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1.
J Dairy Sci ; 101(9): 8135-8145, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30007809

RESUMO

Group housing and computerized feeding of preweaned dairy calves are gaining in popularity among dairy producers, yet disease detection remains a challenge for this management system. The aim of this study was to investigate the application of statistical process control charting techniques to daily average feeding behavior to predict and detect illness and to describe the diagnostic test characteristics of using this technique to find a sick calf compared with detection by calf personnel. This prospective cross-sectional study was conducted on 10 farms in Minnesota (n = 4) and Virginia (n = 6) utilizing group housing and computerized feeding from February until October 2014. Calves were enrolled upon entrance to the group pen. Calf personnel recorded morbidity and mortality events. Farms were visited either every week (MN) or every other week (VA) to collect calf enrollment data, computer-derived feeding behavior data, and calf personnel-recorded calf morbidity and mortality. Standardized self-starting cumulative sum (CUSUM) charts were generated for each calf for each daily average feeding behavior, including drinking speed (mL/min), milk consumption (L/d), and visits to the feeder without a milk meal (no.). A testing subset of 352 calves (176 treated, 176 healthy) was first used to find CUSUM chart parameters that provided the highest diagnostic test sensitivity and best signal timing, which were then applied to all calves (n = 1,052). Generalized estimating equations were used to estimate the diagnostic test characteristics of a single negative mean CUSUM chart signal to detect a sick calf for a single feeding behavior. Combinations of feeding behavior signals were also explored. Single signals and combinations of signals that included drinking speed provided the most sensitive and timely signal, finding a sick calf up to an average (±SE) of 3.1 ± 8.8 d before calf personnel. However, there was no clear advantage to using CUSUM charting over calf observation for any one feeding behavior or combination of feeding behaviors when predictive values were considered. The results of this study suggest that, for the feeding behaviors monitored, the use of CUSUM control charts does not provide sufficient sensitivity or predictive values to detect a sick calf in a timely manner compared with calf personnel. This approach to examining daily average feeding behaviors cannot take the place of careful daily observation.


Assuntos
Doenças dos Bovinos/epidemiologia , Comportamento Alimentar , Abrigo para Animais , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Estudos Transversais , Minnesota , Estudos Prospectivos , Virginia
2.
J Dairy Sci ; 100(7): 5642-5652, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28478006

RESUMO

Group housing and computerized feeding of preweaned dairy calves is gaining popularity among dairy producers worldwide, yet disease incidence and detection remain a challenge in these systems. The aim of this prospective observational cohort study was to describe the relationship between morbidity and feeding behavior around the period of illness detection. Calves were enrolled upon entrance to the group pen on 10 farms in Minnesota (n = 4) and Virginia (n = 6) utilizing group housing and computerized feeding from February until October 2014. Morbidity and mortality events were recorded by the calf caregiver. Farms were visited either every week (Minnesota) or every other week (Virginia) to collect calf enrollment data, feeding behavior data, and health records. Daily average feeding behaviors (drinking speed, mL/min; daily consumption, L/d; rewarded visits to the feeder; and unrewarded visits to the feeder) were described both overall and for sick and healthy calf days. Multivariable mixed models were built to assess the differences in daily average feeding behaviors (drinking speed, daily consumption, rewarded visits, unrewarded visits) between matched sick and healthy calves around the time of an illness event (-10 to 10 d). Final models were controlled for calf age, region (Minnesota and Virginia), group size, disease diagnosis, the random effect of farm, and repeated measurements on calf. A stratified analysis was performed by both day from treatment event and disease diagnosis. We enrolled 1,052 calves representing 43,607 calf days over 9 mo. From these, 176 sick calves had a matched control and were carried forward to the matched pair analysis. Fifty-five percent of sick calves (97/176) were treated for diarrhea, 30% (53/176) were treated for pneumonia, and 15% (26/176) were treated for ill thrift. Sick calves drank 183 ± 27 mL/min (mean ± standard error) more slowly, drank 1.2 ± 0.6 L/d less, and had 3.1 ± 0.7 fewer unrewarded visits than control calves on the first day of treatment. These differences began up to 4 d before the calf was detected as sick, and persisted for 7 to 10 d after treatment. However, changes in feeding behaviors varied by disease diagnosed. Rewarded visits were not associated with morbidity status. The results of this study indicate that sick calves change their feeding behavior before and during an illness event, suggesting that feeding behavior may be a useful tool to detect disease onset.


