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81.
Effects of replacing fish meal with soy cake in a diet based on urea-treated rice straw on performance of growing Laisind beef cattle 总被引:1,自引:1,他引:0
Duong Van Nhiem Jan Berg Nils Petter Kjos Nguyen Xuan Trach Bui Quang Tuan 《Tropical animal health and production》2013,45(4):901-909
The present study was to test if different ratios of fish meal to soy cake as protein supplements in the diet are not significantly different in effects on feed intakes and performance of growing beef cattle fed urea-treated rice straw (URTRS) as basal diet under local conditions in North Vietnam. Thirty-six male cattle of Laisind (50 % local Yellow cattle and 50 % Sindhi, both Bos indicus) at around 12 months of age with an average live weight of 124?±?12 kg at start were used in six groups of the experiment. Six diets named A, B, C, D, E, and F used in the experiment were similar in crude protein (CP) level, except for diet A with no supplementation, but different in fish meal/soy cake ratio based on CP content as follows: diet A 0/0, diet B 100/0, diet C 75/25, diet D 50/50, diet E 25/75, and diet F 0/100. Following a 4-week adaptation period, a comparison period lasted 24 weeks. The total intakes of dry matter (DM), DM from roughage, metabolizable energy (ME), and CP were 6, 7, 6, and 20 % higher in diets B–F than diet A with P values ≤0.05, 0.05, 0.05, and 0.001, respectively. The average daily gain (ADG) was 50 % higher (P?<?0.001) in diets B–F than that in diet A. Compared to diet A, diets B–F had lower feed conversion ratio (FCR)DM, FCRME, and FCRCP by 30, 20, and 30 %, respectively (all at P?<?0.001). There were no significant differences between diets B–F in the intakes, FCRs, and ADG. The apparent digestibility of CP was 12 to 24 % higher (P?<?0.001) in diets B–F than that in diet A. There was a tendency that the apparent digestibilities of DM, CP, and CF were increasing with increasing level of soy cake in this study. The ratio of fish meal to soy cake did not significantly affect feed intakes, ADG, FCR, and apparent nutrient digestibilities of the cattle. Soy cake can therefore be used to partially or fully replace fish meal as a protein supplement in the diet of growing beef cattle fed URTRS without any negative effects on animal performance. 相似文献
82.
A nitrile hydratase (NHase) that specifically accepts the nitrile aeroplysinin-1 (1) as a substrate and converts it into the dienone amide verongiaquinol (7) was isolated, partially purified and characterized from the Mediterranean sponge Aplysina cavernicola; although it is currently not known whether the enzyme is of sponge origin or produced by its symbiotic microorganisms. The formation of aeroplysinin-1 and of the corresponding dienone amide is part of the chemical defence system of A. cavernicola. The latter two compounds that show strong antibiotic activity originate from brominated isoxazoline alkaloids that are thought to protect the sponges from invasion of bacterial pathogens. The sponge was shown to contain at least two NHases as two excised protein bands from a non denaturating Blue Native gel showed nitrile hydratase activity, which was not observed for control samples. The enzymes were shown to be manganese dependent, although cobalt and nickel ions were also able to recover the activity of the nitrile hydratases. The temperature and pH optimum of the studied enzymes were found at 41 °C and pH 7.8. The enzymes showed high substrate specificity towards the physiological substrate aeroplysinin-1 (1) since none of the substrate analogues that were prepared either by partial or by total synthesis were converted in an in vitro assay. Moreover de-novo sequencing by mass spectrometry was employed to obtain information about the primary structure of the studied NHases, which did not reveal any homology to known NHases. 相似文献
83.
