Molecular characteristics of new clonal complexes of Staphylococcus pseudintermedius from clinically normal dogs

Background: High prevalence of methicillin resistance among clinical isolates of Staphylococcus pseudintermedius obtained from dogs was reported in Seoul metropolitan area, South Korea. However, no information on genetic lineage and clonal spread is currently available.

Objective: The aim is to identify the genetic diversity of methicillin-resistant or -susceptible S. pseudintermedius (MRSP and MSSP, respectively) from healthy dogs.

Animals and methods: From 119 healthy dogs, 29 isolates consisting of 20 MRSP and 9 MSSP were collected from June 2013 to February 2014. Phenotypic features, antibiogram, multilocus sequence type (MLST), Staphylococcal cassette chromosome mec (SCCmec) type and spa gene type were analyzed.

Results: MLST showed 24 sequence types (STs), including 20 new STs that were genetically distinct from the previous STs in other geographic areas. SCCmec typing revealed that all isolates had SCCmec type V, a predominant type in North America. spa gene typing was successful in only 13 isolates (10 MRSP and 3 MSSP) and revealed two known types (t02 and t06), as well as one novel type (t73).

Conclusion: Our cumulative data indicate the presence of various populations of S. pseudintermedius in clinically normal dogs in Seoul metropolitan area.     

Investigation of cell-free DNA in canine plasma and its relation to disease

Background: DNA is released from dying cells during apoptosis and necrosis. This cell-free DNA (cfDNA) diffuses into the plasma where it can be measured. In humans, an increase in cfDNA correlates with disease severity and prognosis.

Objective: It was hypothesized that when DNA in canine plasma was measured by emission fluorometry without prior DNA extraction, the concentration of cfDNA would increase with disease severity.

Animals: The diseased population consisted of 97 client-owned dogs. The clinically normal population consisted of nine client-owned dogs presenting for ‘wellness screens’, and 15 colony-owned Harrier Hounds.

Methods: Plasma cfDNA was measured by fluorometry without prior DNA extraction. The effects of ex vivo storage conditions were evaluated in plasma from two clinically normal dogs. In all other dogs, plasma was separated within two hours of collection. The association between the cfDNA concentration in hospitalized dogs and a variety of clinical, clinicopathological and outcome variables was tested.

Results: The concentration of cfDNA was reliably measured when plasma was separated within two hours of blood collection. The diseased dogs had significantly higher cfDNA than clinically normal dogs (P < 0.001), and the more severe the disease, the higher the cfDNA when severity was categorized according to the American Society of Anesthesiologists (ASA) status (P < 0.001). Dogs that did not survive to discharge had significantly higher cfDNA concentrations than survivors (P = 0.02).

Conclusions/Clinical Importance: The concentration of cfDNA in the plasma of diseased dogs is associated with disease severity and prognosis. Measurement of canine cfDNA could be a useful non-specific disease indicator and prognostic tool.     

The occurrence of giant fibres in different muscles of two chicken genotypes

1. The occurrence of Giant Fibres (GF) in three muscles (Pectoralis major (PM), Iliotibialis lateralis and Semimembranosus) with different types of energy metabolism was studied in slow- and fast-growing chicken strains.

2. A total of 20 one-day-old Leghorn chicks (slow-growing) and 20 broiler (Ross 508) chicks (fast-growing) were reared to 100 and 45 d, respectively.

3. A small percentage of GF was seen in pre rigor muscle samples even at 3 min post mortem in both genotypes and in all muscle types studied.

4. From 3 min to 24 h post mortem GF increased both in Leghorn and broiler chickens but to a different extent according to muscle type and genotype.

5. The highest GF 24 h post mortem value was found in the PM muscles belonging to the fast-growing broiler line.

6. It was concluded that every type of muscle can develop GF, but this phenomenon is more evident in the PM especially in animals selected for increased growth rate.     

Encapsulated benzoic acid supplementation in broiler diets influences gut bacterial composition and activity

1. The present study investigated the effects of encapsulated benzoic acid (BA) supplementation in broiler feed on performance and gastrointestinal microbiota.

2. Eighty broilers were randomly divided into two groups. Birds in the control group were fed on maize–soybean-based diets. Birds in the treatment group were provided the same diet supplemented with 2 g/kg BA encapsulated in a vegetable oil matrix.

3. At the end of the trial (d 35), pH, bacterial composition and metabolites were determined in the crop, jejunum, ileum and caecum.

4. Growth performance variables and pH were not significantly different.

5. BA concentration decreased rapidly in the proximal gut. However, the treatment diet showed higher BA in the crop, jejunum, ileum and caecum.

