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1.
Braz J Biol ; 82: e264210, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36350939

RESUMEN

Fishing plays a prominent role in the socioeconomic scope of the Negro River basin and is considered one of the main extractive activities in the region. The objective of this study was to describe the socioeconomic aspects of commercial fishers of edible fish who work in the municipality of Barcelos, in the middle Negro River region, as well as to highlight the scenario of the fishing activity from the point of view of the fishers. The information was collected between January and December 2016 in the municipality of Barcelos, state of Amazonas, via semi-structured questionnaires. Most interviewees were male (71.14%), aged between 18 and 82 years and a mean age of 48 years. With a low level of education, 45.0% had only incomplete elementary education and 15% were illiterate. The fishing tackle most used by fishermen was the gillnet, especially by urban fishermen (70%). Among the fishing sites, the main one was the Demeni River (50%). Commercial fishing for edible fish in Barcelos focused on Characiformes, Perciformes and Siluriformes fish. The main difficulties faced by the activity are related to the seasonality of the level of rivers and local tributaries, as well as the lack of buyers and low selling price of fish, in addition to conflicts over the use of fishing resources. Commercial fishing for edible fish is an activity of great socioeconomic importance for riverside families in the Middle River Negro basin, which needs greater attention from the public authorities. Therefore, it is expected that the information contained in this study can help in the decision-making process for the management of local fisheries resources and contribute to the resumption of growth and sustainability of commercial edible fish fisheries.


Asunto(s)
Conservación de los Recursos Naturales , Ríos , Humanos , Animales , Masculino , Femenino , Brasil , Negro o Afroamericano , Caza , Explotaciones Pesqueras , Factores Socioeconómicos , Peces
2.
Meat Sci ; 179: 108492, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33771427

RESUMEN

The percentage of intramuscular fat content of lamb meat is a key index of consumer acceptability. Hyperspectral imaging is a potential technique for in-line measurements of intramuscular fat in fresh meat. However, little work has been conducted to investigate the robustness of hyperspectral imaging data and associated multivariate models over time. Fifteen trials consisting of eight independent flocks across five years were used to quantify robustness of partial least squares regression (PLSR) models developed using data collected with the same imaging system. Two models were developed; one using data from the first year of the trials, and a progressive model that cumulatively includes data in chronological order. The two models performed similarly, in terms of the coefficient of determination (R2), standard error of prediction (SEP) and bias, when experimental conditions were consistent. However, under varying imaging conditions, the progressive model was able to account for this variability resulting in higher R2 and lower SEP.


Asunto(s)
Imágenes Hiperespectrales/veterinaria , Carne Roja/análisis , Tejido Adiposo , Animales , Imágenes Hiperespectrales/métodos , Análisis de los Mínimos Cuadrados , Músculo Esquelético/anatomía & histología , Ovinos
3.
Meat Sci ; 181: 108405, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33451871

RESUMEN

This study demonstrates a novel approach to develop global calibration models for predicting intramuscular fat (IMF) and pH across various red meat species and muscle types. A total of 8 hyperspectral imaging (HSI) datasets were used from different experiments, comprising data from three species: beef, lamb and venison across various muscle type, slaughter season and measurement conditions. Prediction models were developed using Partial Least Squares Regression (PLSR) and Deep Convolutional Neural Networks (DCNN) using a total of 1080 and 1116 samples for IMF and pH, respectively. Models for pH and IMF via both techniques yielded high Rc2 (0.86-0.93) and low SEC values. Also, reasonably accurate prediction performance was observed with high Rp2 (0.86-0.89) and low SEP values. Overall results illustrated the comprehensiveness of these global calibration models with the ability to predict IMF and pH of red meat samples irrespective of species and muscle type.


Asunto(s)
Tejido Adiposo , Imágenes Hiperespectrales/veterinaria , Carne Roja/análisis , Animales , Calibración , Bovinos , Ciervos , Concentración de Iones de Hidrógeno , Imágenes Hiperespectrales/métodos , Análisis de los Mínimos Cuadrados , Redes Neurales de la Computación , Ovinos
4.
Meat Sci ; 181: 108376, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33423830

RESUMEN

This study investigates the performance of a partial least squares regression model to predict intramuscular fat (IMF) in lamb M. longissimus lumborum developed using near infrared (NIR) data collected under a range of different conditions. A total of 26 independent NIR datasets were collected across 7 years, including 14 flocks, four devices and several measurement conditions. A model is developed and its performance is tested using a total of n = 3201 NIR spectra and intramuscular fat percentage measurements by wet chemistry. The model had a coefficient of determination by cross-validation of 0.52, which agrees with previous results using smaller numbers of animals. Overall the results show that near infrared models can be robust across many varying conditions. These models could potentially be implemented in an automated meat quality monitoring system.


