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1.
Vet Parasitol ; 320: 109962, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37276628

ABSTRACT

The objectives of the present study were: (a) to describe the prevalence of helminth infections from pooled faecal samples from goat herds across Greece, (b) to evaluate herd-related factors potentially associated with the presence of these infections in the herds and (c) to compare the findings to those of a previous relevant study performed in sheep flocks. A cross-sectional study was carried out in 119 goat herds around Greece. Helminths were recovered from samples from 93.3% of herds: Dicrocoelium dendriticum (from 15.1% of herds), Paramphistomum cervi (from 0.8% of herds), Moniezia spp. (from 25.2% of herds), Trichostrongylidae (from 89.1% of herds), Nematodirus spp. (from 16.8% of herds), Strongyloides papillosus (from 5.0% of herds), Trichuris spp. (from 18.5% of herds) and lungworms (from 23.5% of herds). Mean epg counts in all herds in the study were 219 epg. In multivariable analyses, for 'high (> 300) epg counts in faecal samples' the age of kid removal from their dams (p = 0.045) was found to be a significant factor, for 'high proportion (> 64%) of Teladorsagia spp. in faecal samples' the month of the start of the kidding season (p = 0.045) was a significant factor, for 'high proportion (> 27%) of Haemonchus contortus in faecal samples' nutritional modifications during gestation (p = 0.002) and application of reproductive control practices in the farm (p = 0.013) were the significant factors and for 'presence of D. dendriticum in faecal samples' the number of veterinary visits to the farm annually (p = 0.040) was found to be significant.


Subject(s)
Goat Diseases , Helminthiasis , Helminths , Sheep Diseases , Animals , Sheep , Greece/epidemiology , Cross-Sectional Studies , Feces/parasitology , Goats , Parasite Egg Count/veterinary , Goat Diseases/epidemiology , Goat Diseases/parasitology , Sheep Diseases/epidemiology , Sheep Diseases/parasitology
2.
Anim Reprod Sci ; 218: 106460, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32507269

ABSTRACT

Objectives were to evaluate characteristics of uterine involution in ewes with pregnancy toxaemia during gestation and to study effects on subsequent reproductive performance. Pregnancy toxaemia was induced in ewes (A) by feeding an energy-deficient diet as confirmed by detecting ß-hydroxybutyrate concentrations in blood indicative of this disorder. There was also a control group (C). Animals were evaluated until the 60th day post-partum using clinical and ultrasonographic examinations. Vaginal swab samples and uterine biopsy tissue samples were collected for bacteriological and cytological examination; biopsy samples were prepared for histological examination. Ewes were subsequently placed with rams and reproductive performance was ascertained. Post-partum, during the ultrasonographic examination of the uterus, ewes of Group A had caruncle and uterine lumen diameters, as well as a uterine thickness greater than ewes of Group C. Post-partum uterine blood flow volume was greater in ewes of the A than C group. Neutrophils predominated in vaginal samples, with the neutrophil proportion being less in ewes of Group A than C. There were no differences in the uterine involution process between groups. During the subsequent reproductive season, all the ewes of Group A lambed normally and produced viable lambs. It is concluded that there were no adverse effects on subsequent reproductive performance of ewes previously affected with pregnancy toxaemia, when appropriate health management was performed.


Subject(s)
Pre-Eclampsia/veterinary , Sheep Diseases/pathology , Uterus/pathology , Animals , Epithelial Cells , Epithelium/pathology , Female , Pregnancy , Sheep , Sheep Diseases/diagnostic imaging , Sheep Diseases/microbiology , Ultrasonography, Doppler , Uterus/diagnostic imaging , Uterus/microbiology , Vagina/cytology
3.
Vet Microbiol ; 239: 108480, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31767091

