Association of different microbes and pathogenic factors in cases of infectious bovine keratoconjunctivitis in cattle from Eastern Kazakhstan.

Background and Aim: Infectious bovine keratoconjunctivitis (IBK) causes a significant economic loss to cattle industries in many countries, including Kazakhstan. Although Moraxella bovis is recognized as an etiologic agent of IBK, other bacterial and viral agents have been suspected to play a role in the pathogenesis of this disease. This study aimed to evaluate samples collected from the eyes of IBK-affected cattle in Eastern Kazakhstan at different stages of IBK for the presence of Mor. bovis, Moraxella bovoculi, Mycoplasma bovis, Mycoplasma bovoculi, and Bovine Herpes Virus Type 1 (BHV-1) and to characterize Mor. bovoculi pilA gene sequence diversity from Mor. bovoculi positive samples. Materials and Methods: Individual ocular swabs (n = 168) were collected from cattle that had clinical signs of IBK during the summer of 2022 on farms in the Abay region of Kazakhstan. Eye lesion scores (1, 2, and 3) were assigned depending on the degree of ocular damage. Infectious bovine keratoconjunctivitis-associated organisms were detected using a multiplex real-time polymerase chain reaction assay. The Mor. bovoculi pilA gene was sequenced from Mor. bovoculi positive samples. Results: Mycoplasma bovis and BHV-1 were not detected in any of the collected samples. Mycoplasma bovoculi was identified in the majority of samples overall, usually in mixed infection with Moraxella spp. Moraxella bovoculi was detected in 76.2% of animals and predominated in animals with eye lesion scores 2 and 3. Mycoplasma bovoculi was detected only in association with Mor. bovis and/or Mor. bovoculi in animals with eye lesion scores 2 and 3. Moraxella bovis was found in 57.7% of animals and was always identified in association with another organism. Sequencing of the pilA gene in 96 samples from Mor. bovoculi positive samples identified five PilA groups. The majority belonged to PilA group A. However, three new PilA groups were identified and designated PilA groups N, O, and P. Conclusion: The results indicate a high prevalence of Myc. bovoculi and Mor. bovoculi in eyes of cattle with IBK on livestock farms in Eastern Kazakhstan. Additional novel Mor. bovoculi PilA groups were identified.

Randomized controlled field trial to assess the efficacy of an intranasal Moraxella bovis cytotoxin vaccine against naturally occurring infectious bovine keratoconjunctivitis.

Background: Infectious bovine keratoconjunctivitis (IBK; pinkeye) is generally considered to be caused by corneal infections with Moraxella bovis. Previous studies demonstrated that M. bovis cytotoxin-specific mucosal immune responses in the bovine eye can be stimulated by intranasal vaccination with a recombinant M. bovis cytotoxin subunit adjuvanted with polyacrylic acid. Methods: A randomized controlled field trial (two-arm parallel design with blinding) was conducted in beef steers in Northern California to determine if this vaccine could prevent naturally occurring IBK and/or reduce morbidity rates associated with this disease. Beef steers were vaccinated intranasally on days 0 and 21 with either a recombinant M. bovis cytotoxin subunit adjuvanted with polyacrylic acid (Vaccine group) or adjuvant alone (Control group). Eye examinations were performed on all steers every 7 days for 16 weeks to document the occurrence of IBK and to determine sizes of corneal ulcers. Serum and tear samples were collected on days 0, 42, and 112 from a subset of animals to measure changes in systemic and ocular immune responses to M. bovis cytotoxin. Results: The cumulative proportion of steers that developed IBK after 16 weeks did not differ between groups. Variables related to disease severity were numerically lower in steers that received the experimental vaccine. IBK-affected Vaccine group steers had a significantly lower number of observation weeks with severe ulcers versus Control group steers. Cytotoxin-specific tear IgA was significantly higher in Vaccine group compared to Control group steers on day 112. Conclusion: Although the proportion of animals that developed corneal ulcers associated with IBK did not differ between groups, the lowered metrics of disease severity in vaccinated steers suggests that intranasal vaccination with recombinant M. bovis cytotoxin can reduce the severity of IBK in cattle.