Asunto(s)
Tejido Adiposo , Carne Roja/análisis , Espectroscopía Infrarroja Corta/veterinaria , Animales , Análisis de los Mínimos Cuadrados , Músculo Esquelético , Nueva Zelanda , Oveja Doméstica , Espectroscopía Infrarroja Corta/métodos
5.
Meat Sci ; 181: 108410, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33358222

RESUMEN

This study evaluated a range of diffuse reflectance spectroscopic (Vis-NIR spectrophotometers) and imaging (Hyperspectral imaging cameras) instruments for predicting pH, IMF and shear force values of beef in a meat processing pilot plant. A total of 364 beef striploin samples were evaluated and prediction models were developed using PLSR. Models for pH and IMF (except Vis snapshot camera) showed good fit with high Rcv2 (0.29-0.92) and low SECV values. Good prediction accuracy with high Rp2 (0.44-0.90), RPD and low SEP values was also observed. While low values of Rp2 for shear force was observed, the expected curvilinear relationship between predicted values of shear force and predicted values of pH was observed suggesting that spectroscopic measurements were able detect biophysical factors associated to these two attributes. Overall, it can be concluded that diffuse reflectance spectroscopy combined with chemometrics has a great potential to be used as an on/in-line quality monitoring system for the meat processing industry.


Asunto(s)
Imágenes Hiperespectrales/veterinaria , Carne Roja/análisis , Espectroscopía Infrarroja Corta/veterinaria , Tejido Adiposo , Animales , Bovinos , Femenino , Manipulación de Alimentos , Calidad de los Alimentos , Concentración de Iones de Hidrógeno , Imágenes Hiperespectrales/métodos , Masculino , Músculo Esquelético , Resistencia al Corte , Espectroscopía Infrarroja Corta/métodos
6.
Meat Sci ; 162: 108026, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31816518

RESUMEN

This study compares a miniaturized spectrophotometer to benchtop and hand-held Vis-NIR instruments in the spectral range of 900-1700 nm for prediction of intramuscular fat (IMF) content of freeze-dried ground lamb meat; and their ability to differentiate fresh lamb meat based on animal age (4 vs 12 months). The performance of the miniaturized spectrophotometer was not affected by sample temperature equilibration time. Partial Least Square regression models for IMF showed Rcv2 = 0.86-0.89 and RMSECV = 0.36-0.40 values for all instruments. Day-to-day instrumental variation adversely affected performance of the miniaturized spectrophotometer (R2p = 0.27, RMSEP = 1.28). This negative effect was overcome by representing day-to-day variation in the model. The benchtop spectrophotometer and miniaturized spectrophotometer differentiated lamb meat by animal age. The miniaturized spectrophotometer has potential to be a fast, ultra-compact and cost-effective device for predicting IMF in freeze-dried ground lamb meat and for age classification of fresh lamb meat.


Asunto(s)
Tejido Adiposo , Productos de la Carne/análisis , Carne Roja/análisis , Espectrofotometría/métodos , Factores de Edad , Animales , Femenino , Liofilización , Masculino , Ovinos , Espectrofotometría/instrumentación , Espectroscopía Infrarroja Corta/instrumentación , Espectroscopía Infrarroja Corta/métodos
7.
Meat Sci ; 132: 19-28, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28551294

RESUMEN

Cost-effective, rapid and objective measurement of lamb quality on a routine basis is an important step for lamb value chains wishing to manage lamb product quality. Hyperspectral imaging (HSI) technology has shown promise as a solution for objective non-invasive prediction of meat quality. The performance of HSI applied 24h post mortem to lamb M. longissimus lumborum (LL) within a processing plant environment was assessed over two sampling years to evaluate its suitability for an objective lamb meat quality assurance tool. Calibration and validation steps were undertaken to evaluate HSI prediction performance for predicting fatty acid content and composition (n=1020 lambs) and pH (n=2406 lambs). Practical considerations of reference meat quality data quality and validation strategies are discussed. HSI can be used to predict meat quality parameters of lamb LL with varying accuracy levels, but ongoing calibration and validation across seasons is required to improve robustness of HSI for objective non-invasive assessment of lamb meat quality.


Asunto(s)
Ácidos Grasos/análisis , Músculos Paraespinales/química , Carne Roja/análisis , Análisis Espectral/métodos , Animales , Calidad de los Alimentos , Concentración de Iones de Hidrógeno , Ovinos
8.
Animal ; 9(9): 1500-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25990965

RESUMEN

This experiment compared growth, physiological, and reproductive responses of beef heifers with (MI) or without (CON) access to a creep-feeder, as a manner to stimulate metabolic imprinting while nursing their dams. On day 0, 60 Angus × Hereford heifers were ranked by BW and age (140 ± 3 kg and 68±3 days), and assigned to pairs so all ranking criteria were similar between heifers within each pair. On day 1, pairs were randomly assigned to MI (n=15) or CON (n=15). From day 1 to 51, MI pairs and their dams were allocated to 15 drylot pens where heifers had ad libitum access to a corn-based supplement through a creep-feeder. The CON pairs and their dams were maintained in an adjacent single drylot pen. From day 52 to 111, treatments were managed as a single group on a semiarid range pasture. On day 111, heifers were weaned and allocated to two pastures (one pasture/treatment), receiving hay and a corn-based concentrate until day 326. Heifer BW was recorded before and at the end of the creep-feeding period (day 1 to 51), and on days 112 and 326. On days 0, 51, 111, 187, 261, and 325, jugular blood was collected and real-time ultrasonography for longissimus muscle depth and backfat thickness assessment was performed. Blood was also collected every 10 days from days 113 to 323 for puberty evaluation via plasma progesterone. Liver and subcutaneous fat biopsies were performed on days 51, 111, 261 and 325. Average daily gain was greater (P<0.01) for MI than CON from day 1 to 51, tended (P=0.09) to be greater for CON than MI from day 112 to 326, while BW on day 326 was similar between treatments. On day 51, MI had greater (P ⩽ 0.01) plasma IGF-I and glucose concentrations, as well as mRNA expression of hepatic pyruvate carboxylase and adipose fatty acid synthase than CON. On days 261 and 325, plasma insulin concentrations were greater (P ⩽ 0.03) in CON than MI. Mean mRNA expression of hepatic IGF-I and adipose peroxisome proliferator-activated receptor gamma were greater (P ⩽ 0.05) in MI than CON. No treatment effects were detected for puberty attainment rate. In conclusion, supplementing nursing heifers via creep-feeding for 50 days altered physiological and biochemical variables suggestive of a metabolic imprinting effect, but did not hasten their puberty attainment.


