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Infectious diseases frequently have multiple potential routes of intraspecific transmission of pathogens within wildlife and other populations. For pathogens causing zoonotic diseases, knowing whether these transmission routes occur in the wild and their relative importance, is critical for understanding maintenance, improving control measures and ultimately preventing human disease. The Norway rat (Rattus norvegicus) is the primary reservoir of leptospirosis in the urban slums of Salvador, Brazil. There is biological evidence for potentially three different transmission routes of leptospire infection occurring in the rodent population. Using newly obtained prevalence data from rodents trapped at an urban slum field site, we present changes in cumulative risk of infection in relation to age-dependent transmission routes to infer which intra-specific transmission routes occur in the wild. We found that a significant proportion of animals leave the nest with infection and that the risk of infection increases throughout the lifetime of Norway rats. We did not observe a significant effect of sexual maturity on the risk of infection. In conclusion, our results suggest that vertical and environmental transmission of leptospirosis both occur in wild populations of Norway rats.
Within early lambing systems, there is a heavy reliance on concentrate feeding in late pregnancy. Therefore, the possibility of replacing conventional dietary ingredients (e.g. barley, fishmeal) with cheaper by-products, such as sugar beet pulp and brewers grains, is of particular interest. Pelleted distillers barley grains fed with molassed sugar beet nuts have been shown to be a suitable feed for pregnant ewes (Merrell and Hyslop, 1994). However, some health problems have been noted when feeding malt distillers wet grains (Vipond and Lewis, 1993). The objective of this trial was to investigate the effect of feeding grainbeet (a mix of 5 parts brewers grains to 1 part molassed sugar beet pulp) on ewe performance, colostrum production and lamb performance.
Concentrate finishing systems for store lambs often involves a dramatic change in the basal diet as lambs are moved from being managed on, e.g. grass and / or roots to concentrates. If this is done too quickly there is a risk of digestive disturbances leading to acidosis and secondary infections. Hence, the selection of the carbohydrate balance between starch and digestible fibre is crucial as ruminants fed high levels of starch-based concentrates can develop sub-clinical acidosis and liver abscess, leading to decreased voluntary food intake and daily live weight gain (DLWG). The aim of this study was to evaluate two concentrate formulations for effective growth for finishing of Swaledale lambs, one concentrate being starch biased the other digestible fibre biased.
Efficient lamb finishing is geared to reaching market at a specific time, this is done by regulating growth rates – this may involve using different feeds – in this case varying in crude protein content or using different breeds – crossbreds rather than purebreds. The objectives of this trial were to determine the effect of different feed crude protein level on lamb performance of two breed types.
Through the dry period to early lactation the cow goes through a dramatic change in her metabolism. To supply the high energy requirement in early lactation fat supply from the diet and body mobilisation increases substantially. As a result, the liver accumulates fat, the rate of detoxification slows down, ammonia accumulates and there’s a reduced supply of fat, glucose and protein to the udder. This trial was designed to evaluate the response of dairy cows to product called ABN-LiFT a proprietary mixture of B-group vitamins and methyl group donors (rumen protected choline, niacin, vitamin B12, biotin, folic acid and thiamine) designed to reduce the accumulation of triglycerides in the liver and accelerate VLDL export.
Urea is a cheap source of non-protein nitrogen that can be included in ewe diets to meet their increasing demand for protein during late pregnancy. However, its rapid rate of ammonia release results in inefficient utilisation of the nitrogen by rumen microbes. New technology which binds urea with sugar has been developed to reduce the rate of ammonia release (regulated release) in the rumen and increase the efficiency of nitrogen utilisation. The objectives of this work was to evaluate the effects of including a regulated urea release product in the diet of ewes during late pregnancy on ewe and lamb performance.
Concentrate finishing systems for store lambs often involves a dramatic change in the basal diet as lambs are moved from being managed on, e.g. grass and / or roots to concentrates. If this is done too quickly there is a risk of digestive disturbances leading to acidosis and secondary infections. However, the desire of the lamb finisher is to transfer the lambs onto the concentrate diets as quickly as possible and reduce rumen friendly materials such as straw to maximise performance. Yeast products have been shown repeatedly to reduce the production of lactic acid and stimulate the utilisation of lactic acid by certain rumen microflora, e.g. M. elsdenii leading to a more optimal rumen environment for the rumen microflora that in turn enhances nutrient supply and animal performance.
