Relationship between ketosis and dairy cows’ blood metabolites in intensive production farms of the periurban area of Dakar

This study which involved 140 Holstein and Montbeliard was carried out in the periurban area of Dakar with the aim to establish the relationship between ketosis, milk production and biochemical blood metabolites. The results showed that ketosis is a real problem in periurban farms around the city of Dakar with high proportions of 33.57% for subclinical ketosis and 6.43% for clinical ketosis. In their second month of milking, cows with subclinical ketosis had a decrease of 12.4 and 15.,6% in milk yield respectively for Montbeliard and Holstein, whereas cows with clinical ketosis had a decrease of 18.6 and 26%. Ketogenic cows (subclinical and clinical) have significantly lower average levels of blood glucose (p<0.05) and significantly higher average levels of blood urea (p<0.05) than cows with normal blood beta-Hydroxy Butyrate (BbHB) levels. Also, from one farm to another, significant difference was recorded with concentration of total proteins and globulin, calcium and magnesium.     

Spatial variability in ocean‐mediated growth potential is linked to Chinook salmon survival

Early ocean survival of Chinook salmon, Oncorhynchus tshawytscha, varies greatly inter‐annually and may be the period during which later spawning abundance and fishery recruitment are set. Therefore, identifying environmental drivers related to early survival may inform better models for management and sustainability of salmon in a variable environment. With this in mind, our main objectives were to (a) identify regions of high temporal variability in growth potential over a 23‐year time series, (b) determine whether the spatial distribution of growth potential was correlated with observed oceanographic conditions, and (c) determine whether these spatial patterns in growth potential could be used to estimate juvenile salmon survival. We applied this method to the fall run of the Central Valley Chinook salmon population, focusing on the spring and summer period after emigration into central California coastal waters. For the period from 1988 to 2010, juvenile salmon growth potential on the central California continental shelf was described by three spatial patterns. These three patterns were most correlated with upwelling, detrended sea level anomalies, and the strength of onshore/offshore currents, respectively. Using the annual strength of these three patterns, as well as the overall growth potential throughout central California coastal waters, in a generalized linear model we explained 82% of the variation in juvenile salmon survival estimates. We attributed the relationship between growth potential and survival to variability in environmental conditions experienced by juvenile salmon during their first year at sea, as well as potential shifts in predation pressure following out‐migration into coastal waters.     

Nutrient digestibility profile of premium (category III grade) animal protein by-products for temperate marine fish species (European sea bass, gilthead sea bream and turbot)

Three trials, with classical experimental designs for in vivo digestibility studies, were conducted to determine the apparent digestibility coefficient (ADC) of protein (ADCp), lipid (ADCl), energy (ADCe) and amino acids (AA) in selected animal by-products fed to European sea bass, Dicentrarchus labrax (Trial 1), gilthead sea bream, Sparus aurata (Trial 2), and turbot, Psetta maxima (Trial 3). In each trial, five experimental diets [including a reference diet (RD)] where fish meal (FM) was used as the sole protein source were fed ad libitum to the fish for a period of 4 weeks. Test diets were based on the FM RD and obtained by replacing 30% of the RD with a category III designated European animal by-products (fit for human consumption), namely: steam hydrolysed feather meal (HFM), enzyme-treated feather meal (EFM), poultry meat meal (PMM) and spray-dried haemoglobin meal (SDHM). Faecal material was collected using the 'Guelph system', and nutrient and energy digestibility coefficients were related to the measurement of chromic oxide (Cr₂O₃) incorporated into the diet at a rate of 0.5%. Without any exception, FM diets yielded the best digestibility values for all macro-nutrients and by all fish. Among the test ingredients, ADCp was consistently higher for PMM and SDHM in the three species (85.5%, 91.1% in sea bass; 79.2%, 82.8% in sea bream; and 78.4%, 74.8% in turbot). Conversely, ADCp of HFM and EFM were less efficiently digested (67.2%, 68.2% in sea bass; 21.5%, 21.7% in sea bream; and 46.6%, 36.0% in turbot). However, the novel processing method applied to feather meal did not considerably influence the digestibility of most of the nutrients in this feedstuff. The current investigation yielded valuable numerical ADC for EAA considered to be of prime importance in generating balanced diet formulations.     