ABSTRACT

Although coagulase-negative staphylococci are the primary aetiological agents of subclinical mastitis in ewes, there is little information regarding vaccination against that infection. The objective of this study was to evaluate the efficacy of a vaccine against staphylococcal mastitis in ewes under experimental conditions. The antigen in the vaccine is based on a bacterin of Staphylococcus aureus strain, expressing the exopolysaccharide poly-N-acetylglucosamine (PNAG), which is involved in biofilm formation by these bacteria. Ewes in groups A (n = 17) or B (n = 6) were given an initial vaccination 5 weeks before expected lambing, followed by a repeat administration 21 days later. Ewes in groups C (n = 8) or D (n = 6) were unvaccinated controls. Ewes in group A (n = 17) or C (n = 8) were challenged with a biofilm-forming S. chromogenes; animals in subgroups A1 or C1 were challenged on the 10th and those in A2 or C2 on the 50th day after lambing. Ewes in groups B or D were uninoculated controls. Clinical examinations of ewes, ultrasonographic examinations of udder, milk yield measurements, blood sampling for detection of anti-PNAG specific antibodies and milk sample collection for bacteriological and cytological examinations were performed up to 52nd day post-challenge. Finally, biopsies were performed for mammary tissue collection for histopathological examination. Among group A ewes, 29% developed systemic signs and 59% signs in the inoculated gland; the respective figures for group C were 50% and 100% (P =  0.040 for mammary signs). The median total clinical score was 2.0 for A and 5.5 for C ewes (P =  0.025). For A, but not for C, clinical scores decreased progressively during the study (P =  0.018 and P =  0.47, respectively). The duration of mastitis was shorter in A (4 days) than in C (17.5 days) ewes (P =  0.022). Bacterial counts were lower in milk samples from A than from C ewes, for samples collected from the inoculated and the uninoculated (P <  0.01) mammary glands of these ewes. Somatic cell counts in samples from inoculated and uninoculated mammary glands of A ewes were higher than in samples of C ewes (P <  0.02). There were differences for gray-scale evaluations during ultrasonographic examination and for milk yield measurements between groups (P <  0.01). Median bacterial counts in tissue samples from A ewes (0 cfu g-1) were lower than in ones from C (6.5 cfu g-1) ewes (P =  0.041). The median score for histopathological findings in tissue samples from inoculated glands of A was lower than that for C ewes: 1 versus 2 (P =  0.014). It is concluded that mastitis was less severe in vaccinated animals, as indicated by a wide array of measures.


Subject(s)
Bacterial Vaccines/standards , Biofilms , Mastitis/veterinary , Sheep Diseases/prevention & control , Animals , Female , Mammary Glands, Animal/microbiology , Mastitis/microbiology , Mastitis/pathology , Mastitis/prevention & control , Milk/cytology , Milk/microbiology , Sheep , Sheep Diseases/microbiology
4.
J Dairy Sci ; 102(10): 9328-9344, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31400892

ABSTRACT

Our objective was to evaluate the efficacy of a vaccine against staphylococcal mastitis in 5 dairy sheep farms, with 316 ewes in the vaccinated (V) group and 307 in the control (C) group studied throughout a lactation period. Two administrations of the vaccine were performed during the last stage of gestation of ewes. Starting 15 d after lambing and at monthly intervals thereafter, up to 9 milk samplings were performed for bacteriological and cytological examinations. Staphylococcal isolates recovered were examined for biofilm formation. Blood samples were collected for measurement of IgG poly-N-acetylglucosamine-specific antibodies. The most frequently isolated bacteria were staphylococci: 56.4 and 76.1%, respectively, of total isolates recovered from ewes of group V and C, respectively; staphylococci as causal agents of mastitis were isolated less frequently from V (5.3%) than in ewes in C (10.3%). Among mastitis-associated staphylococcal isolates recovered from V ewes, a smaller proportion was biofilm-forming than among ones from C: 53.2% versus 74.9% of isolates; biofilm-forming staphylococci as causal agents of mastitis were isolated less frequently from ewes in group V (2.3%) than in ewes in group C (6.0%). Anti-poly-N-acetylglucosamine-specific antibody values increased in V ewes and were higher than in C; a greater proportion of ewes with low antibody titers developed staphylococcal mastitis (41.4%) than of V ewes with high antibody titers (17.0%). Incidence risk of mastitis, staphylococcal mastitis, and biofilm-associated staphylococcal mastitis was smaller in V than in C: 36.7, 17.1, and 8.0% versus 44.3, 30.9, and 18.9%, respectively. The first case of staphylococcal mastitis occurred later in V than in C: third versus second sampling point. Overall, efficacy of the vaccine was 44.6% for staphylococcal mastitis, 57.7% for biofilm-associated staphylococcal mastitis, 33.1% for staphylococcal intramammary infection, and 51.5% for biofilm-associated staphylococcal intramammary infection. Nevertheless, vaccination should not be the only means for controlling mastitis; other udder health management measures should be included therein to improve control of the infection.


