RÉSUMÉ
Papillomatous digital dermatitis (PDD) is one of the most prevalent diseases of cattle, adversely affecting the dairy industry by its negative effect on milk production and reproductive performance. Our objective was to use culture-independent methods to determine the microbial diversity in different strata of PDD lesions of three Holstein dairy cows, analyzing whether major differences exist compared to foot skin of three non-infected cows. Both group-specific 16S rRNA gene PCR-denaturing gradient gel electrophoresis and clone library sequencing of broad-range 16S rRNA gene showed differences between the microbial composition of healthy dairy cows and the different strata of the lesion. The predominant bacterial community in the lesion, regardless of the stratum, consisted of 166 specific phylotypes belonging to seven bacterial phyla. Spirochetes (particularly, treponemes) was the most prominent group detected in PDD deep biopsies and was only found in samples from the lesion. Additionally, one phylotype phylogenetically affiliated with uncultured Euryarchaeota was detected in two strata of the lesion. Sequences from healthy foot skin samples revealed 86 specific phylotypes that were affiliated with Firmicutes and Proteobacteria. Our study corroborates the theory that treponemes are involved in PDD disease etiology and suggests, for the first time, the presence of archaeal members in this particular bovine infection.
Sujet(s)
Bactéries/classification , Maladies des bovins/microbiologie , Dermatite digitée/microbiologie , Animaux , Bactéries/génétique , Bactéries/isolement et purification , Séquence nucléotidique , Biodiversité , Bovins , Femelle , Données de séquences moléculaires , État de New York , Réaction de polymérisation en chaîne , Spirochaetales/classification , Spirochaetales/génétique , Spirochaetales/isolement et purification , Infections à Spirochaetales/médecine vétérinaire , Treponema/classification , Treponema/génétique , Treponema/croissance et développementRÉSUMÉ
OBJECTIVE: To compare agreement between 2 pregnancy tests in dairy cattle. DESIGN: Evaluation study. ANIMALS: 976 and 507 cattle for phases 1 and 2, respectively. PROCEDURES: Blood samples were collected, and palpation per rectum (PPR) was performed on cattle. Blood samples for the pregnancy-specific protein B (PSPB) ELISA were sent by courier to a commercial laboratory with results returned later. Results of PPR were extracted from herd records. Statistical comparison of results was performed by use of a mixed linear model and N analysis. RESULTS: Of 571 cattle classified as pregnant by the PSPB ELISA in phase 1, 30 (5%) were nonpregnant by PPR. Mean +/- SE adjusted optical density (OD) of cattle classified pregnant by both tests was significantly higher (0.31 +/- 0.01), compared with the adjusted OD of cattle classified pregnant by the PSPB ELISA and nonpregnant by PPR (0.22 +/- 0.02). Of 255 cows classified pregnant by the PSPB ELISA in phase 2, 31 (12%) were nonpregnant by PPR. Mean +/- SE adjusted OD of cattle classified pregnant by both tests was significantly higher (0.26 +/- 0.01), compared with the adjusted OD of cattle classified pregnant by the PSPB ELISA and nonpregnant by PPR (0.21 +/- 0.01). The N value was 0.82 and 0.81 for phases 1 and 2, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Good agreement existed between the 2 tests, especially at longer intervals after insemination. Discrepant results appeared to be attributable to a nonviable fetus, embryonic loss, or fetal loss.
Sujet(s)
Bovins/physiologie , Toucher rectal/médecine vétérinaire , Test ELISA/médecine vétérinaire , Tests de grossesse/médecine vétérinaire , Glycoprotéines bêta 1 spécifiques de la grossesse/analyse , Animaux , Marqueurs biologiques/sang , Bovins/sang , Toucher rectal/méthodes , Test ELISA/méthodes , Études d'évaluation comme sujet , Femelle , Viabilité foetale/physiologie , Grossesse , Tests de grossesse/méthodes , Tests de grossesse/normes , Sensibilité et spécificitéRÉSUMÉ
Food supply veterinarians who intend to enter dairy cattle practice or other related career activities are in need of up-graded skills to better serve the dairy industry as it continues to evolve. The time available for students to increase their abilities within the conventional professional curriculum is scarce, especially as those with food-supply interests are a minority of students competing for time and resources. The dairy industry has need of skilled veterinarians who are not only well versed in their traditional capabilities, but who also have an understanding of the complete picture of that industry as a "farm-to-fork" experience. Society at large also stands to benefit from the presence of skilled dairy veterinarians contributing to the production of safe, affordable dairy foodstuffs in a manner deemed sustainable and humane. Veterinarians in practice can and do acquire the necessary skills to make themselves relevant to their clients and consumers; however, better preparation of entry-level veterinarians could increase their value to their employers, clients, themselves, and society in a more timely manner. Cornell University's College of Veterinary Medicine developed the Summer Dairy Institute to provide an avenue for advancing the skills of new veterinarians as a means to address the current and future needs of the dairy industry. This article describes the need for, concept of, and experience with that program.
