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1.

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.
  相似文献   
2.
Since 2012, a new pathogenic syndrome has frequently been observed in many areas of kiwifruit cultivation in Italy. The main symptoms include an initial withering of the leaves followed by a total and sudden collapse of plants, mainly occurring during summer. The withered leaves fall and the main and secondary feeder roots appear rotten, sometimes showing a reddish-brown discoloration. The disease, that affects both the green and yellow-fleshed cultivars, has been called kiwifruit vine decline and is locally known as moria. The syndrome has been found consistently associated with soil waterlogging, which frequently occurs either after the traditional agronomical practice of irrigating orchards through surface irrigation or after very heavy rainfall. So far, the role played by bacteria in this syndrome has not been investigated. In the present study, Clostridium spp. were isolated from both rotten roots and soils obtained from Italian kiwifruit orchards affected by the syndrome, indicating for the first time that anaerobic bacteria are able to cause damage to woody crops. C. bifermentans and C. subterminale incited symptoms in kiwifruit in both in vivo and in vitro pathogenicity tests. Soil waterlogging seems to potentially favour colonization of kiwifruit roots by anaerobic bacteria, probably because saturation of the soil can facilitate proliferation and persistence of these bacteria during long periods of the vegetative growth of the crop. The occurrence of anaerobic bacteria does not exclude the possibility that other microorganisms can play additional/synergic role(s) in causing the kiwifruit vine decline.  相似文献   
3.
The ring‐tailed coati (Nasua nasua) is a procyonid whose population is in sharp decline. Therefore, studies are needed to better understand the reproduction of this animal. For this reason, this study aimed to evaluate the morphology, morphometry and sperm ultrastructure of ring‐tailed coati sperm. Four captive adult males were used for this study. Slides stained with Bengal Rose were used for the morphometric and morphologic analyses. The length and width of the head were measured, as well as the length of the midpiece and tail and the total length of the sperm. Scanning electron microscopy and transmission electron microscopy were used for the ultrastructural analyses. The most obvious morphological abnormalities observed were coiled tails (6.1 ± 8.7%) and the lack of acrosomes (5.4 ± 4.4%). Regarding the morphometry, the measurements of the head (length × width), midpiece (length) and tail (length) were (mean ± SD) 6.2 ± 0.4 × 8.1 ± 0.6 μm, 14.1 ± 0.5 and 63.9 ± 4.1 μm, respectively, and the total length of the sperm was 86.1 ± 4.3 μm. Through electron microscopy, the presence of electron‐lucent points in the nucleus and the presence of approximately 55 mitochondrial spirals in the midpiece were identified. The data obtained in this study provide detailed information on the sperm characteristics of coatis and may inform future research on germplasm conservation, both for this species and other threatened procyonids.  相似文献   
4.
The interaction of ochratoxin A (OTA) and 20 yeast strains of Saccharomyces cerevisiae and Kloeckera apiculata during alcoholic fermentation was studied. Levels of OTA were determined in the fermentation liquid and in the yeast cells solid using a high-performance liquid chromatography system with a fluorescence detector. Yeast cells do not adsorb OTA, and for all yeasts, OTA levels did not affect the alcoholic fermentation. Some yeast strains reduced levels of OTA, whereas other strains did not show any effect demonstrating that OTA level reduction is not a genus species characteristic but a strain trait.  相似文献   
5.
The effect of footrot on body weight and wool growth of sheep   总被引:1,自引:0,他引:1  
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured.  相似文献   
6.
In this work an HPLC method for the determination of azadirachtin residues on olives was developed, and the field degradation kinetics of the pesticide was studied. In field trials the active ingredient (a.i.) decay had a half-life time of 0.8 days, which was too short to show a good efficacy of treatment. The mechanism of disappearance of the pesticide studied with model systems showed that it was unrelated to evaporation, thermodegradation, and co-distillation, but it was related to photodegradation. The high photodegradation rate of commercial formulations calls for the need to test different formulates in order to increase the persistence of the residue and thus the pesticide's efficacy.  相似文献   
7.
The local effects of isolated magnetic adatoms on the electronic properties of the surface of a superconductor were studied with a low-temperature scanning tunneling microscope. Tunneling spectra obtained near magnetic adsorbates reveal the presence of excitations within the superconductor's energy gap that can be detected over a few atomic diameters around the impurity at the surface. These excitations are locally asymmetric with respect to tunneling of electrons and holes. A model calculation based on the Bogoliubov-de Gennes equations can be used to understand the details of the local tunneling spectra.  相似文献   
8.
Nowadays there is considerable interest in the consumption of alternative crops as potential recipes for gluten-free products production. Therefore, the use of buckwheat for the production of gluten-free pasta has been investigated in the present study. RP-HPLC-ESI-TOF-MS has been applied for the separation and characterization of free and bound phenolic compounds in buckwheat flour and buckwheat spaghetti. Thus, 32 free and 24 bound phenolic compounds in buckwheat flour and spaghetti have been characterized and quantified. To the authors' knowledge, protochatechuic-4-O-glucoside acid and procyanidin A have been detected in buckwheat for the first time. The results have demonstrated a decrease of total free phenolic compounds from farm to fork (from flour to cooked spaghetti) of about 74.5%, with a range between 55.3 and 100%, for individual compounds. The decrease in bound phenols was 80.9%, with a range between 46.2 and 100%. The spaghetti-making process and the cooking caused losses of 46.1 and 49.4% of total phenolic compounds, respectively. Of the total phenolic compounds present in dried spaghetti, 11.6% were dissolved in water after cooking.  相似文献   
9.
Cartap hydrolysis relative to its action at the insect nicotinic channel   总被引:2,自引:0,他引:2  
The insecticide cartap is the bis(thiocarbamate) derivative of 2-(dimethylamino)propane-1,3-dithiol, which on oxidation forms the natural toxicant nereistoxin (NTX) [4-(dimethylamino)-1,2-dithiolane]. Both cartap and NTX are ion channel blockers of the nicotinic acetylcholine receptor (nAChR). Cartap was originally proposed to act only after metabolic conversion to NTX and later suggested to block directly without activation. The present study uses a new approach to differentiate these hypotheses, that is, pH effects on channel-blocking activity and hydrolysis rates. As controls, mecamylamine (the classic channel blocker) and NTX are stable and similar in channel-blocking potency ([(3)H]thienylcyclohexylpiperidine binding assay, honeybee nAChR) at pH 6.1-8.4. In contrast, cartap is >200-fold more effective at pH 7.4 than at pH 6.1, indicating that it undergoes hydrolytic activation. Cartap slowly hydrolyzes to cartap monothiol at pH 6.1 but quickly forms the dithiol and some NTX at pH 7.4. The relationship between potency and hydrolysis products at various pH ranges suggests that cartap dithiol is the most plausible blocking agent.  相似文献   
10.
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