Assuntos
Doenças dos Bovinos/fisiopatologia , Comportamento Alimentar , Métodos de Alimentação/veterinária , Criação de Animais Domésticos/métodos , Animais , Bovinos , Doenças dos Bovinos/terapia , Diarreia/terapia , Diarreia/veterinária , Comportamento de Ingestão de Líquido , Métodos de Alimentação/instrumentação , Abrigo para Animais , Minnesota , Estudos Observacionais como Assunto , Pneumonia/terapia , Pneumonia/veterinária , Fatores de Tempo , Virginia
3.
J Dairy Sci ; 99(5): 3995-4004, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26898286

RESUMO

Research has shown that changes in nutrition both before and after weaning can affect mammary development. Additionally, estrogen is known to be a potent mammogenic stimulant. Our objectives were to determine effects of altered preweaning feeding and exogenous estradiol postweaning on growth, intake, and health. Thirty-six Holstein heifer calves were reared on (1) a restricted milk replacer (MR) diet fed at 0.44kg powder dry matter (DM)/day [R; 20.9% crude protein (CP), 19.8% fat, DM basis], or (2) an enhanced MR fed at 1.08kg powder DM/d (EH; 28.9% CP, 26.2% fat, DM basis). The MR feeding was reduced 50% during wk 8 to prepare for weaning. Starter was offered after wk 4 but balanced between treatments. Body weight and frame were measured weekly with intakes and health monitored daily. At weaning, a subset of calves were slaughtered (n=6/diet). Enhanced-fed calves had greater carcass, thymus, liver, spleen, and mammary gland (parenchyma and mammary fat pad) weights. The EH calves also had greater average daily gain (ADG) starting during wk 1 (0.36 vs. -0.06kg/d) and lasting through wk 7 (1.00 vs. 0.41kg/d). Remaining calves received estrogen implants or placebo and were slaughtered at the end of wk 10, creating 4 treatments: (1) R, (2) R + estrogen (R-E2), (3) EH, and (4) EH + estrogen (EH-E2). Postweaning ADG was similar between R, EH, and EH-E2 calves, but greater in R-E2 calves than E calves. The EH-E2 calves had the heaviest mammary glands, and R-E2 calves had heavier mammary glands than R calves. The EH calves consumed more MR DM, CP, and fat preweaning. The R-fed calves consumed more starter DM preweaning. Fecal score was greater for EH calves (1.74 vs. 1.50) preweaning, but days medicated did not differ. Fecal scores were lower for R-E2 calves postweaning. Improved preweaning feeding of calves increased body weights and frame measures. Differences in body weights remained postweaning. Enhanced-fed calves showed greater ADG during the preweaning period but not postweaning. Exogenous estrogen may elicit diet-dependent growth responses. Analysis of collected samples will allow determination of cellular and molecular processes responsible for the marked differences in mammary development observed.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Estradiol/farmacologia , Desmame , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/crescimento & desenvolvimento , Feminino , Glândulas Mamárias Animais/crescimento & desenvolvimento , Estado Nutricional , Distribuição Aleatória
4.
J Dairy Sci ; 99(2): 1237-1241, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26709165

RESUMO

The objective of the current work was to use digestion coefficients from the Feng et al. (2015) model (Virginia Tech model) to calculate P bioavailability of common feeds used in dairy production. Compared with the bioavailability calculated by the Virginia Tech model, using the NRC (2001) P absorption coefficient of 0.64 for forages would underestimate the bioavailabilities of alfalfa hay, alfalfa silage, corn silage, grass hay, and mixed mainly legume silage. For concentrates, using the NRC (2001) P absorption coefficient of 0.70 would overestimate the bioavailabilities of corn grain but underestimate bioavailability of high-moisture corn. Two dairy diets were formulated using nutrient values from the NRC (2001): a standard diet that includes minimal by-products, and a by-product diet that has reduced corn and soybean meal which was replaced with corn gluten feed, distillers grains, hominy feed, and wet brewers grains. For each diet, total bioavailable P was calculated using availability values from the NRC (2001) and the Virginia Tech model. Comparison of P balance (the difference between required and bioavailable P) for each diet was made using the 2 sets of bioavailabilities for a reference cow weighing 682 kg, producing 38.6 kg of milk/d (3.5% fat and 3.0% true protein, 100 d in milk), and consuming 23 kg of dry matter/d, yielding an absorbed P requirement of 59.4 g/d. The standard diet supplied 56.69 and 53.52 g of bioavailable P per day using bioavailabilities from the NRC (2001) and Virginia Tech models, respectively, resulting in a P balance of -2.71 and -5.88±0.26 g/d. The by-product diet provided 75.75 and 78.47 g/d of bioavailable P, yielding P balances of 16.35 and 19.07±0.37 g per day, respectively, using the 2 sets of bioavailabilities. Using P bioavailabilities for individual ingredients that were based on the Virginia Tech model resulted in different bioavailable P levels thus resulted in differing dietary P balances in a field setting.


