Effects of feed intake on in situ rumen microbial contamination and degradation of feeds     

C.A. Rodríguez  J. Gonzlez  M.R. Alvir  R. Caballero 《Livestock Science》2008,116(1-3):108-117

An in situ study was conducted using four rumen cannulated wethers and five feeds (corn grain (CG), soybean meal (SBM), sunflower meal (SFM), vetch–oat hay (VH), and lentil straw (LS)) to determine (using ¹⁵N infusion techniques) the effects of two intake levels (40 and 80 g DM/kg W^0.75) on the microbial contamination and rumen degradation of DM or CP. Degradation studies were also performed for neutral and acid detergent fibres (NDF and ADF, respectively) of VH. In most cases, the evolution with time of the microbial DM adhered to particles fitted well to exponential curves, which diverged between both levels of intake due to the lower values attained at high intake. However, as a consequence of the large and progressive increase of the variability of microbial contamination, statistical evidence is only partial. This behaviour was less evident for CP contamination, especially in forages. The lack of these corrections underestimated (P < 0.001) the effective degradability (ED) of all tested fractions, with important differences between feeds. The intake level had not relevant effects on the distribution of soluble, insoluble available and unavailable fractions of DM or CP (or fibres in VH), but determined some changes in their degradation rates (k_d). Direct relations between these last values and rumen outflow rates (k_p) were shown in some feeds for the degradation of CP and also of DM in concentrates, whereas negative relations were shown for the degradation rates of DM in forages (or NDF and ADF of VH). All ED estimates decreased with the intake rise, but for CP this effect (P < 0.05) was only detected in SBM and VH. These decreases represent 40.8 (CG), 80.8 (SBM), 62.1 (SFM), 66.8 (VH), and 19.5% (LS) than those estimated considering only k_p changes, which shows the interest to consider conjointly the variations of both rates to study the effect of diet changes on ED.  相似文献   

7500 years of prehistoric footwear from arnold research cave, missouri     

JT Kuttruff  SG DeHart  MJ O'Brien 《Science (New York, N.Y.)》1998,281(5373):72-75

Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene.  相似文献   

Genesis and evolution of the 1997-98 El Nino   总被引：4，自引：0，他引：4  

MJ McPhaden 《Science (New York, N.Y.)》1999,283(5404):950-954

The 1997-98 El Nino was, by some measures, the strongest on record, with major climatic impacts felt around the world. A newly completed tropical Pacific atmosphere-ocean observing system documented this El Nino from its rapid onset to its sudden demise in greater detail than was ever before possible. The unprecedented measurements challenge existing theories about El Nino-related climate swings and suggest why climate forecast models underpredicted the strength of the El Nino before its onset.  相似文献   

The importance of dietary HUFA for meagre larvae (Argyrosomus regius; Asso, 1801) and its relation with antioxidant vitamins E and C          下载免费PDF全文

Najlae El Kertaoui  Carmen María Hernández‐Cruz  Daniel Montero  María José Caballero  Reda Saleh  Juan Manuel Afonso  Marisol Izquierdo 《Aquaculture Research》2017,48(2):419-433

Despite the interest of meagre (Argyrosomus regius) as a fast‐growing candidate for Mediterranean aquaculture diversification, there is a lack of information on nutrition along larval development. Importance of highly unsaturated fatty acids (HUFA) and the antioxidant vitamins E and vitamin C has not been investigated yet in this species. Six diets with two levels of HUFA (0.4% and 3% dw), two of vitamin E (1500 and 3000 mg kg^?1) and two of vitamin C (1800 and 3600 mg kg^?1) were fed to 15 dah meagre larvae. Larval growth in total length and dry body weight was significantly lowest in larvae fed diet 0.4/150/180 and showed few lipid droplets in enterocytes and hepatocytes and lower HUFA contents than the initial larvae. Increase in dietary HUFA up to 3%, significantly improved larval growth and lipid absorption and deposition. Besides, among fish fed 3% HUFA, increase in vitamin E and vitamin C significantly improved body weight, as well as total lipid, 22:6n‐3 and n‐3 fatty acids contents in the larvae. Thus, the results showed that 0.4% dietary HUFA is not enough to cover the essential fatty acid requirements of larval meagre and a high HUFA requirement in weaning diets is foreseen for this species. Besides, the results also pointed out the importance of dietary vitamin E and C to protect these essential fatty acids from oxidation, increase their contents in the larvae and promote growth, suggesting high vitamin E and C requirements in meagre larvae (higher than 1500 and 1800 mg kg^?1 for vitamin E and vitamin C respectively).  相似文献   

Development of short-snouted seahorse (<Emphasis Type="Italic">Hippocampus hippocampus</Emphasis>, L. 1758): osteological and morphological aspects     

B. Novelli  F. Otero-Ferrer  J. A. Socorro  M. J. Caballero  A. Segade-Botella  L. Molina Domínguez 《Fish physiology and biochemistry》2017,43(3):833-848

