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91.
Net requirements of calcium, magnesium, sodium, phosphorus, and potassium for growth of Nellore × Red Angus bulls, steers, and heifers 总被引:1,自引:0,他引:1
Mario Luiz Chizzotti Sebastio de Campos Valadares Filho Luis Orlindo Tedeschi Pedro Veiga Rodrigues Paulino Mrio Fonseca Paulino Rilene Ferreira Diniz Valadares Paloma Amaral Pedro Del Bianco Benedeti Tainnah Ikegami Rodrigues Mozart Alves Fonseca 《Livestock Science》2009,124(1-3):242-247
A comparative slaughter trial was conducted to assess the net requirements for gain of Ca, P, Na, K and Mg of bulls, steers and heifers of Nellore and Red Angus crossbreds. Twenty seven F1 Nellore and Red Angus crossbred calves (9 steers, 9 bulls, and 9 heifers), averaging 274 kg BW, were used. At the beginning of the trial, three animals from each gender were slaughtered to determine the initial body composition. The remaining 18 animals (3 animals of each gender) were randomly assigned to two treatments: fed 0.75 or 1.5% of BW of concentrate. The diets were based on corn silage and were isonitrogenous (2% N, DM). After three growing periods of 28 d, all animals were slaughtered. The cleaned gastrointestinal tract, organs, carcass, head, hide, tail, feet, and tissues were weighed to determine the empty BW (EBW). These parts were ground separately and subsampled for chemical analyses. The log of the contents of each mineral in the empty body was regressed on the log of the EBW to estimate the net requirement for each mineral per kg of empty body gain (EBG). There were no differences (P > 0.05) in the net requirements for growth of all macrominerals among genders. The equations of the pooled data of the net requirements for growth (g/kg EBG) were: 332.6 × EBW − 0.6367 for Ca, 112.1 × EBW − 0.5615 for P, 10.85 × EBW − 0.3992 for Na, 4.01 × EBW − 0.153 for K, and 3.589 × EBW − 0.462 for Mg. Our findings indicated that retained Ca and retained P were poorly related to the retained protein. 相似文献
92.
Garcia JL Navarro IT Biazzono L Freire RL da Silva Guimarães Junior J Cryssafidis AL Bugni FM da Cunha IA Hamada FN Dias RC 《Veterinary parasitology》2007,145(3-4):197-206
This study evaluated a vaccine made from crude rhoptry proteins of Toxoplasma gondii with Quil-A, which was administered to cats by the intranasal route. Eleven short-hair domestic cats were divided into four groups: G1 (n=3) received three doses (200 microg/dose) of the rhoptry vaccine with Quil-A (20 microg); G2 (n=3) received PBS with Quil-A (20 microg); G3 (n=3) and G4 (n=2) received only PBS. Treatments were administered at days 0, 21, and 42 by the intranasal route. Challenge was done to G1, G2, and G3 animals with 600 cysts of the VEG strain on day 51 (challenge day); G4 animals were unchallenged. The anti-T. gondii IgG and IgA antibody levels from sera were measured by indirect enzyme-linked immunosorbent assay (ELISA). At challenge, two animals from G1 revealed antibody levels for both IgG and IgA; oocysts were not detected in feces of these two cats. There were no differences in hematological values between groups throughout the experiment (p>0.10). Preventable fractions were 67% in G1 and 0% in G2 and G3. Comparatively, G1 animals shed 89.3% and 90.8% less oocysts than G3 and G4, respectively. Two out of three cats were protected against T. gondii oocyst shedding when the rhoptry vaccine was administered by the intranasal route. This is the first study using crude rhoptry proteins as vaccine by the intranasal route in cats to evaluate protection against oocysts shedding. 相似文献
93.
94.
Milena W. Ferreira Felipe G. de Araujo Diego V. Costa Priscila V. Rosa Henrique C. P. Figueiredo Luis D. S. Murgas 《Journal of the World Aquaculture Society》2011,42(1):24-33
To investigate the impact of different dietary lipid sources on fillet composition and lipid transport, we conducted a feeding trial and evaluated the proximate composition of muscle tissue, fatty acid profiles, total cholesterol (in muscle and plasma), triglycerides, and lipoprotein concentrations in Nile tilapia, Oreochromis niloticus. Five semi‐purified diets, containing different oils (soybean – SO, corn – CO, linseed – LO, fish – FO, and olive – OO), were supplied to tilapia for 160 d. Fish fed with LO and FO diets had a lower percentage of total lipids in muscle compared with the others (P < 0.05). The highest percentage of protein was found in fish fed with FO diet (P < 0.05). The muscle fatty acid profile was influenced differently by diets (P < 0.05). The group supplemented with SO and CO had a higher concentration of 18:2n‐6, whereas the fish fed with LO diet had a higher level of 18:3n‐3 and those that received the FO diet had more 22:6n‐3 in comparison with those supplemented with vegetable oils. Plasma lipid transport was also affected by the diets: the fish fed with FO diet had higher total cholesterol and high‐density lipoprotein and lower very‐low‐density lipoprotein concentrations (P < 0.05). 相似文献
95.
