Showing papers on "Toad published in 2012"

03. Sexual dimorphism in the forelimb muscles of the Asiatic toad Bufo gargarizans

Abstract: A exhibit a variety of secondary sexual dimorphisms such as body size, vocal apparatus, head dimensions and colouration (Duellman & Trueb, 1986). With regard to muscle dimorphisms, studies have focused on muscles mass (Kirby, 1983; Yekta & Blackburn, 1992; Lee, 2001; Lee & Corrales, 2002; Liao et al., 2012a, b), muscle fibre types and their sizes (Muller et al., 1969; Melichna et al., 1972; Oka et al., 1984; Dorlochter et al., 1994), and muscle isometric contractile properties (Peters & Aulner, 2000; Girgenrath & Marsh, 2003; Clark & Peters, 2006; Navas & James, 2007). Sexual dimorphisms of muscles can for example be associated with sound production (Schmidt, 1965; Kelley, 1986; Emerson & Boyd, 1999) or amplexus (Kirby, 1983), and have been interpreted as the result of sexual selection (Duellman, 1992; Lee, 2001). Previous studies have shown that forelimb muscles involved in amplexus, such as pectoralis series, coracobrachialis series, deltoideus, triceps branchii, extensor carpi radialis, flexor carpi radialis, sternoradialis and abductor indicus longus, are larger and heavier in males than in females. Larger forelimb muscles in males produce enhanced force for amplexing females, and to resist attempted take-overs by competing males (Kirby, 1983; Oka et al., 1984; Duellman, 1992; Yekta & Blackburn, 1992; Peters & Aulner, 2000; Lee, 2001; Clark & Peters, 2006; Navas & James, 2007; Liao et al., 2012a). These muscles are also less fatigable in males than in females, which may allow male frogs to maintain amplexus for prolonged periods (Peters & Aulner, 2000; Clark & Peters, 2006; Navas & James, 2007). However, forelimb muscles not involved in amplexus have not received much attention so far. In this study, I compared the mass of forelimb muscles between males and females depending on whether they are used during amplexus, considering amplectant and non-amplectant males. The Asiatic toad, Bufo gargarizans, is widely distributed in China, Russia and Korea (Fei & Ye, 2001). In Nanchong City, the species hibernates in midNovember, and reproduction takes place in December or January (Yu et al., 2009). It is an explosively breeding species, with a breeding season lasting 6–24 days (Yu & Lu, 2010). Males do not discriminate potential mates with respect to body size (Yu & Lu, 2010). The aims of the present study are to: (i) Quantify the differences in body size and mass of selected forelimb muscles between female and male B. gargarizans; (ii) Compare body size and selected forelimb muscles mass between amplectant and non-amplectant males.

Decline and flounder of a Sussex common toad (Bufo bufo) population

Abstract: Common toads Bufo bufo have declined over much of southern and eastern England in recent decades where other widespread amphibian species have remained relatively stable. One such toad decline, at Offham marshes in Sussex, was investigated over the fifteen year period 1998-2012 immediately subsequent to a tenfold decrease in population size between 1989 and 1997. Syntopic amphibians (Rana temporaria, Lissotriton vulgaris and L. helveticus) probably also declined at this site. The surviving toad population continued to recruit new cohorts and had an apparently healthy age structure. Habitat quality (aquatic and terrestrial) remained good and there was no evidence of disease. An invasive species (Pelophylax ridibundus) was excluded as a likely cause of toad decline. However, traffic on a neighbouring road rendered more than half the previously available terrestrial habitat for toads essentially unreachable. Furthermore, reduced management of vegetation in ditches where the toads breed apparently increased mortality of developing tadpoles. Future prospects for conserving and increasing the toad population are discussed.

Application of toad cake to preparation of medicament for suppressing biosynthesis of oleic acid (OA) and linoleic acid (LA)

Abstract: The invention provides an application of a toad cake to preparation of a medicament for suppressing biosynthesis of oleic acid (OA) and linoleic acid (LA). In a toad cake administration group animal, the metabolic level of AA (Arachidonic Acid) rises, and the metabolic levels of LA and OA fall, which indicate that the toxic and side effects of the toad cake can be used for suppressing the biosynthesis of LA and OA. Metabolic disorder of AA greatly influences normal functions of a heart, can cause reduction in the contraction force of the heart and reduction in cardiac output and can even induce or aggravate myocardial infarct and angina pectoris. By suppressing the biosynthesis of LA and OA through the toad cake, the content of the toad cake in a medicament can be adjusted reasonably, and heart diseases can be better treated or prevented.

Preparation method of Cordyceps-toad skin composition

Abstract: The invention discloses a preparation method of a Cordyceps-toad skin composition. The method is characterized by: spreading a fresh toad skin exuviated from a toad in an appliance, then scattering Cordyceps powder evenly on the fresh toad skin, which is placed in a dry and ventilated place and dried in the air, then placing the toad skin in a drying box and drying it for 1-10 hours, or exposing it to ultraviolet rays for 1-10 hours so as to make the water content less than or equal to 5%, and finally carrying out sterilization as well as disinfection, thus obtaining the Cordyceps-toad skin composition. The invention has the advantages that: the preparation process is simple, the obtained composition is the fresh toad skin, the effective components of which can avoid suffering destruction, and the original drug properties of the toad are retained; and the composition is chewable and can be taken orally, and is easily absorbed by the human body, thus achieving a good treatment effect.

