Prevalence of Giardia and Cryptosporidium in beef cows in southern Ontario and in beef calves in southern British Columbia

In 1998 and 1999, fecal samples were collected from 669 beef cows on 39 farms located within 10 counties of Ontario. Overall prevalences of Giardia, Cryptosporidium muris, and Cryptosporidium parvum in cows were 8.7%, 10.6%, and 18.4%, respectively. Of the 39 farms sampled, Giardia was detected on 64%, Cr. muris on 72%, and Cr. parvum on 90%. Cryptosporidium parvum was detected in 28% of the cows in 1998 and in 5.2% in 1999. Differences between the 2 y were attributed to sampling during calving in 1998 and during gestation in 1999. In 1998, Giardia, Cr. muris, and Cr. parvum were detected in herds provided with municipal water. In 1998, 193 calves were sampled from 10 farms, representing 4 watersheds, in British Columbia. Thirty-six percent of the calves exhibited signs of diarrhea. Overall prevalences of Giardia and Cryptosporidium spp. in calves were 36% and 13%, respectively. There was evidence that calves with Giardia were more likely to develop scours. Restricting cattle from surface water during periods of high shedding may reduce watershed contamination.     

The three-loop pulley suture versus two locking-loop sutures for the repair of canine achilles tendons

OBJECTIVE: To compare a 3-loop pulley suture pattern with 2 locking-loop sutures for the repair of components of the canine Achilles mechanism. STUDY DESIGN: In vitro biomechanical study. ANIMALS: Forty-eight paired tendons collected from 9 canine cadavers. METHODS: Paired tendons were repaired with either a 3-loop pulley suture or 2 locking-loop sutures and tensile tested to failure. To ensure accurate anastomosis gap measurement a direct, non-contact, method of gap measurement, using digital video, was devised. Load initiating gap formation (defined as load at a 1 mm gap) and load producing a 3 mm gap were evaluated in addition to maximum load, gap at failure, mode of failure, and time spent placing the sutures. RESULTS: Maximum load values were similar for both repairs. The mean 1 mm gap loads were 44.0 and 18.4 N, and the mean 3 mm gap loads were 56.3 and 34.7 N, for the 3-loop pulley pattern and the 2 locking-loops, respectively; these differences were statistically significant. The 3-loop pulley pattern was faster to place and resulted in a smaller gap at failure. All but 2 repairs failed by suture pull out. CONCLUSIONS: The 3-loop pulley pattern is more resistant to gap formation during tensile loading, and is quicker to place, than 2 locking-loop sutures. CLINICAL RELEVANCE: Gap formation can significantly delay tendon healing. Tendon repairs with a gap >3 mm are reported to be at increased risk of rupture during the first 6 weeks postoperatively.     

Indigenous and spontaneous vegetation: their relationship to urban development in the city of Leeds, UK

The concepts of indigenous and spontaneous vegetation are considered as subsets of the broader category, semi-natural vegetation. Indigenous vegetation is conceptualised as that which has originated in a rural landscape and developed over a time period of several centuries or more, either naturally or as a result of traditional management methods, together with the environmental conditions supporting it. In contrast, spontaneous vegetation is that which has naturally colonised derelict urban sites, mainly within the last century. An investigation, using map and aerial photographic data, examined the relative proportions of potentially indigenous and spontaneous vegetation on proposed development sites in Leeds, a large industrial city in the UK. Results suggested that spontaneous vegetation occupied approximately 13% by area of the development sites while possible indigenous vegetation occupied as little as 5%. However, further analysis suggested that approximately 25% of the proposed development sites were within 0.5 km of a designated site containing indigenous vegetation. It is argued that both types of semi-natural vegetation can make positive contributions to the urban environment but that public perception of spontaneous vegetation and, in particular, the locations where it occurs, are often negative. Further research into public perceptions of semi-natural vegetation and ways of incorporating it into urban development are required.     

Efficacy of a modified live intranasal bovine respiratory syncytial virus vaccine in 3-week-old calves experimentally challenged with BRSV

Two experimental bovine respiratory syncytial virus (BRSV) challenge studies were undertaken to evaluate the efficacy of a single intranasal dose of a bivalent modified live vaccine containing BRSV in 3-week-old calves. In the first study, vaccine efficacy was evaluated in colostrum deprived (maternal antibody negative) calves 5, 10 and 21 days after vaccination. Nasal shedding of BRSV was significantly reduced in vaccinated calves challenged 10 or 21 days after vaccination. Virus excretion titres were also reduced in vaccinates challenged 5 days after vaccination but reduction in duration of shedding and total amount of virus shed were not statistically significant. Clinical disease after challenge in this study was mild. In the second study, vaccine efficacy was assessed in calves with maternal antibodies against BRSV by challenge 66 days post-vaccination. Vaccination significantly reduced nasal shedding after challenge and the severity of clinical disease was also reduced.     