Sujet(s)
Compétence clinique , Industrie laitière/enseignement et éducation , Enseignement vétérinaire , Internat spécialité paramédicale , Vétérinaires/psychologie , Médecine vétérinaire , Animaux , Bovins , Programme d'études , Femelle , Contrôle des aliments , Approvisionnement en nourriture/normes , Humains , Étudiants/psychologie , Enseignement/méthodes , Enseignement/normes , EffectifRÉSUMÉ
Cases of omasal dilation and displacement in 4 dairy cows are described. The disease was initially diagnosed by a combination of history and clinical signs that included right-sided abdominal distension, rectal palpation, and decreased milk production. The condition was confirmed by laparotomy or necropsy.
Sujet(s)
Maladies des bovins/diagnostic , Feuillet/anatomopathologie , Maladies de l'estomac/médecine vétérinaire , Animaux , Bovins , Maladies des bovins/épidémiologie , Maladies des bovins/chirurgie , Issue fatale , Femelle , Lactation/physiologie , Laparotomie/médecine vétérinaire , Maladies de l'estomac/diagnostic , Maladies de l'estomac/épidémiologie , Maladies de l'estomac/chirurgie , Résultat thérapeutiqueRÉSUMÉ
OBJECTIVE: To evaluate effect of twin birth calvings on milk production, reproductive performance, and survival of lactating cows. DESIGN: Retrospective observational cohort study. ANIMALS: 33,868 cows from 20 farms. PROCEDURES: Data on age at calving for primiparous cows and mature equivalent milk yield for multiparous cows, assistance at calving, stillbirths, twin births, gestation duration, pregnancy at the end of the data collection period, and culling-death for all cows were extracted from farm computer records and used for statistical analysis. RESULTS: Prevalence of twin parturitions was 1.3% (159/12,050) and 6.5% (1,410/21,818) for primiparous and multiparous cows, respectively. Primiparous and multiparous cows with singletons produced more milk than cows with live twins or at least 1 dead twin (primiparous, 33.1 vs 31.9 vs 31.2; multiparous, 36.5 vs 35.7 vs 35.0). Multiparous cows with dead twins produced less milk than cows with live twins. Compared with dams with singleton birth, cows with twins were 0.78 times as likely to conceive and 1.42 times as likely to die or be culled. Cows with dead twins also had increased time to conception, compared with live twins. CONCLUSIONS AND CLINICAL RELEVANCE: Twin birth was associated with decreased survival, milk production, and reproductive performance. Having at least 1 dead twin was even more detrimental than having live twins and resulted in decreased milk production and reproductive performance of lactating cows.
Sujet(s)
Bovins/physiologie , Mort foetale/médecine vétérinaire , Lactation/physiologie , Lait/métabolisme , Reproduction/physiologie , Jumeaux , Animaux , Études de cohortes , Femelle , Parité , Grossesse , Prévalence , Études rétrospectives , Analyse de survieRÉSUMÉ
In this retrospective study, the authors describe the gross and histologic changes associated with rupture of an abdominal artery aneurysm in 33 mature female Holstein cattle between January 1980 and June 2005 from 29 farms in upstate New York and northern Pennsylvania. Over this period, there was an increase in the number of cases submitted for necropsy per year, and a seasonal trend did not exist. Affected animals ranged from 2.5 to 5.5 years of age. Grossly affected cattle exhibited marked hemoabdomen. There was marked dilation and rupture of the abdominal aorta or one of its branches, including the mesenteric, left gastric, celiac artery, right ruminal artery, or left ruminal artery. Histologically, the tunica media of the affected arteries was often thin and irregular in width with disrupted, fragmented, and coiled elastin. Granulation tissue and hemorrhage was localized at the site of rupture. There was mild-to-marked hyperplasia of the tunica intima that was irregular and disorderly with adjacent smooth-muscle hyperplasia within the tunica media. In addition, in a fraction of cases, there was mild-to-moderate mucinous change (48%) and mineralization (30%) within the tunica media. To the authors' knowledge, this is the first description of the gross and histologic changes in Holstein cows with abdominal artery aneurysm and rupture.
