Construction of DNA vaccines encoding Eimeria acervulina cSZ-2 with chicken IL-2 and IFN-γ and their efficacy against poultry coccidiosis

The study describes vaccination experiments with highly immunogenic sporozoite E. acervulina cSZ-2 co-administered with chicken IL-2 (chIL-2) and interferon-γ (chIFN-γ) to determine their efficacies against homologue challenge. The entire coding sequence of cSZ2, chIL-2 and chIFN-γ were cloned into eukaryotic expression vector pVAX1, constructing DNA vaccines pVAX1-cSZ2, pVAX1-chIL-2, pVAX1-chIFN-γ, pVAX1-cSZ2-chIL-2 and pVAX1-cSZ2-chIFN-γ. The expression of target genes in vivo was detected by RT-PCR and Western blot. Chicken experiments were carried out by vaccinating chickens two times at dose rate of 100 μg intramuscularly. At 28 days of age, all chickens were inoculated orally with 1 × 10⁵ sporulated oocysts of E. acervulina except the unchallenged control group. Seven days after challenge, all chickens were weighted and slaughtered for duodenum collection. The results indicated that these DNA vaccines were successfully constructed and the antigen genes could be expressed effectively in vivo. The findings also demonstrated best synergistic effect of IL-2 with this protein which suggested that co-administration of cytokines with this antigen was a powerful method to enhance immunity by alleviating intestinal lesions, body weight loss and oocyst count imparting partial protection against homologous challenge.     

Chemical immobilisation of free-ranging Pampas foxes (Pseudalopex gymnocercus): Assessment of ketamine–xylazine and tiletamine–zolazepam combinations

Two protocols to immobilise free-ranging Pampas foxes for ear-tagging or radio-collaring were evaluated. One hundred fifteen foxes were injected with ketamine–xylazine (K–X) and thirteen with tiletamine–zolazepam (T–Z). The use of both T–Z and K–X combinations typically resulted in a smooth induction and recovery. In 86% of the cases K–X protocol was judged effective (mean ± SD, K: 10.7 ± 3.3 mg/kg, X: 1.0 ± 1.0 mg/kg) while T–Z protocol was judged effective in 92% of the cases (T: 3.6 ± 1.05 mg/kg, Z: 3.6 ± 1.05 mg/kg). The primary differences between the two drug combinations were that the time necessary for the complete recovery was longer with T–Z, and thermic problems were found more frequently with K–X. Additionally, our results suggest that thermic stress may be a relatively frequent complication for Pampas foxes. This study provides baseline data on some physiologic variables in Pampas foxes captured with different methods and drugs in field conditions.     

Lungworm infections (Angiostrongylus vasorum, Crenosoma vulpis, Aelurostrongylus abstrusus) in dogs and cats in Germany and Denmark in 2003–2007

Faecal samples of 4151 dogs from Denmark, 958 dogs from Germany and 231 cats from Germany with clinical signs were examined for lungworm larvae using the Baermann funnel technique between 2003 and 2007. In total, 3.6% of Danish and German dogs shed lungworm larvae. In Denmark, patent infections of dogs with Angiostrongylus vasorum were more prevalent (2.2%) than those with Crenosoma vulpis (1.4%). In Denmark, the majority of A. vasorum- (98%) and C. vulpis-infected (80%) dogs originated from Northern Zealand. The frequency of A. vasorum and C. vulpis infections in Danish dogs obviously decreased from 2003 to 2006. In Germany, canine faecal samples were found more frequently positive for C. vulpis than for A. vasorum larvae (2.4% and 1.2%, respectively). Lungworm-infected dogs originated mainly from southern and western Germany. Larvae of Aelurostrongylus abstrusus were detected in 5.6% of cats from Germany. Overall, a distinct seasonal pattern in the detection of infected dogs was apparent for A. vasorum in Denmark and C. vulpis in Germany. The relatively high number of lungworm-infected dogs and cats indicate that these parasitic diseases should be considered in differential diagnosis of cases of treatment-resistant respiratory/cardiopulmonary distress.     