Casado FJ Sánchez AH De Castro A Rejano L Beato VM Montaño A 《Journal of agricultural and food chemistry》2011,59(6):2403-2409
Chemical and sensorial changes related to the use of benzoates and ascorbic acid as additives in packed fermented vegetables were investigated. For this, three selected vegetables (green olives, cucumbers, and caperberries) stored under different conditions (glass or plastic containers, ambient or refrigerated storage) were used. In all cases, benzoic acid remained unchanged (glass bottle) or decreased slightly (plastic pouch) at prolonged storage. Ascorbic acid was partially or totally degraded during storage, the degradation rate depending on the storage conditions and the vegetable matrix. Benzene levels higher than 10 μg/L were found in cucumbers and caperberries containing both additives, but only when packed in plastic pouches and after prolonged storage at room temperature. In these conditions, an appreciable browning of brine, related to AA degradation, was also found. The use of benzoate alone had a significant influence on vegetable color, but flavor was not significantly affected at the benzoate levels tested. On the basis of the present study, benzoates should be removed from fermented vegetable formulations containing ascorbic acid to eliminate possible benzene formation during long-term storage. 相似文献
96.
Christie JL Hewson CJ Riley CB McNiven MA Dohoo IR Bate LA 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(3):250-252
An equine abuse policy was developed as an adjunct to an equine management survey. If at least 3 of 5 categories caused concern, a report to the authorities was indicated. The policy was not used but, in the absence of other guidelines, it might assist veterinarians considering potential abuse cases. 相似文献
97.
Carlos?Wildt Oriol?Gibert José?Luis?CortinaEmail author Giuliana?Coscera 《Journal of Soils and Sediments》2004,4(3):184-191
Goal, Scope and Background The remediation of heavy-metalcontaminated soils and sediments is of significant value to industrial areas around the world.
The spread of such pollutants can result in a potential risk of entering the groundwater system and being transported to potential
receptors. Leaching techniques can be an effective treatment option for the metal removal from soils and sediments. This approach
consists of washing or leaching the contaminated soil with an appropriate reagent and the subsequent treatment of the leaching
in an above-ground installation (on-site treatment) where metals can be removed and concentrated into a smaller volume. Among
the heavy metals, chromium is a commonly identified soil contaminant, particularly in sites with intensive economic activities
including agriculture, industrial, mining and mineral,processing.
Objective The objective of this work was the evaluation and development of a leaching process for the remediation of soils and sediments
polluted with chromium at laboratory scale. Chromium soil pollution was generated after the breakdown of a channel containing
chromium wastes from a tannery plant. The pollution extension has been estimated to be on the order of thousands of tonnes
of soil to be treated, with chromium contents ranging from 500 to 17,000 mg kg-1 soil.
Methods The whole process investigated in this study integrates three stages; a) chromium leaching from a sediment using a diluted
sulphuric acid solution, b) treatment of the leaching effluents with a magnesium oxide/limestone mixture for the precipitation
of chromium hydroxide after acidity neutralisation, and c) polishing step to remove the eventual remaining chromium by adsorption
onto natural zeolite. The amount of contaminated sediment treated ranged from 0.5 to 2 kg with chromium contents of between
2000 and 17,000 mg kg-1.
Results and Discussion The paper describes results on the performance of the process and the optimisation of steps including influence of acid sulphuric
concentration, chromium removal efficiency as well as alkaline reactive mixture proportions. Effluents from the leaching cells
showed a significant decay on the chromium concentration with the increase of leaching runs and a high content of acidity
(pH values close to 0.5). The treatment of these effluents in a second cell containing magnesium oxide/ limestone mixtures
resulted in a high efficiency in neutralisation of acidity (pH values around 7) and chromium removal (concentrations below
5 mg 1-1). The passage through a third compartment containing zeolite as an adsorbent decreased the chromium concentration below 0.5
mg 1-1,
Conclusions From the results obtained on the chromium leaching and immobilisation with magnesium oxide/limestone mixture at a laboratory
scale, it could be pointed out that: (a) diluted sulphuric acid solutions (3%) demonstrated a high efficiency on chromium
removal from sandy polluted soils on the kilogram scale, (b) mixtures of magnesium oxide/limestone demonstrated a high capacity
to neutralise the residual high acidity present on the effluents and to remove chromium by precipitation and (c) between the
limestone and caustic magnesia mixtures, those containing more than 60% of caustic magnesia provide the higher efficiency.