Daniela Blecker Nils Hiebert Franziska Kuhne 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(3):170-174
Revealing why pedestrians are afraid of some dogs while passing them in public is essential to assess the dog–owner–stranger relationship. Therefore, the effect of different dog features on passersby was gathered. Four dog features differing in size and color were investigated. The dog features were classified as small-dark, small-pale, large-dark, and large-pale. Dog's effect on passersby was recorded in 2 ways: (1) observing the behavioral responses of passersby while passing nearby a dog, and (2) revealing the passersby's perception of that dog by a short interview. Direct observations of 427 passersby's behavioral responses while passing a dog on a sideway were acquired, and 126 persons were interviewed. It was suggested that large-dark dogs seemed to be more threatening than pale or small dogs. Passersby confronted with pale dogs of equal size changed their way far less than when confronted with dark dogs. Significant differences were noted for the type of effect assessed and the reason for this behavioral response. The results showed that only the small-pale dog appeared to be friendly because of its size (P = 0.000). All other dogs were stated as friendly because of individual factors including breed and own dog experiences (P = 0.000). None of the dogs were mentioned as threatening. Our results show that some dog features have a significant effect on behavioral responses and the subjective perception of dogs by people in public. 相似文献
84.
Kevin A Glover Tore Haug Nils Øien Lars Walløe Lotta Lindblom Bjørghild B Seliussen Hans J Skaug 《Fish and Fisheries》2012,13(3):313-332
The application of genetics for the management of natural resources is expanding, and within this field, DNA registers will play an increasing role. The Norwegian minke whale DNA register, established in 1996, was designed primarily as a control system to detect any attempts at illegal trade of products derived from other stocks of minke whale, or other whale species, under cover of the legal Norwegian harvest originating from the Northeast Atlantic. The register contains genetic data for 7644 of 7751 whales landed in the period 1997–2010. Profiles are established from sequencing part of the mtDNA control region, analysis of 10 STRs and a sex‐determining marker. Probabilities of genotypes matching between two randomly selected whales are 6.0?04 and 3.0?08 for five and eight of the STR loci, respectively. This permits verification of traded whale products via match to the register. The register has also been used in a number of ad hoc scientific studies resulting through the accumulation of genetic, demographic and biological data. Here, we review the register’s logistics, specifications and evaluate the potential to apply similar registers to control the exploitation of other marine species. 相似文献
85.
Linda J Keeling Anna Wallenbeck Anne Larsen Nils Holmgren 《Acta veterinaria Scandinavica》2012,54(1):32
Background
There is increasing interest in recording tail damage in pigs at slaughter to identify problem farms for advisory purposes, but also for benchmarking within and between countries as part of systematic monitoring of animal welfare. However, it is difficult to draw conclusions when comparing prevalence’s between studies and countries partly due to differences in management (e.g. differences in tail docking and enrichment routines) and partly due to differences in the definition of tail damage.Methods
Tail damage and tail length was recorded for 15,068 pigs slaughtered during three and four consecutive days at two slaughterhouses in Sweden. Tail damage was visually scored according to a 6-point scale and tail length was both visually scored according to a 5-point scale and recorded as tail length in centimetres for pigs with injured or shortened tails.Results
The total prevalence of injury or shortening of the tail was 7.0% and 7.2% in slaughterhouse A and B, respectively. When only considering pigs with half or less of the tail left, these percentages were 1.5% and 1.9%, which is in line with the prevalence estimated from the routine recordings at slaughter in Sweden. A higher percentage of males had injured and/or shortened tails, and males had more severely bitten tails than females.Conclusions
While the current method to record tail damage in Sweden was found to be reliable as a method to identify problem farms, it clearly underestimates the actual prevalence of tail damage. For monitoring and benchmarking purposes, both in Sweden and internationally, we propose that a three graded scale including both old and new tail damage would be more appropriate. The scale consists of one class for no tail damage, one for mild tail damage (injured or shortened tail with more than half of the tail remaining) and one for severe tail damage (half or less of the tail remaining). 相似文献86.
