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1.
Animal ; 18(7): 101211, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38935984

RESUMO

Feed efficiency is an important trait of dairy production. However, assessing feed efficiency is constrained by the associated cost and difficulty in measuring individual feed intake, especially on pastures. The objective of this study was to investigate short-term feed efficiency traits of herbage-fed dairy cows and screening of potential biomarkers (n = 238). Derived feed efficiency traits were ratio-based (i.e., feed conversion ratio (FCR) and N use efficiency (NUE)) or residual-based (i.e., residual feed intake (RFI), residual energy intake (REI), and residual N intake (RNI)). Thirty-eight Holstein and 16 Swiss Fleckvieh dairy cows underwent a 7-d measurement period during mid- and/or late-lactation. The experimental data (n = 100 measurement points) covered different lactational and herbage-fed system situations: mid-lactation grazing (n = 56), late-lactation grazing (n = 28), and late-lactation barn feeding (n = 16). During each measuring period, the individual herbage intake of each cow was estimated using the n-alkane marker technique. For each cow, biomarkers representing milk constituents (n = 109), animal characteristics (n = 13), behaviour, and activity (n = 46), breath emissions (n = 3), blood constituents (n = 35), surface, and rectal temperature (n = 29), hair cortisol (n = 1), and near-infrared (NIR) spectra of faeces and milk (n = 2) were obtained. The relationships between biomarkers and efficiency traits were statistically analysed with univariate linear regression and for NIR spectra using partial least squares regression with feed efficiency traits. The feed efficiency traits were interrelated with each other (r: -0.57 to -0.86 and 0.49-0.81). The biomarkers showed varying R2 values in explaining the variability of feed efficiency traits (FCR: 0.00-0.66, NUE: 0.00-0.74, RFI: 0.00-0.56, REI: 0.00-0.69, RNI: 0.00-0.89). Overall, the feed efficiency traits were best explained by NIR spectral characteristics of milk and faeces (R2: 0.25-0.89). Biomarkers show potential for predicting feed efficiency in herbage-fed dairy cows. NIR spectra data analysis of milk and faeces presents a promising method for estimating individual feed efficiency upon further validation of prediction models. Future applications will depend on the ability to improve the robustness of biomarkers to predict feed efficiency in a greater variety of environments (locations), managing conditions, feeding systems, production intensities, and other aspects.

2.
Animal ; 18(3): 101097, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38401327

RESUMO

Exposure to direct solar radiation, high ambient temperature, lack of wind movement, coupled with own metabolic heat production, makes grazing dairy cows vulnerable to heat stress. In pastures, it would be beneficial to monitor heat stress by observable changes in behaviour. We hypothesised that grazing dairy cows exhibit behavioural changes due to increasing heat load in temperate climate. Over two consecutive summers, 38 full-time grazing Holstein dairy cows were investigated in 12 experimental periods of up to 3 consecutive days where the cows were repeatedly exposed to various levels of moderate heat load determined by the comprehensive climate index (CCI). The CCI defines the ambient climate conditions, combining air temperature, relative humidity, solar radiation and wind speed. Vaginal temperature (VT) was automatically measured as an indicator of heat stress. In addition, as a less invasive method, we investigated if reticular temperature (RET) can be indicative of heat stress on pastures. Walking activity, lying-, feeding, and ruminating durations were recorded continuously with sensors. Respiration rate (RR), proximity to and competition at the water trough, social licking, self-licking, inter-individual distance, and fly intensity were directly observed. Data were analysed in the morning (0900-1100 h) and during the hottest time of day when cows were on pasture (1230-1430 h). The VT and RET showed similar patterns in relation to the CCI, suggesting that RET can be suitable for continuous monitoring of heat stress on pastures. In the morning, the cow's VT and RET did not relevantly react to the CCI. During the period 1230-1430 h, the cow's mean VT (mean vaginal temperature (VTMEAN); range: 37.7-40.3 °C) and mean RET (mean reticular temperature; range: 37.0-41.1 °C) were positively related to the mean CCI (mean comprehensive climate index) in this period (mean ± SD: 25.9 ± 5.71 °C). For cows with greater VTMEAN, an increased mean RR and decreased durations of walking, lying, feeding, and ruminating were found. These cows were also more likely to be in proximity to the water trough and to have small inter-individual distances. Changes in these traits seem to reflect behavioural adaptations to heat stress in a temperate climate and could be used to detect the heat stress in individual dairy cows on pastures.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Feminino , Bovinos , Animais , Temperatura Corporal/fisiologia , Lactação/fisiologia , Temperatura , Temperatura Alta , Resposta ao Choque Térmico , Transtornos de Estresse por Calor/veterinária , Transtornos de Estresse por Calor/metabolismo , Água/metabolismo , Umidade , Leite/metabolismo , Doenças dos Bovinos/metabolismo
3.
BMC Psychiatry ; 23(1): 591, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582695

