Australian feral goats have recently been found to produce commercially viable quantities of the luxury fibre cashmere (Smith, Clarke & Turner, 1973). Cashmere is the fine down produced by secondary follicles as an undercoat during winter. Fibre diameter ranges from 8 to 24 μm with a mean diameter of 16 μm. Unlike modern breeds of sheep such as the Merino which exhibit almost continuous wool growth, cashmere growth is distinctly seasonal with fibre growth commencing in summer (long daylength) and reaching a maximum length in early winter (short daylength) (McDonald, 1985). The cashmere is cast in spring with growth recommencing again in summer.

Although over 90% of small ruminant production in Nigeria is done under native husbandry or semiintensive management, relatively little information on their reproductive performance is available. However, information on the reproductive performance of Nigerian small ruminants under intensive management conducted at Research Centres or Institutes is readily available (Adu, Buvanendran & Lakpini, 1979; Adu, Brinckman & Kuteyi, 1979; Molokwu & Umunna, 1980; Osinowo & Ekpe, 1985). Such reproductive information includes age at first lambing or kidding, birth weight, lambing or kidding intervals, seasonal effects and conception rates. Although the latter findings are meant for dissemination through Extension Services to rural producers for application, records of the effects of such application are scanty.

Agronomic experiments have shown that nitrogen applied in organic manures gives variable responses in grass growth (van Dijk & Sturm, 1983; Smith, Unwin & Williams, 1985). In a series of field trials in southern England, the average apparent recovery in herbage of the nitrogen from cow slurry was only 13% (Unwin, Pain & Whinham, 1986). The volatilization of ammonia from spread slurry is one possible mechanism for the nitrogen inefficiency (Freney, Simpson & Denmead, 1983; Ryden, 1984). Direct measurements of ammonia loss from land surfaces can be made by micrometeorological methods (Denmead, 1983) and, using the micrometeorological mass balance technique, high rates of ammonia loss were recorded after the land spreading of liquid dairy cattle manure in Canada (Beauchamp, Kidd & Thurtell, 1982). The micrometeorological mass balance method has been used in England to measure ammonia loss from a grazed sward (Ryden & McNeill, 1984). This paper presents the results of an experiment where the same method was used to measure the ammonia loss after land-spreading cattle slurry in Northern Ireland.

J. agric. Sci., Camb. (1986), 107, 285–297

The authors regret that Fig. 9 relating sucrose weight to total dry weight contained a few misplotted measurements. The sixth group of bivariate observations (five data points) were plotted a factor of 10 g/plant too light in the y-direction (sucrose weight). This error was not present in curve fitting, thus the fitted relationship (Fig. 9; Table 2) is correct fitted relationships on Figs 5 and 9 and thus also remain unchanged. Figure 9 should be presented as