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1.
J Dairy Sci ; 106(1): 653-663, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400618

RESUMO

Dairy cows are predisposed to diseases during the postpartum period. Dystocia has been associated with increased risk for disease, which is likely the result of increased tissue trauma and stress during the prolonged parturition. To attenuate the inflammatory response seen in dystocic animals and improve well-being, we assessed the effects of a glucocorticoid, dexamethasone administered within 12 h after calving. Dystocia was defined as a difficult birth resulting in a prolonged calving (≥70 min after the amniotic sac appears) and was monitored through 3 video cameras in the close-up dry-cow pen. Cows meeting the dystocia definition were randomly assigned to receive a single intramuscular injection of either dexamethasone (DEX; 0.1 mg/kg of body weight; n = 43) or saline (CON, n = 44) within 12 h following a dystocic calving. Serum haptoglobin, blood ß-hydroxybutyrate (BHB) concentrations, body temperature, and several behaviors were measured for the first 7 d postpartum. Additionally, milk production and components for the first 120 d were recorded. Using a mixed model, the fixed effects of treatment, parity, calving assistance, and time, along with 2- and 3-way interactions, were analyzed with cow as a random effect. We observed that primiparous DEX cows had greater serum haptoglobin concentrations on d 3 and d 7 postpartum compared with primiparous CON cows. There was no difference between treatment groups for blood BHB concentrations and body temperature. Behavior was altered between treatments, with DEX cows having reduced activity for the first week postpartum, as well as less restlessness and increased lying times on some of the days following calving. Treatment interacted with time for milk yield, such that DEX cows produced 2.7 kg/d less milk than CON cows for the first month following calving. The administration of dexamethasone resulted in changes in behavioral measurements, which could suggest a reduction in discomfort; however, due to the reduction in milk yield for the first month following calving, DEX administration may not be applicable for typical farm use. Additional research is needed to investigate treatments for cows experiencing dystocia without detrimental effects on milk yield.


Assuntos
Doenças dos Bovinos , Distocia , Gravidez , Feminino , Bovinos , Animais , Lactação/fisiologia , Haptoglobinas , Leite , Período Pós-Parto , Paridade , Ácido 3-Hidroxibutírico , Distocia/tratamento farmacológico , Distocia/veterinária , Dexametasona/farmacologia , Doenças dos Bovinos/tratamento farmacológico
2.
J Dairy Sci ; 105(2): 1338-1345, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34955244

RESUMO

A new undesirable genetic factor, neuropathy with splayed forelimbs (JNS), has been identified recently in the Jersey breed. Calves affected with JNS are unable to stand on splayed forelimbs that exhibit significant extensor rigidity and excessive lateral abduction at birth. Affected calves generally are alert at birth but exhibit neurologic symptoms, including spasticity of head and neck and convulsive behavior. Other symptoms reported include dislocated shoulders, congenital craniofacial anomalies, and degenerative myelopathy. Inheritance of an undesirable genetic factor was determined from a study of 16 affected calves reported by Jersey breeders across the United States. All of their pedigrees traced back on both paternal and maternal sides to a common ancestor born in 1995. Genotypes revealed that JNS is attributable to a specific haplotype on Bos taurus autosome 6. Currently 8.2% of the genotyped US Jersey population are carriers of the haplotype. Sequencing of the region of shared homozygosity revealed missense variant rs1116058914 at base 60,158,901 of the ARS-UCD1.2 reference map as the most concordant with the genetic condition and the most likely cause. The single-base G to A substitution is in the coding region of the last exon of UCHL1, which is conserved across species. Mutations in humans and gene knockouts in mice cause similar recessive symptoms and muscular degeneration. Since December 2020, carrier status has been tracked using the identified haplotype and reported for all 459,784 genotyped Jersey animals. With random mating, about 2,200 affected calves per year with losses of about $250,000 would result from the 1.3 million US Jersey cows in the national population. Selection and mating programs can reduce numbers of JNS-affected births using either the haplotype status or a direct gene test in the future. Breeders should report calf abnormalities to their breed association to help discover new defects such as JNS.


