Effect of dietary supplementation with yeast cell wall extracts on performance and gut response in broiler chickens.

BACKGROUND: The dietary supplementation of yeast cell wall extracts (YCW) has been found to reduce pathogenic bacteria load, promote immunoglobulin production, prevent diseases by pro-inflammatory responses, and alter gut microbiota composition. This study evaluated growth and slaughter results, health, gut morphology, immune status and gut transcriptome of 576 male chickens fed two diets, i.e. C (control) or Y (with 250-500 g/t of YCW fractions according to the growth period). At 21 and 42 d the jejunum of 12 chickens per diet were sampled and stained with hematoxylin/eosin for morphometric evaluation, with Alcian-PAS for goblet cells, and antibodies against CD3+ intraepithelial T-cells and CD45+ intraepithelial leukocytes. The jejunum sampled at 42 d were also used for whole-transcriptome profiling. RESULTS: Dietary YCW supplementation did not affect final live weight, whereas it decreased feed intake (114 to 111 g/d; P ≤ 0.10) and improved feed conversion (1.74 to 1.70; P ≤ 0.01). Regarding the gut, YCW supplementation tended to increase villi height (P = 0.07); it also increased the number of goblet cells and reduced the density of CD45+ cells compared to diet C (P < 0.001). In the gut transcriptome, four genes were expressed more in broilers fed diet Y compared to diet C, i.e. cytochrome P450, family 2, subfamily C, polypeptide 23b (CYP2C23B), tetratricopeptide repeat domain 9 (TTC9), basic helix-loop-helix family member e41 (BHLHE41), and the metalloreductase STEAP4. Only one gene set (HES_PATHWAY) was significantly enriched among the transcripts more expressed in broilers fed diet Y. However, a total of 41 gene sets were significantly over-represented among genes up-regulated in control broilers. Notably, several enriched gene sets are implicated in immune functions and related to NF-κB signaling, apoptosis, and interferon signals. CONCLUSIONS: The dietary YCW supplementation improved broiler growth performance, increased gut glycoconjugate secretion and reduced the inflammatory status together with differences in the gut transcriptome, which can be considered useful to improve animal welfare and health under the challenging conditions of intensive rearing systems in broiler chickens.

Evidence of Vasculogenic Mimicry in a Palpebral Melanocytoma in a Dog.

A 7-year-old neutered female Doberman pinscher was presented with a palpebral nodule on the haired eyelid of the left eye. The nodule was removed surgically. Microscopically, the nodule was consistent with eyelid melanocytoma. The tumour was characterized by the presence of numerous lacunar and slit-like spaces filled by erythrocytes and interspersed throughout the neoplastic melanocytes. Immunohistochemically, these spaces were lined by cells expressing PNL2, but the cells were negative for factor VIII and CD31. [corrected] These findings were consistent with neoplastic melanocytes without endothelial cell participation. This feature was interpreted as 'vasculogenic mimicry', a mechanism of tumour angiogenesis that is well-recognized in human melanomas, but has not yet been reported in melanomas in animals.

The impact of toceranib, piroxicam and thalidomide with or without hypofractionated radiation therapy on clinical outcome in dogs with inflammatory mammary carcinoma.

In dogs, inflammatory mammary carcinoma is a clinicopathological entity characterized by rapid progression and aggressive behavior from onset of disease. Reported median survival time is short, with no effective treatment options. The aims of this prospective, noncontrolled clinical trial were to investigate outcome variables and safety profile of toceranib, thalidomide and piroxicam with or without hypofractionated radiation therapy in dogs with measurable histologically confirmed inflammatory mammary carcinoma that underwent a complete staging. Eighteen dogs were enrolled: 14 received medical treatment, and 4 were treated with hypofractionated radiation therapy and medical therapy. Overall, median time to progression was 34 days and median survival time was 109 days. In dogs treated with medical therapy, overall response rate was 21%, and clinical benefit rate (CBR) was 64%; median time to progression was 28 days and median survival time was 59 days. In dogs receiving medical therapy and undergoing radiation therapy, overall response rate and clinical benefit rate were 100%, with significantly longer time to progression (156 days) and survival time (180 days). Overall, treatment was well tolerated, with mild gastrointestinal and dermatological adverse events. Although the optimal treatment to this disease remains uncertain, the current approach consisting of systemic anti-angiogenic drugs with or without hypofractionated radiation therapy, provided clinical benefit in a significant proportion of dogs and should, therefore, be further explored.