Asunto(s)
Bovinos/fisiología , Conducta Alimentaria/fisiología , Métodos de Alimentación/veterinaria , Impronta Psicológica/fisiología , Reproducción/fisiología , Maduración Sexual/fisiología , Tejido Adiposo/metabolismo , Factores de Edad , Animales , Glucemia/metabolismo , Composición Corporal/fisiología , Suplementos Dietéticos , Métodos de Alimentación/instrumentación , Femenino , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , PPAR gamma/metabolismo , Músculos Paraespinales/diagnóstico por imagen , Progesterona/sangre , Ultrasonografía , Zea mays/metabolismo
9.
Theriogenology ; 84(2): 312-20, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25917883

RESUMEN

Holstein heifers (n = 57) were monitored using accelerometers and video observations with the objective of better understanding the behavioral expression of estrus, the variation within and between the heifers, and the possible sources of variation. IceTags recorded walking activity from 7 to 13 months of age. Activity peaks (n = 282) were obtained from a rolling sum of steps within 24-hour periods and validated to be estrus by ovarian ultrasonography. Behavior around activity peak of one estrus for each of 12 heifers was described in detail from video recordings. Baseline behavior was monitored in a corresponding interval 1 week before. Estrus and baseline total steps and steps per hour, estrus relative increase in activity, duration, and interval between episodes were analyzed by descriptive statistics and Spearman rank correlations. Effects of category of baseline walking activity, estrus order (pubertal vs. second and greater episodes), season, hour of estrus onset, and number of heifers simultaneously in estrus were evaluated with proc MIXED. Behavioral changes from baseline to estrus were evaluated by a signed-rank test. Estrus total steps varied greatly (4743 ± 1740; range: 837-10,070), as well as the relative increase in activity (290 ± 160%; range: 30%-1190%). Duration of estrus was 14 ± 4 hours, ranging from 4 to 26 hours. The interval between episodes was the trait that varied the least. Pubertal estrus was shorter and had a smaller relative increase in activity than second and greater episodes (P < 0.05). The number of steps during estrus was greater for heifers of high baseline activity (P < 0.01). Estrus episodes occurring in the winter and starting between 4 PM and 3 AM had the greatest relative increase in activity (P < 0.05). The number of heifers simultaneously in estrus did not influence estrus expression (P > 0.05). The behaviors with greatest change from baseline to estrus were chin rest, sniff, back mount, crossover, accept chin rest, and follow, but variation was large. Overall, estrus was apparent in behavioral changes with large variation within and between the heifers. Estrus order, onset hour, season, and baseline walking activity are important factors affecting estrus activity. Therefore, estrus detection tools should account for potential sources of variation. The visual and automated measurements of estrus expression reported in this study reveal possibilities for improved on-farm estrus detection technologies and potential genetic selection for estrus expression.


Asunto(s)
Conducta Animal/fisiología , Bovinos/fisiología , Estro/fisiología , Caminata/fisiología , Acelerometría/instrumentación , Acelerometría/veterinaria , Animales , Detección del Estro/métodos , Femenino , Estaciones del Año , Maduración Sexual/fisiología , Grabación en Video
10.
J Anim Sci ; 93(1): 386-94, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25412746