Assuntos
Membro Anterior , Padrões de Herança , Animais , Bovinos/genética , Feminino , Genótipo , Haplótipos , Camundongos , Mutação , Estados Unidos
3.
J Dairy Sci ; 105(3): 2369-2379, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35086707

RESUMO

Clinical mastitis (CM) incidence is considerable in terms of cows affected per year, but cases are much less common in terms of detections per cow per milking. From a modeling perspective, where predictions are made every time any cow is milked, low CM incidence per cow day makes training, evaluating, and applying CM prediction models a challenge. The objective of this study was to build models for predicting CM incidence using time-series sensor data and choose models that maximize net return based on a cost matrix. Data collected from 2 university dairy farms, the University of Florida and Virginia Polytechnic Institute and State University, were used to gather representative data, including 110,156 milkings and 333 CM cases. Variables used in the models were milk yield, protein, lactose, fat, electrical conductivity, days in milk, lactation number, and activity as the number of steps, lying time, lying bouts, and lying bout duration. Models that predicted either likelihood of CM caused by gram-negative (GN) or gram-positive (GP) bacteria on each day were derived using extreme gradient boosting with weighting favoring true-positive cases, logistic responses, and log-loss errors. Model accuracies were determined using data randomly held out from the training set on each run. All variables considered were in terms of change (slope) over previous days, including the day CM was visually detected. The GN models had a median sensitivity (Se) of 52.6% and specificity (Sp) of 99.8%, whereas the GP models had a median Se of 37.5% and Sp of 99.9% when tested on the held-out data. In our models optimized to reduce cost from predictions, the Se was much less than Sp, suggesting that CM models might benefit from greater model weighting placed on Sp. Results also highlight the importance of positive predictive value (true positive cases per predicted positive case) along with Sp and Se, as models built on sparse data tend to predict too many false-positive cases. The calculated partial net return of our GN and GP models were -$0.15 and -$0.10 per cow per lactation, respectively, whereas International Organization for Standardization (ISO) standard models with Se of 80% and Sp of 99% would return -$1.32 per cow per lactation. Models chosen that minimized the cost to the farmer differed markedly from models that met ISO guidelines, showing asymmetry in targets between Sp and Se when the disease incidence rate is low. Because of the unique challenges that low-incidence diseases like CM present, we recommend that future CM predictive models consider the economic and practical implications in addition to the traditional model evaluation metrics.


Assuntos
Indústria de Laticínios , Mastite Bovina , Animais , Bovinos , Indústria de Laticínios/métodos , Fazendas , Feminino , Incidência , Lactação , Mastite Bovina/microbiologia , Leite/metabolismo
4.
J Dairy Sci ; 103(3): 2602-2614, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882223

RESUMO

Opportunities exist for automated animal health monitoring and early detection of diseases such as mastitis with greater on-farm adoption of precision technologies. Our objective was to evaluate time series changes in individual milk component or behavioral variables for all clinical mastitis (CM) cases (ACM), for CM caused by gram-negative (GN) or gram-positive (GP) pathogens, or CM cases in which no pathogen was isolated (NPI). We developed algorithms using a combination of milk and activity parameters for predicting each of these infection types. Milk and activity data were collated for the 14 d preceding a CM event (n = 170) and for controls (n = 166) matched for breed, parity, and days in milk. Explanatory variables in the univariate and multiple regression models were the slope change in milk (milk yield, conductivity, somatic cell count, lactose percentage, protein percentage, and fat percentage) and activity parameters (steps, lying time, lying bout duration, and number of lying bouts) over 7 d. Slopes were estimated using linear regression between d -7 and -5, d -7 and -4, d -7 and -3, d -7 and -2, and d -7 and -1 relative to CM detection for all parameters. Univariate analyses determined significant slope ranges for explanatory variables against the 4 responses: ACM, GN, GP, and NPI. Next, all slope ranges were offered into the multivariate models for the same 4 responses using 3 baselines: d -10, -7, and -3 relative to CM detection. In the univariate analysis, no explanatory variables were significant indicators of ACM, whereas at least 1 parameter was significant for each of GN, GP, and NPI models. Superior sensitivity (Se) and specificity (Sp) estimates were observed for the best GP (Se = 82%, Sp = 87%) and NPI (Se = 80%, Sp = 94%) multiple regression models compared with the best ACM (Se = 73%, Sp = 75%) and GN (Se = 71%, Sp = 74%) models. Sensitivity for the GN model was greater at the baseline closest to the day of CM detection (d -3), whereas the opposite was observed for the GP and NPI model as Se was maximized at the d -10 baseline. Based on this screening of relationships, milk and activity sensor data could be used in CM detection systems.