Recommendation and Outlook Future work would be directed to the evaluation of the integrated process of leaching and chromium precipitation on column
at a scale of 100 to 1000 kg. 相似文献
98.
Juan B Barron LJ Ferragut V Guamis B Trujillo AJ 《Journal of agricultural and food chemistry》2007,55(3):747-754
The effect of high-pressure (HP) treatment (300 MPa, 10 min) on the volatile profile of semihard ewe milk cheeses was investigated. The HP treatment was applied at two different stages of ripening (1 and 15 days; 3P1 and 3P15) and microbiota, proteolysis indexes (soluble nitrogen and total free amino acid content), and volatile compounds were assayed at 15, 60, 90, and 150 days of ripening. The intensity of odor and aroma of cheeses was also assayed. 3P1 cheeses presented the highest content of free amino acids and were characterized by the lowest amounts of aldehydes, ketones, short-chain free fatty acids, and terpenes and higher levels of ethanol and ethyl esters. 3P15 cheeses were characterized by the highest content of short-chain free fatty acids and pyruvaldehyde and the lowest abundance of secondary alcohols and were more similar to control cheeses than those HP-treated on the first day. Intensities of odor and aroma were not significantly influenced by the HP treatment. However, the panellists found some differences in 3P1 as compared with control and 3P15 cheeses in what they perceived as lower odor and aroma quality. 相似文献
99.
Luis M. González Alex Aguilar Luis F. López-Jurado Esteve Grau 《Biological conservation》1997,80(3):225-233
The current geographical distribution of the Mediterranean monk seal Monachus monachus colony inhabiting the Cabo Blanco peninsula (Western Sahara-Mauritania) is described. Its distribution range has apparently not changed since surveys conducted in 1984–1988. Sightings of adults on the Tarf el Guerguerat coast, 20 km north of the known breeding caves, suggests the existence of other possible breeding groups further north. Two caves used by the seals are described for the first time. A review of historical trends in cave occupation by seals made it possible (1) to locate the so-called ‘maternity cave’, last reported in 1949; and (2) to establish that the colony, since its discovery, has occupied at least eight caves, five of which have collapsed. An index of population size based on counts of individuals of identified morphological types indicates that, during 1993–1994, the colony was composed of c.113–165 individuals (excluding pups), a larger number than previously assumed. Counting of seals at times of maximum haul-out is proposed as a tool to monitor population trends, although it is considered unreliable for estimating absolute numbers. 相似文献
100.
Performance of a photo‐heterotrophic,hypersaline system for intensive cultivation of white leg shrimp (Litopenaeus vannamei) with minimal water replacement in lined ponds using a stochastic approach 下载免费PDF全文
Luis Daniel Moreno‐Figueroa José Naranjo‐Páramo Alfredo Hernández‐Llamas Mayra Vargas‐Mendieta José Andrés Hernández‐Gurrola Humberto Villarreal‐Colmenares 《Aquaculture Research》2018,49(1):57-67
The aim of the study was to evaluate the performance of Litopenaeus vannamei in an intensive photo‐heterotrophic hypersaline system with minimal seawater replacement, and establish relationships between parameters of a stochastic production model and relevant water quality variables. Six experimental 1000 m2 lined ponds were stocked at a density of 120 shrimp m?2 for a 105‐day trial. Salinity increased from 37 to 45 ± 2 g/L, and the water level was maintained with the weekly addition of filtered seawater, equivalent to 1.6% per day. The stochastic model predicted that, at harvest, there is 95% confidence that the system produces between 12.1 and 14.7 t/ha with a mean final individual weight of 13.1 g and a mean survival of 84.2%. Sensitivity analyses showed that dissolved oxygen and individual final weight of shrimp were the main variables influencing yield variance. Nitrogenous compounds were maintained between optimal cultivation levels (NH3–NH4+ = 0.73 ± 0.43 mg/L, N–NO2? = 0.09 ± 0.05 mg/L, N–NO3? = 3.22 ± 0.11 mg/L). Heterotrophic bacteria (6.6 ± 3.4 × 105 CFU/ml) and chlorophyll‐α concentration (108.5 ± 80.2 μg/L) showed a similar development pattern, indicating a strong relationship between bacteria and microalgae during cultivation. Vibrio spp. concentrations were low (1.24 ± 1.42 × 103 CFU/ml). It was shown that the photo‐heterotrophic system could be used in hypersaline conditions, typical of semi‐arid regions, to consistently produce between 12.1 and 14.7 t/ha in 15 weeks. 相似文献