The aim of this trial was to determine whether there would be any response to the inclusion of two yeast products, a live yeast, Yeasacc 1026 and a yeast culture, Diamond V XP, in intensively finished Swaledale wether store lambs.
Intensively reared early weaned lambs are conventionally fed a high energy concentrate diet in order to maximise daily gain and feed conversion efficiency. This reduces both the time required to reach slaughter weight and the overhead costs. However, it is estimated that feed costs in intensive lamb systems amount to 0.24 of the total output value (MLC 1998) and that the profitability is sensitive to relatively small changes in the lamb price to feed cost ratio. The objective of the work was to investigate the effects of various alternative feeds consisting of molassed sugar beet feed (MSBF), distillers products and the whole barley or grainbeet (200 g/kg MSBF and 700 g/kg brewers grain) on the performance and profitability of intensively reared lambs.
Urban slums provide suitable conditions for infestation by rats, which harbour and shed a wide diversity of zoonotic pathogens including helminths. We aimed to identify risk factors associated with the probability and intensity of infection of helminths of the digestive tract in an urban slum population of Rattus norvegicus. Among 299 rats, eleven species/groups of helminths were identified, of which Strongyloides sp., Nippostrongylus brasiliensis and, the human pathogen, Angiostrongylus cantonensis were the most frequent (97, 41 and 39%, respectively). Sex interactions highlighted behavioural differences between males and females, as eg males were more likely to be infected with N. brasiliensis where rat signs were present, and males presented more intense infections of Strongyloides sp. Moreover, rats in poor body condition had higher intensities of N. brasiliensis. We describe a high global richness of parasites in R. norvegicus, including five species known to cause disease in humans. Among these, A. cantonensis was found in high prevalence and it was ubiquitous in the study area – knowledge which is of public health importance. A variety of environmental, demographic and body condition variables were associated with helminth species infection of rats, suggesting a comparable variety of risk factors for humans.
Fieldwork at Rendlesham in Suffolk has identified a major central place
complex of the early–middle Anglo-Saxon periods. This has particular
significance in the light of Bede's eighth-century reference to a ‘royal
settlement’ at Rendlesham and the princely burial site at nearby Sutton Hoo.
This interim report summarises the archaeology, and considers the wider
interpretative issues relating to economic complexity and social
Urban slum environments in the tropics are conducive to the proliferation and the spread of rodent-borne zoonotic pathogens to humans. Calodium hepaticum (Brancroft, 1893) is a zoonotic nematode known to infect a variety of mammalian hosts, including humans. Norway rats (Rattus norvegicus) are considered the most important mammalian host of C. hepaticum and are therefore a potentially useful species to inform estimates of the risk to humans living in urban slum environments. There is a lack of studies systematically evaluating the role of demographic and environmental factors that influence both carriage and intensity of infection of C. hepaticum in rodents from urban slum areas within tropical regions. Carriage and the intensity of infection of C. hepaticum were studied in 402 Norway rats over a 2-year period in an urban slum in Salvador, Brazil. Overall, prevalence in Norway rats was 83% (337/402). Independent risk factors for C. hepaticum carriage in R. norvegicus were age and valley of capture. Of those infected the proportion with gross liver involvement (i.e. >75% of the liver affected, a proxy for a high level intensity of infection), was low (8%, 26/337). Sixty soil samples were collected from ten locations to estimate levels of environmental contamination and provide information on the potential risk to humans of contracting C. hepaticum from the environment. Sixty percent (6/10) of the sites were contaminated with C. hepaticum. High carriage levels of C. hepaticum within Norway rats and sub-standard living conditions within slum areas may increase the risk to humans of exposure to the infective eggs of C. hepaticum. This study supports the need for further studies to assess whether humans are becoming infected within this community and whether C. hepaticum is posing a significant risk to human health.