RESUMEN

The objective of this experiment was to determine if frequency of protein supplementation impacts physiological responses associated with reproduction in beef cows. Fourteen nonpregnant, nonlactating beef cows were ranked by age and BW and allocated to 3 groups. Groups were assigned to a 3 × 3 Latin square design, containing 3 periods of 21 d and the following treatments: 1) soybean meal supplementation daily (D), 2) soybean meal supplementation 3 times/week (3WK), and 3) soybean meal supplementation once/week (1WK). Within each period, cows were assigned to an estrus synchronization protocol: 100 µg of GnRH + controlled internal drug release device (CIDR) containing 1.38 g of progesterone (P4) on d 1, 25 mg of PGF2α on d 8, and CIDR removal + 100 µg of GnRH on d 11. Grass-seed straw was offered for ad libitum consumption. Soybean meal was individually supplemented at a daily rate of 1 kg/cow (as-fed basis). Moreover, 3WK was supplemented on d 0, 2, 4, 7, 9, 11, 14, 16, and 18 whereas 1WK was supplemented on d 4, 11, and 18. Blood samples were collected from 0 (before) to 72 h after supplementation on d 11 and 18 and analyzed for plasma urea-N (PUN). Samples collected from 0 to 12 h were also analyzed for plasma glucose, insulin, and P4 (d 18 only). Uterine flushing fluid was collected concurrently with blood sampling at 28 h for pH evaluation. Liver biopsies were performed concurrently with blood sampling at 0, 4, and 28 h and analyzed for mRNA expression of carbamoyl phosphate synthetase I (CPS-I; h 28) and CYP2C19 and CYP3A4 (h 0 and 4 on d 18). Plasma urea-N concentrations were greater (P < 0.01) for 1WK vs. 3WK from 20 to 72 h and greater (P < 0.01) for 1WK vs. D from 16 to 48 h and at 72 h after supplementation (treatment × hour interaction, P < 0.01). Moreover, PUN concentrations peaked at 28 h after supplementation for 3WK and 1WK (P < 0.01) and were greater (P < 0.01) at this time for 1WK vs. 3WK and D and for 3WK vs. D. Expression of CPS-I was greater (P < 0.01) for 1WK vs. D and 3WK. Uterine flushing pH tended (P ≤ 0.10) to be greater for 1WK vs. 3WK and D. No treatment effects were detected (P ≥ 0.15) on expression of CYP2C19 and CYP3A4, plasma glucose, and P4 concentrations, whereas plasma insulin concentrations were greater (P ≤ 0.03) in D and 3WK vs. 1WK. Hence, decreasing frequency of protein supplementation did not reduce uterine flushing pH or plasma P4 concentrations, which are known to impact reproduction in beef cows.


Asunto(s)
Dieta/veterinaria , Proteínas en la Dieta/farmacología , Suplementos Dietéticos , Sincronización del Estro/efectos de los fármacos , Inseminación Artificial/veterinaria , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Nitrógeno de la Urea Sanguínea , Bovinos , Proteínas en la Dieta/administración & dosificación , Dinoprost/farmacología , Femenino , Hormona Liberadora de Gonadotropina/farmacología , Insulina/sangre , Embarazo , Progesterona/sangre , Reproducción/fisiología , Glycine max
11.
J Anim Sci ; 92(9): 4137-44, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25023798

RESUMEN

This experiment evaluated the effects of meloxicam administration on physiological and performance responses of transported cattle during feedlot receiving. Eighty-four Angus × Hereford steers were ranked by BW on d -10 and assigned to 21 dry lot pens. From d -10 to 0, pens were fed alfalfa-grass hay ad libitum and 2.4 kg/steer daily (DM basis) of a corn-based concentrate. On d 0, pens were randomly assigned to 1) transport for 1,440 km in a livestock trailer and oral administration of meloxicam (1 mg/kg of BW) at loading (d 0), unloading (d 1), and daily from d 2 to 7 of feedlot receiving (MEL; n = 7); 2) the same transportation and treatment schedule of MEL but oral administration of lactose monohydrate (1 mg/kg of BW) instead of meloxicam (TRANS; n = 7); or 3) no transport and oral administration of lactose monohydrate (1 mg/kg of BW) concurrently with treatment administration to MEL and TRANS (CON; n = 7). Upon arrival (d 1), MEL and TRANS steers returned to their pens for a 21-d feedlot receiving with the same diet offered from d -10 to 0. Treatments were administered to steers via oral drench on d 0 and 1 or mixed daily with the concentrate from d 2 to 7. Full BW was recorded before (d -2, -1, and 0) treatment application and at the end of experiment (d 20, 21, and 22) for ADG calculation. Daily DMI was recorded from d 1 to 21. Blood samples were collected on d 0, 1, 3, 5, 7, 10, 14, and 21. During the initial 7 d of feedlot receiving, hay and total DMI were reduced (P ≤ 0.03) in TRANS vs. CON and MEL and similar between CON and MEL (P ≥ 0.26), whereas concentrate DMI did not differ (P = 0.16) among treatments. Mean ADG was reduced (P ≤ 0.03) in TRANS vs. MEL and CON but similar (P = 0.82) between MEL and CON. Moreover, TRANS had reduced G:F vs. CON (P = 0.01) and MEL (P = 0.05), whereas G:F was similar (P = 0.39) between CON and MEL. Serum NEFA concentrations were greater (P < 0.01) for TRANS and MEL vs. CON on d 1. Plasma haptoglobin concentrations were greater (P ≤ 0.03) for TRANS vs. CON and MEL on d 5 and greater (P ≤ 0.03) for CON vs. TRANS on d 10. Plasma ceruloplasmin concentrations were greater (P ≤ 0.04) for TRANS vs. CON on d 3, 5, 7, 10, and 14, greater (P ≤ 0.03) for TRANS vs. MEL on d 5 and 7, and also greater (P = 0.05) for MEL vs. CON on d 3. In conclusion, meloxicam administration to feeder steers modulated the haptoglobin and ceruloplasmin responses and prevented the performance losses caused by long-distance transportation.


