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This study aims to compare the evidence base and practical results of the Joint Recommendations for Reporting Carotid Ultrasound Investigations in UK, published in 2009, and existing carotid scan protocols based on the Society of Radiologists in Ultrasound 2003 Consensus. A prospective sequential evaluation of the 2009 recommendations was performed at the University Hospital of Wales, Cardiff. Additional measurements in line with the recommendations were made during carotid scans. The grading of internal carotid artery stenosis using the 2003 and 2009 UK recommendations, and recommended measures of PSV, PSV ratio and St Mary’s ratio were compared. In comparison to PSV classification, PSV ratio produced lower stenosis classification in 29% and 24% of cases in the 50–69% and 70–89% stenosis bands respectively. St Mary’s ratio produced poor classification agreement across all bands, particularly the 50%–69% stenosis band. Agreement of two measures is recommended for diagnostic confidence; however, in the 50%–69% and 70%–89% stenosis bands, agreement of two measures only occurred in 70% of scans. This evaluation suggests that the use of three measurements in the 2009 recommendations complicates rather than aids diagnosis, especially in the 50%–69% and 70%–89% stenosis bands, and does not provide significant improvement over the 2003 guidelines. No evidence was found to support the combined use of the three measures.

Pasture was ensiled with increasing amounts of whole barley in stacks [0, 75 (SLB), 150 (SMB) kg/t fresh pasture] or in 200-L drum silos 10, 75 (DLB), 150 (DMB), 225 (DHB) kg/t fresh pasture]. All silages were well fermented with low pH values and low ammonia concentrations. The addition of barley significantly (P<0.05) increased the dry matter content of the resultant stack silages by 29% (SLB) and 54% (SMB) and significantly (P<0.05) increased residual water-soluble carbohydrate levels in the SMB silage compared with untreated stack silage. Incorporation of barley with pasture in 200-L silos significantly (P<0.001) increased the dry matter of the resultant silages and significantly (P<0.01) reduced effluent production by 55, 93, and 100% for DLB, DMB, and DHB compared with the untreated silo silage. Dry matter, nitrogen, and lactic acid concentrations in effluent did not differ significantly, although total losses of these components were significantly (P<0.01) higher in the untreated silage.| The stack silages were fed to beef steers (293 kg) and compared with silage diets containing equivalent levels of rolled barley mixed with untreated silage at feeding. Irrespective of method of feeding barley, animal performance improved compared with feeding a silage-only diet. At equivalent levels of barley inclusion, liveweight gains were higher and feed conversion ratios lower with the rolled barley diets. The results indicate that the addition of barley to low dry matter pasture during ensiling can reduce effluent production and the loss of soluble nutrients; however, it is likely that the grain will need to be processed to maximise subsequent animal production.

Supplements of barley, a barley-lupin mix (BL), or lupin grain containing urea plus ammonium sulfate (4% + 0.5%, low N; 6% + 1.0%, high N) were offered ad libitum to Holstein-Friesian steers. Supplement intake was restricted by increasing the amount of urea and ammonium sulfate (average intake of 1.7 and 1.4 kg DM/day.100 kg LW for cattle offered low and high N supplements). Supplement intakes were 14-56% greater than predicted from previous studies. Despite the high N content of the diet consumed by steers offered supplements containing lupin (up to 4.8% N with the high N supplement), feed conversion efficiency (FCE) of these cattle was better (P<0.01) than for cattle offered barley supplements (5.3, 5.8, 6.1 kg DM/kg LW gain for lupin, BL, barley). In another experiment, Holstein-Friesian steers offered grain immediately before an ad libitum supplement of barley containing 8% urea consumed 30-50% more grain than those without immediate prior exposure to grain. When the intakes of Holstein-Friesian steers offered ad libitum supplements of either barley or lupin containing either 8% urea or 5.7% diammonium phosphate (DAP) were compared, supplement intakes across grains averaged 1.3 and 0.6 kg DM/day. 100 kg LW. These levels of urea and DAP were predicted to result in similar intakes. However, to achieve a desired level of supplement intake, less DAP was required than urea. Both liveweight gain and FCE were 22-24% greater for cattle offered lupin than those offered barley supplements. Adding urea at 0, 0.5, or 1.0% to a barley supplement containing 4% DAP did not affect supplement or hay intakes by Holstein-Friesian steers, which averaged 0.8 and 1.7 kg DM/day.100 kg LW, respectively. Liveweight gain and FCE were increased by 25% by adding urea to a barley supplement containing DAP. Finally, 3 different methods of introducing a grain supplement containing DAP to Holstein-Friesian steers were compared: a 4-phase, 16-day introductory period; a 2-phase, 7-day introductory period; no introductory period. In steers with and without immediate prior exposure to grain, neither method of introduction nor previous exposure to grain affected supplement intake, liveweight gain, or FCE.