Multiple-class antimicrobial resistance surveillance in swine Escherichia coli F4, Pasteurella multocida and Streptococcus suis isolates from Ontario and the impact of the 2004–2006 Porcine Circovirus type-2 Associated Disease outbreak

The objective of this work was to describe trends in multiple-class antimicrobial resistance present in clinical isolates of Escherichia coli F4, Pasteurella multocida and Streptococcus suis from Ontario swine 1998–2010. Temporal changes in multiple-class resistance varied by the pathogens examined; significant yearly changes were apparent for the E. coli and P. multocida data. Although not present in the E. coli data, significant increases in multiple-class resistance within P. multocida isolates occurred from 2003 to 2005, coinciding with the expected increase in antimicrobials used to treat clinical signs of Porcine Circovirus Associated Disease (PCVAD) before it was confirmed. Prospective temporal scan statistics for multiple-class resistance suggest that significant clusters of increased resistance may have been found in the spring of 2004; months before the identification of the PCVAD outbreak in the fall of 2004.     

Evaluation of Three Enzyme Immunoassays for Diagnosis of Clostridium difficile–Associated Diarrhea in Foals

The aim of the present study was to compare the test performances of three commercial enzyme immunoassays (EIAs) against the toxigenic culture using the cytotoxicity assay as the gold standard. All EIAs showed >78% sensitivity, and the lowest specificity was 92.6%. These results suggest that EIAs could be useful for the diagnosis of Clostridium difficile infection in foals.     

Genetic variation in serological response to Mycobacterium avium subspecies paratuberculosis and its association with performance in Irish Holstein–Friesian dairy cows

Paratuberculosis, also referred to as Johne's disease, is a contagious and chronic disease in ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). Few estimates of the genetic variation in measures of susceptibility to MAP are available in the literature and even less have attempted to elucidate the genetic associations between measures of susceptibility to MAP and performance in dairy cattle. The objectives of this study were to estimate the genetic variation in serological response to MAP in 4789 Holstein–Friesian dairy cows from 44 Irish dairy herds, and to quantify its genetic association with performance traits measured in the first three lactations of genetically related animals. Univariate mixed linear and threshold animal models were used to estimate variance components and genetic correlations were estimated using bivariate animal linear mixed models; MAP serological response was treated as a continuous variable and dichotomous variable. The prevalence of MAP in the sample population was 4.4%. This figure cannot be extrapolated to the national dairy herd as the sample population was biased towards herds with increased likelihood of MAP infection. Estimates of heritability for MAP serological response varied from 0.07 to 0.15 depending on the model of analysis and whether serological response was treated as continuous or binary; standard errors varied from 0.024 to 0.062. Genetic correlations between MAP serological response and lactation milk, fat and protein yield were negative or close to zero although not always more than two standard errors from zero; stronger negative genetic correlations were evident in older parity animals. Serological response to MAP was not genetically correlated with milk fat concentration but was positively genetically correlated with milk protein concentration in first lactation and negatively correlated with calving interval. There was little or no genetic association between serological response to MAP and survival. Results from this study corroborate previous international suggestions that selection for reduced serological response to MAP is possible, although this does not necessarily imply a concurrent selection for either reduced prevalence of clinical disease or increased resistance to MAP infection.     

Spatiotemporal patterns,annual baseline and movement-related incidence of Streptococcus agalactiae infection in Danish dairy herds: 2000–2009

Several decades after the inception of the five-point plan for the control of contagious mastitis pathogens, Streptococcus agalactiae (S. agalactiae) persists as a fundamental threat to the dairy industry in many countries. A better understanding of the relative importance of within- and between-herd sources of new herd infections coupled with the spatiotemporal distribution of the infection, may aid in effective targeting of control efforts. Thus, the objectives of this study were: (1) to describe the spatiotemporal patterns of infection with S. agalactiae in the population of Danish dairy herds from 2000 to 2009 and (2) to estimate the annual herd-level baseline and movement-related incidence risks of S. agalactiae infection over the 10-year period.     

