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1.
J Anim Sci ; 95(10): 4413-4420, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29108046

RESUMO

A 2-yr grazing trial was conducted to evaluate the use of conserved forage type, stockpiled Tifton 85 bermudagrass ( L.; T85) or T85 hay, and supplement type for stocker cattle during the fall forage deficit in the southeastern United States. The study site consisted of six 0.75-ha paddocks of stockpiled T85 for grazing and six 0.20-ha drylot paddocks for feeding T85 hay. Steers ( = 5 per paddock; mean initial BW for both yr, 263 ± 30 kg) were randomly assigned to paddocks on November 11, 2014 and October 28, 2015 in yr 1 and yr 2, respectively. Treatments included T85 hay or stockpile (control), T85 hay or stockpile plus 0.2 kg cottonseed meal and 0.7 kg soybean hulls∙steer∙d (SUPPL1), or 0.45 kg cottonseed meal and 0.45 kg soybean hulls∙steer∙d (SUPPL2). Polytape fencing was used for frontal grazing stockpiled T85 paddocks to allocate a 3- to 4-d allotment of forage DM for the animals based on available forage mass and steer DMI requirements. There were no differences among treatments ( > 0.10) in mean pregrazing forage mass across sampling dates (5,099 kg DM/ha and 7,998 kg DM/ha in yr 1 and yr 2, respectively), forage allowance (1.9 kg DM/kg steer BW and 3.0 kg DM/kg steer BW in yr 1 and yr 2, respectively) and forage utilization (84% and 88% in yr 1 and yr 2, respectively). No differences ( > 0.10) were detected for nutritive value parameters CP, ADF, NDF, and TDN among stockpiled T85 treatments in both yr. However, there were differences across sampling dates ( < 0.0001) for stockpiled T85 such that forage quality generally declined as the grazing season progressed in both yr. Steers fed T85 hay had greater final BW and ADG ( = 0.018) than those grazing stockpiled T85. Mean final BW and ADG of steers grazing T85 stockpile or fed hay with no supplementation was less ( = 0.020) than those receiving supplementation. Steers grazing stockpiled T85 had decreased ADG in the second half of the grazing season in both yr of the study, which is a result of declining forage nutritive value as the stockpiling season progressed. Results indicate that stockpiled T85 supplemented with CP and energy can support stocker cattle at a maintenance level, but to achieve a target gain of 0.9 kg/day would require a greater level of supplementation to overcome decreasing forage nutritive value dynamics.


Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Cynodon , Fibras na Dieta/análise , Suplementos Nutricionais , Animais , Bovinos/crescimento & desenvolvimento , Masculino , Valor Nutritivo , Distribuição Aleatória , Estações do Ano , Glycine max
2.
Transl Anim Sci ; 1(4): 592-598, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32704681

RESUMO

Two experiments were conducted to evaluate 3 silage-based stocker diets. In Exp. 1, diets were fed to a total of 276 animals over a period of 3 yr and performance data was collected. In Exp. 2, the same diets were subjected to in vitro digestion for 5 time periods: 0, 6, 12, 24, and 48 h, to evaluate IVDMD, production of fermentation end products, and efficiency of transformation of energy. The experimental diets were similar, except for their protein supplements. They were composed of: 1) 74% corn silage, 15.2% ground ear corn, and 10.8% soybean meal (SBM); 2) 74.4% corn silage, 9.8% ground ear corn, and 15.8% canola meal (CAN); 3) 74.5% corn silage, 9.8% ground ear corn, and 15.7% sunflower meal (SUN). Results from Exp. 1 showed that DMI was similar across all treatments (P = 0.167), but ADG was greater (P = 0.007) for animals fed either SBM or CAN than for animals fed SUN (1.29, 1.28, and 1.20 kg/d, respectively). Both CAN and SUN significantly reduced (P < 0.001) daily feeding cost per animal in comparison to SBM. Exp. 2 revealed that total VFA production was similar for all treatments (P = 0.185), and greatest molar proportions of propionate were observed for SBM and CAN (P = 0.02). Additionally, IVDMD was highest for SBM (P < 0.001). Regression analysis showed that most of the evaluated traits followed a quadratic trend for incubation times (P ≤ 0.02). On average, the in vitro technique used in this study was able to account for 97.03% of the caloric transformations suffered by DE throughout the different incubation times. Overall, our findings revealed that although animals receiving SUN had the cheapest daily feeding cost, important traits like ADG and feed conversion rate were negatively affected by this treatment. In contrast, data showed that CAN was an effective replacement for SBM for it maintained similar animal performance while decreasing feed costs. Therefore, from a producer standpoint, CAN is a viable alternative to replace the more costly SBM diet in silage-based stocker operations.