6. Total lactate in the crop and D-lactate in the jejunum was higher in the BA treated group. Caecal total and branched chain fatty acids were decreased due to the treatment.

7. Lactobacilli populations were significantly altered by BA supplementation. A trend for increased lactobacilli was observed in the crop, while it became significant in the jejunum and ileum. Lactobacillus species responded differently to the treatment. Four of 5 measured Lactobacillus species, particularly in the ileum, followed the course observed for total lactobacilli; only Lactobacillus salivarius was not modified.

8. Correlation analysis showed that BA modified the intestinal microbiota. Lactobacilli correlated negatively to all studied clostridial clusters and enterobacteria. Clostridial clusters IV and XIVa were significantly increased in the jejunum, whereas only clostridial cluster XIVa was increased in the caecum.

9. Encapsulated BA modified the intestinal microbiota which can lead to the conclusion, that the main beneficial mode of action of BA in the gut appears to be the enhancement of lactic acid bacteria, which in turn may act as a vanguard against pathogens.     

Lipopolysaccharide reduces food passage rate from the crop by a prostaglandin-independent mechanism in chickens

1. We examined the effect of lipopolysaccharide (LPS), a component of Gram-negative bacteria, on food passage in the digestive tract of chickens (Gallus gallus) in order to clarify whether bacterial infection affects food passage in birds.

2. Food passage in the crop was significantly reduced by intraperitoneal (IP) injection of LPS while it did not affect the number of defecations, suggesting that LPS may affect food passage only in the upper digestive tract.

3. Similar to LPS, prostaglandin E2 (PGE2), one of the mediators of LPS, also reduced crop-emptying rate in chickens while it had no effect on the number of defecations.

4. Pretreatment with indomethacin, which is an inhibitor of cyclooxygenase (COX), a prostaglandin synthase, had no effect on LPS-induced inhibition of crop emptying.

5. IP injection of LPS did not affect the mRNA expression of COX2 in the upper digestive tract of chickens.

6. It is therefore likely that LPS and PGE2 reduced food passage rate in the crop by a prostaglandin-independent pathway in chickens.     

Effects of dietary supplementation with Gynura procumbens (Merr.) on egg yolk cholesterol,excreta microflora and laying hen performance

1. The present study investigated the effects of dietary supplementation with Gynura procumbens on egg yolk and serum cholesterol and triglycerides, excreta microflora, laying performance and egg quality.

2. A total of 160 Hy-Line Brown layers (45 weeks old) were randomly assigned into 4 treatments on the basis of laying performance. Each treatment had 4 replicates with 10 birds each.

3. Dietary treatments were basal diet supplemented with 0 (control), 2.5, 5.0 and 7.5 g/kg diet G. procumbens during 56-d feeding period.

4. Serum (d 21, 42 and 56) and egg yolk (d 28, 42 and 56) cholesterol and triglycerides concentrations were linearly reduced with increasing dietary concentrations of G. procumbens.

5. Increasing dietary concentrations of G. procumbens linearly reduced the excreta total anaerobic bacteria (d 28), Clostridium sp. and Escherichia coli (d 28 and 56) populations.

6. Overall egg production and egg mass were linearly increased, and overall feed efficiency was linearly improved with increase in dietary G. procumbens.

7. Dietary increasing concentrations of G. procumbens linearly improved egg yolk colour (d 28 and 56) and breaking strength of eggs (d 56).

8. The results obtained in the present experiment indicate that dietary supplementation with G. procumbens could reduce the egg yolk cholesterol, suppresses harmful excreta microflora and improves layers performance.     

Comparison of the productive perform. Ances of the Sinai Bedouin fowl,the white leghorn and their crossbreds: Study under laboratory conditions

1. A comparison of the productive performances of the Sinai Bedouin fowl (from the Sinai desert), the commercial White Leghorn and their reciprocal crossbreds was made under uniform normal conditions.

2. The Sinai produced significantly fewer, smaller eggs, resulting in lower egg mass output (g/bird d), than the Leghorn and the crossbreds.

3. Egg weight of both crossbreds was intermediate between Sinai and Leghorn but laying rate was closer to that of the Leghorn.

4. Differences in egg mass output apparent at 8 to 10 months of age decreased considerably with age.

5. These findings suggest that selection or crossbreeding of the Sinai might improve productive performance while maintaining improved eggshell quality.     

The effects of restricted feeding on adrenal cortical activity in the immature domestic fowl

1. The effect of reducing food intake to 75% of the ad libitum intake was determined from hatching to 8 weeks in young Light Sussex chickens.

