808 research outputs found

    Ramon (\u3ci\u3eBrosimun alicastrum\u3c/i\u3e) Foliage as Supplement for Lactating Dual Purpose Cows

    Get PDF
    The objective of the present study was to asses the value of ramón (Brosimun alicastrum) foliage as a N-source in replacement of soybean-N in lactating dual purpose cows (Bos indicus x B. taurus). Four lactating cows were used in a latin rectangle design. Ramón was included to replace 0, 33, 66 and 100 % of the soybean-N contained in the supplement. Basal diet was fresh “Taiwán” a cultivar of Elephant grass (Pennisetum purpureum) fed ad libitum. Basal and total dry matter intake, digestibility (total fecal collection), saleable and calf suckled milk yields, and milk composition (fat, protein and lactose) were measured over 15 d periods. Ramon increased the yield of milk constituents (P\u3c 0.05) over those obtained with Taiwán-grass alone, but was inferior (P\u3c 0.05) when soybean was the N source. Total milk yield was reduced 18% in Ramón supplemented cows compared with those supplemented with soybean. Digestibility of dry matter, organic matter and fiber was reduced by Ramón inclusion probably due to its higher fiber and ash content as compared with soybean meal. It was concluded that, although animal performance was not achieved as with soybean meal, supplementing with Ramón is a better strategy than relying on grass alone

    Leucaena leucocephala in ruminant nutrition

    Get PDF
    It is a common situation in extensive ruminant production systems in tropical countries to have low production indicators due to nutrient deficiencies in the diet. An economic alternative to increase animal production is the incorporation of legumes (fodder and fruits) in the diet. This review, presents an analysis of the positive and negative effects of Leucaena leucocephala consumption by ruminants, with particular emphasis on the secondary compound mimosine. Leucaena due to its high nutrient content, rumen by-pass protein supply and its possible effect on the reduction of greenhouse gas (attributed to tannins) has become one of the legumes most commonly used in ruminant feeding practices. However, in countries where leucaena has been introduced, its use is still limited to levels below 30% inclusion in the diet, due to the secondary compound mimosine and its isomers (3,4 and 2,3 DHP), which can induce toxicity, even when animals are inoculated with rumen fluid containing the bacteria Synergistes jonesii reported as responsible for degrading these compounds in the rumen. In the Yucatan Peninsula, Mexico, ruminants consuming leucaena can tolerate more than 50% inclusion in the diet, without having a negative impact on production, attributed intake to mimosine and its isomers. We conclude that in animals not adapted, the intake would be limited to low inclusion levels (less than 30% inclusion in the diet), mainly because of mimosine and its derivatives. The decrease in intake or diet digestibility seem to better explain the reduction in methane production, however, in vivo studies are required to clearly establish the mechanism of action. It has been reported the presence of different bacteria to S. jonessi that would have the ability to degrade mimosine and its derivatives, however, the activity of these bacteria and its effectiveness must be confirmed in vivo

    Digestibility of Duddingtonia flagrans chlamydospores in ruminants: in vitro and in vivo studies