Selection of indigenous lactic acid bacteria to reinforce the intestinal microbiota of newly hatched chicken – relevance of in vitro and ex vivo methods for strains characterization

Based on the natural benefits of the indigenous microbiota, lactic acid bacteria (LAB) from poultry origin were isolated from hens and broilers intestine, and their probiotic potential was further studied. The tolerance to digestion, adhesion, capture of a mannose-binding lectin, absence of virulent factors and antibiotic resistances were studied. Different in vitro and ex vivo assays were performed to select tolerant and adherent strains because standardized protocols have not been defined. Fourteen strains highly tolerant to gastrointestinal digestion were genetically identified. Hydrophobic surfaces were not required for the bacterial adhesion and only nine strains adhered ex vivo to the intestinal mucosa. Three strains captured a lectin of the same specificity of Type-1 fimbriae. Virulence factors were absent but some strains evidenced multiple antibiotic resistances. These results provide bases for a future standardization of methods for the selection of probiotic strains intended to reinforce the microbiota of newly hatched chickens.     

Case–control risk factor study of methicillin-resistant Staphylococcus pseudintermedius (MRSP) infection in dogs and cats in Germany

Methicillin-resistant Staphylococcus pseudintermedius (MRSP) has emerged as a highly drug-resistant small animal veterinary pathogen. Although often isolated from outpatients in veterinary clinics, there is concern that MRSP follows a veterinary-hospital-associated epidemiology. This study's objective was to identify risk factors for MRSP infections in dogs and cats in Germany. Clinical isolates of MRSP cases (n = 150) and methicillin-susceptible S. pseudintermedius (MSSP) controls (n = 133) and their corresponding host signalment and medical data covering the six months prior to staphylococcal isolation were analysed by multivariable logistic regression. The identity of all MRSP isolates was confirmed through demonstration of S. intermedius-group specific nuc and mecA. In the final model, cats (compared to dogs, OR 18.5, 95% CI 1.8–188.0, P = 0.01), animals that had been hospitalised (OR 104.4, 95% CI 21.3–511.6, P < 0.001), or visited veterinary clinics more frequently (>10 visits OR 7.3, 95% CI 1.0–52.6, P = 0.049) and those that had received topical ear medication (OR 5.1, 95% CI 1.8–14.9, P = 0.003) or glucocorticoids (OR 22.5, 95% CI 7.0–72.6, P < 0.001) were at higher risk of MRSP infection, whereas S. pseudintermedius isolates from ears were more likely to belong to the MSSP-group (OR 0.09, 95% CI 0.03–0.34, P < 0.001). These results indicate an association of MRSP infection with veterinary clinic/hospital settings and possibly with chronic skin disease. There was an unexpected lack of association between MRSP and antimicrobial therapy; this requires further investigation but may indicate that MRSP is well adapted to canine skin with little need for selective pressure.     

Effect of dexamethasone and meloxicam on counts of selected T lymphocyte subpopulations and NK cells in cattle – In vivo investigations

The purpose of these investigations has been to assess the in vivo effect of dexamethasone (DEX) and meloxicam (MEL) on percentages and absolute counts of cells within selected T lymphocyte subsets and NK cells in cattle. DEX application caused substantial loss of NK, CD4⁺, CD8⁺ and WC1⁺ T cells, but the drug’s influence on T-cell count was selective, that is it varied according to the presence and intensity of CD25 expression. Reduced counts of T lymphocytes were due to the depletion of CD25⁻CD4⁺, CD25⁻CD8⁺ and CD25⁻WC1⁺ T cells. The loss of CD25⁻CD8⁺ and CD25⁻WC1⁺ T cells was a deep and lasting disorder, whereas the depletion of CD25⁻CD4⁺ T cells was manifested less strongly and regressed promptly. The administration of DEX did not affect absolute counts of CD25^lowCD4⁺ and CD25^lowCD8⁺ T cells, but induced an increase in percentages and absolute counts of CD25^highCD4⁺, CD25^highCD8⁺, CD25^lowWC1⁺ and CD25^highWC1⁺ T cells. In respect of the effect on counts of CD4⁺, CD8⁺ and WC1⁺ T cells, MEL proved to be a safe medication, because it did not alter counts of these lymphocytes. The administration of MEL led to an increase in the absolute count of NK cells, but the effect did not appear quickly and its development required time.     