2. Restricted birds were lighter throughout the experiment.

3. Relative adrenal weight tended to be greater in restricted birds but the difference decreased with time.

4. There was no depletion of adrenal cholesterol: from week 5 there was a significantly greater amount in the adrenals of restricted birds.

5. After 1 week of restriction plasma corticosterone concentration was 73% greater than in controls. It decreased progressively, falling within the normal range at 5 weeks.

6. Restricted birds were hypoglycaemic from weeks 2 to 7 and hyper‐lipacidaemic throughout. A negative correlation between plasma glucose and free fatty acids was found.     

Molecular serotyping and antimicrobial resistance profiles of Actinobacillus pleuropneumoniae isolated from pigs in South Korea

Background: Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PP).

Objective: Serotypes and antimicrobial resistance patterns in APP isolates from pigs in Korea were examined.

Methods: Sixty-five APP isolates were genetically serotyped using standard and multiplex PCR (polymerase chain reaction). Antimicrobial susceptibilities were tested using the standardized disk-agar method. PCR was used to detect β-lactam, gentamicin and tetracycline-resistance genes. The random amplified polymorphic DNA (RAPD) patterns were determined by PCR.

Results: Korean pigs predominantly carried APP serotypes 1 and 5. Among 65 isolates, one isolate was sensitive to all 12 antimicrobials tested in this study. Sixty-two isolates was resistant to tetracycline and 53 isolates carried one or five genes including tet(B), tet(A), tet(H), tet(M)/tet(O), tet(C), tet(G) and/or tet(L)-1 markers. Among 64 strains, 9% and 26.6% were resistance to 10 and three or more antimicrobials, respectively. Thirteen different antimicrobial resistance patterns were observed and RAPD analysis revealed a separation of the isolates into two clusters: cluster II (6 strains resistant to 10 antimicrobials) and cluster I (the other 59 strains).

Conclusion: Results show that APP serotypes 1 and 5 are the most common in Korea, and multi-drug resistant strains are prevalent. RAPD analysis demonstrated that six isolates resistant to 10 antimicrobials belonged to the same cluster.     

Gene expression profile of IGF1 and MSTN mRNA and their correlation with carcass traits in different breeds of geese at 70 d of age

1. The expression of insulin-like growth factor-1 (IGF1) and myostatin (MSTN) mRNA in breast and leg muscle was quantified in 70-d-old Taihu and Wanxi geese by using a Multiplex Competitive Fluorescent–PCR method and the correlations between mRNA levels and carcass traits were analysed.

2. IGF1 mRNA expression in breast muscle in Taihu geese was significantly higher than that in Wanxi geese and the MSTN mRNA level in leg muscle in Taihu geese was significantly higher than that in Wanxi geese.

3. There was no significant difference in breast muscle MSTN or leg muscle IGF1 mRNA expression between the two breeds.

4. Within the same breed, the IGF1 mRNA expression in leg muscle of male geese was significantly higher than that in female geese, and MSTN mRNA expression in leg muscle was significantly higher than that in breast muscle.

5. There was no difference in the IGF1 mRNA expression between tissues.

6. There was a positive correlation between IGF1 mRNA and MSTN mRNA and a negative correlation between IGF1 mRNA expression of breast muscle and leg muscle ratio.

7. In Wanxi geese, MSTN mRNA expression in leg muscle was negatively associated with body weight and leg muscle weight.     

Prevalence of and risk factors for Campylobacter colonisation in broiler flocks at the end of the rearing period in France

1. A study was conducted to estimate the prevalence and quantification by species of Campylobacter infection in broiler flocks at the end of the rearing period and to identify associated risk factors.

2. A questionnaire about the rearing period was completed and caecal samples were collected from 121 broiler flocks in Brittany, France, during 2008.

3. Campylobacter was isolated in 87 out of 121 flocks – a prevalence of 71.9% (95% CI, 63.7–80.1%), including 40.5% of Campylobacter jejuni and 29.8% of Campylobacter coli.

4. The average concentration, in positive flocks, was 7.96 log₁₀ cfu/g and ranged from 3.15 to 10.32 log₁₀ cfu/g.

5. The average concentration by species was: 7.57 log₁₀ cfu/g for C. jejuni and 8.44 log₁₀ cfu/g for C. coli.

6. There was a seasonal effect, with increased risk of Campylobacter colonisation in June, July and August (odds ratio (OR) = 9.59, 95% CI 1.15–79.75).

7. The other factors, associated with lower risk of Campylobacter colonisation, were the acidification of drinking water (OR = 0.33, 95% CI 0.13–0.86), antibiotic treatment at the beginning of the rearing period (OR = 0.20, 95% CI 0.07–0.55) and rodent control around the house (OR = 0.18, 95% CI 0.03–0.95).