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The use of <it>Duddingtonia flagrans </it>as a tool for the biological control of gastrointestinal nematodes (GIN) is a promising alternative to anthelmintics. The chlamydospores of <it>D. flagrans </it>are orally dosed and their thick cell wall gives them the capacity to resist digestion and pass through the gastrointestinal tract (GIT). Chlamydospores reaching the faeces are able to germinate and trap nematode larvae. The efficacy of this control method is based on reducing the numbers of infective larvae leaving the faeces. Techniques have recently been developed for quantifying the numbers of chlamydospores in faeces. As the number of non-digested spores could be relevant in the design and optimization of dosing programmes for the control of GIN infective larvae, the aim of the present study was to estimate the loss of <it>D. flagrans </it>chlamydospores during their passage through the ruminant gastrointestinal tract using <it>in vitro </it>and <it>in vivo </it>techniques.</p> <p>Results</p> <p>After <it>in vitro </it>rumen digestion, chlamydospore recovery was not different from the quantity originally incubated (undigested spores) (P > 0.05). <it>In vitro </it>rumen+abomasum digestion caused nearly 36% loss of the chlamydospores originally incubated (P < 0.05). Germination of chlamydospores classified as viable was 24.3%. Chlamydospores classified as non-viable did not germinate. Rumen digestion resulted in more spore germination (R1 = 35.7% and R2 = 53.3%) compared to no digestion (time 0 h = 8.7%). Subsequent abomasal digestion reduced germination (R1+A = 25%) or stopped it (R2+A = 0%). <it>In vivo </it>apparent chlamydospore digestibility in sheep showed a loss of 89.7% of the chlamydospores (P < 0.05).</p> <p>Conclusions</p> <p>The loss of chlamydospores was evident under <it>in vitro </it>and <it>in vivo </it>conditions. Negligible amounts of spores were lost during the <it>in vitro </it>rumen digestion. However, <it>in vitro </it>rumen+abomasum digestion resulted in a chlamydospore loss of approximately 36%. <it>In vivo </it>passage through the sheep GIT resulted in a total loss of 89.7% of the orally administered spores.</p

    Weeds Forage Potential for Ruminant Feeding: Chemical Composition and Kinetics of Rumen Degradation

    Get PDF
    Systems of ruminant production in the Andean highlands of Ecuador are dominated by monoculture grasses, where producers do not allow association with other plants such as weeds. These systems have small areas of land and the peasants would be wasting feed resources (association) with high nutritional content and secondary compounds that may be beneficial for feeding ruminants improving the nutritional value of grassland. In this context, CastelĂĄn et al. (2003) mention that the use of weeds in ruminant nutrition by small producers in temperate areas of Mexico, it becomes the main natural forage resource for livestock to feed round the year, as there great availability. For farmers with limited financial resources this practice is very common, because it represents feeding efficiency with low production costs, because they use non-conventional feed resources. Weed species such as Sicyos deppei G., Jaltomata procumbens (Cav.), Drymaria laxiflora Benth y Lopezia racemosa Cav. contain high levels of ruminal fermentation and high crude protein content, as well as low levels of fiber (CastelĂĄn et al., 2003). Under this background, the objective of this research is to determine the chemical composition and in situ ruminal degradation of weeds with forage potential that exist in the grasslands of the Andean highlands of Ecuador

    Is there a negative association between the content of condensed tannins, total phenols, and total tannins of tropical plant extracts and in vitro anthelmintic activity against Haemonchus contortus eggs?

    Get PDF
    In vitro studies using plant extracts suggest a relationship between their polyphenol contents and their anthelmintic (AH) activity against Haemonchus contortus. High polyphenol content appears to increase the efficacy of plant extracts against H. contortus as assessed by the larval exsheathment inhibition assay (LEIA) while appearing to reduce the AH efficacy measured using the egg hatch assay (EHA). In addition, some plants lack AH activity. Therefore, the present study investigated the relationship between the contents of condensed tannins (CT), total phenols (TP), and total tannins (TT) in methanol:water extracts (70:30) obtained from ten tropical plant species consumed by small ruminants as well as their AH activity against H. contortus evaluated by LEIA and EHA. Extracts of Acacia collinsii, Lysiloma latisiliquum, Havardia albicans, Senegalia gaumeri, Mimosa bahamensis, Piscidia piscipula, Acacia pennatula, Gymnopodium floribundum, Leucaena leucocephala, and Bunchosia swartziana were examined. Positive correlations were found between the effective concentration 50% (EC50) (EHA) of extracts and their CT (r = 0.6809, P < 0.05, n = 10) and TP (r = 0.9152, P < 0.05, n = 10) content, suggesting that their concentration negatively affected AH activity against eggs. Based on the LEIA, there was no significant association between the EC50 and the CT, TP, or TT of all extracts evaluated. Thus, if sheep and goats consume a complex feed mixture with high amounts of CT, TP, and TT, it might be difficult to observe an AH effect against H. contortus egg hatching. However, the AH effect upon L3 establishment might be feasible