Sujet(s)
Rupture d'anévrysme/médecine vétérinaire , Anévrysme de l'aorte abdominale/médecine vétérinaire , Maladies des bovins/anatomopathologie , Facteurs âges , Rupture d'anévrysme/anatomopathologie , Animaux , Anévrysme de l'aorte abdominale/anatomopathologie , Bovins , Femelle , Histocytochimie/médecine vétérinaire , État de New York , Pennsylvanie , Études rétrospectives , SaisonsRÉSUMÉ
Hostein cows (n=141) in five commercial dairy herds in central New York were examined for endometritis by examination of endometrial aspirates for presence of inflammatory cells, principally neutrophils, by endometrial cytology at 40-60 days postpartum. The prevalence of cytologically-diagnosed endometritis was 53%; within herds the prevalence varied from 37 to 74% (P=0.02). There was excellent agreement between two examiners (Kappa=0.864; P<0.0001). Parity did not influence prevalence of endometritis (P=0.53). Cytologically diagnosed endometritis was associated with profoundly impaired reproductive performance; Kaplan-Meier survival analysis revealed lower overall pregnancy rate (P<0.0001). Median days open was 206 for cows with endometritis and 118 for cows free of the condition. Overall, 76% of cows in this study became pregnant by 300 days postpartum; 63% of cows with endometritis and 89% of cows without endometritis were confirmed pregnant by 300 days postpartum (P<0.003). (For these two groups, 69, and 90% respectively, became pregnant during the duration of the study). Pregnancy to first service percentage was lower (11 versus 36%; P=0.001) for cows with than without endometritis, and these cows required more services before 50% became pregnant (3 versus 2; P=0.006). In a second study using 22 cows in a university-owned herd, the prevalence of cytological evidence of inflammation was 100% at 2 weeks postpartum, and dropped to 89, 58, and 41% at 4, 6, and 8 weeks, respectively. Endometritis diagnosed by endometrial cytology late in the voluntary waiting period was highly prevalent and exerted a profoundly detrimental effect on subsequent reproductive performance, making this condition potentially extremely costly to the North American dairy industry.
Sujet(s)
Maladies des bovins/épidémiologie , Endométrite/médecine vétérinaire , Reproduction , Animaux , Bovins , Cytodiagnostic , Endométrite/diagnostic , Endométrite/épidémiologie , Femelle , Infertilité féminine/étiologie , Infertilité féminine/médecine vétérinaire , Granulocytes neutrophiles , Période du postpartum , Grossesse , Facteurs tempsRÉSUMÉ
OBJECTIVE: To determine the prevalence of biofilm formation under long-term cell culture conditions in serum samples of dairy cattle, goats, cats, and dogs, and to determine whether there is an association between nanobacteria and biofilm formation. SAMPLE POPULATION: Serum samples of clinically normal animals (313 dairy cattle, 48 goats, 140 dogs, and 44 cats) and animals with various medical conditions (60 dogs and 116 cats). PROCEDURE: Serum was incubated under cell culture conditions and observed for biofilm formation by use of light microscopy, electron microscopy, and spectroscopy. A polymerase chain reaction assay was developed to identify 16S rRNA gene sequences of nanobacteria. RESULTS: Biofilm formation developed in serum samples of 304 of 313 (97%) cattle, 44 of 48 (92%) goats, 44 of 44 (100%) cats, and 126 of 140 (90%) dogs. Prevalence of serum samples with positive results for biofilm formation was not significantly different between cats or dogs with and without medical conditions associated with pathologic extraskeletal calcification processes. Scanning electron microscopy and spectroscopy of biofilm samples revealed small coccoid particles consisting mainly of calcium and phosphate. Polymerase chain reaction assay failed to amplify sequences of nanobacteria. CONCLUSIONS AND CLINICAL RELEVANCE: Under long-term cell culture conditions, biofilm made up of aggregates of calcium and phosphate crystals does form in serum samples of clinically normal dairy cattle, goats, cats, and dogs. Disease, however, does not predispose to biofilm formation in serum samples of dogs and cats. Our findings did not support the existence of nanobacteria in serum samples of cattle, goats, cats, and dogs.