The preweaning growth of the progeny from 2531 first-calf heifers calving on commercial properties in the south-west of Western Australia was studied over 5 years. Animals included the progeny of Angus sires mated to Angus, Angus x Friesian, Simford, Hereford and Beef Shorthorn crossbred heifers; the progeny of Hereford sires mated to Hereford, Hereford x Friesian, and Beef Shorthorn crossbred; and those of Devon crossbred, Simford or Wokalup multibreed heifers mated inter se. Calves were born between mid January and July of each year and date of birth, calving information and calf growth through to weaning at an average age of 230 days were recorded. Data recorded on the calves' dams included regular liveweight and condition score assessment and the date of second calving. Angus-sired calves were lighter at birth than Hereford-sired calves; breed means ranged from 25.1 kg for purebred Angus to 33.2 kg for Wokalup multibreeds, with male calves weighing 1.4 kg more than females at birth. Calf birth weight was positively and linearly related to weight of dam at the beginning of joining. Breed of calf, sex of calf, year of birth, day of the year born, liveweight and liveweight change of the dam at the beginning of rejoining all significantly influenced calf growth, with up to 64% of variation accounted for. At 50 days of age, Devon crossbreds, Simfords and Wokalup multibreeds were significantly heavier than crossbred Hereford or Angus calves, and this trend persisted until weaning. The average growth rate to 200 days of Angus calves was 0.113 kg/day slower, and Hereford calves 0.77 kg/day slower, than the average growth rate of their respective crossbred calves. Heaviest 200-day weights were found in Devon crossbred (235 kg), Simford (221 kg) and Wokalup multibreed (219 kg) calves. A strong seasonal influence on calf growth was detected. Each 1 day increase in calf age in calves born between mid January and June resulted in 0.29 kg extra liveweight at 100 days and 0.68 kg extra liveweight at 200 days of age. Overall, the liveweight of the dam at the beginning of re-joining was positively associated with calf growth, with 0.119 kg of calf liveweight/kg dam liveweight at 100 days and 0.123 kg at 200 days. There was less effect of dam liveweight in Herefords and Hereford x Friesians on calf growth to 200 days, but this relationship was closer in faster growing and later maturing breeds, including Angus x Friesian, Simford, and Wokalup multibreed. The dairy crossbreeds generally lost weight at the beginning of re-joining, resulting in a negative association between this weight change and calf growth to 100 days. No assistance was required in 93% of calvings and the highest incidence of dystocia corresponded with the highest birth weight calves in Wokalup multibreeds. The most common calving difficulty was an apparently slow birth where no assistance was given, resulting in a stillborn calf. Male calves experienced 3 times the level of dystocia recorded for female calves. There was no association detected between dystocia and dam liveweight subsequent to calving. The study highlighted the importance of dam breed, liveweight and condition of the dam and timing of calving as important influences on the growth of progeny reared by first-calf heifers.

