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1.
Sugar beet vinasse, originating as the condensed molasses residue from yeast production, was fed to bulls and pigs to determine the feed value. It contained, per kg dry matter (DM content 66.8%), 293 g crude protein, 305 g N-free extract (therefrom 34.4 g total sugar), and 395 g crude ash. The experiment was carried out with three fattening bulls (German Holstein) and four adult pigs (Gottingen Minipig). In bulls, two balance trials lasting 20 days each (10 days adaptation; 10 days collection) were conducted in which subsequently a basal ration without and with vinasse (14% in DM) was fed. In pigs, the experiment consisted of three 12-day balance trials with the final 5 days as collection period. In the first trial, pigs received a basal diet without vinasse and in the following, a mixed diet with 16 and 43% vinasse (in DM) respectively. Digestibilities of components in vinasse in bulls were: organic matter 73.5%, crude protein 72.6%, and N-free extract 52.3%. In bulls, no influence on faeces quality could be detected while feeding 14% vinasse in DM. While feeding 16% vinasse in DM to pigs, the digestibility of organic matter amounted to 72.3% (crude protein 71.8%; NfE 74.6%). Feeding higher amounts of vinasse (43% in DM) in the diet of pigs, digestibilities were reduced (organic matter: 61.6%), which might be a result of a reduced retention time of the chyme as a result of an osmotically driven diarrhoea because of unexpectedly high sulphate (136 g/kg DM) content in the vinasse. It is concluded that because of organic matter digestibility >70% for cattle and pigs, the use of vinasse in these species in small proportions is reasonable.  相似文献   
2.
The presence of virulent Newcastle disease virus (NDV) since the 1993-94 epidemic in southern Africa holds major implications for the export of ostrich products from this region. A challenge experiment with this field strain was conducted in open-air feedlot facilities under strict biosecurity measures. The experiment was designed to follow vaccination and preslaughter quarantine regulations currently enforced in South African export ostrich facilities in order to determine the viremia period and immune response under these specific circumstances. One hundred forty-three slaughter ostriches were allocated into three test groups, according to the time period between pretrial vaccination and challenge (1-2 mo, 2-4 mo, 4-6 mo), and an unchallenged control group. All birds in the test groups were challenged by oral, tracheal, and ocular routes with a field isolate of NDV. They were slaughtered over the next 4 wk on nine separate occasions and bled on 12 occasions. Virus isolation was attempted from seven sets of pooled samples from each bird to determine the viremia period and the serum antibody concentrations were measured by hemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA) methods to establish an immune response curve. NDV could be back-isolated only up to day 9 postinfection and from only six ostriches with poor immune response titers and corresponding to a rise in antibody levels above an indirect ELISA optical density reading of 0.33. Virus could be recovered only from brain and respiratory tract tissue. The HI test was less sensitive than the ELISA. Immune response curves did not differ significantly between the groups and peaked on day 14 post-infection. From these data, ELISA titers would appear to be a good indicator of the probability that an ostrich will be clinically infected after velogenic NDV challenge. These results also suggest that the current vaccination schedule enforced by the South African Veterinary Authorities results in protective immunity in up to 95% of slaughter ostriches from export approved facilities. The standard 30-day preslaughter quarantine period introduced as part of Crimean-Congo hemorrhagic fever virus control measures also appears sufficient to encompass the determined NDV viremia period of 9-11 days in slaughter ostriches.  相似文献   
3.
When large numbers of crocodile skins were downgraded because of the presence of small pin prick-like holes, collapsed epidermal cysts were found deep in the dermis of juvenile crocodiles while forming cysts were observed in hatchlings. Histopathology of these forming cysts showed the presence of intracytoplasmic inclusions in proliferating and ballooning epidermal cells. Pox virions were seen in electron microscope preparations made from the scabs of such early lesions. The partial sequencing of virus material from scrapings of these lesions and comparison of it with the published sequence of crocodile poxvirus showed the virus associated with the deep lesions to be closely related, but different. To differentiate between the two forms of crocodile pox infection it is suggested that the previously known form should be called "classical crocodile pox" and the newly discovered form "atypical crocodile pox". The application of strict hygiene measures brought about a decline in the percentage of downgraded skins.  相似文献   
4.
ABSTRACT

The corn-grass intercropping system began to be used in the dry season, as it provides increased straw production for the no-tillage system. However, corn and grass are plants demanding in nitrogen. The corn cultivated in the dry season is called out-of-season corn in Brazil. The objective of this study was to evaluate the productivity and nutrients concentrations of out-of-season corn and Congo-grass intercropped in the no-tillage system, as a function of the nitrogen rates applied in sidedressing. The treatments were four nitrogen rates, 0, 30, 60 and 90?kg?ha?1. The experimental design was randomised complete blocks with four replicates. The experimental period corresponded to the harvests of 2015 and 2016. There were evaluated: corn grain yield, dry mass production and nutrient concentration in the shoots of the plants intercropped. The evaluations were carried out at the physiological maturity stage of the corn and at the time of desiccation of the grass. Nitrogen increased grain yield and dry mass production of the plants intercropped. Nitrogen maximised the magnesium concentration in out-of-season corn and the nitrogen, calcium, magnesium and sulphur concentrations in Congo grass. Excess nitrogen promoted reduction of the phosphorus in the Corn-Congo grass intercropping system in the dry season.  相似文献   
5.