Impact of sexual maturity on the welfare of immunocastrated v. entire heavy female pigs.

During oestrus, fattening female pigs are more prone to lameness, fractures and wounds due to mounting and agonistic behaviours of penmates. This study assessed the effect of sexual maturity on the behaviour and welfare of heavy female pigs slaughtered at 36 weeks of age (180±10 kg) for dry-cured ham production. An immunocastrated control group was used for comparison. In all, 56 15-week-old female pigs, individually identifiable by back tattoos were equally distributed among four pens. All animals from two pens were subject to a three-dose immunocastration schedule at 16, 20 and 32 weeks of age. Skin lesions and behaviours were assessed at 18, 23, 28, 33 and 36 weeks of age. A blood sample was collected at 20, 24, 28 and 32 weeks of age for assessing health/stress parameters and GnRH antibodies. At slaughter, ovaries were weighed, measured and histologically examined; stomachs, carcasses and lungs were scored for lesions and a further blood sample was taken. Immunocastrated pigs did not significantly differ from controls in growth rate, feed efficiency and slaughter performances (lung score, gastric score, backfat thickness). However, they showed a lower frequency of aggressive interactions at 33 and 36 weeks, lower front lesions at 28 weeks, but higher at 30 weeks; a lower haptoglobin level at 28 weeks, a lower level of cortisol and back lesions at slaughter (36 weeks). These findings suggest a low, yet not negligible, impact of sexual maturity on the welfare of heavy female pigs.

Frequency of DEA 1 antigen in 1037 mongrel and PUREBREED dogs in ITALY.

BACKGROUND: The prevalence of dog erythrocyte antigen (DEA 1) in canine population is approximately 40-60%. Often data are limited to a small number of breeds and/or dogs. The aims of this study were to evaluate frequency of DEA 1 in a large population of purebred and mongrel dogs including Italian native breeds and to recognize a possible association between DEA 1 and breed, sex, and genetic and phenotypical/functional classifications of breeds. Frequencies of DEA 1 blood group collected from screened/enrolled blood donors and from healthy and sick dogs were retrospectively evaluated. The breed and the sex were recorded when available. DEA 1 blood typing was assessed by immunocromatographic test on K3EDTA blood samples. The prevalence of DEA 1 antigen was statistically related to breed, gender, Fédération Cynologique Internationale (FCI) and genotypic grouping. RESULTS: Sixty-two per cent dogs resulted DEA 1+ and 38% DEA 1-. DEA 1- was statistically associated with Dogo Argentino, Dobermann, German Shepherd, Boxer, Corso dogs, the molossian dogs, the FCI group 1, 2 and 3 and the genetic groups "working dogs" and "mastiff". DEA 1+ was statistically associated with Rottweiler, Briquet Griffon Vendéen, Bernese mountain dog, Golden Retriever, the hunting breeds, the FCI group 4, 6, 7 and 8 and the genetic groups "scent hounds" and "retrievers". No gender association was observed. CONCLUSIONS: Data obtained by this work may be clinically useful to drive blood donor enrollment and selection among different breeds.

Hepatitis E virus infection in North Italy: high seroprevalence in swine herds and increased risk for swine workers.

We determined the hepatitis E virus (HEV) seroprevalence and detection rate in commercial swine herds in Italy's utmost pig-rich area, and assessed HEV seropositivity risk in humans as a function of occupational exposure to pigs, diet, foreign travel, medical history and hunting activities. During 2011-2014, 2700 sera from 300 swine herds were tested for anti-HEV IgG. HEV RNA was searched in 959 faecal pools from HEV-seropositive herds and in liver/bile/muscle samples from 179 pigs from HEV-positive herds. A cohort study of HEV seropositivity in swine workers (n = 149) was also performed using two comparison groups of people unexposed to swine: omnivores (n = 121) and vegetarians/vegans (n = 115). Herd-level seroprevalence was 75·6% and was highest in farrow-to-feeder herds (81·6%). Twenty-six out of 105 (24·8%) herds had HEV-positive faecal samples (25 HEV-3, one HEV-4). Only one bile sample tested positive. HEV seropositivity was 12·3% in swine workers, 0·9% in omnivores and 3·0% in vegetarians/vegans. Factors significantly associated with HEV seropositivity were occupational exposure to pigs, travel to Africa and increased swine workers' age. We concluded that HEV is widespread in Italian swine herds and HEV-4 circulation is alarming given its pathogenicity, with those occupationally exposed to pigs being at increased risk of HEV seropositivity.

