This study explored the potential for using seed cake from hemp (Cannabis sativa L.) as a protein feed for dairy cows. The aim was to evaluate the effects of increasing the proportion of hempseed cake (HC) in the diet on milk production and milk composition. Forty Swedish Red dairy cows were involved in a 5-week dose-response feeding trial. The cows were allocated randomly to one of four experimental diets containing on average 494 g/kg of grass silage and 506 g/kg of concentrate on a dry matter (DM) basis. Diets containing 0 g (HC0), 143 g (HC14), 233 g (HC23) or 318 g (HC32) HC/kg DM were achieved by replacing an increasing proportion of compound pellets with cold-pressed HC. Increasing the proportion of HC resulted in dietary crude protein (CP) concentrations ranging from 126 for HC0 to 195 g CP/kg DM for HC32. Further effects on the composition of the diet with increasing proportions of HC were higher fat and NDF and lower starch concentrations. There were no linear or quadratic effects on DM intake, but increasing the proportion of HC in the diet resulted in linear increases in fat and NDF intake, as well as CP intake (P , 0.001), and a linear decrease in starch intake (P , 0.001). The proportion of HC had significant quadratic effects on the yields of milk, energy-corrected milk (ECM) and milk protein, fat and lactose. The curvilinear response of all yield parameters indicated maximum production from cows fed diet HC14. Increasing the proportion of HC resulted in linear decreases in both milk protein and milk fat concentration (P 5 0.005 and P 5 0.017, respectively), a linear increase in milk urea (P , 0.001), and a linear decrease in CP efficiency (milk protein/CP intake; P , 0.001). In conclusion, the HC14 diet, corresponding to a dietary CP concentration of 157 g/kg DM, resulted in the maximum yields of milk and ECM by dairy cows in this study.

The aim of this study was to determine the levels of lead and cadmium in chicken, pork, beef, lamb and turkey samples (both meat and meat products), collected in the island of Tenerife (Spain). Lead and cadmium were measured by graphite furnace atomic absorption spectrometry (GFAAS). Mean concentrations of lead and cadmium were 6.94 and 1.68 microg kg(-1) in chicken meat, 5.00 and 5.49 microg kg(-1) in pork meat, 1.91 and 1.90 microg kg(-1) in beef meat and 1.35 and 1.22 microg kg(-1) in lamb meat samples, respectively. Lead was below the detection limit in turkey samples and mean cadmium concentration was 5.49 microg kg(-1). Mean concentrations of lead and cadmium in chicken meat product samples were 3.16 and 4.15 microg kg(-1), 4.89 and 6.50 microg kg(-1) in pork meat product, 6.72 and 4.76 microg kg(-1) in beef meat product and 9.12 and 5.98 microg kg(-1) in turkey meat product samples, respectively. The percentage contribution of the two considered metals to provisional tolerable weekly intake (PTWI) was calculated for meat and meat products. Statistically significant differences were found for lead content in meats between the chicken and pork groups and the turkey and beef groups, whereas for cadmium concentrations in meats, significant differences were observed between the turkey and chicken, beef and lamb groups. In meat products, no clear differences were observed for lead and cadmium between the various groups.

Abstract– Studies were performed with both a mechanical and a photosensory arrangement of the experimental tanks. Silver (migratory) eels were more active than yellow (stationary) eels. Comparison of pooled data on yellow eels tested under natural geomagnetic field conditions with those on eel tested under unnatural ones prcded no evidence of difference in activity. Silver and yellow eels showed stronger activity during the 6 days around new moon compared with the phase around full moon as well as a peak before new moon and a smaller peak before full moon. Under each kind of unnatural field condition, the activity relationships reversed or were cancelled. The directional choice of eels under natural conditions (controls) pointed to magnetic NW and mostly also in the opposite direction. When the magnetic north was changed by 90°, the tested yellow eels followed this change to about the same degree. The additional change of both the inclination (from 68° or 45° or 30°) and total intensity (by a reduction to 31% of the natural field) resulted in a change of the preferences of about 90° relative to magnetic north. Reversal of magnetic north by 180°, which is identical to a change of the inclination from 68° to 112°, also resulted in a change of the preferences by about 90°. Three experiments using compensation of both the horizontal and the vertical geomagnetic field led to circular directional preferences at random in two cases and in one case to about NW of the residual field magnetic north. The navigational abilities of the eel, on the basis of its magnetic sensitivity, are discussed.

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The objective of this study was to evaluate ruminal degradability and intestinal digestibility of crude protein (CP) and amino acids (AA) in hempseed cake (HC) that were moist heat treated at different temperatures. Samples of cold-pressed HC were autoclaved for 30 min at 110, 120 or 130°C, and a sample of untreated HC was used as the control. Ruminal degradability of CP was estimated, using the in situ Dacron bag technique; intestinal CP digestibility was estimated for the 16 h in situ residue using a three-step in vitro procedure. AA content was determined for the HC samples (heat treated and untreated) of the intact feed, the 16 h in situ residue and the residue after the three-step procedure. There was a linear increase in RUP (p = 0.001) and intestinal digestibility of RUP (p = 0.003) with increasing temperature during heat treatment. The 130°C treatment increased RUP from 259 to 629 g/kg CP, while intestinal digestibility increased from 176 to 730 g/kg RUP, compared to the control. Hence, the intestinal available dietary CP increased more than eight times. Increasing temperatures during heat treatment resulted in linear decreases in ruminal degradability of total AA (p = 0.006) and individual AA (p<0.05) and an increase in intestinal digestibility that could be explained both by a linear and a quadratic model for total AA and most individual AA (p<0.05). The 130°C treatment decreased ruminal degradability of total AA from 837 to 471 g/kg, while intestinal digestibility increased from 267 to 813 g/kg of rumen undegradable AA, compared with the control. There were differences between ruminal AA degradability and between intestinal AA digestibility within all individual HC treatments (p<0.001). It is concluded that moist heat treatment at 130°C did not overprotect the CP of HC and could be used to shift the site of CP and AA digestion from the rumen to the small intestine. This may increase the value of HC as a protein supplement for ruminants.