Subject(s)
Bacterial Vaccines/administration & dosage , Biofilms , Mastitis/veterinary , Sheep Diseases/prevention & control , Staphylococcal Infections/veterinary , Animals , Female , Incidence , Lactation , Mammary Glands, Animal/microbiology , Mastitis/prevention & control , Milk/microbiology , Random Allocation , Sheep , Sheep Diseases/microbiology , Staphylococcal Infections/prevention & control
5.
N Z Vet J ; 67(5): 234-240, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31079570

ABSTRACT

AIMS: To compare stainless steel staples and polypropylene suture material for primary closure of wounds after teat amputation in ewes and to assess progress of healing in the presence or absence of intramammary infection (IMI). METHODS: Chios-cross ewes, aged 3-5 years were randomly allocated to be infected in one teat with 1,200-1,500 cfu of Mannheimia haemolytica 5 days after parturition (groups A and B; n = 8 in each group) or remain uninfected (groups C and D; n = 4 in each group). On the following 4 days one teat from each ewe was amputated 2.5 cm from the teat end and the wound was closed using skin staples (groups A and C) or polypropylene sutures (groups B and D). Clinical evaluation of wound healing was performed between 1-21 days after surgery. On day 21 tissue sections were collected for tensiometric and histological evaluation. RESULTS: The mean interval from the start to finish of wound closure was shorter when staples were used than when sutures were used (p < 0.001). Healing scores were lower (improved) for ewes in group A than B between days 1-7 after surgery (p = 0.005), but were similar between days 10-21 (p = 0.43). Healing scores were similar in groups C and D (p = 0.98). The tensile strain at maximum load was higher in tissue from group A than B (p = 0.001) and D (p = 0.004), but all other tensiometric measures were similar between groups. Histologically, collagen density was higher in sections from group A than B (p = 0.05) and D (p = 0.01), and angiogenesis was lower in sections from group A than B (p = 0.03) and D (p = 0.01). CONCLUSIONS AND CLINICAL RELEVANCE: Skin staples and polypropylene sutures can be used effectively for primary closure of teat wounds, even in the presence of IMI. Skin staples had the advantage of a reduction in surgical time. ABBREVIATION: IMI: intramammary infection.


Subject(s)
Mammary Glands, Animal/surgery , Sheep Diseases/surgery , Suture Techniques/veterinary , Wound Healing , Animals , Disease Models, Animal , Female , Greece , Mammary Glands, Animal/microbiology , Mammary Glands, Animal/pathology , Mannheimia , Mastectomy/veterinary , Pasteurellaceae Infections/veterinary , Polypropylenes , Random Allocation , Sheep , Sheep Diseases/microbiology , Surgical Stapling/veterinary , Sutures , Treatment Outcome
6.
Article in English | MEDLINE | ID: mdl-30711044

ABSTRACT

Objectives of the work presented herewith were to investigate association of prevalence of subclinical mastitis with environmental (climatic and topographic) factors and to identify factors potentially predisposing ewes to the disease. Milk samples were collected from 2198 sheep in 111 farms, in all 13 administrative regions of Greece, for bacteriological and cytological examination. Data on farm location were collected in the field using hand-held Global Positioning System Garmin units. The geo-references were resolved to specific farm level. Prevalence of subclinical mastitis was 0.260. Main aetiological agents were staphylococci (Staphylococcus aureus and coagulase-negative species), which accounted for 0.699 of all isolates recovered. In a multivariable mixed-effects analysis, the two environmental variables found to be associated with increased prevalence of subclinical mastitis were the minimum temperature of coldest month (coefficient: -0.084 ± 0.033, P = 0.014) and the mean temperature for 30 days prior to sampling date (coefficient: 0.031±0.014, P = 0.029).


Subject(s)
Disease Susceptibility , Environment , Mastitis/veterinary , Sheep Diseases/epidemiology , Sheep Diseases/etiology , Animals , Farms , Female , Geography , Greece/epidemiology , Prevalence , Sheep
7.
Vet Parasitol ; 265: 56-62, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30638521

ABSTRACT

The objective of the present study was to study, under field conditions, potential associations between gastrointestinal nematode parasitism and subclinical mastitis in ewes during the lactation period. Faecal and milk samples were collected from 240 ewes in 16 farms, for parasitological and bacteriological plus cytological examination, respectively. In the population sampled, prevalence of gastrointestinal nematode infection was 63.0%; mean faecal count was 357.7 ± 32.4 eggs per gram (epg); Teladorsagia spp. larvae were identified more frequently in coprocultures (median proportion among farms: 53.0%). The prevalence of subclinical mastitis was 22.6%; coagulase-negative Staphylococcus spp. were identified more frequently as causal agents (64.7% of isolates recovered from cases of the disease). There was clear evidence that the prevalence of subclinical mastitis was higher among ewes with gastrointestinal nematode infection than among ewes without: 26.4% and 16.1% (P = 0.047), respectively. Further, the prevalence of subclinical mastitis was higher in ewes with high faecal epg: 31.1% versus 18.6% in ewes with low faecal epg (P = 0.027). Mean epg counts in ewes with mastitis were significantly higher: 500 ± 84 (mean ± standard error of the mean), than epg counts in healthy ewes: 316 ± 36 (P = 0.024). The findings further underline the importance of concurrent parasitic and bacterial infections. Moreover, results also suggest further factors that can play a role in development of mastitis in ewes.