A 5-year study was conducted using 3498 heifers on commercial properties in the south-west of Western Australia. Breed types represented were Angus, Angus x Friesian, Angus x Hereford, Devon crossbred, Hereford x Friesian, Hereford, Hereford x Simmental, Beef Shorthorn crossbred, Wokalup multibreed and Simmental. Heifers joined at 13-18 months of age were monitored throughout the growing season with emphasis on measurement of liveweight and condition score during joining (range 9-21 weeks) and subsequent reproductive performance. The timing and level of conception were examined for their relationship with liveweight, condition and their rates of change during the joining period. Mean liveweight at conception varied significantly among breeds and apparently corresponded to maturity type. Liveweights (kg) of heifers were: Angus, 255; Hereford, 281; Angus x Friesian, 290; Hereford x Friesian, 295; Simford, 326; Simmental, 416. There were large variations within breeds and between management groups in liveweight and rate of weight change at conception, the range within breed covering at least 160 kg (Angus x Hereford) and at most 240 kg (Simford). Most breeds of heifer conceived at a condition score of 2.0. Positive liveweight gains between 0.39 kglday in Angus heifers and 1.07 kgtday in Simmental heifers, and gains in condition, occurred in all breeds at conception. However, there was no significant relationship between rate of liveweight or condition score change early in the joining period, with calving rate in any breed.In 7 of 10 breeds higher calving rates were associated with heavier liveweight during the joining period. These trends were consistent throughout joining, with the strongest relationships determined by logistic regression analysis using liveweight at the beginning of joining. Statistically significant differences in calving rate were also found between light heifers, <220 kg for Herefords and Hereford x Friesian crossbreds, or <255 kg for larger or later maturing breeds including Angus x Friesian, Simford and Wokalup multibreed, and heifers in heavier liveweight categories. Similarly, the proportion of heifers pregnant was usually lower below a condition score of 1.5; highest fertility was commonly observed at condition scores of 1.5-2.5 during joining. The time from the beginning of joining to conception averaged less than 21 days for most breeds. Significant linear regressions between the interval from the beginning of joining to conception and either liveweight, condition or their rates of change in early joining showed that heifers which were heavier, in better condition, or gaining weight quickly, conceived earlier. These relationships were demonstrated in only half of the breeds in the study. The current data extend the range of cattle breeds for which there is some guide to target weights and condition scores for first conception under grazing management in southern Australia, and identify the relative importance of static and dynamic liveweight effects on heifer fertility.

A 5-year study was conducted using 2531 first-calving heifers on commercial properties in the south-west of Western Australia. Breed types included Angus, Angus x Friesian, Angus x Hereford, Devon crossbred, Hereford x Friesian, Hereford, Simford, Beef Shorthorn crossbred, Wokalup multibreed and Simmental. Heifers first calving between 22 and 29 months of age were monitored from first until second calving, with the emphasis on liveweight and condition score measured during joining (range 9-21 weeks) and subsequent reproductive performance. The timing and level of reconception after first calving were tested for their relationship with liveweight, condition and their rates of change during joining. At second conception, mean liveweight varied widely both within and among breeds but apparently corresponded to maturity type. Liveweights (kg) of first-calvers were: Angus, 336; Hereford, 368; Angus x Friesian, 378; Simford, 423; Simmental, 467. At second conception, first-calvers were generally making moderate liveweight gains (0.2-0.6 kg/day) and most conceived at a condition score of 1.5-2.0. In 8 breeds with sufficient data for analysis, increased calving rates were related to heavier liveweight or better condition during joining, with the strongest relationships based on weight or condition at the beginning of joining. In general, fertility was adversely affected by liveweight <310 kg at the start of joining in early-maturing breeds such as Angus, Hereford and Beef Shorthorn crossbred and liveweight <345 kg in later maturing or larger breeds including Simford, Angus x Friesian crossbred and Wokalup multibreed. In addition, the fertility of the larger breeds was more influenced by liveweight, with greater partial regression coefficients, than was fertility in Angus or Herefords. First-calvers with condition scores less than an apparent threshold of 1.5, and those losing more than 0.6 kg/day, had lower calving rates than their counterparts in better condition or those losing less weight. In both early and later maturing breed types there was a linear relationship between higher calving rates and increasing liveweight gain. The average time of second conception for most breeds was within 5-6 weeks of the start of joining and most intercalving intervals were 370-390 days. Both time to conception and the intercalving interval were negatively and linearly related to liveweight (7-14 days reduction/100 kg), condition (7-13 days reductionlunit of condition), or weight change early in joining. Generally, heavier weights were required to effect the same reduction in time to conception in larger breeds such as Angus x Friesian, 314 Hereford x Simmental and Wokalup multibreed than in early-maturing breeds such as Angus or Hereford. Development of guidelines to producers based on second-conception weights, condition scores and the log-linear relationships derived for the breeds and crossbreeds in this work is discussed in the light of the poor reproductive performance sometimes found in this class of breeder.