Mozambique “switched from a pro-Chinese to a pro-Soviet stance during the Angolan civil war,” writes a commentator in the influential U.S. quarterly Foreign Policy of Fall 1977. “Mozambique said to Cool on Soviets, Turn West,” headlines a Washington Post dispatch of December 15, 1977. The Economist’s Foreign Report claims in its advertising to have been the first to describe the ideological infighting within FRELIMO and the swing to Russia. The commentators seemed to have missed Mozambique’s 1977 trade fair in September, at which the People’s Republic of China won first prize for an exhibit corresponding to Mozambique’s needs, but if they had been there one might well have seen headlines proclaiming Mozambique’s shift back to China.
The observed properties of the diffuse ionized gas (DIG) in our Galaxy are not easily reconcilable with simple photoionization models. This suggests that there are different or additional physical processes at work in the DIG. We have developed a model of the DIG whereby it is ionized by a relatively soft ionizing spectrum (Teff ≤ 32,000 K) and is also heated by an additional thermal mechanism: the dissipation of turbulence. This model predicts the same electron temperature, [N II] λ 6583/Hα ratio, [S II] λ 6716/Hα ratio and He I λ 5876/Hα ratio as observed in the DIG. Without the turbulent thermal heating term, this model will not reproduce the observed properties of the DIG. The dissipation of turbulence may also be important in other phases of the ISM.
Bhat et al. (1998) presented a model in which they explain the increase in scintillation bandwidth with decreasing pulsar distance as being due to a shell of scattering material associated with the Local Bubble. However, Britton et al. (1998) concluded that the scattering material for local pulsars is nearer to the pulsar (i.e. possibly in a bow shock or shell near the pulsar). We have investigated the effects of the local bubble shell and pulsar bow shocks on the scintillation bandwidth, the scintillation timescales and the angular broadening of pulsars. We find that a) there is no evidence for a shell of scattering material associated with the Local Bubble because the scintillation timescale data do not fit the Bhat et al. model and the angular broadening measurements do not suggest a scattering screen near the Sun, and b) that pulsar bow shocks cannot produce any enhanced scintillations.
Space Very Long Baseline Interferometry observations of PSR 0329+54 which, by luck, occurred during an interstellar fringing event, are presented. Separate images of the pulsar were not detected. However, the pulsar was observed to be extended. The size of PSR 0329+54 during this event is 1.88 × 1.67 mas with a position angle of 30° East of North. This could be due to two separate images of the pulsar separated by ∆θ ≲ 0.5 mas or angular broadening. The observed image size is larger than the expected angular broadening size of < 0.1 mas from the observations of Britton, Gwinn and Ojeda (1998).
Smith’s Cloud is a large few × 106 Solar Mass cloud which will impact the Milk Way disk in about 35 Million Years (Lockman et al., 2008). Green Bank Telescope OH observations indicate that there are no molecules present in Smith’s Cloud, and thus there is no active ongoing chemistry in Smith’s Cloud.
We report herein the investigation of a leptospirosis outbreak occurring in triathlon competitors on Réunion Island, Indian Ocean. All participants were contacted by phone or email and answered a questionnaire. Detection and molecular characterization of pathogenic Leptospira was conducted in inpatients and in rodents trapped at the vicinity of the event. Of the 160 athletes competing, 101 (63·1%) agreed to participate in the study. Leptospirosis was biologically confirmed for 9/10 suspected cases either by real-time PCR or serological tests (MAT or ELISA). The total attack rate, children's attack rate, swimmers’ attack rate, and the attack rate in adult swimmers were respectively estimated at 8·1% [95% confidence interval (CI) 4·3–14·7], 0%, 12·7% (95% CI 6·8–22·4) and 23·1% (95% CI 12·6–33·8). Leptospirosis cases reported significantly more wounds [risk ratio (RR) 4·5, 95% CI 1·6–13], wore complete neoprene suits less often (RR 4·3, 95% CI 1·3–14·5) and were most frequently unlicensed (RR 6·6, 95% CI 2·9–14·8). The epidemiological investigation supported that some measures such as the use of neoprene suits proved efficient in protecting swimmers against infection. PCR detection in rats revealed high Leptospira infection rates. Partial sequencing of the 16S gene and serology on both human and animal samples strongly suggests that rats were the main contaminators and were likely at the origin of the infection in humans.