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Twenty four mature twin-bearing ewes in late pregnancy were used to compare the effects of feeding grass silage (GS), maize silage (MS) or a maize silage/ensiled super pressed pulp mixture (MS/ESPP), 60:40 on a DM basis, on voluntary feed intake, ewe weight and body score changes, lamb birth weight, colostrum yield and quality, and lamb growth rate to weaning. Each of the diets was supplemented with a barley/soya-bean concentrate (BS) containing 208 g crude protein kg −1 DM. The trial commenced on day 98 of pregnancy from whence the ewes were individually fed and their diet supplemented with BS at the rate of 213.5 g DM ewe−1 day−1 from days 98 to 125 of pregnancy and at 427 g DM day−1 from days 126 of pregnancy until parturition. The ewes were milked at 1, 10, and 18 h post lambing. Silage DM intakes (kg day−1) were higher on the MS/ESPP diet (P < 0.05) than on the GS or MS silage-based diets. From days 98 to 142 of pregnancy, mean ewe weight gains (kg) of 9.11, 11.37 and 13.12 (sem = 1.009) (P < 0.01), and body condition losses of 0.14, 0.34 and 0.02 (sem = 0.105) (P < 0.05) were recorded for GS, MS and MS/ESPP, respectively. Ewe body weight losses between day 98 and 24 h post lambing (kg) were 2.50, 2.44 and 1.44 (sem = 1.152) and litter birth weights (kg) of 9.84, 9.36 and 10.62 (sem = 0.434) (P < 0.05) were recorded for GS, MS and MS/ESPP, respectively. Colostrum yield (g) at 1 h of 605 ± 92.0, 526 ± 78.5 and 711 ± 74.8 and total colostrum yield (g) at 18 h of 1927 ± 163.3, 1690 ± 139.4, 2208 ± 132.7 (P < 0.05) were recorded for GS, MS and MS/ESPP, respectively. Overall, there were only minor differences in performance between grass and maize silages but when 40% of the maize silage was replaced with ESPP, both DM and total DM intakes were increased relative to the MS treatment; the ewes gained more weight and lost least body condition, total colostrum yield was higher, and the lambs had a higher growth rate up to weaning.

While the benefits of using maize silage and ensiled super pressed pulp in the diets of lactating cows has been well researched, little work has been done on the inclusion of these feeds in the diets of pregnant ewes. The objective of this experiment was to compare the effects of the nutritive value of grass silage, maize silage and a maize silage/ensiled super pressed pulp (60:40) mixture, when offered to mature twin bearing ewes in late pregnancy on ewe and lamb performance.

The results of an impedance study of the electrochemistry of solid, plain porous and porous polymeric (incorporating polystyrene) zinc electrodes in 1 M NaClO4 solution are presented. The transformation of the solid zinc electrode to the porous format results in great enhancement of reaction rates, but this is subject to limitations on removal of reaction products by mass transfer. Thus porous electrodes are prone to gas-filling by the HER, and to film formation and pore plugging at anodic overpotentials. The incorporation of moderate (10%) amounts of an electro-inactive polymer, such as polystyrene, have little effect on electrode activity. Large amounts (50%) can produce an anomalous electrode which appears perfectly porous, but which can be little more active than the solid electrode.