Effects of eye patches on corneal ulcer healing and weight gain in stocker steers on pasture: a randomized controlled trial.

Infectious bovine keratoconjunctivitis (IBK) is a painful ocular disease in cattle that is characterized by the presence of a corneal ulcer and production losses. A common industry practice is to cover an affected eye with a piece of cloth to reduce exposure to face flies and ultraviolet light with the goal of alleviating pain, accelerating healing, and reducing spread. To study the efficacy of eye patches in the treatment of IBK, a group of 216 clinically normal Angus crossbred steers were followed between April and August 2019 and evaluated weekly for the development of IBK. Eyes of cattle that developed IBK were enrolled with a blocked randomization scheme based on ulcer severity score to receive either an eye patch (treatment group) or no eye patch (control group). All treatment and control group animals received parenteral antimicrobial and nonsteroidal anti-inflammatory treatments and were housed in a pasture separated from the rest of the cohort for a maximum of 28 d or until clinical cure. Corneal ulcer areas were measured, and body weights were recorded twice weekly for steers in the treatment and control groups. Weights of all steers in the cohort were recorded three times during the trial period. The primary outcome, rate of corneal ulcer healing, was higher (P = 0.001) for lesions in eyes receiving an eye patch as determined by a linear mixed model that controlled for ulcer severity score at enrollment and previous IBK in the opposite eye. Median corneal ulcer healing time was 10 (IQR [Interquartile range] 7-17) d for patched eyes vs. 14 (IQR 7-21) d for unpatched eyes. In a Cox proportional hazards model adjusted for severity score at diagnosis, the hazard ratio for ulcer healing was 1.62 (95% CI: 1.02-2.56, P = 0.042) for eyes that received a patch compared to eyes that did not. Among all 216 steers in the cohort, those that were diagnosed with IBK had a numerically higher average daily gain (ADG) (0.45 [±SE 0.01] kg) vs. those that were not (0.42 [±SE 0.12] kg; P = 0.06). In enrolled steers that received a patch, the secondary outcome ADG was 0.47 (±SE 0.02) kg compared to 0.43 (±SE 0.02) kg in controls (P = 0.22). Weight gain may have been confounded by pasture during the treatment period. Results of this trial support the use of this low-cost intervention; further investigation into possible reasons for observed differences in weight gain may be warranted.

Bovine Immune Responses to Moraxella bovis and Moraxella bovoculi Following Vaccination and Natural or Experimental Infections.

Studies have sought to develop effective vaccines against infectious bovine keratoconjunctivitis (IBK). Most research has focused on parenterally administered vaccines against Moraxella bovis antigens; however, researchers have also included Moraxella bovoculi antigens in vaccines to prevent IBK. Critical knowledge gaps remain as to which Moraxella spp antigens might be completely protective, and whether systemic, mucosal, or both types of immune responses are required for protection against IBK associated with Moraxella spp. Immune responses to commensal Moraxella spp residing in the upper respiratory tract and eye have not been analyzed to determine if these responses control colonization or contribute to IBK.

Future Directions for Research in Infectious Bovine Keratoconjunctivitis.

In this article, the authors summarize the future needs from a research perspective to make the greatest gains. They discuss the areas of research: diagnosis, epidemiology, economic impact, prevention, and treatment. In some areas, simple studies with little cost could be conducted that would quickly add to the evidence base. In other areas, substantial investment is needed if new study approaches, which do not repeat past studies' failures, are to be conducted. To maximize the value of research funding, it is essential to critically evaluate the information gains from prior studies and ensure that studies increase knowledge incrementally.

Relatedness of type IV pilin PilA amongst geographically diverse Moraxella bovoculi isolated from cattle with infectious bovine keratoconjunctivitis.