8. The results show that hygiene practices and biosecurity measures could lead to a reduction in Campylobacter colonisation.     

Protein and energy metabolism in two lines of chickens selected for growth on high or low protein diets

1. Genetic adaptation was investigated in broilers selected for seven generations on a normal (A) or a low (B) protein diet.

2. Protein and energy metabolism were studied in males from these selected lines fed on a diet of intermediate protein content.

3. All selected birds retained more nitrogen than those studied 10 years previously.

4. There was no difference in nitrogen retention between groups, although relative growth rate of group B birds was higher.

5. Heat productions relative to gross energy intake were 0.38 (group B) and 045 (group A). Energy retentions relative to gross energy intake were 0.39 (group B) and 0.35 (group A); the difference being primarily due to higher fat retention in group B.

6. Using a common maintenance requirement for metabolisable energy, group B utilised metabolisable energy for growth (0.78) better than did group A (0.71).

7. At 53 d of age plasma glucose (10%) and insulin (50%) were higher in group B than in group A.     

A 31P topical magnetic resonance study of embryonic development in hens' eggs

1. A ³¹P topical magnetic resonance study of whole chicken's eggs in vivo is described.

2. Resonances from adenosine triphosphate, phosphocreatine, inorganic phosphate and phosphorous storage protein were observed. These changed in relative intensity as the embryo developed.

3. No ill effects due to exposure to radiofrequency radiation or magnetic fields were observed.

4. It is concluded that topical magnetic resonance can make a useful contribution to the study of embryonic development in avian eggs.     

A mathematical representation of the Ovulatory cycle of the domestic hen

1. The ovulatory cycle of the domestic hen (Gallus domesticus) was postulated to be the result of the interaction of two independent systems.

2. A circadian system was postulated to control the restriction of ovulation to an 8‐h period of the day under conventional 14 h light: 10 h dark regimes.

3. The final phase of follicular maturation was postulated to commence after ovulation of the preceding ovum in the hierarchy.

4. Ovulation was postulated to occur when a mature follicle was present in the ovary during the appropriate phase of the circadian‐linked system.

5. The predicted times of oviposition were within the standard error of the observed times of oviposition under 21‐, 24‐ and 28‐h photoschedules.

6. It was concluded that this hypothesis for the control of the ovulatory cycle of the hen is consistent with current knowledge.     

Atrioventricular valvular anomalies and their role in the etiopathogenesis of cardiorespiratory syndrome in farmed common foxes (Vulpes vulpes)

Background: Cardiorespiratory syndrome of common foxes is associated with a mortality rate ranging from 2.1% to 20%.

Objective: The aim of this study was to analyze the prevalence of cardiac abnormalities in common foxes (Vulpes vulpes) from Polish farms with a history of cardiorespiratory syndrome.

Animals and methods: The prevalence of cardiac abnormalities in common foxes from a Polish farm with a history of cardiorespiratory syndrome was assessed as well as morphological examination of 60 heart specimens from clinically healthy animals. In addition, 38 foxes were examined echocardiographically and subjected to postmortem examination.

Results: Atrioventricular valvular abnormalities were found in 57 out of the 98 (58%) analyzed hearts. The abnormalities of the mitral valve documented in more than 20% of the foxes in involved tendinous chords (completely lacking or shortened), papillary muscles and mitral cusps associated with both insufficiency and stenosis of the left atrioventricular orifice. Abnormalities of the tricuspid valve included significant shortening of the tendinous chords and thickening of the valve cusps with the impairment of their mobility. The results of the echocardiographic and postmortem examination were consistent in 79% of the cases. The specimens collected from animals with and without atrioventricular valvular anomalies did not differ significantly in terms of cardiomyocyte width, number of inflammatory cells, adipose tissue content and presence of polychromatic cardiomyocytes.

Conclusion: Congenital atrioventricular valvular defects may be involved in the etiology of cardiorespiratory syndrome in common foxes, and echocardiography can be used as a measure of stock's health and a criterion for selection for mating.     

Isolation and genotyping of Campylobacter species from kiwi (Apteryx spp.) in captivity: implications for transmission to and from humans

Aims: To investigate the presence of Campylobacter spp. in captive kiwi (Apteryx spp.) and compare their genotypic profiles with those of human and animal origin, in order to assess their potential for zoonotic or zooanthroponotic transmission.