    Age of Haemonchus contortus third stage infective larvae is a factor influencing the in vitro assessment of anthelmintic properties of tannin containing plant extracts

    Get PDF
    The larval exsheathment inhibition assay (LEIA) of infective larvae (L3) is an in vitro method used to evaluate the anthelmintic (AH) activity of tannin-containing plant extracts against different species of gastrointestinal nematodes, including Haemonchus contortus. Some conditions remain to be defined in order to standardize the LEIA, i.e. the optimal age of larvae produced from donor animals to use in the assays. Therefore, this study aimed at identifying the effect of age and age-related vitality of H. contortus infective larvae produced under tropical conditions, on the in vitro AH activity measured with the LEIA. The same acetone:water (70:30) extract from Acacia pennatula leaves was used to perform respective LEIA tests with H. contortus L3 of different ages (1–7 weeks). Each week, the L3 were tested against different concentrations of extract (1200, 600, 400, 200, 100, 40μg/mL of extract) plus a PBS control. Bioassays were performed with a benzimidazole (Bz) resistant H. contortus (Paraíso) strain. In order to identify changes in L3 vitality on different weeks (1–7), two assays testing larval motility were included only with PBS: the larval migration assay (LMA) and the larval motility observation assay (LMOA). Mean effective concentrations causing 50% and 90% exsheathment inhibition (EC50, EC90) were obtained for every week using respective Probit analyses. On the first week, the larvae had lowest EC50 and EC90 (39.4 and 65.6μg/mL) compared to older larvae (P0.05), while older larvae tended to show higher EC50 and EC90 (P<0.05). Motility showed strong negative correlations with age of larvae (r≥−0.83; P <0.05) and EC50 (r≥−0.80; P<0.05), suggesting that the lower extract efficacy could be associated with decaying vitality of larvae associated with age. More stable efficacy results were found between two to five weeks of age

    An in vitro approach to evaluate the nutraceutical value of plant foliage against Haemonchus contortus

    Get PDF
    Nutraceutical plants provide nutrients for the animal as well as secondary compounds that can affect the biology and survival of gastrointestinal nematodes (GIN). Current screening of nutraceutical plants is based on in vitro evidence of anthelmintic (AH) activity against different life stages of GIN, but nutritional information is omitted or scarce. This study proposes an integral in vitro screening protocol to identify the nutraceutical value of the foliage from plant species consumed by small ruminants, using Haemonchus contortus as a biological model. The leaves from Acacia collinsii, A. pennatula, Bunchosia swartziana, Gymnopodium floribundum, Havardia albicans, Leucaena leucocephala, Lysiloma latisiliquum, Mimosa bahamensis, Piscidia piscipula, and Senegalia gaumeri were evaluated for their chemical composition and in vitro digestibility. Acetone:water extracts (70:30) from leaves of each plant were evaluated using the egg hatch assay and larval exsheathment inhibition assay. Respective effective concentrations 50% (EC50) were determined for each assay. The ten plant species showed good nutritional value for ruminants, including crude protein (> 10%), metabolizable energy (> 2.9 MJ/kg DM), and varied CT content (from 1.0 to 37.6%). The best AH activity against H. contortus eggs (EC50 = 401.8 μg/mL) and L3 (EC50 = 83.1 μg/mL) was observed for S. gaumeri extract. Although all the plant species showed in vitro nutraceutical potential, the leaves of S. gaumeri had the best values. The proposed in vitro protocol showed to be useful for the integral assessment of the nutraceutical potential of different plant species as it included the nutritional value and the AH activity against eggs and L3 in the selected plant species

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
    • …
    corecore