Effect of age on the occurrence of muscle fiber degeneration associated with myopathies in broiler chickens submitted to feed restriction.

To evaluate muscle fiber degeneration (MFD) associated with white striping and wooden breast, pectoralis major of 192 broilers differing for genotype (standard vs. high breast yield), gender, and feeding regime (ad libitum vs. restricted rate 80% from 13 to 21 d of age) were sampled at 14, 21, 28, 35, and 46 d of age for histological analyses by hematoxylin and eosin (H&E) staining to evaluate tissue morphology, Masson's trichrome to identify collagen presence, and Oil red and Nile blue for lipid presence. Microvessels (diameter ≤15 µm), nuclei positive to anti-cleaved lamin A and monoclonal proliferating cell nuclear antigen (PCNA) antisera were counted to assess apoptotic and regenerative processes, respectively. Significant differences were found according to feeding system, age, and their interactions. The frequency of chickens with MFD was higher with ad libitum than restricted feeding (75.0% vs. 62.5%; P = 0.01) and increased with age (18.8%, 28.1%, 75.1%, 96.9%, and 96.9% at 14, 21, 28, 35, and 46 d). However, at 14 d a similar frequency (18.8%) was found in all broilers; at 21 d, MFD occurred more in broilers fed ad libitum than in those under restriction (50.0% vs. 6.3%; P < 0.01); at 28 d differences were reduced (87.5% vs. 62.5%; P  = 0.10) to disappear by 35 (100% and 93.8%) and 46 d (96.9% and 96.9%). The number of microvessels decreased with age (20.7 to 9.46; P < 0.001) and the number of nuclei positive to the anti-cleaved lamin A antibody increased. At histology, MFD at 46 d corresponded to loss of typical cross striations, massive necrotic process, degenerating fibers surrounded by inflammatory cells, scattered fibers in an abundant collagen-rich connective tissue, numerous adipose cells; necrotic fibers showed a high percentage of apoptotic nuclei, and regenerating fibers appeared positive to anti-PCNA antibody. In conclusion, MFD soon occurred after 2 wk of growth and increased dramatically within 28 d. Early feed restriction reduced MFD as long as animals were restricted, but no residual effect was recorded after re-alimentation.

Clostridial co-infection episodes in commercial laying hens.

The present report describes two outbreaks of serious enteritis in commercial laying hens where Clostridium perfringens and Clostridium colinum were simultaneously detected. At the age of 44 and 31 weeks, two laying hen flocks showed an increase of the mortality rate and a worsening of productive performance. Post-mortem examination revealed intestinal necrotic-haemorrhagic ulcerations and hepatic focal necrosis. The bacteriological examination yielded the isolation of C. colinum and C. perfringens toxin type A, NetB positive. In one outbreak, C. colinum was detected also by polymerase chain reaction in all the intestines of affected birds. In laying hens, C. colinum has never been isolated but only suspected as the causative agent of a slight enteric disease called duodenal focal necrosis. The present case report was characterized by severe enteritis presumably due to the synergistic effect of C. colinum and C. perfringens.

Identification of undeclared sources of animal origin in canine dry foods used in dietary elimination trials.