Subject(s)
Gastrointestinal Diseases/veterinary , Mastitis/veterinary , Nematode Infections/veterinary , Sheep Diseases/parasitology , Animals , Female , Gastrointestinal Diseases/parasitology , Mastitis/etiology , Nematode Infections/complications , Prevalence , Risk Factors , Sheep
8.
Vet Microbiol ; 228: 119-128, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30593356

ABSTRACT

Objective was to recognise areas potentially of high risk for increased frequency of subclinical mastitis in ewes. Milk samples were collected, for bacteriological and cytological examination, from 2198 clinically healthy ewes in 111 farms in all administrative regions of Greece. Data on farms were located in the field using hand-held Global Positioning System Garmin units. Collected data were analysed by an Ecological Niche Model under the framework of a geographic information system. Two separate analyses were performed: one for subclinical mastitis independently of causal agent (prevalence in population sampled: 0.260) and one for subclinical mastitis caused specifically by slime-producing staphylococci (prevalence in population sampled: 0.153). A model was constructed in which sheep farms were divided into two clusters, according to prevalence of subclinical mastitis: farms in the upper three quartiles of prevalence were used as occurrence points for the Ecological niche modelling procedure ('infected farms'); farms in the lower quartile of prevalence within each category were (pseudo)negative points. Significant differences in environmental parametres prevailing in locations of farms into the study, were identified for up to 13 parametres between locations of farms according to management system applied in farms. When farms in each management system were considered separately, differences became evident between farms in each management system, as well as between the two infections. The factor with the highest relative contribution in the analyses was the distance from other sheep farms; other factors also of importance in the predictive models were the altitude, the maximum temperature of warmest month and the total precipitation of driest month. Verification of the model revealed that ≥ 0.760 of infected farms' were located in areas predicted as high risk for prevalence of subclinical mastitis or slime staphylococcal subclinical mastitis. The paper describes for the first time potential association of mastitis with environmental factors and presents predictive models for mastitis in ewes taking into account environmental parametres.


Subject(s)
Mastitis/veterinary , Sheep Diseases/epidemiology , Staphylococcal Infections/veterinary , Staphylococcus/isolation & purification , Animals , Ecosystem , Farms , Female , Geographic Information Systems , Greece/epidemiology , Mastitis/epidemiology , Mastitis/microbiology , Prevalence , Sheep , Sheep Diseases/microbiology , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology
9.
Vet Microbiol ; 224: 93-99, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30269797

ABSTRACT

Hitherto, research work in slime production from staphylococcal strains of mastitis origin has focused in laboratory properties of these organisms. Objective of present work was to study subclinical mastitis in sheep, caused specifically by slime-producing staphylococci: to investigate its frequency and to identify potential factors playing a role therein. Slime production was evaluated in 708 staphylococcal isolates recovered from cases of subclinical mastitis in a field study in 2198 ewes performed in an extensive countrywide field investigation across Greece. Isolates were studied by means of microbiological and molecular methods. Of these strains, 262 were characterised as slime-producing, 227 as weak slime-producing and 219 as non slime-producing. Most frequently detected genes were eno and icaB; Staphylococcus aureus possessed more genes than coagulase-negative strains; greater number of genes was detected in slime-producing than in weak slime-producing or non-slime-producing strains. Subclinical mastitis caused specifically by slime-producing staphylococci was detected in 337 ewes: prevalence in population sampled was 0.153. A multivariable mixed-effects model revealed that milking mode (highest prevalence in hand-milked flocks) and flock management system (highest prevalence in semi-intensive flocks) were the two factors associated with increased prevalence of mastitis in flocks. The results confirmed the significance of slime producing staphylococcal strains of importance in the aetiology of subclinical mastitis of sheep. Hand-milking was identified as the most important factor predisposing to that infection.