水温对幼鲵生长影响的初步研究

研究了不同时间段泉水和河水对幼鲵(Andrias davidanus)生长的影响。结果显示:幼鲵在不同时间和不同地点增重存在差异。第二阶段幼鲵平均日增重极显著高于第一阶段(P<0.01)。1号点(泉水)幼鲵平均增重和日平均增重极显著高于2号点(河水)幼鲵(P<0.01);第一阶段1号点日平均水温极显著高于2号点(P<0.01),最低温度较河水高6.95℃,且1号点水温变化较小。结果表明,水温是影响幼鲵生长的重要因素之一。     

Extreme nighttime air temperatures in 2010 impact rice chalkiness and milling quality

Research shows that elevated nighttime air temperatures (NTATs) contribute to increased chalk formation and reduced milling quality in rice. Arkansas rice-growing regions experienced exceptionally warm weather conditions during the summer of 2010, providing an opportunity to test this hypothesis under extreme conditions. Data from a previous study, conducted in years 2007-2009 (Ambardekar et al., 2011), was extended to include 2010 data, and analyzed to evaluate the correlations of 95th percentiles of NTAT frequencies (NT₉₅) occurring during reproductive (R) stages of six rice cultivars with chalk and peak head rice yields (pHRYs). Long-grain cultivars produced chalk values that were positively correlated to NT₉₅, and pHRYs that were inversely correlated, during the R5 through R8 stages. Medium-grain cultivars, Bengal and Jupiter, which in the original study showed little or no response to elevated NTATs during all R-stages, showed significant positive correlations between chalk, and negative correlations between pHRY, and NT₉₅, during the R7 and R8 stages. The 2007-2009 analyses indicated quadratic relationships of chalk with NT₉₅ and linear relationships of pHRY with NT₉₅. However, addition of the 2010 data indicated that both of these relationships were quadratic in nature. The extreme temperatures observed in 2010 also verified that while cultivars vary in their level of resistance to NTAT effects, all of the rice cultivars analyzed throughout the four-year study exhibited some degree of susceptibility to extreme NTAT temperatures occurring during critical grain-filling stages.     

Identification of novel QTL for leaf traits in soybean

Several leaf traits of soybean (Glycine max L. Merr.), including leaf area (LA), leaf shape (LS) and specific leaf weight (SLW) may be related to soybean yield. The objective of this study was to identify novel quantitative trait loci (QTL) for LA, LS and SLW in a recombinant inbred line (RIL) population. The phenotype data were collected in 2011 and 2012 for 93 F_7:10 RILs using a randomized complete block design with 2 replicates each year. Five hundred and sixteen single‐nucleotide polymorphism (SNP) markers and the phenotype data were used to detect QTL using single marker analysis (SMA) and composite interval mapping (CIM). Single markers analysis identified 26 QTL for the three traits, of which 17 were novel and the rests were previously reported QTL. Most of these QTL were also identified by CIM. Most QTL reported in this study were in close proximity (<1 cM) of one or more SNP markers. These publicly available SNP markers with close linkage to LA, LS and SLW should be useful for marker‐assisted breeding for these traits.     

Testing prescribed fire as a tool to promote Scots pine <Emphasis Type="Italic">Pinus sylvestris</Emphasis> regeneration

Techniques for encouraging natural tree regeneration are of increasing interest to managers of Scots pine Pinus sylvestris forests. We tested prescribed fire at a management scale, with deer present or excluded, as a means of increasing rates of Scots pine forest expansion on heathland. At a semi-natural pinewood in Scotland, ten experimental blocks were established, within range of pine seed-fall. Each block comprised four, 100 m² plots. Two plots at each site were burnt and two fenced, allowing the effects of burning on pine regeneration to be measured at two levels of deer abundance. We monitored pine seedlings, seed-fall, deer dung and vegetation for 5 years following treatment. Differences in seedling detection rates between treatments were quantified using dummy seedlings, and analyses corrected accordingly. Mean new pine seedling establishment was 9.8 times higher on burnt ground than unburnt ground (confidence intervals 3.2–30). Differences were even more pronounced in a year of high seed-fall, and following fires with low rates of spread. Establishment rates varied strongly between experimental blocks. Exclusion of deer increased establishment rates, but only in the first 2 years after fire. There was evidence that both seedling survival, and cumulative recruitment of older (over 12 months) seedlings, were improved by prescribed burning. Our results support the use of prescribed fire as a tool to promote increased Scots pine seedling establishment. This technique is likely to give strong fine-scale variation in seedling densities, and so would most suit areas where a variable spatial pattern of regeneration is sought, for landscape or naturalness reasons. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.