Combination of cell culture and quantitative PCR (cc–qPCR) to assess disinfectants efficacy on Cryptosporidium oocysts under standardized conditions

Oocysts of Cryptosporidium parvum are resistant to environmental conditions and many disinfectants. A combination of cell culture and quantitative real time PCR (cc–qPCR) is established for evaluation of anticoccidial disinfectants against C. parvum. C. parvum oocysts were treated with disinfectants, washed and oocysts were incubated with HCT-8 cell monolayers in the presence of excystation medium for 3 h. Subsequently, unbound parasites were removed by washing with growing medium and the infected monolayers were further maintained in fresh growing medium for 48 h. Genomic DNA was extracted from each sample and qPCR performed targeting a specific sequence of the 70 kDa heat shock protein gene in order to quantify development. Treatment of oocysts with cresolic disinfectants demonstrated dose dependent reduction of viability of oocysts. More than 98% inactivations were recorded with at least 2% concentration of cresolic disinfectants after 2 h of treatment. Bleach (sodium hypochlorite) at 6% solution induced 92.7% inactivation of C. parvum oocysts after 2 h. Thermally treated oocysts (56 and 70 °C for 20 min) demonstrated complete inactivation, whereas at 38 °C no inactivation was observed. Application of Neopredisan^® 135-1 and Aldecoc^® TGE (4% for 2 h) as recommended according to the current guidelines stipulated by DVG (German Veterinary Society) consistently inactivated more than 99.5% of oocysts. The suggested cc–qPCR method appeared to be suited for standardized testing of inactivation measures, particularly for evaluation of chemical disinfectants and thus cc–qPCR is proposed as an alternative to the established chicken infectivity model for Eimeria tenella for testing anticoccidial disinfectants. A minimum inactivation of 99.5% in cc–qPCR model is claimed as a suitable threshold for certification of chemical products for disinfection of coccidia oocysts.     

Heterosis in Bos taurus × Bos indicus crosses

Data extracted from reports on Bos taurus × Bos indicus crossbreeding were used to estimate the amount of heterosis in these crosses. Traits studied were age at first calving, milk yield, lactation length, and calving interval. The estimates obtained were (percent of midparent means in parentheses):

     

14.

Prostaglandin F2α regulation of mRNA for activating protein 1 transcriptional factors in porcine corpora lutea (CL): lack of induction of JUN and JUND in CL without luteolytic capacity     

F.J. Diaz  W. Luo  M.C. Wiltbank 《Domestic animal endocrinology》2013

     

15.

Occurrence of ɛ-proteobacterial species in rabbits (Oryctolagus cuniculus) reared in intensive and rural farms     

J. Revez  M. Rossi  S. Piva  D. Florio  A. Lucchi  A. Parisi  G. Manfreda  R.G. Zanoni 《Veterinary microbiology》2013

In order to investigate the occurrence of Campylobacter, Helicobacter and Arcobacter species in caecal contents of rabbits reared in intensive and rural farms, a total of 87 samples from animals belonging to 29 farms were analysed by both cultural and PCR analyses.     

16.

Experimental infection of weaned piglets with Campylobacter coli – Excretion and translocation in a pig colonisation trial     

Katharina Bratz  Roland Bücker  Greta Gölz  Silke S. Zakrzewski  Pawel Janczyk  Karsten Nöckler  Thomas Alter 《Veterinary microbiology》2013

Campylobacter (C.) is one of the most common food-borne pathogen causing bacterial enteric infections in humans. Consumption of meat and meat products that have been contaminated with Campylobacter are the major source of infection. Pigs are a natural reservoir of Campylobacter spp. with C. coli as the dominant species. Even though some studies focussed on transmission of C. coli in pig herds and the excretion in faeces, little is known about the colonisation and excretion dynamics of C. coli in a complex gut microbiota present in weaned piglets and the translocation to different tissues.     

17.

Effects of hops (Humulus lupulus L.) β-acid extract on inulin fermentation by equine fecal microflora in vitro     

B.E. Harlow  L.M. Lawrence  M.D. Flythe 《Journal of Equine Veterinary Science》2013

     

18.