Subject(s)
Asymptomatic Infections/epidemiology , Mastitis/veterinary , Milk/microbiology , Sheep Diseases/epidemiology , Staphylococcal Infections/veterinary , Staphylococcus/physiology , Animals , Bacterial Proteins/genetics , Biofilms/growth & development , Female , Greece/epidemiology , Mastitis/epidemiology , Mastitis/microbiology , Prevalence , Risk Factors , Sheep/microbiology , Sheep Diseases/microbiology , Sheep Diseases/prevention & control , Sheep Diseases/transmission , Staphylococcal Infections/epidemiology , Staphylococcal Infections/virology , Staphylococcus/isolation & purification
10.
J Dairy Sci ; 101(8): 7297-7310, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29859691

ABSTRACT

The objectives of this work were (1) to investigate prevalence of subclinical mastitis, (2) to identify etiological agents involved, and (3) to study factors potentially predisposing ewes to subclinical mastitis. Milk samples were collected from 2,198 ewes in 111 farms with a total population of 35,925 ewes, in all 13 administrative regions of Greece, for bacteriological and cytological examination. Prevalence of subclinical mastitis was 0.260. Main etiological agents were staphylococci (Staphylococcus aureus and coagulase-negative species), which accounted for 0.699 of all isolates recovered; prevalence of staphylococcal mastitis was 0.191. In a multivariable mixed-effects analysis, the primary factor found to be associated with increased prevalence of subclinical mastitis was the management system practiced in flocks (flocks under a semi-intensive system had the highest prevalence). Other factors that were included in the multivariable model were the stage of lactation period (ewes in the 2nd month postpartum showed the highest prevalence) and application of postmilking teat dipping. In contrast, measures taken at the end of a lactation period (e.g., intramammary administration of antimicrobial agents) were not found to have an effect on prevalence of subclinical mastitis. The results confirmed the significance of subclinical mastitis as a frequent problem of ewes, with staphylococci as the primary etiological agent. The findings confirm the multifactorial nature of subclinical mastitis and indicate that its control should rely on many approaches.


Subject(s)
Mastitis/veterinary , Milk/microbiology , Sheep Diseases/diagnosis , Staphylococcal Infections/veterinary , Animals , Female , Greece/epidemiology , Mastitis/diagnosis , Mastitis/epidemiology , Sheep , Sheep Diseases/epidemiology , Staphylococcal Infections/diagnosis , Staphylococcal Infections/epidemiology , Staphylococcus
11.
Mol Genet Genomics ; 293(3): 753-768, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29372305

ABSTRACT

In the present study, genome-wide genotyping was applied to characterize the genetic diversity and population structure of three autochthonous Greek breeds: Boutsko, Karagouniko and Chios. Dairy sheep are among the most significant livestock species in Greece numbering approximately 9 million animals which are characterized by large phenotypic variation and reared under various farming systems. A total of 96 animals were genotyped with the Illumina's OvineSNP50K microarray beadchip, to study the population structure of the breeds and develop a specialized panel of single-nucleotide polymorphisms (SNPs), which could distinguish one breed from the others. Quality control on the dataset resulted in 46,125 SNPs, which were used to evaluate the genetic structure of the breeds. Population structure was assessed through principal component analysis (PCA) and admixture analysis, whereas inbreeding was estimated based on runs of homozygosity (ROHs) coefficients, genomic relationship matrix inbreeding coefficients (FGRM) and patterns of linkage disequilibrium (LD). Associations between SNPs and breeds were analyzed with different inheritance models, to identify SNPs that distinguish among the breeds. Results showed high levels of genetic heterogeneity in the three breeds. Genetic distances among breeds were modest, despite their different ancestries. Chios and Karagouniko breeds were more genetically related to each other compared to Boutsko. Analysis revealed 3802 candidate SNPs that can be used to identify two-breed crosses and purebred animals. The present study provides, for the first time, data on the genetic background of three Greek indigenous dairy sheep breeds as well as a specialized marker panel that can be applied for traceability purposes as well as targeted genetic improvement schemes and conservation programs.


Subject(s)
Genome-Wide Association Study/methods , Oligonucleotide Array Sequence Analysis/methods , Polymorphism, Single Nucleotide , Sheep/genetics , Animals , Genetic Variation , Genetics, Population , Genome-Wide Association Study/veterinary , Greece , Inbreeding , Linkage Disequilibrium , Oligonucleotide Array Sequence Analysis/veterinary , Phylogeny , Sheep/classification
12.
Vet Parasitol ; 245: 71-77, 2017 Oct 15.
Article in English | MEDLINE | ID: mdl-28969841