Assuntos
Algoritmos , Comportamento Animal , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Mastite Bovina/diagnóstico , Leite/química , Animais , Bovinos , Contagem de Células/veterinária , Indústria de Laticínios , Condutividade Elétrica , Fazendas , Feminino , Lactação , Lactose/análise , Modelos Lineares , Mastite Bovina/microbiologia , Leite/metabolismo , Leite/normas , Paridade , Gravidez , Sensibilidade e Especificidade
5.
Eur J Neurol ; 26(6): 872-879, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30614594

RESUMO

BACKGROUND AND PURPOSE: Depression is a common neuropsychiatric consequence of stroke. We identified trajectories of depression symptoms in men and women and examined their associations with 10-year all-cause mortality. METHODS: Data were obtained from the South London Stroke Register (1998-2016). Socio-demographic, stroke severity and clinical measures were collected during the acute phase. The Hospital Anxiety and Depression Scale was used to screen for depression at 3 months after stroke and then annually. We used group-based trajectory models to identify trajectories of depression and Cox proportional hazards models to study the risk of mortality in them. RESULTS: We studied 1275 men and 1038 women. Three trajectories of depression symptoms were identified in men: I-M (42.12%), low and stable symptoms; II-M (46.51%), moderate increasing symptoms; and III-M (11.37%), severe persistent symptoms. Four trajectories were identified in women; I-F (29.09%), low symptoms; II-F (49.81%), moderate symptoms; III-F (16.28%), severe symptoms; and IV-F (4.82%), very severe symptoms, all with stable symptoms. The 10-year adjusted mortality hazard ratios in men were: 1.68 [95% confidence interval (CI), 1.38-2.04] and 2.62 (95% CI, 1.97-3.48) for trajectories II-M and III-M, respectively, compared with I-M. In women these were: 1.38 (95% CI, 1.09-1.75), 1.65 (95% CI, 1.23-2.20) and 2.81 (95% CI, 1.90-4.16) for trajectories II-F, III-F and IV-F, respectively, compared with I-F. CONCLUSIONS: Depression trajectories varied independent of sex. Severe symptoms in women were double those in men. Moderate symptoms in men became worse over time. Increased symptoms of depression were associated with higher mortality rates. Data on symptom progression may help a better long-term management of patients with stroke.


Assuntos
Depressão/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/mortalidade , Idoso , Depressão/psicologia , Progressão da Doença , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Risco , Acidente Vascular Cerebral/psicologia , Taxa de Sobrevida
6.
J Dairy Sci ; 102(12): 11233-11249, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606213

RESUMO

Vaccination against coliform mastitis has become part of mastitis control programs in the past 3 decades, as a means of reducing the severity of clinical mastitis. Our study objective was to evaluate the effect of 2 commercially available vaccines on clinical, behavioral, and antibody response following Escherichia coli intramammary challenge in cows near peak lactation. Cows (n = 12 per group) were vaccinated with vaccine 1 (V1) or vaccine 2 (V2) at dry-off, 21 d pre-calving, and 14 d post-calving. Twelve cows served as unvaccinated controls (CTL). Cows were challenged with E. coli in a rear quarter at approximately 100 d in milk. Milk samples were collected pre- and post-challenge to enumerate E. coli and determine somatic cell count. Serum was collected before each vaccination and at d 0, 1, 2, 3, 6, 30, and 60 relative to challenge, to study antibody response. Milk IgA and tumor necrosis factor-α concentrations were determined in whey. Vaginal temperature, cow activity, and milk yield and components were monitored post-challenge. Bacterial count, somatic cell score, milk yield and component decline, vaginal temperature, activity measures, and antibody and cytokine response were analyzed for treatment differences. The effects of parity, breed, and a repeated measure of time were also tested. Seven cows had to be removed from the study post-challenge for antibiotic treatment (CTL and V1, n = 3 each; V2, n = 1), 2 of which were euthanized (both CTL). Vaccinated cows exhibited fever (vaginal temperature ≥39.4°C) 3 h earlier than CTL cows, but we found no differences between treatments for bacterial count, somatic cell score, or milk yield reduction. Vaccinated cows spent more time lying per rest bout 2 d post-challenge, but total daily lying time was not different from CTL cows during the 7 d post-challenge. The vaccines differed in antibody response: V1 cows had greater serum IgG1 and IgG2 post-challenge. A parity effect was also evident: primiparous cows had lower bacterial counts, somatic cell score and a smaller milk yield decline than multiparous cows, but also had lower antibody production. Immunization with either J5 bacterin did not reduce clinical signs of mastitis in cows challenged at 100 d in milk, demonstrating that the effects of J5 vaccination had diminished at peak lactation.


