scholarly journals Composición nutricional de tres pastos colectados en el estado de Morelos, México

2021 ◽  
Vol 8 (II) ◽  
Author(s):  
Eliseo Sosa-Montes ◽  
Sergio Iban Mendoza-Pedroza ◽  
Andrés Ramos-Velázquez ◽  
Perpetuo Alvarez- Vázquez ◽  
Eusebio Ortega- Jiménez ◽  
...  

El objetivo de este estudio fue evaluar tres pastos forrajeros, Bromus diandrus, Oplismenus burmannii y Heteropogon contortus, de las subfamilias Pooideae, Pooideae y Panicoideae, respectivamente. Las principales variables respuesta, todas en base seca fueron: cenizas (Cen), proteína cruda (PC), extracto etéreo (EE), carbohidratos solubles (CS), fibra detergente neutro (FDN), contenido celular (CC = 100 - FDN) y digestibilidad in vitro de la materia seca (DIVMS). Cada pasto se evaluó por triplicado y una repetición se consideró la unidad experimental. Las medias fueron separadas mediante la prueba de Tukey (p < 0.05). La asociación entre cada par de variables (p < 0.05) se estimó usando el coeficiente de correlación de Pearson (p < 0.05). Los pastos B. diandrus y O. burmannii resultaron con más PC, CC y DIVMS y con menos pared celular o FDN (componente insoluble) que H. contortus. Esto produjo una correlación positiva entre CC y PC (0.751, p < 0.05). Adicionalmente, O. burmannii produjo el valor más alto de Cen y el más bajo de CS, mientras que B. diandrus mostró el valor más bajo de Cen y el más alto de CS. Esto produjo una correlación negativa entre estas dos variables (-0.976, p < 0.01). En conclusión, B. diandrus, mostró mejor composición química y digestibilidad, que los otros dos, por lo que se recomienda este pasto para la nutrición de rumiantes. 

1972 ◽  
Vol 25 (6) ◽  
pp. 1377 ◽  
Author(s):  
RFH Dekker ◽  
GN Richards

The dry matter digestibility (DMD) of poor quality roughages such as spear grass (Heteropogon contortus) by sheep and cattle has been shown to increase on addition of sulphur to the diet. The sulphur is added most frequently as inorganic sulphate, either alone (Playne 1969) or supplemented with urea (Bray and Hemsley 1969; Kennedy and Siebert 1972; Siebert and Kennedy 1972) or gluten (Playne 1969). These supplements have also increased feed intake in sheep (Playne 1969; Kennedy and Siebert 1972; Siebert and Kennedy 1972) and cattle (Siebert and Kennedy 1972), and have improved the nitrogen and sulphur balance (Moir, Somers, and Bray 1967; Bray and Hemsley 1969; Playne 1969; Kennedy and Siebert 1972) within the animal. Sulphates have been shown to increase the in vitro rumen digestion of starch (Kennedy, Mitchell, and Little 1971), crude fibre (Bray and Hemsley 1969), and acid-detergent fibre and cellulose (Barton, Bull, and Hemken 1971).


1981 ◽  
Vol 21 (113) ◽  
pp. 600 ◽  
Author(s):  
JG McIvor

The growth of unfertilized native pasture was studied at two sites (Lansdown near Townsville and Redlands near Charters Towers) over a 30-month period. Seasonal changes in the dry matter distribution between green leaf, green stem, dry leaf, dry stem and inflorescence, and the nitrogen and phosphorus concentrations and in vitro digestibility of these components were measured in Chrysopogon fallax, Heteropogon contortus and Themeda australis. Maximum herbage yields ranged from 4000-6000 kg/ha at Lansdown and 1500-2000 kg/ha at Redlands with perennial grasses contributing over 90% of the herbage. There were large differences between the species in the pattern of dry matter distribution, with C. fallax having a higher proportion of leaf during most of the sampling period. The nitrogen and phosphorus concentrations and digestibility levels in the various plant components were usually similar in the three grasses but all showed large seasonal variations at both sites. Green leaf was the most nutritious component but even this was of too low a quality to support animal growth during part of the year.


2018 ◽  
Vol 8 (2) ◽  
pp. 65
Author(s):  
W. D. Ratnasooriya ◽  
R. N. Pathirana ◽  
R. N. N. Gamage ◽  
K. B. Hasanthi ◽  
S. K. Hettihewa

Author(s):  
P.L. Moore

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.


Author(s):  
John J. Wolosewick ◽  
John H. D. Bryan

Early in spermiogenesis the manchette is rapidly assembled in a distal direction from the nuclear-ring-densities. The association of vesicles of smooth endoplasmic reticulum (SER) and the manchette microtubules (MTS) has been reported. In the mouse, osmophilic densities at the distal ends of the manchette are the organizing centers (MTOCS), and are associated with the SER. Rapid MT assembly and the lack of rough ER suggests that there is an existing pool of MT protein. Colcemid potentiates the reaction of vinblastine with tubulin and was used in this investigation to detect this protein.


Author(s):  
E. J. Kollar

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.


Author(s):  
M. Kraemer ◽  
J. Foucrier ◽  
J. Vassy ◽  
M.T. Chalumeau

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.


Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.


Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.


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