ABSTRACT

Objective was to study, in an experimental model, the possible role of gastrointestinal nematode infection in predisposing ewes to mastitis during the lactation period. Twenty-four ewes (A or B [n=12]), free from nematode and trematode helminths, were used. Group A animals received 5000 third-stage larvae of a trichostrongylid helminth cocktail and group B ewes were unparasitised controls. Animals in group A developed gastrointestinal trichostrongylosis confirmed by >500epg in faecal samples; mean epg of group B ewes were <20 (P<0.001). Ewes were challenged by deposition of Mannheimia haemolytica into the teat duct. In group A, 7 ewes developed clinical and 5 subclinical mastitis; no ewe in group B developed clinical mastitis, but only subclinical (12 ewes) (P=0.002). M. haemolytica was isolated from 132/132 and 121/132 udder samples from group A or B, respectively (P<0.015); increased leucocyte numbers were recorded in 66/66 and 61/66 samples, respectively (P=0.023). During post-mortem examination, mean number of helminths in gastrointestinal content was 2523 and 7.5 in group A or B, respectively (P<0.001); within group A, proportions of Teladorsagia and Haemonchus were significantly greater in ewes that developed clinical mastitis than in others which did not (0.709 and 0.162 versus 0.662 and 0.136, respectively; P<0.035). M. haemolytica was isolated from 36/36 and 19/36 udder tissue samples from group A or B, respectively (P<0.001). In ewes with subclinical mastitis (in group A or B), inducible-lymphoid-follicles were observed in the teat, which were not observed in ewes with clinical disease. Total pathology scores summed over all days were 127 and 73 for group A or B ewes, respectively (maximum possible 192; P<0.05). In general, there was positive correlation between intestinal helminth counts and pathology score (P<0.001) and between Teladorsagia counts and pathology score (P=0.002) in ewes that developed clinical mastitis. It is concluded that, in view of bacterial challenge, gastrointestinal trichostrongylosis and particularly Teladorsagia infection, might lead to clinical mastitis, through various pathogenetic pathways.


Subject(s)
Gastrointestinal Diseases/veterinary , Mastitis/veterinary , Sheep Diseases/parasitology , Trichostrongylosis/veterinary , Animals , Female , Gastrointestinal Diseases/complications , Gastrointestinal Diseases/parasitology , Mastitis/immunology , Mastitis/microbiology , Pregnancy , Sheep , Sheep Diseases/immunology , Sheep Diseases/microbiology , Trichostrongylosis/complications
13.
Epidemiol Infect ; 144(14): 3068-3079, 2016 10.
Article in English | MEDLINE | ID: mdl-27435434

ABSTRACT

The objectives of this work were (i) geographical analysis of the 2012-2014 outbreak of rabies in Greece using GIS and (ii) comparative analysis of animal cases with data of potential human exposure to rabies together with environmental data, in order to provide information for risk assessment, effective monitoring and control. Most animal cases (40/48) involved red foxes, while domestic animals were also diagnosed with rabies. Overall, 80% of the cases were diagnosed in central northern Greece; 75% of the cases were diagnosed in low altitudes (<343·5 m), within a distance of 1 km from human settlements. Median distance from livestock farms was 201·25 m. Most people potentially exposed to rabies (889/1060) presented with dog bite injuries. Maximum entropy analysis revealed that distance from farms contributed the highest percentage in defining environmental niche profiles for rabid foxes. Oral vaccination programmes were implemented in 24 administrative units of the country during 2013 and 2014, covering a total surface area of ~60 000 km2. Rabies re-occurrence in Greece emphasizes the need for ongoing surveillance in cross-border areas and in areas with intense human activity.


Subject(s)
Cat Diseases/epidemiology , Cattle Diseases/epidemiology , Disease Outbreaks , Dog Diseases/epidemiology , Foxes , Rabies/veterinary , Animals , Cat Diseases/virology , Cats , Cattle , Cattle Diseases/virology , Dog Diseases/virology , Dogs , Geographic Information Systems , Greece/epidemiology , Humans , Rabies/epidemiology , Rabies Vaccines/administration & dosage , Risk Assessment , Vaccination/veterinary
14.
Theriogenology ; 86(6): 1615-1621, 2016 Oct 01.
Article in English | MEDLINE | ID: mdl-27329156