RESUMO

BACKGROUND: Emotion regulation difficulties underlie several psychiatric conditions, and treatments that focus on improving emotion regulation can have an effect on a broad range of symptoms. However, participants' in-depth experiences of participating in emotion regulation treatments have not been much studied. In this qualitative study, we investigated participants' experiences of a joint emotion regulation group skills training in a child and adolescent psychiatric outpatient setting. METHODS: Twenty-one participants (10 adolescents and 11 parents) were interviewed about their experiences after they had participated in a seven-session transdiagnostic emotion regulation skills training for adolescents and parents. The aim of the skills training was to decrease emotion regulation difficulties, increase emotional awareness, reduce psychiatric symptoms, and enhance quality of life. The skills training consisted of psychoeducation about emotions and skills for regulating emotions. The interviews were transcribed and analysed using reflexive thematic analysis. RESULTS: The analysis resulted in three overarching themes: Parent - Child processes, Individual processes, and Group processes. The result showed that participants considered an improved parent-child relationship to be the main outcome. Increased knowledge, emotion regulation skills and behavioural change were conceptualised as both mechanisms of change and outcomes. The group format, and the fact that parents and adolescents participated together, were seen as facilitators. Furthermore, the participants experienced targeting emotions in skills training as meaningful and helpful. CONCLUSION: The results highlight the potential benefits of providing emotion regulation skills training for adolescents and parents together in a group format to improve the parent-child relationship and enable the opportunity to learn skills.


Assuntos
Regulação Emocional , Humanos , Adolescente , Qualidade de Vida , Pais/psicologia , Emoções , Relações Pais-Filho
4.
J Dairy Sci ; 106(10): 6816-6833, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37500448

RESUMO

This study investigated the effects of acacia (extract of Acacia mearnsii) and sainfoin (Onobrychis viciifolia) as condensed tannin (CT)-rich sources on ruminal and manure methane (CH4) emissions in comparison with non-CT silages characterized by different contents of the cell wall and water-soluble carbohydrates. In a 3 × 6 incomplete Latin square design, 30 Holstein cows (63 ± 23 d in milk; mean ± SD; 33.8 ± 7.6 kg of milk per day, body weight 642 ± 81 kg) were provided with ad libitum access to 1 of 6 total mixed rations comprising 790 g of silage and 210 g of concentrate per kilogram of dry matter (DM). The silages were either rich in sainfoin [neutral detergent fiber (NDF): 349 g/kg of DM], perennial ryegrass (NDF: 420 g/kg of DM), or red clover (NDF: 357 g/kg of DM). Each silage was supplemented with 20 g/kg (of total diet DM) of acacia or straw meal. Feed intake and milk yield were recorded daily. Milk composition and ruminal fluid characteristics and microbiota were analyzed. The individual ruminal CH4 production was determined using the GreenFeed system, and CH4 emissions from the manure of cows fed the same diets were measured in a parallel experiment over 30 d at 25°C using a dynamic flux chamber. The CT sources did not reduce CH4 yield or emission intensity. Acacia reduced milk production (from 26.3 to 23.2 kg/d) and DM intake (from 19.7 to 16.7 kg/d) when supplemented with ryegrass, and both CT sources reduced the milk protein content and yield. Acacia supplementation and ryegrass silage reduced the ruminal acetate:propionate ratio. Furthermore, during acacia treatment, the abundance of Methanobrevibacter archaea tended to be lower and that of Thermoplasmata was higher. Acacia reduced the CH4 emissions from manure for the ryegrass group by 17% but not for the sainfoin and clover groups. Feeding sainfoin silage resulted in the lowest manure-derived CH4 emissions (-47% compared with ryegrass). In conclusion, acacia reduced ruminal CH4 production by 10%, but not emission intensity, and the mitigation effect of sainfoin depended on the silage to which it was compared. Because mitigation was partially associated with animal productivity losses, careful evaluation is required before the implementation of tanniferous feeds in farm practice.


Assuntos
Acacia , Proantocianidinas , Feminino , Bovinos , Animais , Esterco , Lactação , Silagem/análise , Acacia/metabolismo , Metano/metabolismo , Digestão , Zea mays/metabolismo , Dieta/veterinária , Nutrientes , Rúmen/metabolismo
5.
Animal ; 17(3): 100718, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36827848

RESUMO

Even in temperate climate regions, an increase in ambient temperature and exposure to solar radiation can cause heat stress in lactating dairy cows. We hypothesised that grazing dairy cows exhibit short-term physiological changes due to increasing heat load under moderate climate conditions. Over two consecutive summers, 38 lactating Holstein dairy cows were studied in a full-time grazing system. Data were collected in 10 experimental periods of up to three consecutive days with a moderate comprehensive climate index (CCI). The individual animals' vaginal temperature (VT), heart rate, and locomotor activity data were automatically monitored with sensors. Blood samples and proportional whole milk samples were collected at afternoon milking. The concentrations of beta-hydroxybutyrate, glucose, non-esterified fatty acids, urea nitrogen, plasma thyroxine and triiodothyronine were analysed in blood plasma, and fat, protein, lactose, urea nitrogen, cortisol, Na+, K+, and Cl- concentrations were analysed in milk. The daily distribution of VT recordings greater than 39 °C showed a circadian rhythm with a proportion of recordings of 2% and lower during the night and a percentage of 10% or higher in the afternoon. The cows' maximal daily vaginal temperature (VTMAX) between 0830 and 1430 h was positively related to the mean daily CCI in the same time period (CCIMEAN; mean and SD 23.6 ± 5.4 °C). Cows with greater VTMAX had an increased mean heart rate, plasma glucose and milk cortisol concentrations and decreased concentrations of plasma thyroxine and triiodothyronine. The concentration of Na+ in milk was lower, and the concentration of K+ in milk tended to be higher in cows with increased VTMAX. For beta-hydroxybutyrate, non-esterified fatty acids and urea nitrogen concentrations in plasma and fat and lactose concentrations in milk no relationships were found in terms of increasing VT. For milk urea nitrogen and protein concentrations, the proportion of total variance explained by inter-individual or -period variance was high. In conclusion, changes observed in milk and blood likely reflected short-term physiological responses to moderate heat stress. In particular, milk cortisol and Na+ may be useful traits for timely monitoring of heat stress in individual cows because their inter-individual variances were relatively small and samples can be collected non-invasively.