Assuntos
Infecções por Escherichia coli/veterinária , Vacinas contra Escherichia coli/imunologia , Imunogenicidade da Vacina , Mastite Bovina/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Contagem de Células/veterinária , Escherichia coli/imunologia , Vacinas contra Escherichia coli/administração & dosagem , Feminino , Humanos , Imunoglobulina G/sangue , Lactação , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Leite/citologia , Leite/microbiologia , Paridade , Gravidez , Vacinação/veterinária
7.
J Dairy Sci ; 102(12): 11777-11785, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606220

RESUMO

Heat stress abatement is a challenge for dairy producers in the United States, especially in the southern states. Thus, managing heat stress is critical to maintain dairy cow performance in the summer. The ability to employ a metric to measure heat stress and evaluate abatement strategies may benefit dairy producers by providing meaningful feedback on the effectiveness of current and future management strategies with the goal of improving heat stress management. Therefore, this study aimed to explore the use of the summer to winter performance ratio metric to quantify and compare farm performance variables among regions of the United States. Monthly performance data recorded by the Dairy Herd Improvement Association from 2007 to 2016, for all US Dairy Herd Improvement Association herds processing records through Dairy Records Management Systems (Raleigh, NC), were obtained. Season dates were based on the astronomical definition of the Northern Hemisphere with summer as June 21 to September 21 and winter as December 21 to March 19. States were grouped into regions based on climate zone classification. Performance records included a total of 16,573 herds [Northeast (n = 7,955), Midwest (n = 6,555), Northern Plains (n = 305), Southeast (n = 1,370), and Southern Plains (n = 388) regions]. Herd test day performance variables energy-corrected milk, somatic cell score, milk fat and protein percentage, conception rate, heat detection rate, and pregnancy rate in summer and winter were used to calculate summer to winter ratios for each region. The MIXED procedure of SAS 9.4 (SAS Institute Inc., Cary, NC) was used to compare test day performance variables. The effects of year, mean days in milk, mean 150-d milk, mean herd size, and number of milkings per day were included as covariates in the models. Dairy cattle performance in all climate regions was negatively affected by summer heat stress, but some regions greater than others. A difference was also observed among regions when comparing summer to winter ratios for each performance parameter. This indicates that summer performance varies by climate region identified by the summer to winter ratio and demonstrates usefulness of the metric to monitor degree of heat stress based on performance.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Leite/metabolismo , Taxa de Gravidez , Reprodução , Animais , Regulação da Temperatura Corporal , Clima , Fazendas , Feminino , Fertilização , Glicolipídeos/análise , Glicoproteínas/análise , Resposta ao Choque Térmico , Lactação , Gotículas Lipídicas , Leite/química , Proteínas do Leite/análise , Gravidez , Registros , Estações do Ano , Estados Unidos
8.
J Dairy Sci ; 101(1): 413-424, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29128227

RESUMO

Ketosis is one of the most frequently reported metabolic health events in dairy herds. Several genetic analyses of ketosis in dairy cattle have been conducted; however, few have focused specifically on Jersey cattle. The objectives of this research included estimating variance components for susceptibility to ketosis and identification of genomic regions associated with ketosis in Jersey cattle. Voluntary producer-recorded health event data related to ketosis were available from Dairy Records Management Systems (Raleigh, NC). Standardization was implemented to account for the various acronyms used by producers to designate an incidence of ketosis. Events were restricted to the first reported incidence within 60 d after calving in first through fifth parities. After editing, there were a total of 42,233 records from 23,865 cows. A total of 1,750 genotyped animals were used for genomic analyses using 60,671 markers. Because of the binary nature of the trait, a threshold animal model was fitted using THRGIBBS1F90 (version 2.110) using only pedigree information, and genomic information was incorporated using a single-step genomic BLUP approach. Individual single nucleotide polymorphism (SNP) effects and the proportion of variance explained by 10-SNP windows were calculated using postGSf90 (version 1.38). Heritability of susceptibility to ketosis was 0.083 [standard deviation (SD) = 0.021] and 0.078 (SD = 0.018) in pedigree-based and genomic analyses, respectively. The marker with the largest associated effect was located on chromosome 10 at 66.3 Mbp. The 10-SNP window explaining the largest proportion of variance (0.70%) was located on chromosome 6 beginning at 56.1 Mbp. Gene Ontology (GO) and Medical Subject Heading (MeSH) enrichment analyses identified several overrepresented processes and terms related to immune function. Our results indicate that there is a genetic component related to ketosis susceptibility in Jersey cattle and, as such, genetic selection for improved resistance to ketosis is feasible.