Asunto(s)
Peso Corporal/efectos de los fármacos , Bovinos/crecimiento & desarrollo , Tiazinas/farmacología , Tiazoles/farmacología , Transportes/métodos , Administración Oral , Animales , Ceruloplasmina/metabolismo , Dieta/veterinaria , Haptoglobinas/metabolismo , Meloxicam , Tiazinas/administración & dosificación , Tiazoles/administración & dosificación
12.
J Anim Sci ; 92(6): 2725-34, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24713166

RESUMEN

This experiment evaluated the influence of supplement composition on performance, reproductive, and metabolic responses of Angus × Hereford heifers consuming a low-quality cool-season forage (8.7% CP and 57% TDN). Sixty heifers (initial age = 226 ± 3 d) were allocated into 15 drylot pens (4 heifers/pen and 5 pens/treatment) and assigned to 1) supplementation with soybean meal (PROT), 2) supplementation with a mixture of cracked corn, soybean meal, and urea (68:22:10 ratio, DM basis; ENER), or 3) no supplementation (CON). Heifers were offered meadow foxtail (Alopecurus pratensis L.) hay for ad libitum consumption during the experiment (d -10 to 160). Beginning on d 0, PROT and ENER were provided daily at a rate of 1.30 and 1.40 kg of DM/heifer to ensure that PROT and ENER intakes were isocaloric and isonitrogenous. Hay and total DMI were recorded for 5 consecutive days during each month of the experiment. Blood was collected every 10 d for analysis of plasma progesterone to evaluate puberty attainment. Blood samples collected on d -10, 60, 120, and 150 were also analyzed for plasma concentrations of plasma urea N (PUN), glucose, insulin, IGF-I, NEFA, and leptin. Liver samples were collected on d 100 from 2 heifers/pen and analyzed for mRNA expression of genes associated with nutritional metabolism. No treatment effect was detected (P = 0.33) on forage DMI. Total DMI, ADG, and mean concentrations of glucose, insulin, and IGF-I as well as hepatic mRNA expression of IGF-I and IGFBP-3 were greater (P ≤ 0.02) for PROT and ENER compared with CON and similar between PROT and ENER (P ≥ 0.13). Mean PUN concentrations were also greater (P < 0.01) for PROT and ENER compared with CON, whereas PROT heifers had greater (P < 0.01) PUN compared with ENER. Plasma leptin concentrations were similar between ENER and PROT (P ≥ 0.19) and greater (P ≤ 0.03) for ENER and PROT compared with CON on d 120 and 150 (treatment × day interaction, P = 0.03). Hepatic mRNA expression of mitochondrial phosphoenolpyruvate carboxykinase was greater (P = 0.05) in PROT compared with CON and ENER and similar between CON and ENER (P = 0.98). The proportion of heifers pubertal on d 160 was greater (P < 0.01) in ENER compared with PROT and CON and similar between PROT and CON (P = 0.38). In conclusion, beef heifers consuming a low-quality cool-season forage had a similar increase in DMI, growth, and overall metabolic status if offered supplements based on soybean meal or corn at 0.5% of BW.


Asunto(s)
Bovinos/fisiología , Glycine max , Reproducción/fisiología , Estaciones del Año , Maduración Sexual/fisiología , Zea mays , Animales , Glucemia/metabolismo , Nitrógeno de la Urea Sanguínea , Suplementos Dietéticos , Femenino , Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Leptina/sangre , Hígado/metabolismo , Mitocondrias/metabolismo , Fosfoenolpiruvato Carboxiquinasa (ATP)/metabolismo , Poaceae , Progesterona/sangre
13.
J Anim Sci ; 91(12): 5905-11, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24085412

RESUMEN

This experiment evaluated temperament, vaginal temperature, and plasma cortisol in beef cows from wolf-naïve and wolf-experienced origins that were subjected to a simulated wolf encounter. Multiparous, pregnant, nonlactating Angus-crossbreed cows from the Eastern Oregon Agricultural Research Center located near Burns, OR (CON; n = 50), and from a commercial operation near Council, ID (WLF; n = 50), were used. To date, grey wolves are not present around Burns, OR, and thus CON were naïve to wolves. Conversely, wolves are present around Council, ID, and WLF cows were selected from a herd that had experienced multiple confirmed wolf-predation episodes from 2008 to 2012. Following a 50-d commingling and adaptation period, CON and WLF cows were ranked by temperament, BW, and BCS and allocated to 5 groups (d 0; 10 CON and 10 WLF cows/group). Groups were individually subjected to the experimental procedures on d 2 (n = 3) and d 3 (n = 2). Before the simulated wolf encounter, cow temperament was assessed and blood samples and vaginal temperatures (using intravaginal data loggers) were collected (presimulation assessments). Cows were then sorted by origin, moved to 2 adjacent drylot pens (10 WLF and 10 CON cows/pen), and subjected to a simulated wolf encounter event for 20 min, which consisted of 1) cotton plugs saturated with wolf urine attached to the drylot fence, 2) continuous reproduction of wolf howls, and 3) 3 leashed dogs that were walked along the fence perimeter. Thereafter, WLF and CON cows were commingled and returned to the handling facility for postsimulation assessments, which were conducted immediately after exposure to wolf-urine-saturated cotton plugs, wolf howl reproduction, and 20-s exposure to the 3 dogs while being restrained in a squeeze chute. Chute score, temperament score, and plasma cortisol concentration increased (P ≤ 0.01) from pre- to postsimulation assessment in WLF but did not change in CON cows (P ≥ 0.19). Exit velocity decreased (P = 0.01) from pre- to postsimulation assessment in CON but did not change (P = 0.79) in WLF cows. In addition, WLF cows had a greater (P = 0.03) increase in temperature from pre- to postsimulation assessments compared with CON cows. In conclusion, the simulated wolf encounter increased excitability and fear-related physiological stress responses in cows that originated from a wolf-experienced herd but not in cows that originated from a wolf-naïve herd.