ABSTRACT

Ghrelin, a known growth hormone (GH) secretagogue, alters gonadotropin secretion in many species. Our objectives were to study the effects of ghrelin, on GH, LH, FSH secretion, and on luteal function of the ensuing estrous cycle in cattle. The estrous cycles of eight heifers were synchronized with progesteron releasing intravaginal device, and ovulation was induced with GnRH. Eight animals were treated with 1.5 µg kg(-1) bovine ghrelin (group Ghr, n = 4) or saline (group C, n = 4). Starting with the first ghrelin injection, 13 blood samples were collected over a 4-hour period for the determination of ghrelin, GH, LH, and FSH concentration. Progesterone levels were measured in samples collected every other day after estrus expression. Data were analyzed by repeated measures of ANOVA followed by Bonferroni post hoc testing and t test. In group Ghr, ghrelin concentration increased significantly 15 minutes after the first injection and remained in elevated levels until the 90th minute after the last injection. At the time of third ghrelin injection, GH was significantly higher in the Ghr group compared with C (17.1 ± 1.3 vs. 2.6 ± 0.3 ng mL(-1), P < 0.0001). Similar differences were found for the next three samples collected 15, 30, and 60 minutes later; no difference was evident after 90 minutes. In group Ghr, the area under the curve for LH and FSH were significantly reduced compared with the ones of group C (266 ± 10.3 vs. 331.9 ± 7.3, P = 0.007 and 102.3 ± 2.0 vs. 134.9 ± 5.5, P < 0.005 for LH and FSH respectively). At particular time points the concentration of the two gonadotrophins in group Ghr was significantly lower than those of group C (15, 30, 45, 75, and 90 and 60, 75, 90, 120, and 150 minutes after GnRH administration for LH and FSH respectively). The duration of the following estrous cycle was shorter (P = 0.004) in group Ghr (19.0 ± 0.4 days) compared with C (21.8 ± 0.5 days). In days 4, 6, 8, 10, and 14, progesterone concentration was lower (P < 0.05) in group Ghr compared with C; similarly the progesterone area under the curve for group Ghr (113.1 ± 4.8) was suppressed (P = 0.007) compared with that of C (141 ± 4.8). These results imply that ghrelin acts on pituitary causing impaired response to the GnRH stimulus, and it is likely to affect luteinization of the cellular compartment of the preovulatory follicle, and/or to suppress steroidogenetic activity of the luteal cells.


Subject(s)
Cattle/physiology , Follicle Stimulating Hormone/blood , Ghrelin/pharmacology , Gonadotropin-Releasing Hormone/pharmacology , Growth Hormone/blood , Luteinizing Hormone/blood , Animals , Estrous Cycle/drug effects , Estrus , Female , Ghrelin/blood , Ovulation , Pituitary Gland/drug effects , Pituitary Gland/physiology , Progesterone/blood
15.
Pol J Vet Sci ; 19(4): 893-906, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-28092597

ABSTRACT

Small ruminants represent an important economic source in small farm systems and agriculture. Feed is the main component of livestock farming, which has gained special attention to improve animal performance. Many studies have been done to improve feed utilisation through addition of feed additives. For a long period, antibiotics have been widely used as growth promoters in livestock diets. Due to their ban in many countries, search for alternative feed additives has been intensified. Probiotics are one of these alternatives recognised to be safe to the animals. Use of probiotics in small ruminant nutrition has been confirmed to improve animal health, productivity and immunity. Probiotics improved growth performance through enhancing of rumen microbial ecosystem, nutrient digestibility and feed conversion rate. Moreover, probiotics have been reported to stabilise rumen pH, increase volatile fatty acids production and to stimulate lactic acid utilising protozoa, resulting in a highly efficient rumen function. Furthermore, use of probiotics has been found to increase milk production and can reduce incidence of neonatal diarrhea and mortality. However, actual mechanisms through which probiotics exert these functions are not known. Since research on application of probiotics in small ruminants is scarce, the present review attempts to discuss the potential roles of this class of feed additives on productive performance and health status of these animals.


Subject(s)
Animal Nutritional Physiological Phenomena , Goats , Probiotics , Sheep , Animal Feed , Animals
16.
Small Rumin Res ; 141: 5-10, 2016 Aug.
Article in English | MEDLINE | ID: mdl-32288209

ABSTRACT

Objectives of the present work were (i) to confirm pathogens implicated in cases of diarrhoea in newborn and young lambs in sheep farms in Greece and (ii) to investigate a possible relation in dissemination of pathogens between lambs and dogs present in the farm. Work was carried out in 22 sheep farms, with (i) flock size over 150 animals, (ii) presence of clinical signs of diarrhoea in lambs in the flock and (iii) close and continuous contact and movement of shepherd dogs within the animal shed of each farm. Faecal sample collection from lambs was performed within 48 h of onset of clinical signs and prior to administration of any antimicrobial or antiparasitic medication to lambs. Faecal samples were also collected from puppies in the farm. In total, samples were collected from 126 lambs and 58 puppies. Samples were processed by using established techniques for isolation of bacteria, detection of viruses and observation of protozoan oocycts. Escherichia coli isolates obtained during the study, were tested for antimicrobial resistance against a variety of antimicrobial agents. In total, 236 bacterial isolates were recovered from faecal samples of lambs and 165 isolates from faecal samples of puppies. E. coli was the most frequently isolated microorganism: 104 isolates from lambs and 109 isolates from puppies were recovered. Other bacteria isolated were Enterobacter spp., Proteus spp., Klebsiella spp., (lambs and puppies), Clostridium perfringens, Citrobacter freundi, Salmonella enterica subsp. diarizonae (only lambs) and Streptococcus spp. (only puppies). Group A Rotavirus was detected in samples from lambs (2.5%) and Parvovirus in samples from puppies (5%). Cryptosporidium spp. oocysts were observed in samples from lambs and puppies. This is the first report of isolation of S. enterica subsp. diarizonae and of detection of Rotavirus from lambs in Greece. Rates of E. coli isolates from puppies resistant to antimicrobial agents were, in general, smaller than respective rates in isolates from lambs. Two pairs of isolates from the same farm (one from a lamb and one from a puppy) with identical patterns of resistance to antimicrobial agents were detected, which provides some evidence in support of a hypothesis that members of each pair might possibly have been spread from one animal species to the other.