Methods: Conventional selective enrichment and filter-based isolation methods were applied to isolate Campylobacter spp. from fresh faecal samples from 12 North Island brown kiwi (Apteryx mantelli) and one great spotted kiwi (A. haastii), housed in one of five different areas in a kiwi sanctuary in Christchurch, New Zealand. Isolates were identified using multiplex PCR and 16S rRNA gene sequencing. High-resolution rapid genotyping using multiplex ligation-dependant probe amplification-based binary typing (MBiT) was applied and profiles compared with similar results from 2,165 Campylobacter spp. isolates contained in a database derived from human clinical, veterinary and environmental samples.

Results: One isolate of C. jejuni, and one belonging to the C. lari phylogenetic group were recovered from faeces from two kiwi. High-resolution rapid genotyping by MBiT demonstrated these to be indistinguishable from isolates obtained previously from human cases of diarrhoea, and others from chicken, cattle, sheep and water.

Conclusions: These data provide evidence for potential zoonotic or zooanthroponotic transmission of Campylobacter spp. in kiwi with implications for management of birds kept in captivity. We believe this is the first formal report of C. jejuni and a C. lari-like organism in kiwi.

Abbreviations: MBiT: Multiplex ligation-dependant probe amplification-based binary typing     

Development of two surgical approaches to the pituitary gland in the Horse

Background: Current treatment of equine pituitary pars intermedia dysfunction (PPID) requires daily oral medication. Minimally invasive surgical palliation of this condition is appealing as a single treatment to alleviate the clinical signs of disease, dramatically improving the welfare of the horse.

Objective: To develop a surgical approach to the equine pituitary gland, for subsequent treatment of PPID.

Study design: A cadaver study to develop methodology and a terminal procedure under anaesthesia in the most promising techniques.

Animals and methods: Four surgical approaches to the pituitary gland were investigated in cadaver animals. A ventral trans-basispheniodal osteotomy and a minimally invasive intravenous approach via the ventral cavernous sinus progressed to live horse trials.

Results: Technical complications prevented the myeloscopic and trans-sphenopalatine sinus techniques from being successful. The ventral basisphenoidal osteotomy was repeatable and has potential if an intra-operative imaging guidance system could be employed. The minimally invasive approach was repeatable, atraumatic and relatively inexpensive.

Conclusions: A minimally invasive surgical approach to the equine pituitary gland is possible and allows for needle placement within the target tissue. More work is necessary to determine what that treatment might be, but repeatable access to the gland has been obtained, which is a promising step.     

Evaluation of bone strength,keel bone status,plumage condition and egg quality of two layer lines kept in small group housing systems

1. The aim of the present study was to determine the influence of large (54 or 60) and small (36 or 40) group sizes and tiers of the small group housing system “Eurovent German” on tibia and humerus bone breaking strength, keel bone status, plumage condition and egg quality for two commercial layer lines, Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB), at the same stocking density (890 or 830 cm²/bird).

2. In 4 consecutive trials, 4752 hens were recorded for keel bone status. Evaluation of plumage condition was made for 1440 hens and bone breaking strength was recorded for 1200 hens. A total of 4962 eggs were analysed for internal and external egg quality traits. Analyses involved 30 small group compartments per trial.

3. The layer line had a much more pronounced influence on humerus breaking strength than on tibia breaking strength.

4. Plumage condition, particularly on the neck, was positively correlated with humerus breaking strength in both layer lines.

5. An average of 34% of LB and 23% of LSL hens showed keel bone deformities, with higher proportions of slight deformities.

6. Slight keel bone deformities, rather than moderate to severe, increased significantly during the laying period.

7. Stocking density had no influence on bone breaking strength, keel bone status and egg quality traits.

8. LB layers had a 1.4-fold higher humerus, but only a 1.06-fold higher tibia breaking strength compared to LSL layers.

9. Tibia breaking strength was significantly affected by the interaction of group size and layer line. LSL layers in small groups had lower tibia breaking strengths than those of the large groups.     

Grass meal as an ingredient in diets for broiler chickens

1. Six diets of equal energy and nitrogen contents containing between 0 (control) and 125 g grass meal/kg were each fed to 4 groups of 42 male and 4 groups of 42 female broiler chicks, in floor pens, from 0 to 56 d of age.

2. Increments of 25 g grass meal/kg and 7.3 g maize oil/kg replaced a mixture of soyabean, wheat and barley meals in the control diet.

3. Gain: food ratio (y) of the birds decreased linearly as dietary grass meal content (x) increased such that y = 0.4295 ? 0.0032x.

4. Carcass analyses indicated that the decrease in gain : food ratio was caused by less deposition of body fat.

5. Skin colour became significantly yellower as the dietary grass meal content increased.