Size, temporal and spatial dynamics of a natterjack toad (bufo calamita) population

Abstract: Abstract The breeding season of the natterjack toad (Bufo calamita Laurenti 1768), a „prolonged breeder“, lasts up to three months in southern Sweden. However, not all reproducing individuals are present at the breeding sites during the full time span. Thus, some populations can be sub-divided into temporally isolated subpopulations using earlier or later periods of the season for reproduction. The aim of this Capture-Mark-Recapture (CMR) study on male toads was the investigation of three contiguous Bufo calamita populations in southern Sweden concerning potential temporally isolated subpopulations within each site, spatial isolation of each site from the others, the total population size compared to former estimations and differences among the three groups between the patterns of presence at the breeding sites. While there was strong evidence for spatial isolation (no migration between the sites could be observed), no clearly isolated temporal groups could be detected (high individual overlap between groups breeding earlier and later during the season). The detected different patterns of presence can be attributed to different age classes being present at the sites respectively, according to body length and weight comparison. CMR based calculations reveal more accurate population size estimates (between 94 and 104 individuals in total) than spawn string or calling counts from earlier monitoring of this area. As the maximum number of male individuals observed during one night (41 ind.) is consideably higher than the counts of former years (20-25 ind.) a population growth can be assumed. Popular science summary: The size and the spatial and temporal dynamics of a Swedish natterjack toad (Bufo calamita) population Introduction Natterjack toads show a characteristic breeding behaviour: (A) Firstly, they are prolonged breeders, which means that – in contrast to many other amphibians' – their breeding season is several months long (in Sweden from April till July). During the season, there are several shorter periods of high calling and mating activity and quiet periods without activity in between. Individual male toads are present during several nights, whereas females just appear at the breeding sites for mating and disappear after one or two nights. However, some studies suggest that not all males stay for the whole breeding season. Thus, it is possible to subdivide them into categories of “early” and “late breeders”. (B) Secondly, there is often a spatial connection between neighbouring natterjack toad populations, built by migrating individuals. Individual toads are known to overcome more than 1000 meters between their breeding habitats. This is an investigation of a natterjack toad population in Revinge, 17 km east of Lund, concerning the properties mentioned above and concerning their population size, using a capture-markrecapture approach. Methods The breeding pools at the 3 different sub-sites of the study area were checked for male toads in 41 nights between late April and the middle of July 2012. Encountered male toads were tagged with PIT tags. That way it was possible to record the individuals' presence and absence at the breeding pools throughout the season. Body length and body mass, mating and calling activity were noted if possible. Results (A) Different peaks of calling and breeding activity as well as longer periods without any toad activity could be observed. This fluctuation can be explained by environmental factors, mainly temperature and rainfall. In June, almost all of the pools fell dry before rain filled some of them up again in late June. This suggests a separation of the season into an “early” period between late April and late May and a “late” period in late June and July. Most of the tagged individuals were either encountered only during the early period (43–56% at the different subsites) or during both periods (30–43%). Only 8–15% were encountered exclusively during the late period. Additionally, if a toad attended the breeding site during the late period was not dependent on if it had attended it during the early period and vice versa. (B) No migration between the three sub-sites could be detected. However, toads from one of the sub-sites accessed a new breeding pool in a distance of 600 metres, which is almost as long as the distance between two of the sub-sites. The population size was estimated between 94 and 104 individuals for the whole area (site 1: 25–29 ind.; site 2: 22–26; site 3: 46–49). Discussion (A) The hypothesis of a clear separation between early and late breeders could not be confirmed due to the high overlap between the two periods. However, as individuals tend to skip breeding in some years, further (long-term) investigation is needed to conclude more details. (B) The fact that the toads established a new breeding pool in a distance of 600 metres shows that they are willing and able to overcome such distances if necessary. That no migration could be detected might be due to the limitation on male toads in this study. Females are known to migrate more frequently between different sites, especially on a long-term scale. Earlier estimations of the population size, based on chorus counts and the maximum number of individuals observed during one night generated much lower numbers. The comparison of the total number of individuals present during one night in 2010 and 2011 (15–30 ind.) to the maximum number of encountered individuals in 2012 (41 ind.) suggests an increase of the population size. However, the results of the capture-mark-recapture method suggest that the number of breeding males was severely underestimated by formerly used approaches. Population size estimation, knowledge about breeding behaviour and population dynamics are of great importance for monitoring purposes. The results of this study are a basis for future observations of this population in the Revinge area. Especially the inclusion of data about females are required to get a full overview on population dynamics. Master's Degree project (30 credits) in General Biology Department of Biology, Lund University Supervisor: Jon Loman

Effect of strong magnetic field stimulation on the animal cardiomuscle

Abstract: Make the low frequency high energy magnetic field stimulate the hearts of amphibian toad and mammalian rat and rabbit. Compare the different Biological effects of the Magnetic Stimulation on different species of animals. Research shows that the animal hearts contracting amplitude restored after stimulated by the low frequency high energy magnetic field. There is a greater effect on the lower animals. The heart rhythmic pulsatile cycle of toad, rat and rabbit were not change.