Assuntos
Ração Animal , Bovinos/metabolismo , Fósforo na Dieta/farmacocinética , Animais , Disponibilidade Biológica , Indústria de Laticínios , Dieta/veterinária , Proteínas Alimentares , Digestão , Feminino , Glutens , Lactação/metabolismo , Medicago sativa , Modelos Biológicos , Silagem/análise , Virginia , Zea mays
5.
J Dairy Sci ; 99(5): 3979-3994, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26923041

RESUMO

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


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

RESUMO

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


Assuntos
Animais Recém-Nascidos , Bovinos/imunologia , Colostro/citologia , Colostro/imunologia , Animais , Líquidos Corporais , Bovinos/fisiologia , Feminino , Imunoglobulina G/sangue , Leucócitos Mononucleares , Gravidez , Aumento de Peso
7.
Biomolecules ; 13(12)2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-38136628

RESUMO

Glycine receptors (GlyRs) are glycine-gated inhibitory pentameric ligand-gated ion channels composed of α or α + ß subunits. A number of structures of these proteins have been reported, but to date, these have only revealed details of the extracellular and transmembrane domains, with the intracellular domain (ICD) remaining uncharacterised due to its high flexibility. The ICD is a region that can modulate function in addition to being critical for receptor localisation and clustering via proteins such as gephyrin. Here, we use modelling and molecular dynamics (MD) to reveal details of the ICDs of both homomeric and heteromeric GlyR. At their N and C ends, both the α and ß subunit ICDs have short helices, which are major sites of stabilising interactions; there is a large flexible loop between them capable of forming transient secondary structures. The α subunit can affect the ß subunit ICD structure, which is more flexible in a 4α2:1ß than in a 4α1:1ß GlyR. We also explore the effects of gephyrin binding by creating GlyR models bound to the gephyrin E domain; MD simulations suggest these are more stable than the unbound forms, and again there are α subunit-dependent differences, despite the fact the gephyrin binds to the ß subunit. The bound models also suggest that gephyrin causes compaction of the ICD. Overall, the data expand our knowledge of this important receptor protein and in particular clarify features of the underexplored ICD.


Assuntos
Simulação de Dinâmica Molecular , Receptores de Glicina , Receptores de Glicina/metabolismo , Proteínas de Transporte/metabolismo , Glicina
8.
J Dairy Sci ; 95(12): 7261-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23040023

RESUMO

Milk urea nitrogen (MUN) is correlated with N balance, N intake, and dietary N content, and thus is a good indicator of proper feeding management with respect to protein. It is commonly used to monitor feeding programs to achieve environmental goals; however, genetic diversity also exists among cows. It was hypothesized that phenotypic diversity among cows could bias feed management decisions when monitoring tools do not consider genetic diversity associated with MUN. The objective of the work was to evaluate the effect of cow and herd variation on MUN. Data from 2 previously published research trials and a field trial were subjected to multivariate regression analyses using a mixed model. Analyses of the research trial data showed that MUN concentrations could be predicted equally well from diet composition, milk yield, and milk components regardless of whether dry matter intake was included in the regression model. This indicated that cow and herd variation could be accurately estimated from field trial data when feed intake was not known. Milk urea N was correlated with dietary protein and neutral detergent fiber content, milk yield, milk protein content, and days in milk for both data sets. Cow was a highly significant determinant of MUN regardless of the data set used, and herd trended to significance for the field trial data. When all other variables were held constant, a percentage unit change in dietary protein concentration resulted in a 1.1mg/dL change in MUN. Least squares means estimates of MUN concentrations across herds ranged from a low of 13.6 mg/dL to a high of 17.3 mg/dL. If the observed MUN for the high herd were caused solely by high crude protein feeding, then the herd would have to reduce dietary protein to a concentration of 12.8% of dry matter to achieve a MUN concentration of 12 mg/dL, likely resulting in lost milk production. If the observed phenotypic variation is due to genetic differences among cows, genetic choices could result in herds that exceed target values for MUN when adhering to best management practices, which is consistent with the trend for differences in MUN among herds.