17.
Small Rumin Res ; 142: 61-68, 2016 Sep.
Article in English | MEDLINE | ID: mdl-32288210

ABSTRACT

Objective of this paper was to review relevant work and to present a general account of the bluetongue outbreak, which occurred in Greece in 2014. In total, 2895 outbreaks of the disease have been reported by the veterinary authorities of Greece; sheep, goats and cattle were affected with officially reported morbidity rates of 11.0%, 2.0% and 3.5%, respectively. No vaccinations were allowed and conservative measures were implemented to attempt to limit the disease, which at the end had expanded throughout the country. In field investigations, a significantly higher bluetongue morbidity rate (27.5%) in sheep has been reported. During that work, clinical anaemia was encountered, which was characterised as macrocytic, hypochromic, regenerative and non-haemolytic. Other investigations, which are reviewed in this paper, have described an outbreak of Citrobacter freundii-associated enteritis in newborn kids, offspring of goats subclinically infected with Bluetongue virus, increased rate of early embryonic deaths, reduced conception rates, increased incidence risk of mastitis and reduced milk yield in herds of subclinically-infected cattle and detection of the virus from hunter-harvested tissue samples of roe-deer. In 2015, vaccines against the disease have been licenced; vaccinations started in May 2015. Then, in 2015, only one outbreak of the disease was confirmed, which could have been the result of a combination of reasons acting concurrently to prevent further cases.

18.
Vet Microbiol ; 181(1-2): 8-14, 2015 Dec 14.
Article in English | MEDLINE | ID: mdl-26228834

ABSTRACT

Objective of this review is to discuss the role of small ruminant diet in the defence of these animals against microbial diseases, in relation to different experimental approaches and various stressors acting on animals. The effects of various diets in immune reactions and animal defences are presented. Also, effects in relation to the species studied and the type of stressors acting on animals are discussed. Evidence is provided about the significance of the diet in enhancing immune responses of small ruminants during specific conditions, e.g., around parturition, during lactation, as well as in growing lambs or kids.


Subject(s)
Animal Nutritional Physiological Phenomena/immunology , Diet/veterinary , Pregnancy, Animal/immunology , Ruminants/immunology , Stress, Physiological/immunology , Animal Feed , Animals , Female , Goat Diseases/prevention & control , Goats/growth & development , Goats/immunology , Lactation/immunology , Parturition/immunology , Pregnancy/immunology , Sheep/growth & development , Sheep/immunology , Sheep Diseases/prevention & control
19.
Vet Microbiol ; 181(1-2): 27-33, 2015 Dec 14.
Article in English | MEDLINE | ID: mdl-26233680

ABSTRACT

Objective of the paper is to review potential applications of proteomics methodologies in the study of microbial diseases of small ruminants. Proteomics has been employed for the elucidation of pathogenesis of various diseases, i.e., in the study of determinants of microbial agents and the study of host-pathogen interactions, as well as in improved disease diagnosis by the identification of biomarkers. Extensive uses of proteomics in sheep and goat diseases have been applied primarily in mastitis, in reproductive infections, in paratuberculosis, in respiratory infections and in scrapie. Mining deeper into the various proteomes and application of new methodological strategies in clinical studies will provide information about disease processes. Improvement of diagnostic techniques, development of vaccines against diseases and establishment of tools for optimum animal production are key-areas for targeted research.


Subject(s)
Bacterial Infections/veterinary , Goat Diseases/microbiology , Proteomics , Ruminants/microbiology , Sheep Diseases/microbiology , Animals , Bacterial Infections/genetics , Bacterial Infections/microbiology , Biomarkers , Female , Goat Diseases/genetics , Goats , Host-Pathogen Interactions , Proteomics/methods , Ruminants/genetics , Sheep , Sheep Diseases/genetics
20.
Vet Microbiol ; 181(1-2): 1, 2015 Dec 14.
Article in English | MEDLINE | ID: mdl-26282246
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