Asunto(s)
Conducta Animal/fisiología , Lobos , Animales , Bovinos , Perros , Femenino , Odorantes , Embarazo , Temperamento , Vocalización Animal
14.
J Dairy Sci ; 95(12): 7039-50, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23040021

RESUMEN

Two experiments evaluated milk production, serum progesterone and insulin, and reproductive performance of lactating Holstein cows receiving or not receiving Ca salts of polyunsaturated fatty acids (PUFA), or receiving Ca salts of PUFA at different daily frequencies. In experiment 1, 1,125 cows randomly distributed in 10 freestall barns were enrolled. Barns were assigned randomly to receive a high-concentrate diet containing (PF) or not containing (control, CON) 1.1% (dry matter basis) Ca salts of PUFA. Diets were offered 6 times daily, whereas the Ca salts of PUFA were included in the PF treatment in the first feeding of the day. In experiment 2, 1,572 cows were randomly distributed in 10 freestall barns, which were assigned randomly to receive a diet similar to PF, but with Ca salts of PUFA included only in the first feeding of the day (PF1X), or equally distributed across all 6 feedings (PF6X). During both experiments, cows were artificially inseminated 12 h after the onset of estrus. Once per month, cows that did not conceive to artificial insemination were assigned to a fixed-time embryo transfer protocol. Pregnancy was determined via transrectal ultrasonography 28 and 60 d after expected ovulation. Pregnancy loss was considered in cows that were pregnant on d 28 but nonpregnant on d 60. During both experiments, feed intake, milk yield, and milk protein and fat content were recorded weekly. Blood samples were collected concurrently with embryo transfer. During experiment 1, feed intake was similar between treatments. Compared with CON, PF cows had greater milk yield (37.8 vs. 35.3 kg/d), and reduced milk fat content (3.41 vs. 3.55%). However, PF cows had reduced pregnancy losses per service compared with CON (12.6 vs. 18.3%). Serum progesterone was greater and serum insulin tended to be greater in primiparous cows receiving PF compared with CON cohorts (4.50 vs. 3.67 ng of progesterone/mL, and 10.4 vs. 7.5 µUI of insulin/mL). During experiment 2, no treatment effects were detected for feed intake, milk yield, or milk fat, whereas PF1X cows tended to have reduced pregnancy losses per service compared with PF6X (14.4 vs. 18.4%). In summary, feeding Ca salts of PUFA to dairy cows increased milk production, did not alter feed intake, and reduced pregnancy losses per service. Further, the total daily amount of Ca salts of PUFA should be fed during the first feeding of the day to optimize its benefits on pregnancy maintenance of dairy cows.


Asunto(s)
Calcio/farmacología , Bovinos/fisiología , Ácidos Grasos Insaturados/farmacología , Lactancia/fisiología , Animales , Dieta/veterinaria , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Femenino , Fertilidad/efectos de los fármacos , Fertilidad/fisiología , Inseminación Artificial/fisiología , Inseminación Artificial/veterinaria , Lactancia/efectos de los fármacos , Leche/metabolismo , Paridad , Embarazo/efectos de los fármacos , Embarazo/fisiología , Reproducción/efectos de los fármacos , Reproducción/fisiología
15.
J Anim Sci ; 90(9): 3266-73, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22585806

RESUMEN

Three experiments were conducted to evaluate plasma concentrations of glucose, insulin, IGF-I, and progesterone (P4) in pubertal beef heifers receiving exogenous glucose, insulin, or sometribove zinc. All heifers used had no luteal P4 synthesis but received a controlled internal drug-releasing device containing 1.38 g of P4 to estimate treatment effects on hepatic P4 degradation. In Exp. 1, 8 pubertal, nulliparous Angus × Hereford heifers (initial BW = 442 ± 14 kg; initial age = 656 ± 7 d) were randomly assigned to receive, in a crossover design containing 2 periods of 10 h, intravenous (i.v.) infusions (10 mL) of insulin (1 µg/kg of BW; INS) or saline (0.9%; SAL). Treatments were administered via jugular venipuncture in 7 applications (0.15 µg insulin/kg BW per application) 45 min apart (from 0 to 270 min). Blood samples were collected immediately before each infusion as well as at -120, -60, 330, 390, and 450 min relative to the first infusion. Heifers receiving INS had greater (P < 0.01) plasma insulin, reduced (P ≤ 0.04) plasma glucose and IGF-I, and similar (P = 0.62) plasma P4 concentrations compared with SAL heifers. In Exp. 2, the same heifers were assigned to receive, in a similar experimental design as Exp. 1, i.v. infusions (10 mL) of 1) insulin (1 µg/kg BW) and glucose (0.5 g/kg BW; INS+G) or 2) SAL. Heifers receiving INS+G had greater (P ≤ 0.02) plasma insulin, glucose, and P4 but reduced (P = 0.01) plasma IGF-I concentrations compared with SAL heifers. In Exp. 3, the same heifers were assigned to receive, in a crossover design containing 2 periods of 14 d, subcutaneous (s.c.) injections of 1) 250 mg of sometribove zinc (BST) or 2) SAL. Blood samples were collected 3 h apart (0900, 1200, 1500, and 1800 h) from heifers on d 6, 8, and 10 relative to treatment administration (d 1). Heifers receiving BST had greater (P < 0.01) plasma glucose and IGF-I and similar (P ≥ 0.67) plasma insulin and P4 concentrations compared with SAL heifers. Results from this series of experiments suggested that concurrent increases in glucose and insulin are required to reduce hepatic catabolism and increase plasma concentrations of P4 in bovine females.