Assuntos
Doenças dos Bovinos/genética , Estudo de Associação Genômica Ampla/veterinária , Genoma/genética , Cetose/veterinária , Polimorfismo de Nucleotídeo Único/genética , Animais , Bovinos , Feminino , Genômica , Linhagem , Fenótipo , Seleção Genética
9.
J Dairy Sci ; 101(11): 10151-10167, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30172394

RESUMO

Parturition is often a stressful period, when the incidence of disease is high after calving, which has been associated with an uncontrolled inflammatory response. Therefore, the objective of this study was to test the effect of the administration of a nonsteroidal anti-inflammatory drug (meloxicam) on the behavior, health, and production of peripartum cows. Meloxicam was dosed at 1 mg/kg of body weight, and an empty gel capsule served as a placebo. Both were administered orally with a balling gun. Dairy cows and heifers were randomly assigned to 1 of 3 treatment groups: (1) meloxicam administration before calving, with a placebo administered after calving (MEL-PRE, n = 60), (2) placebo administered before calving, and meloxicam administered after calving (MEL-POST, n = 69), and (3) a placebo administered before calving and after calving (CTL, n = 65). To identify imminent calving events, a vaginal thermometer was inserted approximately 2 wk before the expected calving date and a drop in temperature was used to identify cows close to calving. Calving events were monitored via video cameras, and the amount of time that elapsed between the appearance of the amniotic sac at the vulva until delivery of the calf was used to determine calving difficulty score. Eutocic calving events were defined as cows that calved in ≤70 min, and dystocia was defined as cows that took longer than 70 min to calve. Milk yield and components were measured for the first 15 wk of lactation and accelerometers were used to record activity and lying behaviors. The effects of treatment, breed, parity, calving difficulty, and, when applicable, a repeated measure, along with interaction terms, were analyzed in mixed models. Regardless of the time of administration, dystocic cattle that received meloxicam were less active than dystocic CTL. Dystocic animals displayed more lying bouts on the day of calving and then displayed fewer lying bouts and were less active during the days following calving. No effect of treatment was noted on any health outcomes. Eutocic MEL-PRE animals produced 6.8 kg/d more milk than eutocic CTL. Regardless of calving difficulty, MEL-PRE animals produced more milk fat, protein, and lactose (kg/d) than CTL. In conclusion, meloxicam administration before calving appears promising in increasing milk yield in eutocic cows.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Distocia/veterinária , Meloxicam/administração & dosagem , Leite/metabolismo , Reprodução/efeitos dos fármacos , Animais , Temperatura Corporal , Peso Corporal , Bovinos , Distocia/tratamento farmacológico , Feminino , Nível de Saúde , Lactação/efeitos dos fármacos , Leite/química , Paridade , Parto , Período Periparto , Gravidez , Distribuição Aleatória , Vagina
10.
J Dairy Sci ; 100(11): 9273-9278, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28918146

RESUMO

Group housing of calves can pose a challenge in identifying respiratory disease; therefore, it is necessary to develop tools that can identify these disease events. In this experiment, pre-weaned calves (n = 30) were housed in groups with an automatic calf feeder and were fitted with an accelerometer. Step activity, lying behaviors, and feeding behaviors were recorded to determine the effect of respiratory disease. All calves were health scored twice daily, and calves with respiratory scores ≥5 were diagnosed with respiratory disease (n = 10). Each diseased calf was match paired with a healthy control based on the date of disease diagnosis, breed, and age. Control calves were determined to be healthy if they had respiratory scores ≤4, as well as fecal, navel, and joint scores of 0 or 1. Diseased calves were less active before, on the day of, and after respiratory disease diagnosis. Furthermore, diseased calves had reduced lying frequencies starting 2 d before diagnosis, as well as after diagnosis. Last, diseased calves consumed less milk on the day of diagnosis when compared with healthy controls. Step activity, lying bouts, and milk intake may prove to be a useful tool in identifying respiratory disease under practical farming, but this requires further research.


Assuntos
Comportamento Animal , Doenças dos Bovinos/diagnóstico , Leite , Doenças Respiratórias/veterinária , Animais , Animais Lactentes , Bovinos , Indústria de Laticínios , Dieta/veterinária , Comportamento Alimentar , Feminino , Doenças Respiratórias/diagnóstico
11.
Am J Transplant ; 16(12): 3562-3567, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27376472

RESUMO

Donor-derived coccidioidomycosis has caused unexpected morbidity and mortality in transplant recipients. All proven or probable reports of donor-derived coccidioidomycosis to the Disease Transmission Advisory Committee between 2005 and August 2012 were reviewed. Six reports of proven or probable coccidioidomycosis were discovered. In four of six, the infection was first detected at autopsy in the recipient. In two cases it was first identified in the donor. Twenty-one recipients received organs from these six donors. Transmission occurred in 43% at a median of 30 days posttransplant with a mortality rate of 28.5%. Eleven recipients received preemptive antifungals, seven did not receive treatment, and treatment information was not reported for three recipients. Five of seven who did not receive prophylaxis/treatment died and all 11 who received early therapy survived. Six deaths occurred 14 to 55 days after transplant, with a median of 21 days. For exposed recipients, donor-derived coccidioidomycosis is a significant cause of morbidity and mortality. Evidence of infection in one recipient should prompt immediate evaluation for treatment of all other recipients from the same donor as preemptive treatment was effective. Further studies are needed to decide whether all donors from endemic areas should have routine serologic screening.


