A SURVEY OF SILAGE QUALITY ON NORTHLAND DAIRY FARMS

A survey was made on 31 dairy farms of the botanical and chemical composition of pasture being ensiled and of the chemical composition of the resultant silages. Despite the wide range in grass (37-100s) and legume (O-SO%) components, drymatter content (20-56v/o), soluble carbohydrate (4-19s) and neutral detergent fibre (NDF) (43-69%) contents, NDF was the only component significantly correlated with dry matter digestibility (range 53-76%) (r = -0.77; P &gt; 0.01). Wilting time ranged from 2-47 hours except in seven of the silages which were not wilted. Four silages were not covered with polythene but were similar in chemical composition to other silages when sampled in summer. Phosphorus (P) (.lS-.42% DM) and nitrogen (N) (l.O-2.2% DM) in silage were below published requirements for cows in mid lactation in more than 75% of the silages. It is suggested that either or both of these minerals may limit milk production from cows fed a predominantly silage ration during summer. Ensiling of less-mature pasture is advocated to ensure a more digestible feed which is likely to contain adequate levels of P and N.</jats:p

Ripgut brome (&lt;i&gt;Bromus diandrus&lt;/i&gt;) distribution in relation to topography and management on seven high country properties in the South Island

Seeds of ripgut brome an annual grass can contaminate the wool pelt and carcasses of sheep grazing on high country properties The distribution of ripgut brome on seven high country properties in Marlborough Canterbury and Otago was determined during December 2006 to February 2007 The presence of ripgut brome was measured in paddocks of different management intensities at altitudes ranging from 400 to 1400 m Ripgut brome grass presence was lower in sites managed less intensively (eg less fertiliser and oversowing) in hard than laxly grazed sites and in sites of high exotic perennial grass cover It was more prevalent on stock camps than off stock camps and on steeper slopes and sunny aspects but was unaffected by legume cover shrub presence or altitude The results suggest that increased grazing intensity and enhanced plant competition are methods that may be used to suppress ripgut brome on hill and high country properties</jats:p

Spring and summer and wool growth pasture feeding and ewe reproduction

Effects of pasture feeding level during lactation and over summer on ewe wool growth and ovulation rate were assessed in 1983-84 and 1984-85. Two levels of pasture feeding (lactation high and lactation low) from parturition to weaning (10 weeks) produced 8 to 10 kg liveweight difference in ewe liveweight at weaning. Groups (n = 40) were offered pasture allowances of 0.8, 1, 1.4, 2 or 5 kg DM/ewe/day from weaning until after the third synchronzied oestrus in April. Ewes on the lower allowances tended to reach a stable liveweight and those on 5 kg DM/ewe/day gained throughout. Other groups were offered low allowances during summer and then 5 kg DM/ewe/day after the first recorded oestrus. Mean dates for synchronised oestrus were 2 March, 19 March and 5 April. Ovulation rate increased by 0.15 corpora-lutea/ewe ovulating at each successive oestrus, and increased by 0.047 corpora lutes/ewe ovulating for each kg increase in liveweight at oestrus. These effects accounted for 77% of the variation in ovulation rate between treatments across years. The effects of flushing, lactation or summer liveweight change were small and generally non-significant. Lactation feeding affected wool growth during lactation as well and had carryover effects through the summer when lactation low ewes grew 10% less wool irrespective of the level of summer feeding. Keywords ewe, wool growth, ovulation rate, lactation, summer feeding, liveweight, flushing</jats:p