Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Más filtros











Intervalo de año de publicación
1.
J Dairy Sci ; 105(5): 4421-4433, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35282915

RESUMEN

Bovine anaplasmosis causes considerable economic losses in dairy cattle production systems worldwide, ranging from $300 million to $900 million annually. It is commonly detected through rectal temperature, blood smear microscopy, and packed cell volume (PCV). Such methodologies are laborious, costly, and difficult to systematically implement in large-scale operations. The objectives of this study were to evaluate (1) rumination and activity data collected by Hr-Tag sensors (SCR Engineers Ltd.) in heifer calves exposed to anaplasmosis; and (2) the predictive ability of recurrent neural networks in early identification of anaplasmosis. Additionally, we aimed to investigate the effect of time series length before disease diagnosis (5, 7, 10, or 12 consecutive days) on the predictive performance of recurrent neural networks, and how early anaplasmosis disease can be detected in dairy calves (5, 3, and 1 d in advance). Twenty-three heifer calves aged 119 ± 15 (mean ± SD) d and weighing 148 ± 20 kg of body weight were challenged with 2 × 107 erythrocytes infected with UFMG1 strain (GenBank no. EU676176) isolated from Anaplasma marginale. After inoculation, animals were monitored daily by assessing PCV. The lowest PCV value (14 ± 1.8%) and the finding of rickettsia on blood smears were used as a criterion to classify an animal as sick (d 0). Rumination and activity data were collected continuously and automatically at 2-h intervals, using SCR Heatime Hr-Tag collars. Two time series were built including last sequence of -5, -7, -10, or -12 d preceding d 0 or a sequence of 5, 7, 10, or 12 d randomly selected in a window from -50 to -15 d before d 0 to ensure a sequence of days in which PCV was considered normal (32 ± 2.4%). Long short-term memory was used as a predictive approach, and a leave-one-animal-out cross-validation (LOAOCV) was used to assess prediction quality. Anaplasmosis disease reduced 34 and 11% of rumination and activity, respectively. The accuracy, sensitivity, and specificity of long short-term memory in detecting anaplasmosis ranged from 87 to 98%, 83 to 100%, and 83 to 100%, respectively, using rumination data. For activity data, the accuracy, sensitivity, and specificity varied from 70 to 98%, 61 to 100%, and 74 to 100%, respectively. Predictive performance did not improve when combining rumination and activity. The use of longer time-series did not improve the performance of models to predict anaplasmosis. The accuracy and sensitivity in predicting anaplasmosis up to 3 d before clinical diagnosis (d 0) were greater than 80%, confirming the possibility for early identification of anaplasmosis disease. These findings indicate the great potential of wearable sensors in early identification of anaplasmosis diseases. This could positively affect the profitability of dairy farmers and animal welfare.


Asunto(s)
Anaplasma marginale , Anaplasmosis , Enfermedades de los Bovinos , Anaplasmosis/diagnóstico , Anaplasmosis/microbiología , Animales , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/microbiología , Eritrocitos , Femenino , Vacunación/veterinaria
2.
PLoS One ; 15(7): e0236118, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32667943