Asunto(s)
Bovinos/sangre , Glucosa/farmacología , Hormona del Crecimiento/farmacología , Insulina/farmacología , Progesterona/sangre , Animales , Glucemia , Estudios Cruzados , Femenino , Glucosa/administración & dosificación , Hormona del Crecimiento/administración & dosificación , Insulina/administración & dosificación , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo
16.
J Anim Sci ; 89(10): 3116-24, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21622871

RESUMEN

Five experiments evaluated the effects of supplemental Ca salts of PUFA on reproductive function of Bos indicus beef cows. In Exp. 1, nonlactating and multiparous grazing cows (n = 51) were assigned to receive (as-fed basis) 0.1 kg of a protein-mineral mix + 0.1 kg of ground corn per cow/d, in addition to 0.1 kg per cow/d of 1) Ca salts of PUFA (PF), 2) Ca salts of SFA (SF), or 3) kaolin (control). Treatments were offered from d 0 to 20 of the estrous cycle. No treatment effects were detected on serum progesterone concentrations (P = 0.83), day of luteolysis (P = 0.86), or incidence of short cycles (P = 0.84). In Exp. 2, nonlactating and multiparous grazing cows (n = 43) were assigned to receive PF, SF, or control from d 0 to 8 of the estrous cycle. On d 6, all cows received (intramuscularly) 25 mg of PGF(2α). No treatment effects were detected on serum progesterone concentrations on d 6 (P = 0.37), and incidence (P = 0.67) or estimated time of luteolysis (P = 0.44). In Exp. 3, twenty-seven lactating and multiparous grazing cows, approximately 30 to 40 d postpartum, were assigned to receive PF or control for 10 d beginning at the first postpartum ovulation. No treatment effects were detected (P = 0.85) on incidence of short cycles. In Exp. 4, lactating and multiparous grazing cows (n = 1,454), approximately 40 to 60 d postpartum, were assigned to receive 1 of the 7 treatments for 28 d after timed AI (TAI; d 0): 1) control from d 0 to 28, 2) SF from d 0 to 14 and then control, 3) PF from d 0 to 14 and then control, 4) SF from d 0 to 21 and then control, 5) PF from d 0 to 21 and then control, 6) SF from d 0 to 28, and 7) PF from d 0 to 28. Cows receiving PF for more than 21 d after TAI had greater (P < 0.01) pregnancy to TAI compared with all other treatments combined (50.4 vs. 42.4%, respectively). In Exp. 5, lactating and multiparous grazing cows (n = 501), approximately 40 to 60 d postpartum, were assigned to receive 1 of the 4 treatments for 21 d after TAI (d 0): 1) PF from d 0 to 14 and then control, 2) control from d 0 to 6 and then PF, 3) control from d 0 to 13 and then PF, and 4) PF from d 0 to 21. Cows receiving PF after d 14 of the experiment had greater (P = 0.02) pregnancy to TAI compared with cows not receiving PF during the same period (46.8 vs. 33.1%, respectively). In summary, supplemental Ca salts of PUFA during the expected time of luteolysis increased pregnancy to TAI in beef cows.


Asunto(s)
Alimentación Animal/análisis , Calcio/química , Bovinos , Dieta/veterinaria , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Suplementos Dietéticos , Dinoprostona/farmacología , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Fármacos para la Fertilidad Femenina/farmacología , Caolín , Ovulación , Embarazo
17.
Meat Sci ; 86(4): 999-1004, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20826070

RESUMEN

The potential of near infrared (NIR) spectroscopy as an on-line method to quantify glycogen and predict ultimate pH (pH(u)) of pre rigor beef M. longissimus dorsi (LD) was assessed. NIR spectra (538 to 1677 nm) of pre rigor LD from steers, cows and bulls were collected early post mortem and measurements were made for pre rigor glycogen concentration and pH(u). Spectral and measured data were combined to develop models to quantify glycogen and predict the pH(u) of pre rigor LD. NIR spectra and pre rigor predicted values obtained from quantitative models were shown to be poorly correlated against glycogen and pH(u) (r(2)=0.23 and 0.20, respectively). Qualitative models developed to categorize each muscle according to their pH(u) were able to correctly categorize 42% of high pH(u) samples. Optimum qualitative and quantitative models derived from NIR spectra found low correlation between predicted values and reference measurements.