Assuntos
Lactação , Proteínas do Leite , Feminino , Bovinos , Animais , Lactação/fisiologia , Proteínas do Leite/análise , Tiroxina , Tri-Iodotironina , Ácido 3-Hidroxibutírico , Lactose/metabolismo , Hidrocortisona/metabolismo , Temperatura Alta , Leite/metabolismo , Resposta ao Choque Térmico/fisiologia , Ácidos Graxos não Esterificados , Ureia/metabolismo , Dieta/veterinária
6.
J Dairy Sci ; 103(2): 2024-2039, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31864736

RESUMO

Since heritability of CH4 emissions in ruminants was demonstrated, various attempts to generate large individual animal CH4 data sets have been initiated. Predicting individual CH4 emissions based on equations using milk mid-infrared (MIR) spectra is currently considered promising as a low-cost proxy. However, the CH4 emission predicted by MIR in individuals still has to be confirmed by measurements. In addition, it remains unclear how low CH4 emitting cows differ in intake, digestion, and efficiency from high CH4 emitters. In the current study, putatively low and putatively high CH4 emitting Brown Swiss cows were selected from the entire Swiss herdbook population (176,611 cows), using an MIR-based prediction equation. Eventually, 15 low and 15 high CH4 emitters from 29 different farms were chosen for a respiration chamber (RC) experiment in which all cows were fed the same forage-based diet. Several traits related to intake, digestion, and efficiency were quantified over 8 d, and CH4 emission was measured in 4 open circuit RC. Daily CH4 emissions were also estimated using data from 2 laser CH4 detectors (LMD). The MIR-predicted CH4 production (g/d) was quite constant in low and high emission categories, in individuals across sites (home farm, experimental station), and within equations (first available and refined versions). The variation of the MIR-predicted values was substantially lower using the refined equation. However, the predicted low and high emitting cows (n = 28) did not differ on average in daily CH4 emissions measured either with RC or estimated using LMD, and no correlation was found between CH4 predictions (MIR) and CH4 emissions measured in RC. When individuals were recategorized based on CH4 yield measured in RC, differences between categories of 10 low and 10 high CH4 emitters were about 20%. Low CH4 emitting cows had a higher feed intake, milk yield, and residual feed intake, but they differed only weakly in eating pattern and digesta mean retention times. Low CH4 emitters were characterized by lower acetate and higher propionate proportions of total ruminal volatile fatty acids. We concluded that the current MIR-based CH4 predictions are not accurate enough to be implemented in breeding programs for cows fed forage-based diets. In addition, low CH4 emitting cows have to be characterized in more detail using mechanistic studies to clarify in more detail the properties that explain the functional differences found in comparison with other cows.


Assuntos
Bovinos/fisiologia , Comportamento Alimentar , Metano/análise , Leite/química , Espectrofotometria Infravermelho/veterinária , Animais , Dieta/veterinária , Digestão , Feminino , Lactação , Lasers , Metano/metabolismo , Rúmen/metabolismo
7.
J Dairy Sci ; 102(12): 11751-11765, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587911

RESUMO

Currently, various attempts are being made to implement breeding schemes aimed at producing low methane (CH4) emitting cows. We investigated the persistence of differences in CH4 emission between groups of cows categorized as either low or high emitters over a 5-mo period. Two feeding regimens (pasture vs. indoors) were used. Early- to mid-lactation Holstein Friesian cows were categorized as low or high emitters (n = 10 each) retrospectively, using predictions from milk mid-infrared (MIR) spectra, before the start of the experiment. Data from MIR estimates and from measurements with the GreenFeed (GF; C-Lock Technology Inc., Rapid City, SD) system over the 5-mo experiment were combined into 7-, 14-, and 28-d periods. Feed intake, eating and ruminating behavior, and ruminal fluid traits were determined in two 7-d measurement periods in the grazing season. The CH4 emission data were analyzed using a split-plot ANOVA, and the repeatability of each of the applied methods for determining CH4 emission was calculated. Traits other than CH4 emission were analyzed for differences between low and high emitters using a linear mixed model. The initial category-dependent differences in daily CH4 production persisted over the subsequent 5 mo and across 2 feeding regimens with both methods. The repeatability analysis indicated that the biweekly milk control scheme, and even a monthly scheme as practiced on farms, might be sufficient for confirming category differences. However, the relationship between CH4 data estimated by MIR and measured with GF for individual cows was weak (R2 = 0.26). The categorization based on CH4 production also generated differences in CH4 emission per kilogram of milk; differentiation between cow categories was not persistent based on milk MIR spectra and GF. Compared with the high emitters, low emitters tended to show a lower acetate-to-propionate ratio in ruminal volatile fatty acids, whereas feed intake and ruminating time did not differ. Interestingly, the low emitters spent less time eating than the high emitters. In conclusion, the CH4 estimation from analyzing the milk MIR spectra is an appropriate proxy to form and regularly control categories of cows with different CH4 production levels. The categorization was also sufficient to secure similar and persistent differences in emission intensity when estimated by MIR spectra of the milk. Further studies are needed to determine whether MIR data from individual cows are sufficiently accurate for breeding.


