the genera Theileria and Babesia. Amplified PCR products were hybridized onto a membrane to which generic- and species-specific oligonucleotide probes were covalently linked. RLB hybridization identified infection in 16.19% of the samples. Blood smears were also examined microscopically for Theileria and/or Babesia spp. and 5.14% were positive. All samples shown to be positive by microscopy also tested positive with RLB assay. Two Theileria (T. annulata and T. buffeli/orientalis) and three Babesia (B. bigemina, B. major and Babesia sp.) species or genotypes were identified in the region. Babesia sp. genotype shared 99% similarity with the previously reported sequences of Babesia sp. Kashi 1, Babesia sp. Kashi 2 and Babesia sp. Kayseri 1. The most frequently found species was T. buffeli/orientalis, present in 11.56% of the samples. T. annulata was identified in five samples (1.28%). Babesia infections were less frequently detected: B. bigemina was found in three samples (0.77%), B. major in two samples (0.51%) and Babesia sp. in five samples (1.28%). A single animal infected with T. buffeli/orientalis was also infected with B. bigemina.     

Effect of total alkaloid ofPeganum harmala L. in the treatment of experimental haemosporidian infections in cattle

Cattle experimentally infected withBabesia bigemina orTheileria sergenti or mixed infestations of the two parasites were treated with Total Alkaloid ofPeganum harmala L. The results showed that treatment was effective againstB. bigemina infection, had a marked effect on the course of infection withT. sergenti and some effect on the course of the mixed infection.

     

The use of tick transmission by Boophilus microplus to isolate pure strains of Babesia bovis,Babesia bigemina and Anaplasma marginale from cattle with mixed infections

Pure strains of Babesia bovi, Babesia bigemina and Anaplasma marginale were isolated from cattle infected with all 3 species as well as a Theileria sp. and Eperythrozoon teganodes, using only transmission by the tick, Boophilus microplus. Unengorged adult ticks transferred to susceptible cattle transmitted A. marginale, but not Babesia. Engorged adults gave rise to progeny that transmitted Babesia, B. bovis by larvae and B. bigemina by male ticks. The Theileria and E. teganodes were not transmitted by the ticks and thus did not appear in calves used for isolating the pure strains of Babesia and A. marginale.     

A comparative study of ELISA and other methods for the detection of Brucella antibodies in bovine sera

Enzyme-linked immunosorbent assay (ELISA), using β-galactosidase and a fluorigenic substrate, was used for the detection of antibodies to Brucella abortus in bovine sera.Among 677 animals from 9 brucellosis-free herds, none reacted in the ELISA. Among 785 animals from 23 brucellosis-infected herds, 336 were positive in ELISA, 229 in the slow agglutination test (SAT), 185 in the complement fixation test (CFT), and 165 in the Rose-Bengal test (RBT).Experimental infections were conducted with two B. abortus strains. At slaughter on day 101, after intraconjunctival infection of heifers with B. abortus strain 19 organisms, 3 animals were positive in the SAT, 3 in the CFT, 4 in the RBT and 11 in the ELISA, and Brucella organisms could be cultivated from 10 animals; among these, 2 scored positive in the SAT, 3 in the CFT, 3 in the RBT and 8 in the ELISA test. Seventeen heifers were infected with organisms of B. abortus strain 2308. On day 101, 11 heifers were found to be carriers, all of which yielded positive results in the CFT, RBT and ELISA tests, but not in the SAT.     

Interleukin-2 and interleukin-10 gene expression in calves experimentally infected with Fasciola gigantica

The gene expression of interleukin-2 and interleukin-10 in calves with a primary infection of Fasciola gigantica was studied. Five calves were infected orally with a dose of 1000 viable metacercariae of F. gigantica and five calves served as uninfected control animals. Expression of two cytokine genes i.e. IL-2 and IL-10 (Th1 and Th2) was measured at 10, 30 and 75 days post-infection (PI) by real-time polymerase chain reaction with the double stranded DNA-binding dye SYBR Green. Interleukin-2 was not detected in the peripheral blood mononuclear cells (PBMCs) of infected or control animals at 10, 30 and 75 days PI, however, IL-10 was present in detectable levels in PBMCs of infected animals at 10, 30 and 75 days PI, with no expression of this cytokine in the control animals. With an increased expression of IL-10 and no expression of IL-2 cytokine gene, the present study suggests that F. gigantica infection in calves evoked Th2 immune response.     