Introduction. Moraxella bovoculi is frequently isolated from the eyes of cattle with infectious bovine keratoconjunctivitis (IBK; pinkeye). As with M. bovis, which has been causally linked to IBK, M. bovoculi expresses an RTX (repeats in the structural toxin) cytotoxin that is related to M. bovis cytotoxin. Pilin, another pathogenic factor in M. bovis, is required for corneal attachment. Seven antigenically distinct pilin serogroups have been described in M. bovis.Hypothesis/Gap Statement. Multiple different serogroups exist amongst type IV pilin encoded by M. bovis, however, it is not known whether M. bovoculi exhibits a similar degree of diversity in type IV pilin that it encodes.Aim. This study was done to characterize a structural pilin (PilA) encoded by M. bovoculi isolated from cases of IBK to determine if diversity exists amongst PilA sequences.Methodology. Ninety-four isolates of M. bovoculi collected between 2002 and 2017 from 23 counties throughout California and from five counties in four other Western states were evaluated.Results. DNA sequencing and determination of deduced amino acid sequences revealed ten (designated groups A through J) unique PilA sequences that were ~96.1-99.3 % identical. Pilin groups A and C matched previously reported putative PilA sequences from M. bovoculi isolated from IBK-affected cattle in the USA (Virginia, Nebraska, and Kansas) and Asia (Kazakhstan). The ten pilin sequences identified were only ~74-76 % identical to deduced amino acid sequences of putative pilin proteins identified from the previously reported whole-genome sequences of M. bovoculi derived from deep nasopharyngeal swabs of IBK-asymptomatic cattle.Conclusions. Compared to the diversity reported between structural pilin proteins amongst different serogroups of M. bovis, M. bovoculi PilA from geographically diverse isolates derived from IBK-affected cattle are more conserved.

Clinical management and outcomes for goats, sheep, and pigs hospitalized for treatment of burn injuries sustained in wildfires: 28 cases (2006, 2015, and 2018).

OBJECTIVE: To characterize injuries and describe medical management and clinical outcomes of goats, sheep, and pigs treated at a veterinary medical teaching hospital for burn injuries sustained during wildfires. ANIMALS: Goats (n = 9), sheep (12), and pigs (7) that sustained burn injuries from wildfires. PROCEDURES: Medical records were searched to identify goats, sheep, and pigs that had burn injuries associated with California wildfires in 2006, 2015, and 2018. Data regarding signalment, physical examination findings, treatments, clinical outcomes, time to discharge from the hospital, and reasons for death or euthanasia were recorded. RESULTS: The eyes, ears, nose, mouth, hooves, perineum, and ventral aspect of the abdomen were most commonly affected in both goats and sheep. In pigs, the ventral aspect of the abdomen, distal limb extremities, ears, and tail were most commonly affected. The median (range) time to discharge from the hospital for goats and pigs was 11 (3 to 90) and 85.5 (54 to 117) days, respectively. One of 9 goats, 12 of 12 sheep, and 5 of 7 pigs died or were euthanized. Laminitis and devitalization of distal limb extremities were common complications (13/28 animals) and a common reason for considering euthanasia in sheep and pigs. CONCLUSIONS AND CLINICAL RELEVANCE: Burn injuries in small ruminants and pigs required prolonged treatment in some cases. Results suggested prognosis for survival may be more guarded for sheep and pigs with burn injuries than for goats; however, further research is needed to confirm these findings.

Pharmacokinetic Parameters and Estimated Milk Withdrawal Intervals for Domestic Goats (Capra Aegagrus Hircus) After Administration of Single and Multiple Intravenous and Subcutaneous Doses of Flunixin Meglumine.