Sujet(s)
Bactéries/croissance et développement , Bactéries/isolement et purification , Biofilms/croissance et développement , Capra/sang , Animaux , Bactéries/génétique , Bactéries/ultrastructure , Chats , Bovins , Techniques de culture cellulaire , Chiens , Femelle , Gènes bactériens/génétique , Mâle , Données de séquences moléculaires , Réaction de polymérisation en chaîne , ARN ribosomique 16S/génétique , Spectrophotométrie UVRÉSUMÉ
We evaluated serum examination as an alternative to fecal analysis for the diagnosis of exposure to Cryptosporidium parvum in cattle. The accuracy of the serum ELISA was compared to the combined results of concentration flotation microscopy and fecal enzyme immunoassay. The expected performance of the serum ELISA at different levels of infection with C. parvum was evaluated using the predicative values positive and negative. Optimal conditions for the serum ELISA can be achieved by diluting the serum samples 1:20 and the conjugate 1:8,000. The serum ELISA had a relatively high sensitivity of 97.5% (95% CI=87-100%) and poor specificity, 4% (95% CI=1-20%). There was a poor agreement between the serum ELISA and the fecal tests (kappa=0) on samples collected from adult cows in a high-risk and a low-risk population. Examination of some of these fecal samples using a PCR detection method demonstrated the presence of C. parvum DNA in 10% of the samples.
Sujet(s)
Anticorps antiprotozoaires/sang , Maladies des bovins/diagnostic , Cryptosporidiose/médecine vétérinaire , Cryptosporidium parvum/isolement et purification , Test ELISA/méthodes , Fèces/parasitologie , Animaux , Bovins , Maladies des bovins/immunologie , Maladies des bovins/parasitologie , Cryptosporidiose/diagnostic , Cryptosporidiose/immunologie , Cryptosporidium parvum/pathogénicité , Fèces/cytologie , Humains , Numération des oeufs de parasites/médecine vétérinaire , Valeur prédictive des tests , Facteurs de risque , Sensibilité et spécificité , Tests sérologiques , Sol/analyse , Sol/parasitologieRÉSUMÉ
OBJECTIVE: To determine prevalence of udder cleft dermatitis in a dairy herd that was experiencing an outbreak of sarcoptic mange. DESIGN: Clinical survey. ANIMALS: 1,597 Holstein cows and late-gestation heifers. PROCEDURE: Animals were examined for udder cleft dermatitis and for skin lesions consistent with sarcoptic or chorioptic mange. Skin scrapings were collected from 56 cows and examined for ectoparasites. The herd was revisited 1 year later, and prevalences of udder cleft dermatitis and lesions consistent with mange were determined in 506 cows. RESULTS: Of the 1,597 cattle examined, 280 (18%) had udder cleft dermatitis, and 1,397 (87.5%) had lesions consistent with mange. In 43 of 56 (77%) cows, skin scrapings revealed Sarcoptes mites. Udder cleft dermatitis was significantly more common in older than in younger cows. In first-lactation cows, udder cleft dermatitis was less common during the first 4 months of lactation than in the later stages of lactation, but udder cleft dermatitis was identified in cows in all stages of lactation and in cows that were not lactating. The herd was treated with eprinomectin to control mites, and prevalence of lesions consistent with mange 1 year later was only 2.8%. However, prevalence of udder cleft dermatitis was still 12%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cows in any stage of lactation and cows that are not lactating can have udder cleft dermatitis but that lesions are more common in older cows. Control of sarcoptic mange was accompanied by a moderate reduction in the prevalence of udder cleft dermatitis but did not eliminate the condition.