Assuntos
Bovinos/metabolismo , Leite/química , Ureia/análise , Animais , Dieta/veterinária , Ingestão de Alimentos , Feminino , Lactação/metabolismo , Nitrogênio/análise
9.
PLoS One ; 15(7): e0232784, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32639956

RESUMO

PURPOSE: Rod and cone photoreceptor-specific tests can be time-consuming. A new non-invasive test is described. The test is based on the measurement of flicker modulation thresholds with rod- and cone-enhanced visual stimuli, which requires only minimum adaptation time. Here, we investigated how the rod-and cone-mediated flicker thresholds vary with age. METHODS: Monocular thresholds with rod and cone-enhanced stimuli were measured in 140 healthy adults, (age range: 18-75 years), foveally (0°) and at four parafoveal locations, at an eccentricity of 5° in each of the four quadrants using five, adaptive, interleaved staircases. Temporal frequencies, stimulus sizes, background luminance and spectral composition, were adjusted appropriately to achieve approximately 1 log unit separation in sensitivity between the rod- and cone-enhanced stimuli. Spectrally calibrated, 'neutral density' filters were used to enable adequate control of display luminance for rod enhanced stimuli. RESULTS: The magnitude of central and parafoveal rod thresholds was significantly higher than the central and parafoveal cone thresholds, respectively (p < 0.001) in both the age groups. However, the rate of increase in central rod thresholds (y = 0.45x-12.79; linear regression equation) was not significantly steeper than the rate of increase in central (y = 0.29x-8.53) cone thresholds (p = 0.15). Centrally, cone thresholds showed a better correlation with rod central thresholds for the age > 45 years (Spearman correlation, ρ = 0.74, p < 0.001) compared to age ≤ 45 years (ρ = 0.41, p < 0.001). CONCLUSIONS: Thresholds with rod- and cone-enhanced stimuli are largely invariant below 45 years of age and increase rapidly above this age. This age-wise normative database can be used as an effective functional-marker to assess photoreceptor sensitivities in retinal diseases.


Assuntos
Envelhecimento/fisiologia , Fusão Flicker/fisiologia , Estimulação Luminosa , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Limiar Sensorial/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
J Dairy Sci ; 92(12): 5937-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19923598

RESUMO

Overfeeding prepubertal heifers may impair mammary parenchymal growth and reduce milk production, but evidence suggests that increased intake of a high-protein milk replacer before weaning may be beneficial. This study was designed to evaluate effects of milk replacer (MR) composition on mass and composition of mammary parenchyma and fat pad, growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis gene expression, and putative mammary epithelial stem cells. Specifically, we hypothesized that positive effects of faster rates of gain during the preweaning period alter the development, persistence, or activity of populations of putative mammary epithelial stem cells, possibly through involvement of GH/IGF-I axis molecules. Twenty-four newborn heifers were fed 1 of 4 MR diets (n = 6/diet): control [20% crude protein (CP), 21% fat MR fed at 441 g of dry matter (DM)/d], high protein, low fat (28% CP, 20% fat MR fed at 951 g of DM/d), high protein, high fat (27% CP, 28% fat MR fed at 951 g of DM/d), and high protein, high fat+ (27% CP, 28% fat MR fed at 1,431 g of DM/d). Water and starter (20% CP, 1.43% fat) were offered ad libitum. Animals were killed on d 65 and mammary tissue was subjected to biochemical, molecular, and histological examination. No differences in mammary parenchymal mass or composition, with or without adjusting for empty body weight, were detected. Mass was increased and composition of the mammary fat pad was altered by nutrient intake. No diet differences in putative mammary epithelial stem cell abundance or abundance of transcripts for genes of the GH/IGF-I axis were detected. In this study, growth of the mammary epithelium, size of the mammary epithelial stem cell population, and components of the GH/IGF-I axis did not depend on diet. However, an underlying positive correlation between telomerase, a marker of mammary stem cells, and growth of the mammary parenchyma was detected. Implications of diet-induced effects on mammary fat pad and possible effects on subsequent development and function remain to be determined.