Assuntos
Coccidioides/patogenicidade , Coccidioidomicose/transmissão , Transmissão de Doença Infecciosa , Transplante de Órgãos/efeitos adversos , Doadores de Tecidos , Comitês Consultivos , Coccidioidomicose/epidemiologia , Coccidioidomicose/etiologia , Seleção do Doador , Humanos , Segurança do Paciente , Prognóstico , Medição de Risco , Obtenção de Tecidos e Órgãos , Transplantados , Estados Unidos/epidemiologia
12.
14.
J Dairy Sci ; 99(11): 9109-9113, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27614829

RESUMO

Calf behaviors such as step activity, lying bouts, and lying time may be an indicator of calf health and welfare. To reduce time-consuming visual observations, the use of behavioral monitoring systems have been developed to capture these data. Previous studies have validated lying behaviors using an accelerometer (HPG; HOBO Pendant G data logger, Onset Computer Corp., Bourne, MA) in calves. However, the HPG does not measure step activity. The objectives of this study were to (1) validate step activity, lying bouts, and lying time of AfiTag II (AT2; AfiTag II, Afimilk Ltd., Kibbutz Afikim, Israel) to observations from video, and (2) to compare the behavioral data from AT2 to the HPG. Calves (n=5) were group housed with an automatic calf feeder. Video cameras were installed at both sides of the pen, and observations were analyzed for 7h/calf. The AT2 and the HPG were both attached to the lateral side of the right rear leg of 5 calves, and data were recorded for 10 d. The full 10-d data set was used to examine correlations for lying bouts and lying time between AT2 and the HPG. The HPG was set at a 60-s sampling interval and the output was analyzed both unfiltered as well as utilizing a 1-min event filter to remove potentially erroneous readings. The AT2 recorded step activity, lying bouts, and lying time, and summarized these behaviors in 15-min periods. The AT2 recorded lying time in 3-min intervals, which were then automatically summarized in 15-min periods. The correlations of step activity, lying bouts, and lying time between video recordings and AT2 were 0.99. For the second objective, correlations between AT2 and the HPG were 0.99 for lying time and 0.93 for lying bouts. The 1-min event filter resulted in a 0.03 improvement in correlations for lying bouts between the HPG and AT2. The high correlation between video recordings and AT2 suggest that this device can be used to measure step activity, lying time, and lying bouts in unweaned dairy calves housed in groups.


Assuntos
Comportamento Animal , Abrigo para Animais , Animais , Bovinos , Monitorização Fisiológica , Fatores de Tempo , Gravação em Vídeo
15.
J Dairy Sci ; 99(5): 3979-3994, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26923041

RESUMO

Vaccination contributes to improved herd health and production. Boosting immune development at a young age may have long-term effects by enhancing vaccine immune response and efficacy. In the bovine, colostrum is the sole source of maternal immunity, having a substantial effect on health status in the neonate. To date, colostral antibody concentration is used to evaluate colostrum quality. However, colostrum also contains proteins and cells, which may affect immune development and future responses to vaccines. To determine the effect of maternal colostral cells on immune development, 37 female Holstein and Jersey dairy calves were bottle-fed 4 quarts total of whole colostrum (WC) or cell-free colostrum (CFC) at birth. Calves were vaccinated with 2 series of multivalent vaccines. Series A consisted of vaccines given between 1 and 4mo of life. Series B consisted of vaccines given between 5 and 10mo of life. Calf peripheral blood samples were obtained before each vaccination series and monthly for 3mo after each vaccination series. Cellular blood parameters were determined by flow cytometry. Quantitative real-time PCR was used to determine cytokine gene expression in peripheral blood mononuclear cells before vaccination series B and once a month for 2mo after vaccination series B. Calves fed CFC had fewer numbers of B cells in mo 2 after vaccination series A when compared with WC-fed calves. Calves fed CFC had decreased gene expression levels of IL-2 in mo 1 and numbers of CD4(+)CD62L(+)CD45RO(-) and CD4(+)CD62L(+)CD45RO(+) T cells in mo 0 and 1 after vaccination series B as compared with WC-fed calves. Our findings indicate a greater response to vaccines up to 6 to 10mo post-WC feeding when compared with CFC. These data suggest that adoptive transfer of maternal colostral cells at birth has a long-term effect on development of the neonatal immune system.