Assuntos
Bovinos/fisiologia , Ácidos Graxos Voláteis/análise , Metano/análise , Leite/química , Animais , Cruzamento , Dieta/veterinária , Comportamento Alimentar , Feminino , Lactação , Metano/metabolismo , Estudos Retrospectivos , Estações do Ano , Espectrofotometria Infravermelho/veterinária
8.
J Dairy Sci ; 102(4): 2985-2999, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30712935

RESUMO

Information about the individual herbage DMI (HDMI) of grazing dairy cows is important for an efficient use of pasture herbage as an animal feed with a range of benefits. Estimating HDMI, with its multifaceted influencing variables, is difficult but may be attempted using animal, performance, behavior, and feed variables. In our study, 2 types of approaches were explored: 1 for HDMI estimation under a global approach (GA), where all variables measured in the 4 underlying experiments were used for model development, and 1 for HDMI estimation in an approach without information about the amount of supplements fed in the barn (WSB). The accuracy of these models was assessed. The underlying data set was developed from 4 experiments with 52 GA and 50 WSB variables and one hundred thirty 7-d measurements. The experiments differed in pasture size, herbage allowance, pregrazing herbage mass, supplements fed in the barn, and sward composition. In all the experiments, cow behavioral characteristics were recorded using the RumiWatch system (Itin and Hoch GmbH, Liestal, Switzerland). Herbage intake was estimated by applying the n-alkane method. Finally, HDMI estimation models with a minimal relative prediction error of 11.1% for use under GA and 13.2% for use under WSB were developed. The variables retained for the GA model with the highest accuracy, determined through various selection steps, were herbage crude protein, chopped whole-plant corn silage intake in the barn, protein supplement or concentrate intake in the barn, body weight, milk yield, milk protein, milk lactose, lactation number, postgrazing herbage mass, and bite rate performed at pasture. Instead of the omitted amounts of feed intake in the barn and, due to the statistical procedure for model reduction, the unconsidered variables postgrazing herbage mass and bite rate performed at pasture, the WSB model with the highest accuracy retained additional variables. The additional variables were total eating chews performed at pasture and in the barn, total eating time performed at pasture, number of total prehension bites, number of prehension bites performed at pasture, and herbage ash concentration. Even though behavioral characteristics alone did not allow a sufficiently accurate individual HDMI estimation, their inclusion under WSB improved estimation accuracy and represented the most valid variables for the HDMI estimation under WSB. Under GA, the inclusion of behavioral characteristics in the HDMI estimation models did not reduce the root mean squared prediction error. Finally, further adaptation, as well as validation on a more comprehensive data set and the inclusion of variables excluded in this study such as body condition score or gestation, should be considered in the development of HDMI estimation models.


Assuntos
Ração Animal , Bovinos/fisiologia , Dieta/veterinária , Animais , Comportamento Animal , Peso Corporal , Indústria de Laticínios , Suplementos Nutricionais , Ingestão de Alimentos , Meio Ambiente , Feminino , Herbivoria , Lactação , Lactose/análise , Leite/química , Proteínas do Leite , Silagem , Suíça , Zea mays
9.
J Dairy Sci ; 101(3): 2463-2475, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29290426

RESUMO

Observation of ingestive and rumination behaviors of dairy cows may assist in detecting diseases, controlling reproductive status, and estimating intake. However, direct observation of cows on pasture is time consuming and can be difficult to realize. Consequently, different systems have been developed to automatically record behavioral characteristics; among them is the RumiWatch System (RWS; Itin and Hoch GmbH, Liestal, Switzerland). Until now, the RWS has not been thoroughly validated under grazing conditions. The aim of the current study was to validate the RWS, against direct observation, in measuring ingestive and rumination behaviors of dairy cows during grazing and supplementation in the barn. A further objective was to examine whether it is possible to refine the algorithm used by the evaluation software RumiWatch Converter 0.7.3.2 to improve the accuracy of the RWS. The data were collected from an experiment carried out with 18 lactating Holstein cows in a crossover block design including 3 treatments and 3 measuring periods. All cows grazed night and day, 19 h/d, and were either unsupplemented or supplemented, with chopped whole-plant corn silage, or chopped whole-plant corn silage mixed with a protein concentrate. During the measuring periods, cows were equipped with the RumiWatch Halter, and their ingestive and rumination behaviors were recorded concurrently by the RumiWatch Halter and by direct observation (690 × 10 min). Comparison of concurrently measured data shows that the RWS detected jaw movements reliably, but classification errors occurred. A low relative prediction error of ≤0.10 for the number of rumination boluses, rumination chews, and total eating chews was found. A high relative prediction error of >0.10 was found for the number of prehension bites and time spent in prehension and eating. Both converter versions performed equally well in differentiating ingestive and rumination behaviors when cows were supplemented in the barn or when grazing and supplementation activities were combined. For grazing cows, with no supplementation, more reliable results for the total number of eating chews, rumination chews, prehension bites, and time spent in these activities were obtained, by using the RumiWatch Converter 0.7.3.11. In light of these findings, further research is warranted to improve the accuracy of the RWS and to allow a differentiation between mastication chews and prehension bites while eating.