Assuntos
Composição Corporal/fisiologia , Bovinos/fisiologia , Dieta/veterinária , Glândulas Mamárias Animais/fisiologia , Substitutos do Leite/química , Tecido Adiposo/metabolismo , Animais , Animais Recém-Nascidos , Bromodesoxiuridina/metabolismo , Bovinos/metabolismo , Ingestão de Alimentos/fisiologia , Feminino , Regulação da Expressão Gênica/fisiologia , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Antígeno Ki-67/metabolismo , Glândulas Mamárias Animais/enzimologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Substitutos do Leite/normas , Telomerase/metabolismo
11.
J Dairy Sci ; 91(7): 2628-40, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18565922

RESUMO

We investigated the effects of increasing dietary protein and energy on concentrations of selected blood metabolites and hormones in Holstein heifers. Twenty-four heifers were fed 1 of 4 milk replacer (MR) diets for 9 wk (n = 6/diet): control [20% crude protein (CP), 21% fat MR fed at 441 g of dry matter (DM)/d], HPLF (28% CP, 20% fat MR fed at 951 g of DM/d), HPHF (27% CP, 28% fat MR fed at 951 g of DM/d), and HPHF+ (27% CP, 28% fat MR fed at 1,431 g of DM/d). Heifers were fed twice daily; water and starter (20% CP, 1.43% fat) were offered free choice and starter orts recorded daily. Serum and plasma aliquots from blood samples collected twice weekly after a 12-h fast were analyzed for insulin-like growth factor (IGF)-I, IGF-binding proteins (IGFBP), growth hormone (GH), insulin, glucose, nonesterified fatty acids, triglyceride, and plasma urea nitrogen concentrations. Only plasma glucose, IGFBP-2, and IGFBP-3 were affected by diet. Dietary treatment differences were only noted when the control was compared with the average of the other 3 diets. The addition of fat to the MR (HPLF vs. HPHF) and increased volume of MR (HPHF vs. HPHF+) had no effect on plasma glucose concentration or relative abundance of IGFBP-2 or IGFBP-3. Heifers fed the control diet had less glucose, greater IGFBP-2, and less IGFBP-3 than the average of the other 3 diets. There was a diet by week interaction for IGF-I. Serum IGF-I concentration in control heifers varied in a quadratic manner with a nadir (20 +/- 4 ng/mL) at wk 4, whereas IGF-I increased linearly in heifers on other diets. Both insulin and triglyceride changed over time in a complex pattern (significant linear and quadratic contrast effects). The greatest concentrations were measured at wk 0.5 with nadirs at wk 6 for both insulin and triglyceride. Serum GH concentration decreased in a linear manner from wk 0.5 to wk 9 in all heifers. Relative abundance of IGFBP-2 was quadratic over time with the greatest amount of IGFBP-2 observed at wk 5. With the exception of glucose, IGF-I, IGFBP-2, and IGFBP-3, the blood variables measured were not influenced by treatment. The IGF-I -GH-IGFBP axis requires further study in heifers to deduce effects of nutrition on hypothalamic regulation of metabolism. We expected to see more treatment differences in concentrations of metabolites involved with protein and fat metabolism. It is likely that the diets used in this study were not diverse enough in composition to elicit such changes or that the efficiency of use of absorbed protein and fat was not different in these animals.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Bovinos/metabolismo , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia/fisiologia , Substitutos do Leite , Ração Animal , Animais , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Bovinos/sangue , Feminino , Hormônio do Crescimento/sangue , Insulina/sangue , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Triglicerídeos/sangue , Desmame
12.
J Dairy Sci ; 91(8): 3145-55, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18650291