Effect of age on the immune response of cattle experimentally infected with Babesia bigemina

Two different age groups of Holstein Friesian cattle were experimentally infected with Babesiabigemina. Calves of group A (6 months old) did not show noticeable symptoms of babesiosis and had relatively low (0.6%) numbers of parasites in their red blood cells (RBCs). Group B calves (1 year old) had typical signs of the disease; parasites were found in 6.6% of their RBCs. Blood from both groups inoculated into splenectomized calves at 3, 6, 12 and 18 months following initial inoculation demonstrated the presence of B. bigemina, while after 22 months no parasites could be demonstrated.The indirect fluorescent antibody (IFA) test detected babesial antibodies at 4–5 days post inoculation (PI) and reached a maximum titre of 1 : 640 at 2 weeks PI. Following challenge at 2–3 months after initial inoculation, the antibody titre rose sharply to 1 : 2560, then decreased gradually but was still detectable 22 months PI. No correlation was found between antibody titre and the presence of the parasite hin the peripheral blood.     

Experimental infection of dogs with various Bartonella species or subspecies isolated from their natural reservoir

Dogs can be infected by a wide variety of Bartonella species. However, limited data is available on experimental infection of dogs with Bartonella strains isolated from domestic animals or wildlife. We report the inoculation of six dogs with Bartonella henselae (feline strain 94022, 16S rRNA type II) in three sets of two dogs, each receiving a different inoculum dose), four dogs inoculated with B. vinsonii subsp. berkhoffii type I (ATCC strain, one mongrel dog) or type II (coyote strain, two beagles and one mongrel) and B. rochalimae (coyote strain, two beagles). None of the dogs inoculated with B. henselae became bacteremic, as detected by classical blood culture. However, several dogs developed severe necrotic lesions at the inoculation site and all six dogs seroconverted within one to two weeks. All dogs inoculated with the B. v. berkhoffii and B. rochalimae strains became bacteremic at levels comparable to previous experimental infections with either a dog isolate or a human isolate. Our data support that dogs are likely accidental hosts for B. henselae, just like humans, and are efficient reservoirs for both B. v. berkhoffii and B. rochalimae.     

Induction of local and systemic immune reactions following infection of turkeys with avian Metapneumovirus (aMPV) subtypes A and B

Most of the studies regarding the immunopathogenesis of avian Metapneumovirus (aMPV) have been done with subtype C of aMPV. Not much is known about the immunopathogenesis of aMPV subtypes A and B in turkeys. Specifically, local immune reactions have not been investigated yet. We conducted two experiments in commercial turkeys. We investigated local and systemic humoral and cell mediated immune reactions following infection with an attenuated vaccine strain of aMPV subtype B (Experiment I) and virulent strains of aMPV subtypes A and B (Experiment II). Turkeys infected with virulent aMPV strains developed mild respiratory signs while birds inoculated with the attenuated aMPV did not show any clinical signs. Virus neutralizing antibodies were detected locally in tracheal washes and systemically in serum as soon as 5-7 days post aMPV infection (PI) independent of the strain used. Virus neutralizing antibody titres peaked at 7 days PI and then antibody levels declined. The peak of serum ELISA antibody production varied between infected groups and ranged from 14 and 28 days PI. All aMPV strains induced an increase in the percentage of CD4+ T cell populations in spleen and Harderian gland at days 7 or 14 PI. Furthermore, as shown in Experiment I, infection with the attenuated aMPV-B strain stimulated spleen leukocytes to release significantly higher levels of interferons (IFNs), interleukin-6 and nitric oxide in ex vivo culture in comparison to virus-free controls up to 7 days PI (P<0.05). As detected by quantitative real time RT-PCR in Experiment II, infection with virulent aMPV induced an increased IFNgamma expression in the Harderian gland in comparison to virus-free controls. IFNgamma expression in the spleen varied between aMPV strains and days PI. Overall, our study demonstrates that aMPV subtypes A and B infection induced humoral and cell mediated immune reactions comparable to subtype C infections. We observed only temporary stimulation of serum virus neutralizing antibodies and of most of the local immune reactions independent of the aMPV strain used. The temporary character of immune reactions may explain the short duration of protection against challenge following aMPV vaccination in the field.     

Influence of Trypanosoma evansi in blood, plasma, and brain cholinesterase of experimentally infected cats

Changes in blood, plasma and brain cholinesterase activities in Trypanosoma evansi-infected cats were investigated. Seven animals were infected with 10⁸ trypomastigote forms each and six were used as control. Animals were monitored for 56 days by examining daily blood smears. Blood samples were collected at days 28 and 56 post-inoculation to determine the activity of acetylcholinesterase (AChE) in blood and the activity of butyrylcholinesterase (BChE) in plasma. AChE was also evaluated in total brain. The activity of AChE in blood and brain, and the activity of BChE in plasma significantly reduced in the infected cats. Therefore, the infection by T. evansi influenced cholinesterases of felines indicating changes in the responses of the cholinergic system.     

Polymorphism,coupling interval and prematurity index in dogs with degenerative mitral valve disease and ventricular arrhythmias

Ventricular arrhythmias (VA) are a recognized concern in dogs with degenerative mitral valve disease (DMVD). The coupling interval (CI) and the prematurity index (PI) have been shown to accurately differentiate between benign and malignant VA in people, where ventricular arrhythmias are known to be associated with an increased risk of development of signs of heart failure or sudden death. In this study, we characterized ventricular arrhythmias in dogs with symptomatic and asymptomatic DMVD. Seventy dogs with naturally-occurring DMVD and ventricular arrhythmias were retrospectively studied. A cross-sectional investigation including dogs with either symptomatic (stages C/D; n?=?41) or asymptomatic (stages B1/B2; n?=?29) DMVD was performed. Electrocardiographic tracings were reviewed to calculate both the CI and PI. In eight dogs these indices were compared with those obtained from both a Holter recording and a standard ECG tracing and no statistical differences were found (CI, p?=?0.97; PI, p?=?0.17). Even though CI and PI were determined in all animals enrolled in the study, VPC characteristics were only compared between symptomatic and asymptomatic dogs when a 24-h Holter recording was available (n?=?49). The PI was different (p?=?0.01) between symptomatic (0.65?±?0.17) and asymptomatic (0.56?±?0.18) dogs, but CI was considered similar (p?=?0.91). Also, the symptomatic dogs had more polymorphic VPC (p?=?0.002) and supraventricular arrhythmias (p?=?0.0002) than the asymptomatic animals. Polymorphism, and repeating patterns of ventricular premature complexes, were characteristics frequently present in overtly symptomatic animals affected by mitral endocardiosis.     

A strain of Babesia divergens, attenuated after long term culture

The Weybridge strain of Babesia divergens became less virulent after 18 months in culture and was believed to be attenuated. Inoculations with the attenuated line using as many as 5 x 10(8) infected erythrocytes failed to raise a normal infection in Mongolian gerbils (Meriones unguiculatus) whereas, with the line that had been passaged from culture through gerbils at bimonthly intervals, inoculations of 10(7) infected erythrocytes gave rise to fatal infections. Gerbils were immunised with the attenuated line using doses ranging from 5 x 10(5) to 5 x 10(7) infected erythrocytes. Parasitaemias in the infected gerbils did not exceed 0.7 per cent after immunisation. All animals were protected when challenged with the virulent line four weeks later. Control animals died four days after challenge infection.     

A seroepidemiologic study of bovine babesiosis in the Mexican states of Nuevo Leon,Tamaulipas and Coahuila

A total of 1885 serum samples were collected in 1982 and 1983 from 40 ranches in the northeastern Mexican states of Nuevo Leon, Tamaulipas and Coahuila. These sera were tested for antibody activity to Babesia bovis and B. bigemina using the indirect fluorescent antibody test. Herd prevalence rates ranged from 0 to 100% for both Babesia spp. Average herd prevalence rates were 50 and 56% for B. bovis and B. bigemina, respectively. Herd prevalence rates for the two Babesia spp. were highly correlated (r = 0.827, 0.638 ? ? ? 0.922, 99% confidence interval). When an analysis of joint positivity to both Babesia spp. in individual animals was performed, the null hypothesis of no association was rejected for 22 of 37 ranches.     