Introduction: The study objectives were to estimate plasma flunixin (FLU) pharmacokinetic parameters and milk depletion profiles for FLU and its metabolite (5-hydroxy flunixin; 5-OH) after subcutaneous (SC) and intravenous (IV) administration of single and multiple flunixin meglumine (FM) doses to non-lactating (nulliparous and pregnant does) and lactating dairy goats. Analytical methods (ELISA and UPLC-MS/MS) for quantifying plasma FLU concentrations were compared. The final objective was to use regulatory (FDA and EMA) methods to estimate milk withdrawal intervals following extra-label drug use in goats. Methods: FM was administered IV and SC to commercial dairy goats at 1.1 mg/kg for single and multiple doses. Plasma and milk samples were analyzed for FLU and 5-OH via UPLC-MS/MS. Plasma samples were also analyzed for FLU concentrations via ELISA. Using statistical approaches recommended by regulatory agencies, milk withdrawal intervals were estimated following FM extra-label use. Results: Following IV administration of a single FM dose, clearances were 127, 199, and 365 ml/kg/h for non-lactating (NL) pregnant does, NL nulliparous does, and lactating dairy does, respectively. Following multiple SC doses, clearance/F was 199 ml/kg/h for lactating does. After IV administration of a single FM dose, terminal elimination half-lives were 4.08, 2.87, and 3.77 h for NL pregnant does, NL nulliparous does, and lactating dairy does, respectively. After multiple SC doses, the terminal elimination half-life was 3.03 h for lactating dairy does. No significant differences were noted for samples analyzed by UPLC-MS/MS or ELISA. Milk withdrawal intervals ranged from 36 to 60 h depending on the regulatory statistical method and dosage regimen. Conclusions: Subcutaneous administration of FM to goats results in similar plasma pharmacokinetic parameters as IV administration. ELISA analysis is an alternative method to UPLC-MS/MS for quantifying FLU concentrations in caprine plasma samples. Following FM extra-label administration to dairy goats, clinicians could consider 36-60 h milk withdrawal intervals.

Comparative pharmacokinetics of two florfenicol formulations following intramuscular and subcutaneous administration to sheep.

OBJECTIVE To compare the pharmacokinetics of 2 commercial florfenicol formulations following IM and SC administration to sheep. ANIMALS 16 healthy adult mixed-breed sheep. PROCEDURES In a crossover study, sheep were randomly assigned to receive florfenicol formulation A or B at a single dose of 20 mg/kg, IM, or 40 mg/kg, SC. After a 2-week washout period, each sheep was administered the opposite formulation at the same dose and administration route as the initial formulation. Blood samples were collected immediately before and at predetermined times for 24 hours after each florfenicol administration. Plasma florfenicol concentrations were determined by high-performance liquid chromatography. Pharmacokinetic parameters were estimated by noncompartmental methods and compared between the 2 formulations at each dose and route of administration. RESULTS Median maximum plasma concentration, elimination half-life, and area under the concentration-time curve from time 0 to the last quantifiable measurement for florfenicol were 3.76 µg/mL, 13.44 hours, and 24.88 µg•h/mL, respectively, for formulation A and 7.72 µg/mL, 5.98 hours, and 41.53 µg•h/mL, respectively, for formulation B following administration of 20 mg of florfenicol/kg, IM, and 2.63 µg/mL, 12.48 hours, and 31.63 µg•h/mL, respectively, for formulation A and 4.70 µg/mL, 16.60 hours, and 48.32 µg•h/mL, respectively, for formulation B following administration of 40 mg of florfenicol/kg, SC. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that both formulations achieved plasma florfenicol concentrations expected to be therapeutic for respiratory tract disease caused by Mannheimia haemolytica or Pasteurella spp at both doses and administration routes evaluated.

One Health in food safety and security education: Subject matter outline for a curricular framework.

Educating students in the range of subjects encompassing food safety and security as approached from a One Health perspective requires consideration of a variety of different disciplines and the interrelationships among disciplines. The Western Institute for Food Safety and Security developed a subject matter outline to accompany a previously published One Health in food safety and security curricular framework. The subject matter covered in this outline encompasses a variety of topics and disciplines related to food safety and security including effects of food production on the environment. This subject matter outline should help guide curriculum development and education in One Health in food safety and security and provides useful information for educators, researchers, students, and public policy-makers facing the inherent challenges of maintaining and/or developing safe and secure food supplies without destroying Earth's natural resources.