RESUMO

Twenty-four newborn Holstein heifer calves were fed 1 of 4 milk replacers (MR): control (20% CP, 21% fat; MR fed at 441 g/d); high protein/low fat (HPLF; 28% CP, 20% fat; MR fed at 951 g/d); high protein/high fat (HPHF; 27% CP, 28% fat; MR fed at 951 g/d); and HPHF MR fed at a higher rate (HPHF+; 27% CP, 28% fat; MR fed at 1,431 g/d). Dry calf starter (20% CP, 1.43% fat) composed of ground corn (44.4%), 48% CP soybean meal (44.4%), cottonseed hulls (11.2%), and molasses (1.0%) was offered free choice. Heifers were obtained from a commercial dairy, blocked by groups of 8 in the order acquired, and randomly assigned to treatments within group. Upon arrival at the research farm, heifers were fed the control for 2 feedings. Treatments were imposed when heifers were 4 +/- 1 d of age. Heifers were on study for 61 +/- 1 d. Body weight and body size measures were taken weekly. Four-day total collection of feed refusals, feces, and urine was initiated at 57 +/- 1 d of age. Heifers were slaughtered at the end of the collection period to evaluate body composition. Preplanned contrasts were used to compare control to all, HPLF to HPHF, and HPHF to HPHF+. Heifers fed the control diet consumed more starter than those fed other treatment diets, but their total dry matter intake and apparent dry matter digestibility were lowest. Fecal output was highest in heifers fed the control diet, whereas urine output and urine N excretion were lowest. Nitrogen intake and urine N excretion were greater for heifers fed HPHF+ compared with HPHF but were not affected by MR fat content (HPLF vs. HPHF). Retention (g/d) of N and P was greater in heifers fed all nutrient-dense diets compared with those fed the control diet, but was not improved by increasing fat in the milk replacer (HPLF vs. HPHF) or by increasing the amount fed. Addition of fat to the milk replacer (HPLF vs. HPHF) increased empty body weight fat content without improving average daily gain or frame measures. Increasing the volume fed (HPHF vs. HPHF+) increased growth rate and empty body weight, but HPHF+ heifers were neither taller nor longer and their carcasses contained more fat. Clear improvements in growth and nutrient retention were observed with more nutrient-dense diets, but most of the improvements were seen with the increased protein intake relative to the control MR; adding fat to the high protein MR did not further improve lean tissue gain.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/metabolismo , Composição Corporal , Bovinos/crescimento & desenvolvimento , Substitutos do Leite/química , Substitutos do Leite/farmacologia , Ração Animal , Animais , Peso Corporal , Dieta/veterinária , Gorduras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Ingestão de Alimentos , Fezes/química , Feminino , Nitrogênio/metabolismo , Tamanho do Órgão , Fósforo/metabolismo , Distribuição Aleatória , Fatores de Tempo , Desmame
13.
J Dairy Sci ; 90(12): 5600-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18024752

RESUMO

Thirty-nine bull calves between 6 and 9 d of age, were assigned to either baseline slaughter or 1 of 4 diets to determine the influence of dietary fat and protein content, at 2 levels of intake, on growth and body composition changes. Calves were assigned to the following diets a 28.5% protein and 16.4% fat milk replacer [MR; 29/16 (n = 9)], 27.3% protein and 33.4% fat MR [27/33 (n = 8)], 20.6% protein and 20.6% fat MR [20/20 (8)], or whole milk [WM (n = 8)]. Calves fed 27/33, 29/16, and WM received 180 g/d of CP to support 650 g of ADG based on predictions from the 2001 NRC. Calves were fed 3 times daily for 4 wk. Weight, hip height, wither height, heart girth, and body length were measured weekly. Weekly plasma samples were analyzed for plasma urea nitrogen, nonesterified fatty acids, and glucose. A subset of calves from each treatment was killed [29/16 (n = 7), 27/33 (n = 6), 20/20 (n = 6), and WM (n = 5)] at the end of wk 4 of treatment; processed for whole-body analysis of fat, protein, ash, and DM; and compared with baseline slaughter calves to estimate composition of empty BW gain. Calves did not differ in average weekly scour score or medication days. Feed efficiency and ADG were greatest for calves fed WM and least for calves fed 20/20; calves fed 29/16 and 27/33 did not differ. Calves fed 27/33 or WM had the greatest % body fat and gained more grams of fat than calves fed other diets. Calves fed 29/16 or 20/20 had similar % fat in empty body as baseline. Differences in % CP, % ash, or % water in empty body and empty BW gain were not detected. Calves fed 27/33 had a trend toward higher NEFA in wk 1 and 2 than calves fed 29/16 or WM. Growth of calves fed 27/33 and 29/16 were similar except that calves fed 29/16 had lower body fat % than calves fed 27/33. Calves on all diets gained less than predicted by the 2001 NRC.