Assuntos
Bovinos/fisiologia , Comportamento Alimentar , Arcada Osseodentária/fisiologia , Mastigação , Ração Animal , Animais , Suplementos Nutricionais , Ingestão de Alimentos/fisiologia , Feminino , Lactação , Silagem/análise , Suíça , Zea mays
10.
J Anim Physiol Anim Nutr (Berl) ; 101(4): 767-778, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26959798

RESUMO

Herbage feeding with only little input of concentrates plays an important role in milk production in grassland dominated countries like Switzerland. The objective was to investigate the effects of a solely herbage-based diet and level of milk production on performance, and variables related to the metabolic, endocrine and inflammatory status to estimate the stress imposed on dairy cows. Twenty-five multiparous Holstein cows were divided into a control (C+, n = 13) and a treatment group (C-, n = 12), according to their previous lactation yield (4679-10 808 kg) from week 3 ante partum until week 8 post-partum (p.p.). While C+ received fresh herbage plus additional concentrate, no concentrate was fed to C- throughout the experiment. Within C+ and C-, the median of the preceding lactation yields (7752 kg) was used to split cows into a high (HYC+, HYC-)- and low-yielding (LYC+, LYC-) groups. Throughout the study, HYC+ had a higher milk yield (35.9 kg/d) compared to the other subgroups (27.2-31.7 kg/d, p < 0.05). Plasma glucose (3.51 vs. 3.72 mmol/l) and IGF-1 (66.0 vs. 78.9ng/mL) concentrations were lower in HYC-/LYC- compared to HYC+/LYC+ cows (p < 0.05). Plasma FFA and BHBA concentrations were dramatically elevated in HYC- (1.1 and 1.6 mmol/l) compared to all other subgroups (mean values: 0.5 and 0.6 mmol/l, p < 0.05). Saliva cortisol, plasma concentrations of serum amyloid A (SAA), haptoglobin (Hp), beta-endorphin (BE) and activity of alkaline phosphatase (AP) were not different between C+ and C-. In conclusion, herbage-fed high-yielding cows without supplementary concentrate experienced a high metabolic load resulting in a reduced performance compared to cows of similar potential fed accordingly. Low-yielding cows performed well without concentrate supplementation. Interestingly, the selected markers for inflammation and stress such as cortisol, Hp, SAA, BE and AP gave no indication for the metabolic load being translated into compromised well-being.


Assuntos
Ração Animal/análise , Doenças dos Bovinos/sangue , Bovinos/fisiologia , Dieta/veterinária , Metabolismo Energético/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Biomarcadores/sangue , Biomarcadores/química , Peso Corporal , Bovinos/sangue , Doenças dos Bovinos/diagnóstico , Leite/química , Saliva/química
11.
J Dairy Sci ; 99(3): 1951-1955, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26723129

RESUMO

Subacute ruminal acidosis is one of the most important digestive disorders in high-yielding dairy cows fed highly fermentable diets. Monitoring of forestomach pH has been suggested as a potentially valuable tool for diagnosing subacute ruminal acidosis. The objective of the present study was to compare continuously recorded measurements of an indwelling telemetric pH sensor inserted orally in the reticulum with those obtained from a measurement system placed in the ventral sac of the rumen through a cannula. The experiment was conducted with 6 ruminally cannulated Holstein cows kept in a freestall barn. Equal numbers of cows were assigned to 2 treatment groups based on their previous lactation milk yield. Cows in treatment CON- were offered a diet consisting of only fresh herbage cut once daily, and cows in treatment CON+ got fresh herbage plus a concentrate supplement according to the individual milk yield of each cow to meet their predicted nutrient requirements. The experiment lasted from 2 wk before the predicted calving date until wk 8 of lactation. During the whole experiment, a pH value was recorded every 10 min in the reticulum using a wireless telemetry bolus including a pH sensor (eBolus, eCow Ltd., Exeter, Devon, UK), which had been applied orally using a balling gun. Simultaneously, in wk 2, before the estimated calving date and in wk 2, 4, 6, and 8 of lactation, the ruminal pH was measured every 30 s for 48 h with the LRCpH measurement system (Dascor Inc., Escondido, CA) placed in the ventral sac of the rumen through the cannula. The readings of the LRCpH measurement system were summarized as an average over 10 min for statistical analysis. The recorded pH values were on average 0.24 pH units higher in the reticulum than in the rumen. The reticular pH also showed less fluctuation (overall SD 0.19 pH units) than pH profiles recorded in the rumen (overall SD 0.51 pH units). Regardless of measurement system, pH was not influenced by treatment, but varied across week of lactation and decreased with advancing lactation. The difference between ruminal and reticular pH varied across week of lactation. Due to this variation, no fixed conversion factor can be provided to make pH measurements in the reticulum comparable with those in the rumen.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Retículo/química , Rúmen/química , Animais , Indústria de Laticínios/instrumentação , Dieta/veterinária , Feminino , Concentração de Íons de Hidrogênio , Lactação
12.
Epidemiol Infect ; 142(8): 1625-35, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24112364