Objective-To determine whether partial transection of the medial branch of the suspensory ligament (MBSL) alters equine third metacarpal bone (MC3) condylar surface strains and forelimb, distal joint angles in a manner consistent with promotion of lateral condylar fracture. Study Design-In vitro biomechanical experiment. Sample Population-Right forelimbs from 7 Thoroughbred horse cadavers. Methods-Lateral and medial MC3 condylar, dorsal and abaxial, bone surface strains and distal joint angles were measured both before and after partial transection of the MBSL during in vitro axial limb compression. Dorsal, principal bone strains and abaxial, uniaxial, and proximodistal strains were compared before and after MBSL partial transection at 1,400-, 3,000-, and 5,600-N loads. Results-Bone strains increased in all locations with increasing axial load. All lateral condylar bone strains were significantly higher, and abaxial surface medial condylar bone strain was significantly lower, after partial transection of the MBSL. Respective distal joints became more flexed or extended as axial load increased but were not significantly different after partial transection of the MBSL. Conclusions-Partial transection of the MBSL increases in vitro MC3 lateral condylar bone surface strains. Clinical Relevance-Loss of integrity of the medial branch of the suspensory ligament could increase the risk for lateral condylar fracture in Thoroughbred horses by amplifying bone strain in the lateral condyle.  相似文献   
6.
7.
Lumpy skin disease (LSD) is a highly infectious disease of cattle caused by a virus belonging to the Capripoxvirus genus of the family Poxviridae. The purpose of this study is to place on record the first confirmation of LSD in the Sultanate. The disease was diagnosed and confirmed using polymerase chain reaction, histopathology, transmission electron microscopy and serum neutralization testing. The epizootic occurred in 2009 involving a large number of animals and covering a wide area including Nezwa, Alqabel, Sohar, Saham and Burimi. Morbidity and mortality rates of 29.7 and 26.3 %, and 13.6 and 15.4 % were observed at Nezwa and Sohar, respectively. The clinical signs were much more severe in Holstein–Friesian cattle compared to indigenous breeds and were characterized by multiple skin nodules covering the neck, back, perineum, tail, limbs and genital organs. Affected animals also exhibited lameness, emaciation and cessation of milk production. Oedema of limbs and brisket, and superficial lymph node enlargement were highly prominent. It is not known from where the virus originated, or how it spread to the Sultanate. The disease has become endemic in the country and is liable to extend to other Gulf Cooperation Council Countries and cause a pandemic. It is of major concern to the Omani dairy industry. Due to the widespread presence of screw worm, serious economic losses can follow outbreaks.  相似文献   
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9.
Malignant hyperthermia (MH) is a pharmacogenetic disorder of skeletal muscle. In genetically susceptible pigs, MH can be induced by volatile, halogenated anaesthetics such as halothane. Within a series of pharmacological investigations, a fulminant MH could be induced in 59 of 66 homozygous halothane-susceptible pigs by a challenge with 3% halothane for 15 minutes. The typical MH was characterized by sudden appearance of tachycardia, muscle rigidity with typical extension of the hindlimbs, increase of body temperature, acidosis-caused by rapid increase of CO2 and lactate production-, hyperkalaemia and increased activity of creatine kinase (CK) and aspartate transaminase (AST). In seven homozygous MH-susceptible pigs, this typical MH could not be induced by halothane. These animals responded with sudden appearance of bradyarrhythmia and decrease of arterial pressure. In these MH-atypical pigs (MHA) neither the typical extension of hindlimbs nor a hyperthermia occurred. Compared to a group of 6 MH-susceptible pigs with typical reactions to halothane (MHS), the biochemical alterations were significantly retarded in MHA-pigs. These atypical reactions to halothane could be the effect of decreased cardiac output. Concerning the atypical reactions, we observed a familiar predisposition in MH-susceptible pigs. Although atypical reactions were not found in a group of homozygous halothane-nonsusceptible pigs (MHN), a possible explanation for atypical reactions could be a MH-independent halothane-susceptibility of the myocardium+ in MHA-pigs. On the other side the data may indicate that a primary defect in both the skeletal muscle and also the myocardium is involved in MH. The different reactions to halothane in MH-susceptible pigs could point to a genetic heterogeneity.  相似文献   
10.
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