Functional genomics and evolution of tick–Anaplasma interactions and vaccine development     

José de la Fuente  Katherine M. Kocan  Edmour F. Blouin  Zorica Zivkovic  Victoria Naranjo  Consuelo Almazán  Eliane Esteves  Frans Jongejan  Sirlei Daffre  Atilio J. Mangold 《Veterinary parasitology》2010,167(2-4):175-186

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several tick-transmitted pathogens that impact veterinary and human health. Tick-borne pathogens cycle between tick vectors and vertebrate hosts and their interaction is mediated by molecular mechanisms at the tick–pathogen interface. These mechanisms have evolved characteristics that involve traits from both the tick vector and the pathogen to insure their mutual survival. Herein, we review the information obtained from functional genomics and genetic studies to characterize the tick–Anaplasma interface and evolution of A. marginale and A. phagocytophilum. Anaplasma and tick genes and proteins involved in tick–pathogen interactions were characterized. The results of these studies demonstrated that common and Anaplasma species-specific molecular mechanism occur by which pathogen and tick cell gene expression mediates or limits Anaplasma developmental cycle and trafficking through ticks. These results have advanced our understanding of the biology of tick–Anaplasma interactions and have opened new avenues for the development of improved methods for the control of tick infestations and the transmission of tick-borne pathogens.     

19.

Induction of anesthesia and recovery in donkeys sedated with xylazine: a comparison of midazolam–alfaxalone and midazolam–ketamine     

Jill K Maney  H Edward Durham  Kathleen P Goucher  Erika L Little 《Veterinary anaesthesia and analgesia》2018,45(4):539-544

Objective

To compare the induction and recovery characteristics and selected cardiopulmonary variables of midazolam–alfaxalone or midazolam–ketamine in donkeys sedated with xylazine.

Study design

Randomized, blinded, crossover experimental trial.

Animals

A group of seven adult male castrated donkeys weighing 164 ± 14 kg.

Methods

Donkeys were randomly administered midazolam (0.05 mg kg^?1) and alfaxalone (1 mg kg^?1) or midazolam (0.05 mg kg^?1) and ketamine (2.2 mg kg^?1) intravenously following sedation with xylazine, with ≥ 7 days between treatments. Donkeys were not endotracheally intubated and breathed room air. Time to lateral recumbency, first movement, sternal recumbency and standing were recorded. Induction and recovery were assigned scores between 1 (very poor) and 5 (excellent). Heart rate (HR), respiratory rate (f_R), invasive arterial blood pressures and arterial blood gases were measured before induction and every 5 minutes following induction until first movement.

Results

Time to lateral recumbency (mean ± standard deviation) was shorter after alfaxalone (29 ± 10 seconds) compared with ketamine (51 ± 9 seconds; p = 0.01). Time to first movement was the same between treatments (27 versus 23 minutes). Time to standing was longer with alfaxalone (58 ± 15 minutes) compared with ketamine (33 ± 8 minutes; p = 0.01). Recovery score [median (range)] was of lower quality with alfaxalone [3 (2–5)] compared with ketamine [5 (3–5); p = 0.03]. There were no differences in HR, f_R or arterial pressures between treatments. No clinically important differences in blood gases were identified between treatments. Five of seven donkeys administered alfaxalone became hypoxemic (PaO₂ <60 mmHg; 8.0 kPa) and all donkeys administered ketamine became hypoxemic (p = 0.13).

Conclusions and clinical relevance

Both midazolam–alfaxalone and midazolam–ketamine produced acceptable anesthetic induction and recovery in donkeys after xylazine sedation. Hypoxemia occurred with both treatments.     

20.

Anti-abortion and Fertility Vaccine Potential of Defined Double Deletion (ΔaroAΔhtrA) Mutant (S30) of Salmonella Abortusequi in Equids     

Mudit Chandra  Bhoj Raj Singh  Nagarajan Babu  Ravi Kant Agarwal  Mahtab Z. Siddiqui 《Journal of Equine Veterinary Science》2014

The present study on defined double deletion (ΔaroAΔhtrA) mutant (S30) of Salmonella enterica serovar Abortusequi evaluated it for safety, immunogenicity, and efficacy as a vaccine candidate in equids. The candidate strain was found safe in equids (foals, male and female horses and donkeys, and pregnant and nonpregnant mares) and induced good humoral and cell-mediated immunity on administration through oral route. The strain was not excreted in feces of vaccinated animals. The vaccine candidate administered orally (1 × 10¹¹ cfu per animal) protected mares even after 180 days of inoculation against abortion on challenge with wild-type S. Abortusequi strain whereas in nonvaccinated control, all mares aborted. The vaccination in infertile mares resulted in regaining of fertility in 67%–80% thoroughbred mares at two different breeding farms. Further, the humoral immunity was transferred to foals from vaccinated mothers through colostrum, but no placental transfer was evident. Thus, the vaccine under study may be recommended for use in equids to control S. Abortusequi infection–associated abortions and also to enhance fertility of temporarily infertile mares in endemic areas.     

