cranes Dotaz Zobrazit nápovědu
The red-crowned crane (Grus japonensis) is a vulnerable bird species. Mycotoxins are toxic substances produced by filamentous fungi and are considered as naturally unavoidable contaminants in animal feed. Our recent survey indicated that feeds designed for captive red-crowned cranes were contaminated with mycotoxins. This study was conducted to investigate the protective effects of the mycotoxin binder montmorillonite on the reproductive behavior, sex hormone levels, and egg quality of red-crowned cranes. Twelve pairs of G. japonensis were divided into four groups, and each group was fed one of the following: a selected diet (with extra low levels of mycotoxins), a regular diet, a selected diet with 0.5% montmorillonite added, or a regular diet with 0.5% montmorillonite added. Consumption of the regular diet decreased courtship and mating behaviors, testosterone concentration, egg weight, and shell thickness. However, feed supplementation with montmorillonite increased the courtship, mating behaviors and testosterone concentration during the pre-breeding period, as well as egg weight and shell thickness. These findings suggest that the addition of dietary montmorillonite is effective for controlling mycotoxins in the feed, resulting in improvements in reproductive behaviors, testosterone concentrations, and some egg quality parameters of the red-crowned crane.
- MeSH
- bentonit chemie MeSH
- dieta MeSH
- krmivo pro zvířata analýza normy MeSH
- mykotoxiny analýza toxicita MeSH
- ovum chemie MeSH
- pohlavní steroidní hormony krev MeSH
- ptáci fyziologie MeSH
- rozmnožování účinky léků MeSH
- sexuální chování zvířat účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: The red-crowned crane (Grus japonensis) is one of the most vulnerable bird species in the world. Mycotoxins are toxic secondary metabolites produced by fungi and considered naturally unavoidable contaminants in animal feed. Our recent survey indicated that the mycotoxins had the potential to contaminate redcrowned crane's regular diets in China. OBJECTIVE: This experiment was conducted to investigate the protective effects of mycotoxin binder montmorillonite (Mont) on growth performance, serum biochemistry and oxidative stress parameters of the red-crowned crane. METHODS: 16 red-crowned cranes were divided into four groups and fed one of the following diets; a selected diet, regular diet, or the selected diet or regular diet with 0.5% montmorillonite added to the diets. The cranes' parameters of performance, hematology, serum biochemistry and serum oxidative stress were measured. RESULTS: Consuming regular diets decreased the average daily feed intake (ADFI), levels of haemoglobin (Hb), platelet count (PLT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), but increased the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK) and lactate dehydrogenase (LDH). The supplementation of 0.5% Mont provided protection for the red-crowned crane in terms of feed intake, serum biochemistry and oxidative stress. Moreover, Mont supplementation had no adverse effect on the health of red-crowned crane. CONCLUSIONS: Taken together, these findings suggested that the addition of dietary Mont is effective in improving the health of red-crowned crane.
131 s. : il.
Urban animals and birds in particular are able to cope with diverse novel threats in a city environment such as avoiding novel, unfamiliar predators. Predator avoidance often includes alarm signals that can be used also by hetero-specifics, which is mainly the case in mixed-species flocks. It can also occur when species do not form flocks but co-occur together. In this study we tested whether urban crows use alarm calls of conspecifics and hetero-specifics (jackdaws, Corvus monedula) differently in a predator and a non-predator context with partly novel and unfamiliar zoo animal species. Birds were tested at the Tiergarten Schönbrunn in the city of Vienna by playing back con- and hetero-specific alarm calls and control stimuli (great tit song and no stimuli) at predator (wolf, polar bear) and non-predator (eland antelope and cranes, peccaries) enclosures. We recorded responses of crows as the percentage of birds flying away after hearing the playback (out of those present before the playback) and as the number of vocalizations given by the present birds. A significantly higher percentage of crows flew away after hearing either con- or hetero-specific alarm calls, but it did not significantly differ between the predator and the non-predator context. Crows treated jackdaw calls just as crow calls, indicating that they make proper use of hetero-specific alarm calls. Responding similarly in both contexts may suggest that the crows were uncertain about the threat a particular zoo animal represents and were generally cautious. In the predator context, however, a high percentage of crows also flew away upon hearing the great tit control song which suggests that they may still evaluate those species which occasionally killed crows as more dangerous and respond to any conspicuous sound.
- MeSH
- ptáci MeSH
- velkoměsta MeSH
- vokalizace zvířat * MeSH
- vrány * MeSH
- zvířata v ZOO MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- velkoměsta MeSH
Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal when analyzing interaction network structure, and may lead to erroneous conclusions. We developed practical and reproducible sampling guidelines for the plot-based analysis of arthropod interaction networks in forest canopies. Our sampling protocol focused on insect herbivores (leaf-chewing insect larvae, miners and gallers) and non-flying invertebrate predators (spiders and ants). We quantitatively sampled the focal arthropods from felled trees, or from trees accessed by canopy cranes or cherry pickers in 53 0.1 ha forest plots in five biogeographic regions, comprising 6,280 trees in total. All three methods required a similar sampling effort and provided good foliage accessibility. Furthermore, we compared interaction networks derived from plot-based data to interaction networks derived from simulated non-plot-based data focusing either on common tree species or a representative selection of tree families. All types of non-plot-based data showed highly biased network structure towards higher connectance, higher web asymmetry, and higher nestedness temperature when compared with plot-based data. Furthermore, some types of non-plot-based data showed biased diversity of the associated herbivore species and specificity of their interactions. Plot-based sampling thus appears to be the most rigorous approach for reconstructing realistic, quantitative plant-arthropod interaction networks that are comparable across sites and regions. Studies of plant interactions have greatly benefited from a plot-based approach and we argue that studies of arthropod interactions would benefit in the same way. We conclude that plot-based studies on canopy arthropods would yield important insights into the processes of interaction network assembly and dynamics, which could be maximised via a coordinated network of plot-based study sites.
- MeSH
- členovci fyziologie MeSH
- interakce hostitele a parazita * MeSH
- larva fyziologie MeSH
- lesy MeSH
- rostliny parazitologie MeSH
- stromy parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
10. éd 1256 s. : il.
- Konspekt
- Lékařské vědy. Lékařství
- NLK Obory
- patologie
- chirurgie