Assuntos
Animais Recém-Nascidos/imunologia , Bovinos/imunologia , Colostro/imunologia , Sistema Imunitário/crescimento & desenvolvimento , Imunidade Inata , Vacinação/veterinária , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Bovinos/crescimento & desenvolvimento , Sistema Livre de Células/imunologia , Feminino
16.
J Dairy Sci ; 98(6): 3729-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25795487

RESUMO

Mortality and decreased weight gain resulting from infection and disease in dairy calves are problems within the dairy industry. The bovine neonate relies solely on colostrum to acquire antibodies through passive transfer. To date, colostrum quality is determined by the concentration of antibodies. However, proteins and cells in the colostrum might also enhance immune development in the neonate. To determine the effect of maternal colostral immune cells on calf health and immune status, maternal colostrum was fed either fresh or after lysis of cells by flash-freezing in liquid nitrogen. Thirty-seven female Holstein and Jersey dairy calves were fed 4 quarts total of whole colostrum (WC) or cell-free colostrum (CFC) at birth. Respiratory and fecal scores were measured from birth to d 45 of life. Calf peripheral blood samples were obtained before and after feeding colostrum as well as on d 1, 3, 7, 14, 21, and 28 of life. Peripheral blood mononuclear cells were collected and analyzed for cellular parameters by flow cytometry. Total respiratory scores were greater in CFC-fed calves compared with WC-fed calves on d 38 of life. There were fewer CD4+ T cells and CD4+CD62L+CD45RO- T cells on d 1 and fewer CD4+CD62L+CD45RO+ T cells on d 1 and 3 in CFC-fed calves compared with WC-fed calves. Compared with WC-fed calves, CFC-fed calves had a greater percentage of CD4+CD62L-CD45RO+ T cells on d 0.25, 1, 3, and 7, and a greater percentage of monocytes on d 7. Our data suggest that colostral cells adoptively transfer and enhance neonatal immunity during the first month of life.


Assuntos
Animais Recém-Nascidos , Bovinos/imunologia , Colostro/citologia , Colostro/imunologia , Animais , Líquidos Corporais , Bovinos/fisiologia , Feminino , Imunoglobulina G/sangue , Leucócitos Mononucleares , Gravidez , Aumento de Peso
17.
J Neurol Neurosurg Psychiatry ; 85(5): 514-21, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24163430

RESUMO

BACKGROUND: Post-stroke depression is a frequent chronic and recurrent problem that starts shortly after stroke and affects patients in the long term. The health outcomes of depression after stroke are unclear. AIMS: (1) To investigate the associations between depression at 3 months and mortality, stroke recurrence, disability, cognitive impairment, anxiety and quality of life (QoL), up to 5 years post-stroke. (2) To investigate these associations in patients recovering from depression by year 1. (3) To investigate associations between depression at 5 years and these outcomes up to 10 years. METHODS: Data from the South London Stroke Register (1997-2010) were used. Patients (n at registration=3240) were assessed at stroke onset, 3 months after stroke and annually thereafter. Baseline data included sociodemographics and stroke severity measures. Follow-up assessments included anxiety and depression (Hospital Anxiety and Depression scale), disability, QoL and stroke recurrence. Multivariable regression models adjusted for age, gender, ethnicity, stroke severity and disability were used to investigate the association between depression and outcomes at follow-up. RESULTS: Depression at 3 months was associated with: increased mortality (HR: 1.27 (1.04 to 1.55)), disability (RRs up to 4.71 (2.96 to 7.48)), anxiety (ORs up to 3.49 (1.71 to 7.12)) and lower QoL (coefficients up to -8.16 (-10.23-6.15)) up to year 5. Recovery from depression by 1 year did not alter these risks to 5 years. Depression in year 5 was associated with anxiety (ORs up to 4.06 (1.92 to 8.58)) and QoL (coefficients up to -11.36 (-14.86 to -7.85)) up to year 10. CONCLUSIONS: Depression is independently associated with poor health outcomes.


Assuntos
Transtorno Depressivo/epidemiologia , Sistema de Registros , Acidente Vascular Cerebral/psicologia , Idoso , Transtornos de Ansiedade/epidemiologia , Transtornos Cognitivos/epidemiologia , Feminino , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Recidiva , Fatores Socioeconômicos , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo
18.
J Dairy Sci ; 97(4): 2213-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24534505