Age at first calving	?3.2 to ?4.4 months	(?8 to ?12%)
Milk yield	287 to 400 kg	(18 to 25%)
Lactation length	7 to 15 days	(2 to 5%)
Calving interval	?30 to ?31 days	(?7%)

Occurrence of ɛ-proteobacterial species in rabbits (Oryctolagus cuniculus) reared in intensive and rural farms

In order to investigate the occurrence of Campylobacter, Helicobacter and Arcobacter species in caecal contents of rabbits reared in intensive and rural farms, a total of 87 samples from animals belonging to 29 farms were analysed by both cultural and PCR analyses.     

Experimental infection of weaned piglets with Campylobacter coli – Excretion and translocation in a pig colonisation trial

Campylobacter (C.) is one of the most common food-borne pathogen causing bacterial enteric infections in humans. Consumption of meat and meat products that have been contaminated with Campylobacter are the major source of infection. Pigs are a natural reservoir of Campylobacter spp. with C. coli as the dominant species. Even though some studies focussed on transmission of C. coli in pig herds and the excretion in faeces, little is known about the colonisation and excretion dynamics of C. coli in a complex gut microbiota present in weaned piglets and the translocation to different tissues.     

Functional genomics and evolution of tick–Anaplasma interactions and vaccine development

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several tick-transmitted pathogens that impact veterinary and human health. Tick-borne pathogens cycle between tick vectors and vertebrate hosts and their interaction is mediated by molecular mechanisms at the tick–pathogen interface. These mechanisms have evolved characteristics that involve traits from both the tick vector and the pathogen to insure their mutual survival. Herein, we review the information obtained from functional genomics and genetic studies to characterize the tick–Anaplasma interface and evolution of A. marginale and A. phagocytophilum. Anaplasma and tick genes and proteins involved in tick–pathogen interactions were characterized. The results of these studies demonstrated that common and Anaplasma species-specific molecular mechanism occur by which pathogen and tick cell gene expression mediates or limits Anaplasma developmental cycle and trafficking through ticks. These results have advanced our understanding of the biology of tick–Anaplasma interactions and have opened new avenues for the development of improved methods for the control of tick infestations and the transmission of tick-borne pathogens.     

Induction of anesthesia and recovery in donkeys sedated with xylazine: a comparison of midazolam–alfaxalone and midazolam–ketamine

Objective

To compare the induction and recovery characteristics and selected cardiopulmonary variables of midazolam–alfaxalone or midazolam–ketamine in donkeys sedated with xylazine.

Anti-abortion and Fertility Vaccine Potential of Defined Double Deletion (ΔaroAΔhtrA) Mutant (S30) of Salmonella Abortusequi in Equids

The present study on defined double deletion (ΔaroAΔhtrA) mutant (S30) of Salmonella enterica serovar Abortusequi evaluated it for safety, immunogenicity, and efficacy as a vaccine candidate in equids. The candidate strain was found safe in equids (foals, male and female horses and donkeys, and pregnant and nonpregnant mares) and induced good humoral and cell-mediated immunity on administration through oral route. The strain was not excreted in feces of vaccinated animals. The vaccine candidate administered orally (1 × 10¹¹ cfu per animal) protected mares even after 180 days of inoculation against abortion on challenge with wild-type S. Abortusequi strain whereas in nonvaccinated control, all mares aborted. The vaccination in infertile mares resulted in regaining of fertility in 67%–80% thoroughbred mares at two different breeding farms. Further, the humoral immunity was transferred to foals from vaccinated mothers through colostrum, but no placental transfer was evident. Thus, the vaccine under study may be recommended for use in equids to control S. Abortusequi infection–associated abortions and also to enhance fertility of temporarily infertile mares in endemic areas.