Effect of breed of cattle on innate resistance to infection with <i>Babesia bovis, B bigemina and Anaplasma marginale

Objective To assess the innate resistance of naive Bos taurus, Bos taurus cross Bos indicus and Bos indicus cattle to virulent Babesia bovis, B bigemina and Anaplasma marginale parasites. Design Groups of 10, pure B indicus, fi B indicus cross,/B indicus cross and pure B taurus steers were infected with virulent B bovis, B bigemina and A marginale parasites. Procedure Sequential infections were carried out by intravenous inoculation of infected blood containing 1 times 10⁸ parasites of B bovis, followed by B bigemina and then A marginale. To assess resistance, measurements were made of parasitaemia, rectal temperature, packed cell volume and the number within a group requiring chemotherapy to control infection. There was a recovery period between each infection. Results Infection with B bovis showed that pure B indicus steers were significantly more resistant to B bovis infection than the other groups, with none of this group requiring treatment. There was no significant difference between fi B indicus cross and/B indicus cross with 30% and 20%, respectively, of steers in these groups requiring treatment. The pure B taurus steers were significantly more affected then those in the other three groups with 80% requiring treatment. Infections of B bigemina produced a mild response in comparison to that of B bovis and none of the steers required treatment. However, the pure B taurus group was significantly more affected than the other three groups for all other measurements. After the A marginale infection, B indicus steers were moderately affected with 50% requiring treatment, whereas 70% of the fi B indicus group, 80% of the /B indicus cross group and 100% of the pure B taurus group required treatment. Conclusions All breeds of cattle, ranging from pure B indicus to pure B taurus may be at risk of severe disease if exposed to virulent A marginale. The results confirm that pure B indicus cattle are relatively resistant to B bovis, but there could be a significant risk of severe mortalities if cross-bred herds are exposed to virulent infection.     

A technique to establish a laboratory colony of Boophilus microplus infected with Babesia bigemina

A technique was evolved for the establishment and maintenance of a colony Boophilus microplus free of infection with Anaplasma marginale and Babesia spp., and for their subsequent infection with a pure isolate of Babesia bigemina. Confirmation was obtained that the ticks are infected normally during the last 24 h of attachment on the host. The life cycle of Boophilus microplus was described for a single situation on the Atlantic Coast of Colombia.     

Immunization with Eimeria ninakohlyakimovae-live attenuated oocysts protect goat kids from clinical coccidiosis

Caprine coccidiosis, affecting mainly young goat kids around the weaning period, is worldwide the most important disease in the goat industry. Control of caprine coccidiosis is increasingly hampered by resistances developed against coccidiostatic drugs leading to an enhanced need for anticoccidial vaccines. In the current study we conducted an oral immunization trial with live attenuated sporulated Eimeria ninakohlyakimovae oocysts. Sporulated E. ninakohlyakimovae oocysts were attenuated by X-irradiation technique. The experimental design included a total of 18 goat kids divided into the following groups: (i) animals immunized with attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-irradiated homologous oocysts (group 1); (ii) animals infected with non-attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-attenuated homologous oocysts (group 2); (iii) animals primary-infected with untreated E. ninakohlyakimovae oocysts at 8 weeks of age (control of the challenge infection, group 3); (iv) non-infected control animals (group 4). Goat kids immunized with live attenuated E. ninakohlyakimovae oocysts (group 1) excreted significantly less oocysts in the faeces (95.3% reduction) than kids infected with non-attenuated ones (group 2). Furthermore, immunization with live but attenuated oocysts resulted in ameliorated clinical coccidiosis compared to goat kids infected with untreated oocysts (group 2) and resulted in equally reduced signs of coccidiosis after challenge infection compared to acquired immunity driven by non-attenuated oocysts. Overall, the present study demonstrates for the first time that live attenuated E. ninakohlyakimovae oocysts orally administered showed almost no pathogenicity but enough immunogenicity in terms of immunoprotection. Importantly, vaccinated animals still shed low amounts of oocysts, guaranteeing environmental contamination and consecutive booster infections to sustain ongoing immunity.