Assuntos
Composição Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Aumento de Peso/efeitos dos fármacos , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Glicemia/análise , Nitrogênio da Ureia Sanguínea , Composição Corporal/fisiologia , Relação Dose-Resposta a Droga , Ácidos Graxos não Esterificados/sangue , Masculino , Distribuição Aleatória
14.
J Dairy Sci ; 90(12): 5634-42, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18024755

RESUMO

The objectives of this study were to evaluate the effects of limit feeding diets containing concentrates or by-products in place of forages on manure and nutrient excretion in growing, gravid heifers. Eighteen Holstein heifers confirmed pregnant were grouped by due date and fed 1 of 3 diets (n = 6 per treatment) for the last 14 wk of pregnancy. Diets were high forage, fed ad libitum (HF); by-product based (BP), fed at the same rate as HF-fed heifers; or low forage (LF), fed at 86% of the HF diet. Diets were designed to supply equal quantities of P, N, and metabolizable energy. Total collection of feces and urine was conducted in wk 14, 10, 6, and 2 prepartum. The HF ration was 90.7% forage, 13.7% crude protein (CP), and contained orchardgrass hay, corn silage, corn grain, soybean meal 44%, and a vitamin-mineral premix. The BP diet was 46.2% forage and 14.0% CP, with 70% of the grain mix space replaced with soybean hulls and cottonseed hulls in a 1:1 ratio, with intake limited to 93% of the dry matter intake (DMI) of HF. The LF ration was 45.3% forage and 17.8% CP, with intake limited to 86% of the DMI of HF. The effect of diet was analyzed with repeated measures, using preplanned contrasts to compare HF with BP and LF with HF and BP. As designed, heifers fed HF and BP had greater DMI than the heifers limit-fed LF, and there was no effect of diet on average daily gain or BW. Intake and digestibility of N were lower, and fecal N excretion was higher, in heifers fed HF and BP than heifers fed LF. Mean feces excretion on both a wet and dry basis was greater for HF heifers compared with BP heifers and less for LF heifers than for HF and BP heifers. Despite differences in urinary output, diet had no effect on urea N excretion, but there was a trend for heifers fed HF and BP rations to excrete less urinary N compared with those fed LF. Compared with HF and BP heifers, LF heifers tended to have lower fecal P excretion and had higher urinary P excretion. Measured manure and urine excretion from heifers fed LF was greater than current American Society of Agricultural and Biological Engineers values, whereas heifers fed HF excreted less manure and urine than predicted. Heifers achieving similar rates of gain from diets differing in forage, grain, and by-product content excreted widely varying quantities of manure.


Assuntos
Bovinos/fisiologia , Fezes/química , Lactação/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Urina/química , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/metabolismo , Defecação/efeitos dos fármacos , Digestão , Ingestão de Alimentos , Feminino , Nitrogênio/administração & dosagem , Fósforo/administração & dosagem , Gravidez , Micção/efeitos dos fármacos , Aumento de Peso
15.
Urology ; 22(5): 532-5, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6649211

RESUMO

We report on a ten-year-old boy with a huge asymptomatic mass found to be a giant hydronephrosis in an ectopic pelvic kidney. Diagnosis and management of giant hydronephrosis are outlined.


Assuntos
Hidronefrose/etiologia , Rim/anormalidades , Pelve , Criança , Humanos , Hidronefrose/diagnóstico por imagem , Masculino , Radiografia
16.
Urology ; 14(6): 545-8, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-574673

RESUMO

During a two-year period, 165 men were evaluated for sexual dysfunction. Most evaluations were conducted on an outpatient basis and required two separate visits. Fifty-one per cent, 47 per cent, and 2 per cent of the patients were found to have functional disorders, organic disorders, and incomplete evaluations, respectively. Treatment recommendations were tailored to each patient using information gathered during the diagnostic evaluation.