RESUMO

Two community-based density case-control studies were performed to assess risk factors for cholera transmission during inter-peak periods of the ongoing epidemic in two Haitian urban settings, Gonaives and Carrefour. The strongest associations were: close contact with cholera patients (sharing latrines, visiting cholera patients, helping someone with diarrhoea), eating food from street vendors and washing dishes with untreated water. Protective factors were: drinking chlorinated water, receiving prevention messages via television, church or training sessions, and high household socioeconomic level. These findings suggest that, in addition to contaminated water, factors related to direct and indirect inter-human contact play an important role in cholera transmission during inter-peak periods. In order to reduce cholera transmission in Haiti intensive preventive measures such as hygiene promotion and awareness campaigns should be implemented during inter-peak lulls, when prevention activities are typically scaled back.


Assuntos
Cólera/epidemiologia , Cólera/transmissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Haiti/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
13.
Diabet Med ; 29(7): e96-101, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22435673

RESUMO

AIMS: Smoking is a major risk factor for cardiovascular complications among patients with diabetes. Hospitalization has been shown to enhance cessation rates. The purpose of this study was to compare 6-month post-hospitalization tobacco cessation rates among US veterans with and without diabetes. METHODS: This was a longitudinal study among inpatient veterans who used tobacco in the past month (n = 496). Patients were recruited and surveyed from three Midwestern Department of Veterans Affairs hospitals during an acute-care hospitalization. They were also asked to complete a follow-up survey 6 months post-discharge. Bivariate- and multivariable-adjusted analyses were conducted to determine differences in tobacco cessation rates between patients with and without a diagnosis of diabetes. RESULTS: The mean age of patients was 55.2 years and 62% were white. Twenty-nine per cent had co-morbid diabetes. A total of 18.8% of patients with diabetes reported tobacco cessation at 6 months compared with 10.9% of those without diabetes (P = 0.02). Cotinine-verified cessation rates were 12.5 vs. 7.4% in the groups with and without diabetes, respectively (P = 0.07). Controlling for psychiatric co-morbidities, depressive symptoms, age, self-rated health and nicotine dependence, the multivariable-adjusted logistic regression showed that patients with diabetes had three times higher odds of 6-month cotinine-verified tobacco cessation as compared with those without diabetes (odds ratio 3.17, P = 0.005). CONCLUSIONS: Post-hospitalization rates of smoking cessation are high among those with diabetes. Intensive tobacco cessation programmes may increase these cessation rates further.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/epidemiologia , Transtornos Mentais/epidemiologia , Abandono do Uso de Tabaco/estatística & dados numéricos , Doenças Cardiovasculares/prevenção & controle , Comorbidade , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Pacientes Internados , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos , Prevalência , Fatores de Risco , Inquéritos e Questionários , Estados Unidos/epidemiologia , Veteranos/estatística & dados numéricos
14.
J Anim Physiol Anim Nutr (Berl) ; 96(2): 228-36, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21453349

RESUMO

Grass may have a differential impact on the metabolism of the dairy cow, depending on the grazing system applied. In this study, the hypothesis was tested that metabolism of grazed vs. zero-grazed dairy cows is differently regulated throughout the vegetation period. The study included three experimental periods (p1, p2 and p3) of 14 days each, and two treatments [grazing from pasture, PASTURE, n = 9; or zero-grazing in a free-stall barn (BARN, n = 9)]. Blood and liver samples were collected at the end of each period when the cows were on average 64, 120 and 197 DIM. Concentrations of metabolites and hormones, and activities of various enzymes were determined in plasma. Liver samples were measured for mRNA abundance of genes encoding enzymes and nuclear receptors involved in metabolic pathways. PASTURE cows had higher plasma concentrations of T(3), BHB, and total protein than BARN cows across periods (p < 0.05). BARN cows had higher concentrations of NEFA (in p1) and urea (in p1 and p2) in relation PASTURE cows (p < 0.05), and had higher mRNA abundance of liver-X-receptor-α and glycerol-3-phosphate-acyltransferase across periods (p < 0.05). The results confirm the hypothesis that metabolism is different between BARN and PASTURE cows throughout the vegetation period, and show that the observed differences are mainly reflected in parameters of lipid metabolism.


Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Bovinos/sangue , Bovinos/fisiologia , Fígado/metabolismo , Estações do Ano , Fenômenos Fisiológicos da Nutrição Animal , Animais , Metabolismo dos Carboidratos/fisiologia , Indústria de Laticínios , Dieta/veterinária , Metabolismo Energético/fisiologia
15.
J Dairy Sci ; 94(4): 1989-2000, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21426990

RESUMO

The objectives of the study were to assess the 13C bicarbonate dilution technique using an automatic blood sampling system and to use this technique to estimate energy expenditure (EE) based on the CO2 production of 14 lactating Holstein cows on pasture or in a freestall barn. The effects of physical activity and eating behavior on EE were also assessed. Cows were exposed to each feeding system in a crossover design with two 14-d experimental periods, each consisting of an adaptation period and a 7-d data collection period. Cows either grazed on pasture or had ad libitum access, in the freestall barn, to grass cut daily from the same paddock. All cows were supplemented with a cereal-based concentrate. The EE of each cow was determined from 0700 to 1300 h on 1 d of each collection period. Blood samples for the 13C bicarbonate dilution technique were taken either manually in the barn or using an automatic blood sampling system on pasture. Eating pattern and physical activity were recorded from 0700 to 1300 h using a behavior recorder and an activity meter, respectively. Milk yield was recorded daily. Individual feed intake was estimated using the alkane double-indicator technique. Two preceding experiments confirmed that the sampling technique (manual or automatic) and the following storage of the blood samples (frozen directly after withdrawal or first cooled on ice and then frozen 6 h later) had no effect on 13CO2 enrichment in the extracted blood CO2 or on the subsequent calculation of CO2 production. During the 6-h measurement period, the EE of cows on pasture was higher than that of cows in the freestall barn. Daily feed intake and milk production were not affected by the feeding treatment. Grazing cows spent more time walking and less time standing and lying than did cows fed indoors. Time spent eating was greater and time spent ruminating was lower for cows on pasture compared with grass-fed cows in the barn. In conclusion, the 13C bicarbonate dilution technique, combined with an automatic blood sampling system, is a suitable method to determine the EE of lactating dairy cows on pasture. Positive correlations between EE and walking and eating time indicate that the higher energy requirements of dairy cows on pasture may be at least partly caused by a higher level of physical activity. However, before specific recommendations about additional energy supply can be given, it must be determined whether EE measured over 6 h can be extrapolated to 24 h. Furthermore, the apparent inconsistency between EE, feed intake, and milk production needs to be resolved.


Assuntos
Coleta de Amostras Sanguíneas/veterinária , Bovinos/fisiologia , Indústria de Laticínios/métodos , Metabolismo Energético/fisiologia , Métodos de Alimentação/veterinária , Poaceae/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Automação , Coleta de Amostras Sanguíneas/instrumentação , Coleta de Amostras Sanguíneas/métodos , Dióxido de Carbono/sangue , Bovinos/sangue , Bovinos/metabolismo , Estudos Cross-Over , Comportamento Alimentar/fisiologia , Feminino , Lactação/fisiologia , Atividade Motora/fisiologia
16.
J Anim Physiol Anim Nutr (Berl) ; 95(6): 717-29, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21114551

RESUMO

This study compared productivity of dairy cows with different body weight (BW), but a constant ratio of maintenance to production requirements in their first lactation, in a pasture-based production system with spring calving. Two herds, Herd L (13 and 14 large cows in 2003 and 2004 respectively; average BW after calving, 721 kg) and Herd S (16 small cows in both years; 606 kg) [Correction added after online publication 14 January 2011: 16 small cows in both years; 621 kg was changed to 16 small cows in both years; 606 kg], all in their second or following lactations, were each allocated 6 ha of pasture and rotationally grazed on 10 parallel paddocks with equal herbage offer and nutritional values. Winter hay, harvested from the same pastures, was offered ad libitum in the indoor periods in a tied stall barn. Each herd received, per lactation and year, approximately 2000 kg dry matter (DM) of concentrates and of fodder beets, equally distributed to every individual. Indoors, the L-cows ingested more DM than the S-cows (18.7 vs. 16.3 kg DM/cow per day; p < 0.01), but DM intake per 100 kg of metabolic BW was similar (13.0 vs. 13.1 kg DM/cow per day). Estimates based on the n-alkane technique gave similar results on pasture (17.9 vs. 15.5 kg DM/cow per day; p < 0.001). Roughage intakes per 100 kg of metabolic BW, at 13.5 kg DM/cow per day, were similar. Mean annual yield of energy-corrected milk (ECM)/ha was slightly higher for the S-herd than the L-herd (13,026 vs. 12,284 kg) but was associated with a higher stocking rate (on average +20%) for the S-herd. Feed conversion efficiency (1.2 vs. 1.3 kg ECM/kg DM intake) and overall milk production efficiency (45.3 vs. 47.3 kg ECM/kg metabolic BW) were similar in L- and S-cows. Thus, both dairy cow types were equally efficient in utilising pasture-based forage.


Assuntos
Criação de Animais Domésticos/métodos , Peso Corporal/fisiologia , Bovinos/fisiologia , Lactação/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Fertilidade , Estações do Ano , Tempo
17.
Arch Orthop Trauma Surg ; 120(5-6): 326-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10853905

RESUMO

We measured radiographically the interspinous distance in 50 normal children and in 50 children with congenital dislocation of the hip. The value increased proportionally with age in normal children, but not in those with congenital dislocation of the hip. Our results indicate that a bony parameter, rather than the age of the child, is suitable for the indication of lower age limit for Salter's innominate osteotomy.