Information about early development after male release lags behind studies of juveniles and adult seahorses, and newborn seahorses, similar in shape to adults, are considered juveniles or fry. During early life, Hippocampus hippocampus present behavioural (shift in habitat, from planktonic to benthic) and morphological changes; for this reasons, the aims of this study are to define the stage of development of H. hippocampus after they are expelled from the male brood pouch and to establish direct or indirect development through an osteological analysis. The ossification process was studied in 120 individuals, from their release to 30 days after birth. To analyse the osteological development, Alcian Blue-Alizarin Red double staining technique for bone and cartilage was adapted to this species. At birth, H. hippocampus presents a mainly cartilaginous structure that ossifies in approximately 1 month. The bony armour composed of bony rings and plates develops in 10 days. The caudal fin, a structure absent in juveniles and adult seahorses, is present at birth and progressively disappears with age. The absence of adult osteological structure in newborns, like coronet, bony rings and plates, head spines and components allowing tail prehensile abilities, suggests a metamorphosis before the juvenile stage. During the indirect development, the metamorphic stage started inside brood pouch and followed outside and leads up to reconsider the status of H. hippocampus newborns.  相似文献   

Stage‐specific insecticidal characteristics of a nucleopolyhedrovirus isolate from Chrysodeixis chalcites enhanced by optical brighteners     

Alexandra Bernal  Oihane Simón  Trevor Williams  Primitivo Caballero 《Pest management science》2014,70(5):798-804

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Genetic diversity for seed storage proteins in Lebanon and Turkey populations of wild diploid wheat (<Emphasis Type="Italic">Triticum urartu</Emphasis> Thum. ex Gandil.)     

L. Caballero  M. A. Martín  J. B. Alvarez 《Genetic Resources and Crop Evolution》2009,56(8):1117-1124

Triticum urartu is a wild diploid wheat identified as donor of the A genome in the durum and bread wheats. This species has its natural distribution zone in the Fertile Crescent. Nine populations from this zone (five Lebanese and four Turkish) were analysed for the variation in the loci coding of endosperm storage proteins: glutenins (Glu-A ^u 1 and Glu-A ^u 3) and gliadins (Gli-A ^u 1 and Gli-A ^u 2). Up to 10 alleles for the Glu-A ^u 1 locus, 16 for the Glu-A ^u 3 locus, 15 for the Gli-A ^u 1 locus and 18 for the Gli-A ^u 2 locus were found. The Turkish populations showed greater diversity than the Lebanese populations, distributing mainly within populations, whereas the inverse process takes place for the Lebanese populations. The values of the genetic diversity indicated that, although these materials showed high level of variability, exist a real risk of genetic erosion.  相似文献   

Multiple abscesses caused by <Emphasis Type="Italic">Salmonella enterica</Emphasis> and <Emphasis Type="Italic">Corynebacterium pseudotuberculosis</Emphasis> in a dromedary camel     

Tejedor-Junco MT  Lupiola P  Caballero MJ  Corbera JA  Gutierrez C 《Tropical animal health and production》2009,41(5):711-714

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Electroencephalographic evaluation of gold wire implants inserted in acupuncture points in dogs with epileptic seizures     

Goiz-Marquez G  Caballero S  Solis H  Rodriguez C  Sumano H 《Research in veterinary science》2009,86(1):152-161

The purpose of this study was to evaluate both, clinically and with electroencephalographic (EEG) recordings, the effect of gold wire implants in acupuncture points in dogs with uncontrolled idiopathic epileptic seizures. Fifteen dogs with such diagnosis were enrolled in the study. A first EEG recording was performed in all dogs under anaesthesia with xylazine (1 mg/kg) and propofol (6 mg/kg) before the treatment protocol, and a second EEG was performed 15 weeks later. Relative frequency power, intrahemispheric coherence available through EEG, number of seizures and seizure severity were compared before and after treatment using a Wilcoxon signed-rank test. There were no significant statistical differences before and after treatment in relative power or in intrahemispheric coherence in the EEG recording. However, there was a significant mean difference in seizure frequency and seizure severity between control and treatment periods. After treatment, nine of the 15 dogs (60%) had at least a 50% reduction in seizures frequency during the 15 weeks established as follow-up of this treatment.  相似文献   

Oxidative status and histological changes in sea bass larvae muscle in response to high dietary content of docosahexaenoic acid DHA     

M B Betancor  M J Caballero  T Benítez‐Santana  R Saleh  J Roo  E Atalah  M Izquierdo 《Journal of fish diseases》2013,36(5):453-465

In previous studies, we observed dystrophic alterations in muscle of 48‐day‐old sea bass fed imbalanced docosahexaenoic acid (DHA) and vitamin E diets. To understand the whole pathological process associated with oxidative stress, a histological study was performed by feeding 14‐day‐old sea bass larvae with microdiets containing different ratios of DHA/vitamin E (1/150, 5/150 and 5/300) for a period of 21 days. Larvae fed diet 1/150 showed no lesions in contrast to larvae fed diets 5/150 and 5/300 where the highest incidence of muscle lesions and thiobarbituric acid reactive substances (TBARS) content was observed. Semithin sections revealed focal lesions consisting of degenerated fibres with hypercontracted myofilaments and extensive sarcoplasm vacuolization affecting both red and white muscle. Ultrathin sections of degenerating muscle fibres showed diffuse dilatation of sarcoplasmic reticulum, disorganized myofilaments and autophagic vacuoles containing myelin figures and dense bodies. Additionally, some macrophages were observed among injured fibres as numerous satellite cells. Results from the study agree with those obtained from previous work, proving the pathological potential of free radicals in sea bass larvae musculature. Moreover, high vitamin E inclusion could not completely protect cell membranes from free radicals action.  相似文献