Assuntos
Disfunções Sexuais Fisiológicas/diagnóstico , Adolescente , Adulto , Idoso , Alcoolismo/complicações , Criança , Complicações do Diabetes , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Disfunção Erétil/diagnóstico , Disfunção Erétil/etiologia , Disfunção Erétil/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Induração Peniana/complicações , Pênis/irrigação sanguínea , Complicações Pós-Operatórias , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Fisiológicas/terapia , Doenças Vasculares/complicações
17.
Am J Surg ; 145(2): 297-9, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6824147

RESUMO

The incidences of various diseases responsible for the occurrence of a scrotal mass have been reported. The testicular scan was used infrequently but was 100 percent accurate in differentiating inflammatory masses from torsion. Thirteen patients with inflammatory masses (9.8 percent) were explored because torsion was suspected. Perhaps increased use of testicular scanning, or in children, Doppler flow studies, would reduce the need for exploration. Twenty-seven of the 278 patients (9.7 percent) had asymptomatic masses which were explored to rule out malignant disease, and only four of these patients were found to have malignant disease. Nineteen of the patients had cystic lesions and 2 had inflammatory lesions. If ultrasound had been used in the evaluation of these patients, exploration might not have been necessary. When the diagnosis of the scrotal mass is obvious, there is no need for further evaluation and the clinician should proceed to appropriate therapy. However, when the diagnosis is doubtful, patients would benefit from increased application of the available diagnostic studies.


Assuntos
Doenças dos Genitais Masculinos/diagnóstico por imagem , Escroto/diagnóstico por imagem , Adolescente , Adulto , Criança , Cistos/diagnóstico por imagem , Neoplasias dos Genitais Masculinos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Torção do Cordão Espermático/diagnóstico por imagem , Hidrocele Testicular/diagnóstico por imagem , Varicocele/diagnóstico por imagem
18.
Oecologia ; 91(1): 150-152, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28313387

RESUMO

The algal flora was sampled in 15 intertidal rock pools, selected for habitat uniformity within a limited area. The distribution of species agreed closely with that expected at random, whether examined by the distribution of associations, by nesting, by chequerboarding or by incidence functions. The simplest explanation is that differences in specific composition between the pools are caused by chance.

19.
Acta Diabetol ; 41(2): 63-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15224207

RESUMO

Patients with type 2 diabetes who are inadequately controlled on a half-maximal dose of a sulphonylurea may be managed by either increasing the dose of sulphonylurea or adding another agent. In this study, 471 patients inadequately controlled (fasting plasma glucose [FPG] >or=7.0 and

Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Gliclazida/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , Tiazolidinedionas/uso terapêutico , Adulto , Idoso , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Rosiglitazona
20.
Res Vet Sci ; 21(2): 232-7, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-968192

RESUMO

The anthelmintic efficacy of fenbendazole (methyl 5-(phenylthio)-2-benzimidazole carbamate) was tested in sheep against standardised strains of Hcaemonchus contortus and Trichostrongylus colubriformis, known to be resistant to thiabendazole (LD90 for thiabendazole against H ontortus was 200 mg/kg bodyweight and against T colubriformis was 150 mg/kg). Fenbendazole at dose rates of 5, 10 and 20 mg/kg per os reduced total worm counts in H contortus infected sheep by 66, 90 and 100 per cent respectively, with similar reductions recorded for worm egg outputs. For the thiabendazole resistant strain of T colubriformis, fenbendazole reduced total worm counts in infected sheep by 4, 44 (40-48), 79 (75-83), 96 and 100 per cent at dose rates of 5, 10, 20, 40 and 80 mg/kg per os. Significant suppression of worm-egg production by thiabendazole resistant T colubriformis was obtained with fenbendazole at dose levels of 5 mg/kg and above. The implications of these results are discussed in the light of the increasing occurrence of strains of trichostrongylid nematodes resistant to currently available benzimidazole anthelmintics.


Assuntos
Hemoncose/veterinária , Doenças dos Ovinos/tratamento farmacológico , Tiabendazol/uso terapêutico , Tricostrongiloidíase/veterinária , Tricostrongilose/veterinária , Animais , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Fezes/parasitologia , Hemoncose/tratamento farmacológico , Hemoncose/parasitologia , Masculino , Ovinos , Doenças dos Ovinos/parasitologia , Tricostrongilose/tratamento farmacológico , Tricostrongilose/parasitologia
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