Failure to respond to commercial limited antigen diets can occur in dogs kept on a dietary trial for the diagnosis of adverse food reaction (AFR). The aim of this study was to assess twelve canine dry limited antigen diets (eleven novel protein diets and one hydrolysed diet) for potential contamination by ingredients of animal origin not mentioned on the label. The validity of the two methods adopted for the detection of such food antigens was also evaluated. Each dietary product was analysed by microscopy analysis using the official method described in Commission Regulation EC 152/2009 with the aim of identifying bone fragments of different zoological classes (mammalian, avian and fish) and by polymerase chain reaction (PCR) for the identification of DNA of animal origin. Discrepancies between the results obtained by PCR and/or microscopy analysis and the ingredients listed on pet food packages were found. Only in two pet foods did the results of both analyses match the ingredients listed on the label. In the remaining ten samples, microscopy detected bone fragments from one or two unpredicted zoological classes, revealing avian fragments in six of ten samples followed by those of fish in five of ten and mammalian fragments in four of ten. In two samples, microscopy analysis identified a contamination that would have otherwise passed unobserved if only PCR had been used. However, PCR confirmed the presence of all the zoological classes detected by microscopy and also identified the DNA of an additional unexpected zoological class in two samples. Dogs might fail to respond to commercial limited antigen diets because such diets are contaminated with potential allergens. Both PCR and microscopy analysis are required to guarantee the absence of undeclared animal sources in pet foods. Before ruling out AFR, a novel protein home-made diet should be considered if the dog is unresponsive to a commercial regimen.

Expression of 8-OHdG in Zosterisessor ophiocephalus from the Venetian lagoon, Italy.

The aim of the present work was to evaluate the expression of 8-OHdG (8-hydroxydeoxyguanosine) in the benthic fish Zosterisessor ophiocephalus collected in two differently polluted sites of the Venetian lagoon (Porto Marghera and Caroman). We compared our data on 8-OHdG with those of CYP1A (Cytochrome P450, family 1, subfamily A, polypeptide 1), which is a well known biomarker for detoxification of contaminants. Immunohistochemistry with an antibody to 8-OHdG showed immunopositivity in nuclei of hepatocytes as well as in melanomacrophage centres of spleen and kidney, whereas an anti-CYP1A antibody exhibited positive immunostaining in the liver, kidney and ovary. The liver of males showed higher expression of both proteins than females. In animals from Porto Marghera site, the enzymatic assay for 8-OHdG exhibited higher levels in liver of males than in females. Western Blot analysis using the antibody anti-CYP1A recognized the presence of a band of about 60 kDa in the liver of males and females. Males exhibited a strong band, whereas in females the band showed a lower intensity. By using Real-Time PCR, the mRNA expression of CYP1A did not show any differences between males and females from each site, but it was at borderline significance level. Comparing the two sites, mRNA expression of CYP1A was significantly higher in the liver of both males and females from Porto Marghera than that of Caroman. The present data suggest that pollutants are bio-available as demonstrated by our biomarker analyses and may have a harmful effect on aquatic organisms such as Z. ophiocephalus. We report that the highest levels of hepatic 8-OHdG and CYP1A expression were detected in males, showing clear gender specificity.

Expression of heat shock protein 70 in the liver of extensively and intensively kept heavy pigs.

The objective of this work was to investigate the expression of heat shock protein 70 (HSP70) by Western blot (WB) in swine liver. Subsequently, the study aimed to apply this method to two experimental groups of heavy pigs raised in different confinement systems: intensive/indoor (Group A) and extensive/outdoor (Group B). Thirty-six crossbred commercial heavy pigs were divided as follows: Group A (eight castrated males and eight females) was equally distributed into two single-sex indoor pens (1.02 m²/pig); Group B (11 castrated males and nine females) was kept in one single (partially grassy and partially wooded) open area of about 6000 m². Group A was slaughtered at 41 weeks of age (170 ± 9 kg) and Group B at 48 weeks of age (172 ± 13 kg). At the abattoir the livers of all the animals were collected and analyzed by WB assay in order to quantify the levels of HSP70. Moreover, a further liver sample was taken from the same animals in order to investigate the cellular localization of HSP70 by immunohistochemistry (IHC). The interaction between sex and group resulted statistically significant (P = 0.001). When stratified by sex, Group A showed significantly higher HSP70 values compared with Group B for both male and female subjects (P < 0.001). Stratifying by group, males showed significantly higher HSP70 values than females in Group A (P < 0.001), whereas no statistical differences were observed between sexes for Group B (P = 0.653). The IHC results evidenced cytoplasmic immunoreactivity in a granular pattern in both groups. The different expression pattern observed by WB could prove to be a useful tool in the assessment of pig health and welfare.