RESUMEN

The objective of this study was to evaluate whether pre-weaning heifer calves divergent for residual feed intake (RFI) or residual feed intake and body weight gain (RIG) exhibit differences in thermography, blood, and ruminal parameters. Thirty-two Gyr heifer calves were enrolled in a 63-d trial and classified into 2 feed efficiency (FE) groups based on RFI and RIG (mean ± 0.5 SD). The groups were classified as high efficiency (HE) RFI (HE RFI, n = 9), HE RIG (HE RIG, n = 10), low efficiency (LE) RFI (LE RFI, n = 10), and LE RIG (LE RIG, n = 11). The amount of whole milk provided for each calf was calculated based on their metabolic weight at birth (42% x BW0.75). The liquid diet was divided into two meals at 0700 and 1400 h. The total solid diet (TSD) was composed of 92% concentrate and 8% of Tifton 85 hay chopped in 5-cm lengths, as fed. Intake was measured daily. Blood concentrations of insulin, beta hydroxybutyrate, urea, and glucose, and ruminal pH, N-NH3, and volatile fatty acids (VFA) were evaluated at 14, 28, 42, 56, and 70 days of age. Thermal images of the calves were taken with an infrared camera (FLIR T420, FLIR Systems Inc., Wilsonville, OR) on d 56 (±3) at 0600 h, before the morning feeding. Total VFA concentration and propionate as % of total VFA were 24.2% and 22.2% lower in HE RFI compared to LE RFI calves, respectively. On the other hand, acetate as % of total VFA was 10.6% greater in HE RFI than LE RFI calves. Blood urea concentration tended to be greater in LE RFI than HE RFI calves. High efficiency HE RIG tended to have 6.8% greater acetate and 15.4% lower propionate as % of total VFA than LE RIG. Blood insulin concentration was greater and blood glucose tended to be greater for LE RIG than HE RIG group. Low efficiency RIG group had greater left rib, left flank, and anus surface temperature measured by infrared thermography than the HE RIG group. Differences in ruminal fermentation do not seem to be associated with pre-weaning calves efficiency, while differences in protein metabolism seem to affect RFI during this phase. Infrared thermography appears to be correlated to RIG in pre-weaning heifer calves.


Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Conducta Alimentaria/fisiología , Termogénesis , Destete , Aumento de Peso , Animales , Células Sanguíneas/metabolismo , Bovinos , Ingestión de Energía , Rumiantes/metabolismo , Termografía
3.
Rev. bras. plantas med ; Rev. bras. plantas med;14(2): 335-343, 2012. ilus, tab
Artículo en Portugués | LILACS | ID: lil-650675

RESUMEN

O Brasil está entre os principais exportadores de poaia [Psychotria ipecacuanha (Brot.) Stoves] seguido do Panamá e Costa Rica. A poaia brasileira apresenta alto valor farmacológico das raízes devido aos teores de emetina e cefalina. Este trabalho teve como objetivo descrever como as famílias de poaieiros mantém a memória cultural sobre a Psychotria ipecacuanha (Brot.) Stoves. As informações foram coletadas no município de Cáceres, Mato Grosso, através de entrevista estruturada e observação participante com 20 homens e 10 mulheres, de faixa etária de 45 a 86 anos. Foram citadas as formas de utilização na alimentação para animais, inseticida, carrapaticida, emético, contra diarréias, para alívio de dor de cabeça, contra malária, bronquite e dor no estômago. A raiz é a parte mais usada e a forma de preparo é tintura ou misturada ao fumo, ao vinho ou à cachaça. Poucos entrevistados passaram aos filhos o conhecimento sobre a P. ipecacuanha. A memória cultural sobre a P. ipecacuanha deve-se a vivência, extração e comercialização da planta, e por ouvir as conversas dos pais com amigos. A perda de conhecimento associado a poaia é causada pelo êxodo rural, destruição do habitat com o desmatamento e ocupação agrícola. A extinção da espécie na região contribui para a erosão cultural.


Brazil is among the leading exporters of ipecac [Psychotria ipecacuanha (Brot.) Stoves], followed by Panama and Costa Rica. The roots of Brazilian ipecac have high pharmacological value due to their levels of emetine and cephalin. This study aimed to describe how families of "poaieiros" maintain the cultural memory of Psychotria ipecacuanha (Brot.) Stoves. Information was collected in the city of Cáceres, Mato Grosso State, Brazil, through structured interviews and participating observation involving 20 men and 10 women aged from 45 to 86 years. The cited forms of use were in animal nutrition, as insecticide, acaricide, emetic, against diarrhea, relief from headache, and against malaria, bronchitis and stomach ache. The root is the most used part and its preparation form is tincture or mixed with tobacco, wine or sugarcane. Few interviewees transmitted to their children the knowledge of P. ipecacuanha. The cultural memory of P. ipecacuanha is due to experience, extraction and marketing of the plant, as well as to hearing conversations between parents and friends. The loss of knowledge associated with ipecac is caused by rural exodus, destruction of its habitat due to deforestation and agricultural occupation. The extinction of this species in the region contributes to cultural erosion.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Ipecacuanha/historia , Ipeca/clasificación , Antropología Cultural/instrumentación , Etnobotánica/métodos , Pradera
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA