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11.
The effect of spring application of separated liquid pig manure (LPM) in combination with medium to high levels of inorganic nitrogen (N) to winter wheat was investigated in a field trial study at two sites in two successive growing seasons (2007–2008). The key crop parameters examined were crop N uptake (CNU), N use efficiency and grain yield. The LPM product (3.5–4.0 g/kg total N) was applied at three application rates: 15, 30 and 45 m3/ha using a band spread application technique. The LPM was used in combination with reduced and recommended inorganic N levels; a zero N control was also included. Weather conditions in both seasons were similar with below average rainfall levels in spring followed by above average summer rainfall levels. The zero N control gave lowest CNU levels in both growing seasons (70–88 kg N/ha). Inorganic N application at the reduced and recommended N rates increased CNU levels by approximately 100 kgN/ha and 112 kgN/ha, respectively compared to the untreated control. Liquid pig manure application resulted in an additional crop uptake of 58 kgN/ha. Nitrogen use efficiencies for LPM ranged from 23 to 56% while inorganic N use efficiency levels were higher ranging from 58 to 73%. Lowest grain yield levels were measured from the zero N control (range 3.95–5.01 t/ha). The application of inorganic N increased grain yield levels by a minimum of 4.05 t/ha with LPM usage increasing grain yield levels by an additional 0.2–1.09 t/ha. This study showed that LPM could be successfully used in combination with inorganic fertilisers for the improved N nutrition of winter wheat in spring as part of an integrated nutrient programme.  相似文献   
12.
13.
Growth-hormone deficiency in man: an isolated, recessively inherited defect   总被引:3,自引:0,他引:3  
A deficiency of human growth hormone not associated with other pituitary deficiencies was observed in midgets with sexual ateliosis, a form of dwarfism inherited as an autosomal recessive trait. Body proportions, sexual development, birth weight, and postpartum lactation are normal in this syndrome.  相似文献   
14.
An immunosuppressive factor(s) which is heat stable, and dialysable, with a molecular weight less than 10,000 molecular weight, and is not species specific, has been shown to be produced during the in vitro culture of Onchocerca gibsoni microfilariae. The factor(s) is capable of abolishing lymphocyte mitogenesis induced by Con A in bovine lymphocytes and PHA in human lymphocytes. The factor(s) may play a role in establishing the microfilariae in the tissues of the host by depressing cell mediated immune reactions during invasion.  相似文献   
15.
16.
Results from studies performed by the authors and by other workers, have greatly increased the knowledge of canine parvovirus.

The authors review the situation with particular reference to virology, epidemiology, pathogenesis, pathology and immunoprophylaxis.  相似文献   
17.
Interest in selection for improved feed efficiency is increasing, but before any steps are taken toward selecting for feed efficiency, correlations with other economically important traits must first be quantified. The objective of this study was to quantify the genetic associations between feed efficiency measured during performance testing and linear type traits, BW, live animal value, and carcass traits recorded in commercial herds. Feed efficiency data were available on 2,605 bulls from 1 performance test station. There were between 10,384 and 93,442 performance records on type traits, BW, animal value, or carcass traits from 17,225 commercial herds. (Co)variance components were estimated using linear mixed animal models. Genetic correlations between the muscular type traits in commercial animals and feed conversion ratio (-0.33 to -0.25), residual feed intake (RFI; -0.33 to -0.22), and residual BW gain (RG; 0.24 to 0.27) suggest that selection for improved feed efficiency should increase muscling. This is further evidenced by the genetic correlations between carcass conformation of commercial animals and feed conversion ratio (-0.46), RFI (-0.37), and residual BW gain (0.35) measured in performance-tested animals. Furthermore, the genetic correlations between RFI and both ultrasonic fat depth and carcass fat score (0.39 and 0.33, respectively) indicated that selection for improved RFI will result in leaner animals. It can be concluded from the genetic correlations estimated in this study that selection for feed efficiency will have no unfavorable effects on the performance traits measured in this study and will actually lead to an improvement in performance for some traits, such as muscularity, animal price, and carcass conformation. Conversely, this suggests that genetic selection for traits such as carcass quality, muscling traits, and animal value might also be indirectly selecting for more efficient animals.  相似文献   
18.

Background

Early recognition of left‐sided congestive heart failure (CHF) in dogs with degenerative mitral valve disease (DMVD) is important because it influences medical therapy, timing of follow‐up, and outcome.

Hypothesis

Pulmonary vein diameter‐to‐pulmonary artery diameter ratio (PV/PA) measured by echocardiography can predict CHF.

Animals

Ninety‐eight client‐owned dogs, 37 controls, and 61 dogs with DMVD.

Methods

Prospective clinical cohort study. History, physical examination and Doppler‐echocardiography were performed. Dogs were classified as International Small Animal Cardiac Health Council class I, II or III. Congestive heart failure was identified in a subset of 56 dogs based on radiographic findings. The PV/PA was measured in bidimensional (2D) and M‐mode by 2 investigators blinded to the radiologists’ conclusions.

Results

Interobserver coefficients of variation for PV/PA acquisition and measurement were <10%. The PV/PA in control dogs was approximately 1 and increased with class of heart failure. The presence of CHF could be best predicted by measuring PV/PA in 2D echocardiography (cut‐off, 1.7; area under the curve, 0.98; CI, 0.97–0.98; P < .001) with a sensitivity of 96% and a specificity of 91%.

Conclusion and clinical importance

The PV/PA is a simple and reproducible echocardiographic variable that increases with class of heart failure and may help discriminate dogs in CHF from asymptomatic dogs with DMVD. Additional studies are required to determine whether PV/PA might provide additional information in the integrated interpretation of Doppler‐echocardiographic indices of left ventricular filling pressures and could be used for rapid assessment of CHF in dogs in a critical care setting.  相似文献   
19.

Introduction

Serotonin (5-hydroxytryptamine [5-HT]) has several biological functions. In different species, excessive 5-HT has been linked to valvular lesions, similar to those seen in dogs with myxomatous mitral valve disease. Previous studies suggest higher 5-HT in healthy Cavalier King Charles Spaniels (CKCSs), a breed highly affected by myxomatous mitral valve disease, compared to other breeds.

Objective

To investigate potential interbreed variation in serum 5-HT in healthy dogs.

Animals

483 healthy dogs of nine breeds aged 1–7 years.

Methods

Dogs were examined at five European centers. Absence of cardiovascular, organ-related, or systemic diseases was ensured by thorough clinical investigations including echocardiography. Serum was frozen and later analyzed by enzyme-linked immunosorbent assay (ELISA).

Results

Median 5-HT concentration was 252.5 (interquartile range = 145.5–390.6) ng/mL. Overall breed difference was found (p<0.0001), and 42% of pairwise breed comparisons were significant. Univariate regression analysis showed association between serum 5-HT concentration and breed, center of examination, storage time, and sex, with higher 5-HT in females. In multiple regression analysis, the final model had an adjusted R2 of 0.27 with breed (p<0.0001), center (p<0.0001), and storage time (p=0.014) remaining significant. Within centers, overall breed differences were found at 3/5 centers (p≤0.028), and pairwise comparisons within those centers showed breed differences in 42% of comparisons. Among the included breeds, Newfoundlands, Belgian Shepherds and CKCSs had highest 5-HT concentrations.

Conclusions

Interbreed variation in serum 5-HT concentration was found in healthy dogs aged 1–7 years. These differences should be taken into account when designing clinical studies.  相似文献   
20.
Barley/cereal yellow dwarf viruses (YDVs) cause yellow dwarf disease (YDD), which is a continuous risk to cereals production worldwide. These viruses cause leaf yellowing and stunting, resulting in yield reductions of up to 80%. YDVs have been a consistent but low‐level problem in European cereal cultivation for the last three decades, mostly due to the availability of several effective insecticides (largely pyrethroids and more recently neonicotinoids) against aphid vectors. However, this has changed recently, with many insecticides being lost, culminating in a recent European Union (EU) regulation prohibiting outdoor use of the neonicotinoid‐insecticide compounds. This change is coupled with the growing challenge of insecticide‐resistant aphids, the lack of genetic resources against YDVs, and a knowledge deficit around the parameters responsible for the emergence and spread of YDD. This means that economic sustainability of cereal cultivation in several European countries including France and United Kingdom is now again threatened by this aphid‐vectored viral disease. In this review, we summarize the current knowledge on the YDV pathosystem, describe management options against YDD, analyse the impacts of the neonicotinoid ban in Europe, and consider future strategies to control YDV. © 2020 Society of Chemical Industry  相似文献   
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