Expression of the aryl hydrocarbon receptor pathway and cyclooxygenase-2 in dog tumors.

In humans, the aryl hydrocarbon receptor (AHR) gene battery constitutes a set of contaminant-responsive genes, which have been recently shown to be involved in the regulation of several patho-physiological conditions, including tumorigenesis. As the domestic dog represents a valuable animal model in comparative oncology, mRNA levels of cytochromes P450 1A1, 1A2 and 1B1 (CYP1A1, 1A2 and 1B1), AHR, AHR nuclear translocator (ARNT), AHR repressor (AHRR, whose partial sequence was here obtained) and cyclooxygenase-2 (COX2) were measured in dog control tissues (liver, skin, mammary gland and bone), in 47 mast cell tumors (MCTs), 32 mammary tumors (MTs), 5 osteosarcoma (OSA) and related surgical margins. Target genes were constitutively expressed in the dog, confirming the available human data. Furthermore, their pattern of expression in tumor biopsies was comparable to that already described in a variety of human cancers; in particular, both AHR and COX2 genes were up-regulated and positively correlated, while CYP1A1 and CYP1A2 mRNAs were generally poorly expressed. This work demonstrated for the first time that target mRNAs are expressed in neoplastic tissues of dogs, thereby increasing the knowledge about dog cancer biology and confirming this species as an useful animal model for comparative studies on human oncology.

Expression of Ki67, BCL-2, and COX-2 in canine cutaneous mast cell tumors: association with grading and prognosis.

The expression of Ki67, BCL-2, and COX-2 was investigated in 53 canine cutaneous mast cell tumors (MCTs) by immunohistochemistry and quantitative real time polymerase chain reaction (qPCR) to evaluate their prognostic significance and the association with the histologic grading and the mitotic index (MI). MCTs were graded according to the Patnaik grading system and the novel 2-tier grading system proposed by Kiupel. The numbers of mitotic figures/10 high-power fields (MI) were counted. Both grading systems were significantly associated with prognosis. The Patnaik grading was of limited prognostic value for grade 2 MCTs, with 23% being associated with mortality. The concordance among pathologists was strongly improved by the application of the 2-tier grading system, and 71% of high-grade MCTs were associated with a high mortality rate. MI and Ki67 protein expression were significantly associated with grading and survival. No significant association between BCL-2 protein expression and either grading system or health status was observed. BCL-2 mRNA expression was significantly higher in grade 2 than in grade 1 MCTs, while no statistically significant differences were detected between low- and high-grade MCTs. The increased BCL-2 mRNA level was significantly associated with increased mortality rate. The COX-2 protein expression was detected in 78% of the MCTs investigated. However, neither association with the tumor grade nor with the health status was observed. COX-2 mRNA was significantly up-regulated in MCTs compared to surgical margins and control skin tissue, but it was neither associated with tumor grade nor with survival.

Expression of matrix metalloproteinases, tissue inhibitors of metalloproteinases and vascular endothelial growth factor in canine mast cell tumours.

Degradation of the extracellular matrix and angiogenesis are associated with tumour invasion and metastasis in human and canine neoplasia. Matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs) and vascular endothelial growth factor-A (VEGF-A) are key mediators of these respective processes. Mast cell tumour (MCT) is the most common malignant cutaneous tumour in dogs. MCTs are always considered potentially malignant, but their true metastatic potential is unknown. In the present study, samples from seven grade 1, 22 grade 2 and six grade 3 MCTs were subjected to quantitative real-time polymerase chain reaction and immunohistochemistry (IHC) to evaluate MMP-2, MMP-9, membrane-type 1 MMP (MT1-MMP), TIMP-2 and VEGF-A mRNA and protein expression. Gelatin zymography (GZ) was also performed to evaluate MMP-2 and MMP-9 activity. MMP-9 and VEGF-A mRNA increased with histological grade, while TIMP-2 decreased with increasing grade. Gene expression data obtained for MMP-9, VEGF-A and TIMP-2 were confirmed by IHC for evaluation of the respective proteins. In contrast, MMP-2 and MT1-MMP had variable, but similar, expression for both mRNA and protein. Despite the high variability observed, there was correlation between MMP-2 and MT1-MMP mRNA expression (r=+0.91, P<0.0001). The MMP-2:TIMP-2 and MMP-9:TIMP-1 mRNA ratios showed an imbalance between MMPs and their specific inhibitors in MCTs, which increased with the histological grade. Finally, the activities of both latent and active forms of MMP-2 and MMP-9 were evaluated by GZ and there were significant increases in their activities with increasing histological grade and immunohistochemical expression. This study demonstrates that MMP-9, TIMP-2 and VEGF-A expression is related to histological grade and suggests that these markers are possible indicators of malignancy and targets for therapeutic strategies.