Assuntos
Antropometria , Luxação Congênita de Quadril/diagnóstico por imagem , Fatores Etários , Criança , Pré-Escolar , Feminino , Luxação Congênita de Quadril/cirurgia , Humanos , Lactente , Variações Dependentes do Observador , Pelve/diagnóstico por imagem , Radiografia , Valores de Referência
18.
J Vet Med A Physiol Pathol Clin Med ; 47(1): 43-60, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10841462

RESUMO

Effects of feeding crystalline triglycerides (TGA), free fatty acids (FFA), and a starch-rich ration (STA) on metabolite and hormone concentrations in blood plasma were studied in high-yielding dairy cows over a 24-h period in week 9 and 19 of lactating. Energy-corrected milk production in the three groups was similar, but was lower in week 19 than in week 9. Energy and protein intakes were greater in week 9 than in week 19, but energy and protein balances in the three groups and in weeks 9 and 19 were similar. Plasma glucose and triglyceride concentrations were lower in week 9 than in week 19. In cows fed FFA, glucose concentrations were highest in week 9. Plasma triglyceride, phospholipid and cholesterol concentrations were highest, whereas beta-hydroxybutyrate concentrations were lowest in FFA-fed cows in weeks 9 and 19. Concentrations of insulin-like growth factor-I in week 19 were lower in cows fed TGA and FFA than in those fed the starch-rich ration. Post-prandial responses were usually greater following morning than afternoon meals. Fructosamine, albumin, urea, growth hormone, thyroxine, and 3,5,3'-triiodothyronine concentrations were similar in weeks 9 and 19 and were not influenced by dietary treatment or feeding times. In conclusion, there were distinct metabolic and endocrine effects of feeding TGA and FFA compared with STA and the concentrations as well as the 24-h changes of various metabolic and endocrine traits in weeks 9 and 19 of lactation were also different.


Assuntos
Bovinos/metabolismo , Ritmo Circadiano/fisiologia , Ácidos Graxos/metabolismo , Lactação/metabolismo , Triglicerídeos/metabolismo , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/análise , Metabolismo dos Carboidratos , Carboidratos/fisiologia , Bovinos/fisiologia , Colesterol/sangue , Ácidos Graxos/administração & dosagem , Ácidos Graxos/sangue , Feminino , Frutosamina/sangue , Hormônio do Crescimento Humano/sangue , Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Lactação/fisiologia , Leite/metabolismo , Fosfolipídeos/sangue , Prolactina/sangue , Albumina Sérica/análise , Tironinas/sangue , Triglicerídeos/administração & dosagem , Triglicerídeos/sangue , Tri-Iodotironina/sangue , Ureia/sangue
19.
Cell Tissue Res ; 225(1): 217-22, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6288249

RESUMO

The effects of acute injections of synthetic opiate peptides into the lateral cerebral ventricle of young adult male rats on cells of the intermediate lobe of the pituitary were studied. Met-enkephalin (100/micrograms) injected into anesthetized rats, or 20 micrograms beta-endorphin administered via a previously implanted cannula to unanesthetized animals, will lead to cell degranulation and often to expanded Golgi zones and prominent regions of rough endoplasmic reticulum in secretory cells when tissue is fixed 45--60 min after peptide administration. Treatment of animals with the opiate antagonist naloxone hydrochloride prior to enkephalin injection appeared to prevent the cellular changes elicited with peptide alone. Observations suggest that opiate peptides administered to the cerebrospinal fluid may stimulate release of pro-opiomelanocortin-peptide from pituitary cells.


Assuntos
Endorfinas/farmacologia , Encefalina Metionina/farmacologia , Hipófise/citologia , Hormônios Adeno-Hipofisários/fisiologia , Precursores de Proteínas/fisiologia , Animais , Grânulos Citoplasmáticos/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/ultraestrutura , Masculino , Naloxona/farmacologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Pró-Opiomelanocortina , Ratos , Ratos Endogâmicos , beta-Endorfina
20.
Brain Res Bull ; 6(6): 517-24, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7248815

RESUMO

Administration of single or multiple 10 mg/kg doses of parachloroamphetamine hydrochloride, a serotonin-neurotoxic drug, to adult male rats, leads to emergence of clusters of supraependymal cells in the third ventricle above the median eminence. Transmission EM of specimens previously examined with scanning electron optics reveals that the cell clusters have characteristics of neurons. Two weeks after the initial drug injection, the ventricular surfaces of some animals lack the cell clusters, suggesting a "transience" in their appearance. The neuron-like elements may appear in response to alterations in brain serotonin levels, and their presence suggests an ability of adult nerve cells to migrate in response to chemical changes in neural tissue or cerebrospinal fluid.


Assuntos
Anfetaminas/farmacologia , Epêndima/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , p-Cloroanfetamina/farmacologia , Animais , Relação Dose-Resposta a Droga , Masculino , Eminência Mediana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Fibras Nervosas/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Ratos
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