RESUMO

Klebsiella pneumoniae mastitis in dairy cattle is generally due to an opportunistic infection from the environment, resulting in large heterogeneity among mastitis-causing strains within a herd. However, in mastitis outbreaks in 4 herds, several strains of K. pneumoniae were identified as the cause of infection in multiple cows, suggesting increased ability to either cause disease or evade host defenses. In this study, differences in capsule formation and immune evasion were compared in 5 pairs of K. pneumoniae strains, where one strain in each pair was associated with multiple cases of mastitis and the other with a single case of mastitis. Production of capsular polysaccharide, ability to evade killing by polymorphonuclear neutrophilic leukocytes (PMNL), and the relationship between the 2 were evaluated for each strain grown in broth or milk. Growth of isolates in skim milk increased capsule size and ability to evade killing by PMNL, depending on strain type. Specifically, strains associated with multiple cases of mastitis had increased capsule size in skim milk. Strains associated with single cases of mastitis were better able to evade killing by PMNL when grown in skim milk. Our results, although preliminary, suggest that the 2 groups of strains may constitute different subpopulations of K. pneumoniae. However, our findings do not indicate that capsule or evasions of killing by PMNL explain increased mastitis outbreaks with Klebsiella. Further work will explain the enhanced ability of some strains to cause mastitis in dairy cows.


Assuntos
Surtos de Doenças/veterinária , Klebsiella pneumoniae/fisiologia , Klebsiella pneumoniae/patogenicidade , Mastite Bovina/epidemiologia , Fatores de Virulência/genética , Animais , Bovinos , Feminino , Infecções por Klebsiella/veterinária , Mastite Bovina/microbiologia , Mastite Bovina/transmissão , New York/epidemiologia , Fatores de Virulência/metabolismo
19.
Phys Rev Lett ; 111(11): 117201, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24074116

RESUMO

We present a new tool for imaging spin properties. We show that a spatially averaged spin signal, measured as a function of a scanned magnetic probe's position, contains information about the local spin properties. In this first demonstration we map the injected spin density in GaAs by measuring spin photoluminescence with a resolution of 1.2 µm. The ultimate limit of the technique is set by the gradient of the probe's field, allowing for a resolution beyond the optical diffraction limit. Such probes can also be integrated with other detection methods. This generality allows the technique to be extended to buried interfaces and optically inactive materials.

20.
J Dairy Sci ; 96(5): 2847-56, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23522672

RESUMO

The objectives of this study were to (1) evaluate the use of a pressure algometer and an automated rumination monitoring system to assess changes in pain sensitivity and rumination time in response to endotoxin-induced clinical mastitis and (2) evaluate the effect of the nonsteroidal antiinflammatory drug meloxicam on pain sensitivity and rumination time, as well as other clinical signs, in dairy cattle with endotoxin-induced clinical mastitis. Clinical mastitis was induced in 12 primiparous and 12 multiparous lactating dairy cows by intramammary infusion of 25 µg of Escherichia coli lipopolysaccharide (LPS) into 1 uninfected quarter. Immediately after, half the cows were injected subcutaneously with meloxicam (treated group) and half with the same volume of a placebo solution (control group). Pain sensitivity was assessed by measuring the difference in pressure required to elicit a response on the control and challenged quarter using an algometer 3 d before, immediately before, and at 3, 6, 12, and 24h after LPS infusion and either meloxicam or placebo injection. Rumination was continuously monitored from 2 d before to 3 d after LPS infusion using rumination loggers. Udder edema, body temperature, somatic cell score, and dry matter intake were also monitored to evaluate the occurrence and the duration of the inflammation after LPS infusion. In control animals, the difference in the pressure applied to the control and challenged quarters (control - challenged quarter) increased by 1.1 ± 0.4 kg of force 6h after LPS infusion compared with the baseline, suggesting an increase in pain sensitivity in the challenged quarter. Neither the LPS infusion nor the meloxicam treatment had an effect on daily rumination time. However, the rumination diurnal pattern on the day of LPS infusion showed an overall deviation from the baseline pattern. Cows spent less time ruminating in the hours following LPS infusion and more time ruminating later in the day. Meloxicam did not alter somatic cell score or dry matter intake. However, meloxicam-treated animals had less udder edema and a lower body temperature in the hours following LPS infusion compared with control animals. In conclusion, pressure algometers and rumination loggers show promise as tools to detect mastitis and monitor recovery on farm. Further, meloxicam has a beneficial effect in relieving pain and decreasing udder edema and body temperature in LPS-induced clinical mastitis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Digestão/efeitos dos fármacos , Mastite Bovina/tratamento farmacológico , Manejo da Dor/veterinária , Tiazinas/uso terapêutico , Tiazóis/uso terapêutico , Animais , Bovinos , Feminino , Lipopolissacarídeos/farmacologia , Mastite Bovina/induzido quimicamente , Meloxicam , Dor/tratamento farmacológico , Dor/veterinária , Manejo da Dor/métodos , Medição da Dor/veterinária
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