Evaluation of indirect biomarkers for detecting corticosteroids used as illegal growth promoters in beef cattle.

The histological status of the thymus, blood cortisol concentration and circulating neutrophil:lymphocyte ratio were evaluated in 349 slaughtered beef cattle, to assess the potential of these parameters as indirect biomarkers of the illegal use of corticosteroids in meat production. The livers of 20 of the animals were analysed chemically for residues of corticosteroids. The morphology of the thymus was examined for adipose tissue infiltration, cortical atrophy and 'starry sky' appearance, and on the basis of these characteristics, the animals were considered to be negative, suspected or positive for illegal corticosteroid treatment. The animals considered to be negative had a mean cortisol concentration that was significantly higher (29 ng/ml) than that of the animals suspected for corticosteroid treatment (22 ng/ml). Using the chemical analysis as the gold standard for identifying illegally treated animals, the histological examination of the thymus had a sensitivity of 100 per cent and a specificity of 85 per cent. The samples that were positive by chemical analysis had cortisol concentrations of less than 2.0 ng/ml, whereas the mean cortisol concentration of the negative samples was 10.3 ng/ml.

Intra-pelvic chondrolipoma in a dog.

An 11-year-old male dog with dysuria-stranguria, progressing to anuria, had a multilobulated, firm mass in the perineal area, embedded in the fibroconnective adipose tissue of the pelvic cavity. The mass, which was resected surgically, was unencapsulated and composed of multiple islands of hyaline cartilage, interspersed with mature adipose tissue, and myxoid and fibrous tissues. Foci of chondroid metaplasia were present. Histological and immunohistochemical examination confirmed the mesenchymal origin of the tumour. A diagnosis of intra-pelvic chondrolipoma was made.

Pathologic findings of highly pathogenic avian influenza virus A/Duck/Vietnam/12/05 (H5N1) in experimentally infected pekin ducks, based on immunohistochemistry and in situ hybridization.

The ongoing H5N1 Asian epidemic is currently affecting a number of avian species including ducks. These birds are an important part of the poultry industry in the affected countries, and it is likely that they are acting as a reservoir of infection. Ten Pekin ducks were challenged with 100 microl containing 10(7) 50% egg infective dose of the highly pathogenic avian influenza virus (HPAIV) A/Duck/Vietnam/12/05 (H5N1), administered by an intra-nasal and oral route. Clinical symptoms were recorded twice a day up to 14 days postinfection (dpi). Clinical signs were first noted at 2 dpi, with conjunctivitis and slight depression, and progressed over a period of 1-3 days to severe neurologic signs consisting of torticollis, incoordination, tremors, and seizures. Survival times varied from 3 to 7 dpi. On postmortem examination, hemorrhages were observed in the duodenum, ceca, proventriculus, ventriculus, trachea, pancreas, and brain. Histologic lesions, as well as immunohistochemistry positivity, were recorded in the pancreas and brain. In situ hybridization revealed viral antigen associated with acinar pancreatic cells, bronchial epithelial cells, and with cells of the central nervous system as well as neurons of the submucosal plexus of the duodenum. Our experimental findings agree with those previously observed in ducks naturally infected with HPAIV H5N1 viruses, confirming the acquired viral neurotropism and pancreatotropism, as previously noted in other avian species, as well as in humans.