3.
Folia Morphol (Warsz) ; 65(1): 15-21, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16783730

RESUMO

Despite intensive research in the anatomical sciences for the last two centuries, some structures of the human body still remain controversial or incompletely described. We describe a new membranous fascial anatomical entity, which we refer to as the iliolumbar membrane (ILM). During the 2004-2005 academic semesters at the American University of the Caribbean School of Medicine we dissected 40 human cadavers fixed in formalin-alcohol-phenol solution. Iliolumbar membrane is a thick connective tissue structure, deep to the skin, originating from the fibres of the thoracolumbar fascia at the lateral border of the erector spinae. It runs inferior to the superior border of the iliac crest, lateral to the posterior superior iliac spine, overlying the iliac crest at the level of the 4th lumbar vertebra. Iliolumbar membrane terminates within subcutaneous fat, where it divides into multiple layers. All cadavers showed considerable variation in the blending of the membrane's multiple layers with the subcutaneous fat. However, all specimens consistently showed a uniform appearance of ILM at the point of origin. Iliolumbar membrane could be demonstrated objectively by ultrasound examination with a frequency of 7.5 MHz and also with a Stryker endoscope. A hypothesis is put forth, conjecturing that this new structure may have relevance in creating a natural barrier between the musculature of the back and the muscles of the gluteal region, similar to Scarpa's fascia of the anterior abdominal wall.


Assuntos
Dorso/anatomia & histologia , Ílio/anatomia & histologia , Ligamentos Articulares/anatomia & histologia , Vértebras Lombares/anatomia & histologia , Membranas/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Dorso/diagnóstico por imagem , Cadáver , Fáscia/anatomia & histologia , Fáscia/diagnóstico por imagem , Feminino , Humanos , Ligamentos Articulares/diagnóstico por imagem , Masculino , Membranas/diagnóstico por imagem , Pessoa de Meia-Idade , Ultrassonografia
4.
Arch Surg ; 133(12): 1335-42, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9865652

RESUMO

OBJECTIVE: To determine the endothelial-dependent control of decreased peripheral vascular resistance in skeletal muscle microvessels during evolving sepsis. MATERIALS AND INTERVENTIONS: Acute (4 hours, n=7), established (24 hours, n=7), or chronic (72 hours, n=8) infection was induced in Sprague-Dawley rats (150-175 g) by injecting Escherichia coli and Bacteroides fragilis (1 x 10(9) colony-forming units for both) into a subcutaneous sponge. Control animals were injected with an isotonic sodium chloride solution and analyzed at the same time points: (n=6-8 per group). Dilation in response to the topically applied endothelial-dependent agonist acetylcholine (ACH) (1 x 10(-9) to 1 x 10(-5) mol/L) was measured in inflow first-order (A1) and precapillary fourth-order (A4) arterioles in cremaster muscle in vivo with videomicroscopy. Acetylcholine dose-response curves were used to determine vascular reactivity by calculating the concentration of ACH necessary to elicit 50% of the maximal dilator response. MAIN OUTCOME MEASURES: In vivo reactivity of striated muscle microvessels to the dilation agonist ACH during acute, established, and chronic infection. RESULTS: A1 vessels were unresponsive to all doses of ACH at all time points. A4 vessels showed an increased dilator response during short-term treatment, which deteriorated over time to depressed dilation during chronic infection. CONCLUSIONS: Precapillary A4 vessels have increased dilator reactivity during early sepsis, which progresses to depressed levels with chronic infection. A1 microvessels remain dilated and are not substantially influenced by endothelial dilator mechanisms initiated by ACH. Maximum dilation of the large A1 vessels appears to contribute to the decrease in peripheral vascular resistance noted during systemic infection.


Assuntos
Endotélio Vascular/fisiopatologia , Músculo Esquelético/irrigação sanguínea , Sepse/fisiopatologia , Resistência Vascular/fisiologia , Acetilcolina/farmacologia , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/fisiopatologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Hemodinâmica , Masculino , Nitroprussiato/farmacologia , Ratos , Ratos Sprague-Dawley , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/farmacologia , Vênulas/efeitos dos fármacos , Vênulas/fisiopatologia
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