Asunto(s)
Análisis de los Alimentos/métodos , Glucógeno/análisis , Carne/análisis , Cambios Post Mortem , Espectroscopía Infrarroja Corta/métodos , Animales , Bovinos , Concentración de Iones de Hidrógeno , Modelos Biológicos , Músculo Esquelético/química , Rigor Mortis
18.
J Med Genet ; 46(5): 319-23, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19279022

RESUMEN

AIM: To establish health related costs and benefits of clinical services for women at increased familial risk of breast cancer. METHODS: Analysis of costs and outcomes for one UK regional service, supplemented with data from a multinational collaborative study. Main outcome measures were aggregate costs for regular clinical examination, mammographic screening and further investigations; breast cancer incidence; proportion of cancers detected at "early" or "late" stage, compared with corresponding data for unscreened women of comparable age; survival in relation to stage at diagnosis; itemised and aggregate costs of management for "early" and "late" stage breast cancer; hence direct health care costs per quality adjusted life-year (QALY) gained. RESULTS: The surveillance programme costs pound1500 (euro1600, US$2100) per woman (over 15 years). Breast cancer incidence is close to 6 per thousand examinations; 75% of tumours are detected through screening and 77% are "early" (path stage 1 or 2). Corresponding figures for unscreened women (including relatives of those attending the breast cancer family clinic) indicate that surveillance achieves a beneficial "stage shift", with reduction in treatment costs and improvement in survival, in about 22% of cases. CONCLUSIONS: The current clinical service for women at familial risk of breast cancer costs about pound4800 (euro5200, US$6800) per QALY gained. That figure is sensitive to the rate of detection of breast cancer and the degree of beneficial stage shift achieved. Within the realistic range of estimates for these two parameters, the cost per QALY may be as high as pound14,000 (euro15,300, US$20,000) or as low as pound1000 (euro1100, US$1400).


Asunto(s)
Neoplasias de la Mama/terapia , Vigilancia de la Población/métodos , Adulto , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/economía , Neoplasias de la Mama/genética , Análisis Costo-Beneficio/métodos , Salud de la Familia , Femenino , Humanos , Persona de Mediana Edad , Mutación , Años de Vida Ajustados por Calidad de Vida , Análisis de Supervivencia
19.
Scand J Immunol ; 66(2-3): 362-71, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17635814

RESUMEN

Human chronic Chagas disease cardiomyopathy (CCC) is an inflammatory-dilated cardiomyopathy occurring years after infection by the protozoan Trypanosoma cruzi. The heart inflammatory infiltrate in CCC shows a 2:1 predominance of CD8(+) in relation to CD4(+) T cells, with a typical Th1-type cytokine profile. However, in vitro expansion of infiltrating T cells from heart biopsy-derived fragments with interleukin-2 (IL-2) and phytohaemagglutinin leads to the outgrowth of CD4(+) over CD8(+) T cells. We hypothesized that survival cytokines, such as IL-2, IL-7 and IL-15 might be differentially involved in the growth and maintenance of heart-infiltrating and peripheral CD8(+) T cells from CCC patients. We found that IL-7 and IL-15 were superior to IL-2 in the expansion and viability of CD8(+) T cells from both PBMC and heart-infiltrating T-cell lines from CCC patients, and the combination of the three cytokines showed synergic effects. Heart-infiltrating CD8(+) T cells showed higher expression of both IL-15R alpha and gamma(c) chain than CD4(+) T cells, which may explain the improvement of CD8(+) T-cell growth in the presence of IL-2 + IL-7 + IL-15. Immunohistochemical identification of IL-15 and the higher mRNA expression of IL-15R alpha, IL-7 and gamma(c) chain in CCC heart tissues compared with control individuals indicate in situ production of survival cytokines and their receptors in CCC hearts. Together, our results suggest that local production of IL-7 and IL-15 may be associated with the maintenance and predominance of CD8(+) T cells, the cells effecting tissue damage in CCC hearts.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Cardiomiopatía Chagásica/inmunología , Cardiomiopatía Chagásica/patología , Interleucina-15/biosíntesis , Interleucina-7/biosíntesis , Miocardio/inmunología , Miocardio/patología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/metabolismo , Línea Celular , Movimiento Celular/inmunología , Proliferación Celular , Supervivencia Celular/inmunología , Cardiomiopatía Chagásica/metabolismo , Enfermedad Crónica , Humanos , Inmunofenotipificación , Interleucina-15/fisiología , Interleucina-2/biosíntesis , Interleucina-2/fisiología , Interleucina-7/fisiología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Recuento de Linfocitos , Miocardio/metabolismo
20.
Waste Manag ; 24(9): 889-97, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15504666

RESUMEN

The present paper aims to make the energy saving potential provided by waste recycling in Brazil evident by pointing out more specifically the benefits regarding climate change mitigation. In this case, based on the energy saved due to the recycling process of an exogenous amount of waste, we have built two scenarios in order to show the potential for indirectly avoiding CO2 emissions in the country as a result of the recycling process. According to the scenario, 1 Mt and 3.5 Mt of CO2, respectively, would be avoided per year due to solid waste recycling. The international context for greenhouse gas emissions reduction, such as the United Nations Framework Convention on Climate Change and its Kyoto Protocol has been taken into account.


Asunto(s)
Dióxido de Carbono , Conservación de los Recursos Energéticos/métodos , Eliminación de Residuos/métodos , Contaminantes Atmosféricos , Brasil , Centrales Eléctricas
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