Disorders of performance-age bucking bulls.

OBJECTIVE To describe disorders of performance-age bucking bulls. DESIGN Retrospective case-control study. ANIMALS 78 bucking (cases) and 236 nonbucking (controls) beef bulls. PROCEDURES The medical record database of a referral hospital was reviewed to identify beef bulls > 1 year old that were examined for a medical or musculoskeletal disorder between January 1, 2000, and April 1, 2014. Bucking bulls were designated as cases, and nonbucking bulls were designated as controls. For each bull, the signalment, history, physical examination and diagnostic test results, and clinical diagnosis were recorded. The frequency of each disorder was compared between cases and controls. RESULTS Fifteen of 78 (19%) cases and 132 of 236 (56%) controls had medical disorders; however, the frequency did not differ between the 2 groups for any medical disorder. Musculoskeletal disorders were identified in 55 (70.5%) cases and 109 (46%) controls. Cases were 10.55 times as likely as controls to have horn and sinus disorders. Of the 43 (55%) cases examined because of lameness, the thoracic limb was affected in 19 (44%). Compared with controls, cases were 13.37 and 3.31 times as likely to have a musculoskeletal disorder of the vertebral region and pelvic limb, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated bucking bulls were more likely than nonbucking bulls to develop horn and sinus disorders and musculoskeletal disorders of the vertebral region and pelvic limbs. The limb distribution of lameness for bucking bulls may differ from that for nonbucking bulls.

Antibiotic resistance patterns of bacteria isolated from indwelling Foley catheters following tube cystostomy in goats with obstructive urolithiasis.

Tube cystostomy is a surgical method used for managing obstructive urolithiasis and involves placement of a Foley catheter into the urinary bladder. We identified and evaluated the antibiotic resistance patterns of bacteria isolated from indwelling Foley catheters following tube cystostomy in goats with obstructive urolithiasis. Urine samples collected over a 10-y period from catheter tips at the time of removal were submitted for bacteriologic culture and antibiotic susceptibility testing. Resistance patterns to antibiotics, trends in the resistance patterns over the study period, and the probability of a bacterial isolate being resistant as a function of the identity of the isolate and antibiotic tested were determined. A total of 103 urine samples from 103 male goats with obstructive urolithiasis managed surgically with tube cystostomy were included in the study. Aerococcus (36.9%) and Enterococcus (30.1%) were isolated most frequently. The susceptibility patterns of all bacteria isolated did not change over the study period ( p > 0.05). Proportions of isolates resistant to 1, 2, and ≥3 antibiotics were 36.9%, 18.5%, and 23.3%, respectively. Thus, 41.8% of bacterial isolates were resistant to 2 or more antibiotics tested. The probability of Aerococcus spp., Escherichia coli, and Pseudomonas aeruginosa isolates to be resistant to ampicillin, ceftiofur, erythromycin, penicillin, or tetracycline ranged from 0.59 to 0.76.

Transpalpebral exenteration in cattle: a retrospective study of 115 cases.