Gastric absorption of a pesticide (1-naphthyl N-methylcarbamate) in the fasted rat

The gastric absorption of [1-naphthyl-1-¹⁴C]N-methylcarbamate (radiolabeled carbaryl) administered intragastrically (7.5 μmoles/kg body wt) to fasted, anesthetized female rats was investigated by measurement of ¹⁴C absorption and by identification of the radiolabeled constituents in the portal blood. At 22 and 67 min after dosing, 52.6 ± 14.1% (n = 3) and 81.7 ± 15.7% (n = 3), respectively, of the ¹⁴C was absorbed from the stomachs (ligated pylori) of rats with intact portal circulation. In another experiment, 69.1 ± 25.9% (n = 3) of the ¹⁴C was absorbed from the rat stomachs (ligated pylorus and esophagus) during 66.0 ± 1.0 min of total portal blood collection (via an in vivo perfusion technique). The radiolabeled material in the collected portal blood accounted for 97.2 ± 1.9% (n = 3) of the ¹⁴C absorbed from rat stomachs. On the basis of thin-layer chromatography, gas chromatography, and infrared spectroscopy, 89.3% of the radiolabeled material in the collected portal blood was [1-naphthyl-1-¹⁴C]N-methylcarbamate.     

Isolation of nuclei from a marine dinoflagellate

By means of a medium containing dextran, nuclei were isolated in high yield from cells of Gymnodinium nelsoni, a marine dinoflagellate. Most of the DNA, but less than onetenth of the RNA, of the original cells was recovered in the purified nuclei. The nuclei appeared substantially intact as observed by light or electron microscopy. The isolated nuclei were capable of incorporating tritiated uridine triphosphate into material insoluble in cold acid. The general procedure was found to be applicable also to two species of diatoms.     

Inhibited and uninhibited infants "grown up": adult amygdalar response to novelty

Infants with an inhibited temperament tend to develop into children who avoid people, objects, and situations that are novel or unfamiliar, whereas uninhibited children spontaneously approach novel persons, objects, and situations. Behavioral and physiological features of these two temperamental categories are moderately stable from infancy into early adolescence and have been hypothesized to be due, in part, to variation in amygdalar responses to novelty. We found that adults who had been categorized in the second year of life as inhibited, compared with those previously categorized as uninhibited, showed greater functional MRI signal response within the amygdala to novel versus familiar faces.     

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To examine the fate of P added to soils as fertilizer and to assess potential P losses to groundwater, different forms of P at increasing depths in soils and P concentration in effluents from tile drains were determined. The estimates of soil P showed that the fertilizer P applied over a number of years accumulated mainly in the plow layer, suggesting that P losses to groundwater from cultivated soils with deep water table are minimum. Analyses of effluents obtained over a 1 yr period from tile drains in four soils in different crops, however, showed that the concentration of P varied from 12 ppb to 124 ppb. The concentration of P in effluent from the soil with the largest amount of P in the plow layer remained the largest throughout the year. Apparently, in cultivated soils with the tile drains, flooding may produce reducing conditions resulting in greater mobility of P.     

Historical trends of airborne trace metals in Detroit from 1971 to 1992

Ambient concentrations of particulate Fe, Zn, Ph, Ni, Cr, Cd and Hg were measured at nine sites located in the metropolitan area of Detroit from 1971 to 1992. The ambient concentrations of all the trace metals were found to be generally higher at industrial and commercial sites. The concentrations show significant variations between residential and commercial areas and between residential and industrial areas; however, no significant variation was found between the industrial and commercial settings. The spatial variation of trace metal levels within the urban area was influenced by the frequency distribution of the wind direction as well as type and location of emission sources. The ambient concentrations of the trace metals during the decade of 1971–1981 declined by 37–88%. In the 1980s many of the trace metals reversed this trend with the exception of Fe and Pb which continued to decline at annual rates of 2% and 9.8%, respectively. The sharp decrease in Pb concentrations during the 1980s, reflected the significant reduction of Pb content in gasoline from 0.28 g/liter in the 1982 to 0.026 g/liter in the 1989. The ambient concentrations of Zn, Ni, Cr, Cd and Hg showed an upward trend during the 1980s with an annual rate in the range of 0.6% to 10.6%. The long-term trends of selected U.S. market parameters, analyzed as potential long-term indicators of emission sources activityies, were consistent with the changes of ambient concentrations, the correlation coefficient being in the range of 0.58 to 0.84 for most of the trace metals.