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1.
J Dairy Sci ; 105(5): 4421-4433, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35282915

RESUMO

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.


Assuntos
Anaplasma marginale , Anaplasmose , Doenças dos Bovinos , Anaplasmose/diagnóstico , Anaplasmose/microbiologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Eritrócitos , Feminino , Vacinação/veterinária
2.
PLoS One ; 15(7): e0236118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667943

RESUMO

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.


Assuntos
Ração Animal/análise , Dieta/veterinária , Comportamento Alimentar/fisiologia , Termogênese , Desmame , Aumento de Peso , Animais , Células Sanguíneas/metabolismo , Bovinos , Ingestão de Energia , Ruminantes/metabolismo , Termografia
3.
Rev. bras. plantas med ; 14(2): 335-343, 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-650675

RESUMO

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.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Ipecacuanha/história , Ipeca/classificação , Antropologia Cultural/instrumentação , Etnobotânica/métodos , Pradaria
4.
Clin Exp Hypertens ; 24(5): 383-96, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12109778

RESUMO

The present study examined intestinal dopaminergic activity and its response to high salt (HS, 1% NaCl over a period of 24 hours) intake in obese (OZR) and lean Zucker rats (LZR). The basal Na+,K+-ATPase activity (nmol Pi/mg protein/min) in the jejunum of OZR was higher than in LZR on normal salt (NS) (OZR-NS = 111.3 +/- 6.0 vs. LZR-NS = 88.0 +/- 8.3). With the increase in salt intake, the basal Na+,K+-ATPase activity significantly increased in both animals (OZR-HS = 145.9 +/- 11.8; LZR-HS = 108.8 +/- 6.7). SKF 38393 (10 nM), a specific D1-like dopamine receptor agonist, inhibited the jejunal Na+,K+-ATPase activity in OZR on HS intake, but failed to inhibit enzyme activity in OZR on NS intake and LZR on NS and HS intakes. The aromatic L-amino acid decarboxylase (AADC) activity in OZR was lower than in LZR on NS intake. The HS intake increased AADC activity in OZR, but not in LZR. During the NS intake the jejunal monoamine oxidase (MAO) activity in OZR was similar to that in LZR. The HS intake significantly decreased MAO activity in both OZR and LZR. The jejunal COMT activity in OZR was higher than in LZR on NS intake. The HS intake reduced COMT activity in OZR but not LZR. It is concluded that inhibition of jejunal Na+,K+-ATPase activity through D1 dopamine receptors is dependent on salt intake in OZR, whereas in LZR, the enzyme failed to respond to the activation of D1 dopamine receptors irrespective of their salt intake.


Assuntos
Dopamina/metabolismo , Hipertensão Renal/metabolismo , Jejuno/enzimologia , Obesidade/metabolismo , Cloreto de Sódio na Dieta/farmacologia , Animais , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Catecol O-Metiltransferase/metabolismo , Nefropatias Diabéticas/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Hiperglicemia/metabolismo , Jejuno/efeitos dos fármacos , Levodopa/metabolismo , Masculino , Monoaminoxidase/metabolismo , Ratos , Ratos Zucker , ATPase Trocadora de Sódio-Potássio/metabolismo
5.
Clin Exp Hypertens ; 22(5): 455-69, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10937838

RESUMO

The present study evaluated the activity of jejunal Na+-K+-ATPase and its sensitivity to inhibition by dopamine in spontaneous hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats during low (LS), normal (NS) and high (HS) salt intake. Basal jejunal Na+-K+-ATPase activity in SHR on LS intake was higher than in WKY rats. Jejunal Na+-K+-ATPase activity in WKY rats, but not in SHR, on LS intake was significantly reduced (20% decrease) by dopamine (1 microM) and SKF 38393 (10 nM), but not quinerolane (10 nM), this being antagonized the D1 receptor antagonist (SKF 83566). Changing from LS to NS or HS intake in WKY rats increased basal jejunal Na+-K+-ATPase activity and attenuated the inhibitory effect of dopamine. In SHR, changing from LS to NS or HS intake increased basal jejunal Na+-K+-ATPase activity. Basal renal Na+-K+-ATPase activity in SHR on LS intake was similar to that in WKY rats and was insensitive to inhibition by dopamine. Changing from LS to NS or HS intake in WKY rats increased basal renal Na+-K+-ATPase activity without affecting the inhibitory effect of dopamine. In SHR, changing from LS to NS or HS intake failed to alter basal renal Na+-K+-ATPase activity. It is concluded that inhibition of jejunal Na+-K+ ATPase activity by D1 dopamine receptor activation is dependent on salt intake in WKY rats, and SHR animals fail to respond to dopamine, irrespective of their salt intake.


Assuntos
2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/análogos & derivados , Dopamina/farmacologia , Hipertensão/enzimologia , Jejuno/efeitos dos fármacos , Jejuno/enzimologia , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/enzimologia , Sódio na Dieta/administração & dosagem , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Animais , Dieta Hipossódica , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Inibidores Enzimáticos/farmacologia , Hipertensão/dietoterapia , Técnicas In Vitro , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptores de Dopamina D1/efeitos dos fármacos , Receptores de Dopamina D1/metabolismo , Sulpirida/farmacologia
6.
Am J Physiol ; 275(6): G1317-23, 1998 12.
Artigo em Inglês | MEDLINE | ID: mdl-9843768

RESUMO

During high-salt diet endogenous dopamine (DA) reduces jejunal sodium transport in young but not in adult rats. This study was designed to evaluate whether this effect is mediated, at the cellular level, by inhibition of Na+-K+-ATPase activity. Enzyme activity was determined in isolated jejunal cells by the rate of [gamma-32P]ATP hydrolysis. Cells were obtained from weanling and adult rats fed either with high- or normal-salt diet. In 20-day-old but not in 40-day-old rats Na+-K+-ATPase activity was significantly reduced during high-salt diet. This inhibition was abolished by a blocker of DA synthesis. The decreased activity was associated with a decreased alpha1-subunit at the plasma membrane. During high-salt diet there was an increase in DA content in jejunal cells from 20-day-old rats, associated with a parallel decrease in 5-hydroxytryptamine, compared with normal-salt diet. In 40-day-old rats, however, the catecholamine level remained unchanged during high-salt diet. Incubation of isolated jejunal cells with DA resulted in a dose-dependent inhibition of Na+-K+-ATPase activity in 20- but not in 40-day-old rats. We conclude that during high-salt diet, jejunal Na+-K+-ATPase in 20-day-old rats is inhibited, and this effect is likely to be mediated by locally formed DA.


Assuntos
Envelhecimento/metabolismo , Dieta Hipossódica , Dopamina/fisiologia , Jejuno/enzimologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Absorção/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Dopamina/metabolismo , Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Hidrólise , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Jejuno/citologia , Jejuno/metabolismo , Levodopa/metabolismo , Norepinefrina/metabolismo , Ratos , Ratos Sprague-Dawley , Valores de Referência , Serotonina/metabolismo , Sódio/farmacocinética , ATPase Trocadora de Sódio-Potássio/metabolismo
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