OBJECTIVE: To describe the indications for exenteration and complications associated with the procedure. ANIMALS STUDIED: 115 cattle. PROCEDURES: Medical records of cattle presented for unilateral exenteration evaluated at the University of California, Davis Veterinary Medical Teaching Hospital from January 1985 through December 2015 were reviewed. RESULTS: Median (range) age at presentation for all cattle was 6 (0.2-30) years. The most prevalent (80.9%) indication for exenteration was squamous cell carcinoma (SCC). Cattle >5 years had higher odds (OR = 11.2, 95% CI, 2.8-45.8) for undergoing exenteration due to SCC compared to cattle ≤5 years. Herefords had higher odds (OR = 4.6, 95% CI, 1.5-14.6) for undergoing exenteration for SCC compared to other breeds. Holsteins had higher odds (OR = 140.7, 95% CI, 7.5-2644) for undergoing exenteration for retrobulbar lymphoma compared to other breeds. Complications following exenteration were reported in 15 cases (13.0%). The postsurgical complications were orbital abscesses (6/15), recurrence of SCC (5/15), wound dehiscence (3/15), and excessive hemorrhage (1/15). Median (range) time to occurrence of postsurgical complications was 19 (5-205) days. There was no significant association (P > 0.05) between ocular diagnosis, age, anesthetic technique or the suture pattern used to close the skin postsurgically, and occurrence of postsurgical complications. CONCLUSIONS: Early clinical diagnosis of SCC by owners and veterinarians may prevent the need for exenteration. Owners should be made aware of the possible postsurgical complications following exenteration in cattle.

Systemic and ocular immune responses in cattle following intranasal vaccination with precipitated or partially solubilized recombinant Moraxella bovis cytotoxin adjuvanted with polyacrylic acid.

OBJECTIVE To evaluate changes in systemic and ocular antibody responses of steers following intranasal vaccination with precipitated or partially solubilized recombinant Moraxella bovis cytotoxin (MbxA). ANIMALS 13 Angus steers with ages ranging from 318 to 389 days and weights ranging from 352 to 437 kg. PROCEDURES Steers were assigned to receive 500 µg of a precipitated (MbxA-P; n = 5) or partially solubilized (MbxA-S; 5) recombinant MbxA subunit adjuvanted with polyacrylic acid. A control group (n = 3) received the adjuvant alone. Each steer received the assigned treatment (1 mL/nostril) on days 0 and 28. Serum and tear samples were collected on days 0 (before vaccination), 14, 28, 42, and 55. Changes in MbxA-neutralizing antibody titers and MbxA-specific IgG concentrations in serum and tears and changes in MbxA-specific IgA concentrations in tears were measured. RESULTS Mean fold changes in MbxA-specific IgG concentration in serum and tears and MbxA-neutralizing antibody titer in tears for the MbxA-P group were significantly greater than those for the MbxA-S and control groups. Mean serum MbxA-neutralizing antibody titer did not differ among the 3 groups. Although the mean fold change in tear MbxA-specific IgA concentration differed significantly among the groups in the overall analysis, post hoc comparisons failed to identify any significant pairwise differences. CONCLUSIONS AND CLINICAL RELEVANCE Systemic and ocular immune responses induced by intranasal administration of the MbxA-P vaccine were superior to those induced by the MbxA-S vaccine. Additional research is necessary to determine whether the MbxA-P vaccine can prevent naturally occurring infectious bovine keratoconjunctivitis.

Use of a percutaneous transabdominal catheter for management of obstructive urolithiasis in goats, sheep, and potbellied pigs: 69 cases (2000-2014).

OBJECTIVE To evaluate the use of a percutaneous transabdominal catheter (PTC) for urinary bladder drainage in goats, sheep, and potbellied pigs with obstructive urolithiasis. DESIGN Retrospective case series. ANIMALS 43 goats, 10 sheep, and 16 potbellied pigs (all males) with obstructive urolithiasis evaluated at the University of California-Davis Veterinary Medical Teaching Hospital. PROCEDURES Medical records of goats, sheep, and potbellied pigs examined because of obstructive urolithiasis from January 2000 through December 2014 were reviewed. Records of animals for which a standard PTC had been placed into the urinary bladder as part of disease management were selected. Data were collected regarding signalment, complications associated with PTC placement, and duration of PTC placement prior to removal. RESULTS 42 of 43 goats, 5 of 10 sheep, and all potbellied pigs were castrated. Median (range) duration of PTC placement was 2 (1 to 4) days for goats, 1 (1 to 4) day for sheep, and 1 (1 to 3) day for potbellied pigs. Complications associated with PTC placement included blockage of the catheter by urine sediment, perforation of the cecum, and migration of the catheter out of the urinary bladder. CONCLUSIONS AND CLINICAL RELEVANCE Placement of a PTC into the urinary bladder allowed for effective stabilization of goats, sheep, and potbellied pigs with obstructive urolithiasis while acid-base and electrolyte imbalances were corrected. Use of a PTC should be considered for urinary bladder drainage during medical management or prior to surgical management of obstructive urolithiasis for these species.

Infectious bovine keratoconjunctivitis (pinkeye).

As is the case for controlling other infectious livestock diseases, the most successful efforts to control infectious bovine keratoconjunctivitis (IBK) will include consideration of the host, the environment, herd management, and ongoing surveillance even after the immediate crisis has passed. Research over many years has led to the discovery of a variety of antibiotic treatments and antibiotic regimens that can be effective against IBK. The discoveries of Mor bovoculi and reports of IBK associated with Mycoplasma spp without concurrent Mor bovis or Mor bovoculi have raised new questions into the roles that other organisms may play in IBK pathogenesis.

Pharmacokinetics of ceftiofur crystalline-free acid following subcutaneous administration of a single dose to sheep.

OBJECTIVE: To determine the pharmacokinetics of ceftiofur crystalline-free acid (CCFA) following SC administration of a single dose to sheep. ANIMALS: 9 healthy adult female Suffolk-crossbred sheep. PROCEDURES: Each sheep was administered 6.6 mg of CCFA/kg, SC, in the cervical region once. Serial blood samples were collected at predetermined intervals for 14 days. Serum concentration of ceftiofur free-acid equivalents (CFAE) was determined by high-performance liquid chromatography. Pharmacokinetic parameters were determined by compartmental and noncompartmental methods. RESULTS: Pharmacokinetics for CCFA following SC administration in sheep was best described with a 1-compartment model. Mean ± SD area under the concentration-time curve from time 0 to infinity, peak serum concentration, and time to peak serum concentration were 206.6 ± 24.8 µâ€¢h/mL, 2.4 ± 0.5 µg/mL, and 23.1 ± 10.1 h, respectively. Serum CFAE concentrations ≥ 1 µg/mL (the target serum CFAE concentration for treatment of disease caused by Mannheimia haemolytica and Pasteurella multocida) were maintained for 2.6 to 4.9 days. No significant adverse reactions to CCFA administration were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that adequate therapeutic serum concentrations of CFAE for treatment of disease caused by M haemolytica and P multocida were achieved in sheep following SC administration of a single dose (6.6 mg/kg) of CCFA. Thus, CCFA might be useful for the treatment of common respiratory tract pathogens in sheep.

Ocular immune responses in steers following intranasal vaccination with recombinant Moraxella bovis cytotoxin adjuvanted with polyacrylic acid.

Infectious bovine keratoconjunctivitis (IBK) caused by Moraxella bovis is the most common eye disease of cattle. The pathogenesis of M. bovis requires the expression of pili that enable the organism to attach to the ocular surface and an RTX (repeats in the structural toxin) toxin (cytotoxin or hemolysin), which is cytotoxic to corneal epithelial cells. In this pilot study, ocular mucosal immune responses of steers were measured following intranasal (i.n.) vaccination with a recombinant M. bovis cytotoxin adjuvanted with polyacrylic acid. Beef steers were vaccinated with either 500 µg (n = 3) or 200 µg (n = 3) of recombinant M. bovis cytotoxin plus adjuvant. Control group steers (n = 2) were vaccinated with adjuvant alone, and all steers were given a booster on day 21. Antigen-specific tear IgA and tear IgG, tear cytotoxin-neutralizing antibody responses, and serum cytotoxin-neutralizing antibody responses were determined in samples collected prevaccination and on days 14, 28, 42, and 55. Changes in tear antigen-specific IgA levels from day 0 to days 28, 42, and 55 were significantly different between groups; however, in post hoc comparisons between individual group pairs at the tested time points, the differences were not significant. Our results suggest that i.n. vaccination of cattle with recombinant M. bovis cytotoxin adjuvanted with polyacrylic acid effects changes in ocular antigen-specific IgA concentrations. The use of intranasally administered recombinant M. bovis cytotoxin adjuvanted with polyacrylic acid could provide an alternative to parenteral vaccination of cattle for immunoprophylaxis against IBK.

Mineral composition of urinary calculi from potbellied pigs with urolithiasis: 50 cases (1982-2012).

OBJECTIVE: To determine the mineral composition and anatomic location of urinary calculi and to investigate sex and reproductive status as predisposing factors for development of urolithiasis in potbellied pigs. DESIGN: Retrospective case series SAMPLES: Urinary calculi from 50 purebred and crossbred potbellied pigs. PROCEDURES: Laboratory records for urinary calculi of potbellied pigs submitted to the University of California-Davis Stone Laboratory from 1982 through 2012 were reviewed. Mineral composition of calculi was determined by polarized light microscopy, infrared spectroscopy, and, in some cases, x-ray diffractometry. RESULTS: Of the 48 urinary calculi analyzed by infrared spectroscopy, 21 (44%) were composed primarily of amorphous magnesium calcium phosphate; another 9 (19%) were primarily composed of calcium phosphate in the form of apatite. Of 50 urinary calculi, 22 (44%), 14 (28%), 10 (20%), 3 (6%), and 1 (2%) were removed from the urinary bladder only, urethra, both urinary bladder and urethra, urine, and renal pelvis, respectively. Sex of 6 potbellied pigs was not recorded. For 44 urinary calculi, 41 (93%) were from males (11 sexually intact males and 30 castrated) and 3 (7%) were from females (2 sexually intact females and 1 spayed). Among males, 73% (30/41) of submissions were from castrated males. CONCLUSIONS AND CLINICAL RELEVANCE: In contrast to results from studies in commercial pigs, the most common composition of urinary calculi identified in purebred and crossbred potbellied pigs was amorphous magnesium calcium phosphate. Potential predisposing factors for urolithiasis in potbellied pigs may be similar to those for urolithiasis in commercial pigs. These include diet, urinary tract infections, and sex. Thus, prevention of urolithiasis should target these potential predisposing factors.

Gangrenous mastitis caused by Bacillus species in six goats.

CASE DESCRIPTION: 6 lactating dairy goats were examined because of acute mastitis. CLINICAL FINDINGS: Goats were considered to have endotoxemia on the basis of physical examination and clinicopathologic findings. The affected udder halves had gangrenous discolored distal portions with sharp demarcations from grossly normal tissue proximally. Udder secretions from the affected sides were serosanguineous in all cases. A Bacillus sp was isolated in pure cultures in all cases. In 1 case, the Bacillus sp was identified as Bacillus cereus. TREATMENT AND OUTCOME: Goats were treated for mastitis and endotoxemia with polyionic IV fluid therapy, systemic and intramammary antimicrobial administration, anti-inflammatory drug administration, and other supportive treatment. All goats survived to discharge. All except 1 goat had follow-up information available. The affected udder halves sloughed in 1 to 2 months following discharge. In subsequent lactations after the mastitis episodes, milk production in 2 of 5 goats was above the mean, as determined on the basis of Dairy Herd Improvement records, and 3 of 5 goats were voluntarily withdrawn from lactation. All 5 goats had successful kiddings after the Bacillus mastitis episode. CONCLUSIONS AND CLINICAL RELEVANCE: Bacillus sp should be considered as a causative agent in goats with gangrenous mastitis, especially when the Bacillus sp is isolated in a pure culture. Antimicrobial sensitivity testing is recommended for selection of an appropriate antimicrobial for treatment. Prognosis for survival appears to be good, although milk production may be decreased.