Nils Fahlvik Mattias Berglund Hampus Holmström Urban Nilsson 《Scandinavian Journal of Forest Research》2018,33(4):347-356
The influence of the intensity and timing of precommercial thinning (PCT) on stand development and financial return was studied in Scots pine stands. Functions describing the early development of the stand structure after PCT were developed. The functions were based on 195 plots within 41 PCT experiments in Sweden. The dimension distribution of the established stand was estimated and used as input to the decision support system Heureka, to simulate the stand development until final felling. The studied treatments included PCT to 1000, 2000 and 3000?stems?ha?1 at mean heights of 2, 4 and 6 m. Separate simulations were carried out for different site fertilities. Mean annual volume increment increased with increasing number of stems after PCT whereas the timing of PCT had only a small effect. The land expectation value (LEV) generally decreased with increasing mean height at PCT, primarily because of the increased cost of PCT. LEV decreased with increasing number of stems after PCT at low fertility sites whereas only minor differences were found for PCT to 1000 and 2000?stems?ha?1 at medium and high fertility sites. The general pattern persisted when different scenarios of future timber quality were simulated. 相似文献
87.
High‐throughput development of SSR marker candidates and their chromosomal assignment in rye (Secale cereale L.)
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Shotgun survey sequences of flow‐sorted individual rye chromosomes were data mined for the presence of simple sequence repeats (SSRs). For 787,850 putative SSR loci, a total of 358,660 PCR primer pairs could be designed and 51,138 nonredundant SSR marker candidates were evaluated by in silico PCR. Of the 51,138 SSR primer candidates, 1,277 were associated with 1,125 rye gene models. A total of 2,112 of the potential SSR markers were randomly selected to represent about equal numbers for each of the rye chromosomes, and 856 SSRs were assigned to individual rye chromosomes experimentally. Potential transferability of rye SSRs to wheat and barley was of low efficiency with 4.3% (2,189) and 0.4% (223) of rye SSRs predicted to be amplified in wheat and barley, respectively. This data set of rye chromosome‐specific SSR markers will be useful for the specific detection of rye chromatin introgressed into wheat as well as for low‐cost genetic and physical mapping in rye without the need for high‐tech equipment. 相似文献
88.
Jussi T. ERONEN P. David POLLY Marianne FRED John DAMUTH David C. FRANK Volker MOSBRUGGER Christoph SCHEIDEGGER Nils Chr. STENSETH Mikael FORTELIUS 《Integrative zoology》2010,5(2):88-101
We outline here an approach for understanding the biology of climate change, one that integrates data at multiple spatial and temporal scales. Taxon-free trait analysis, or “ecometrics,” is based on the idea that the distribution in a community of ecomorphological traits such as tooth structure, limb proportions, body mass, leaf shape, incubation temperature, claw shape, any aspect of anatomy or physiology can be measured across some subset of the organisms in a community. Regardless of temporal or spatial scale, traits are the means by which organisms interact with their environment, biotic and abiotic. Ecometrics measures these interactions by focusing on traits which are easily measurable, whose structure is closely related to their function, and whose function interacts directly with local environment. Ecometric trait distributions are thus a comparatively universal metric for exploring systems dynamics at all scales. The main challenge now is to move beyond investigating how future climate change will affect the distribution of organisms and how it will impact ecosystem services and to shift the perspective to ask how biotic systems interact with changing climate in general, and how climate change affects the interactions within and between the components of the whole biotic-physical system. We believe that it is possible to provide believable, quantitative answers to these questions. Because of this we have initiated an IUBS program iCCB (integrative Climate Change Biology). 相似文献
89.
Nico K Michiels Nils Anthes Nathan S Hart Jürgen Herler Alfred J Meixner Frank Schleifenbaum Gregor Schulte Ulrike E Siebeck Dennis Sprenger Matthias F Wucherer 《BMC ecology》2008,8(1):16
Background
At depths below 10 m, reefs are dominated by blue-green light because seawater selectively absorbs the longer, 'red' wavelengths beyond 600 nm from the downwelling sunlight. Consequently, the visual pigments of many reef fish are matched to shorter wavelengths, which are transmitted better by water. Combining the typically poor long-wavelength sensitivity of fish eyes with the presumed lack of ambient red light, red light is currently considered irrelevant for reef fish. However, previous studies ignore the fact that several marine organisms, including deep sea fish, produce their own red luminescence and are capable of seeing it. 相似文献90.
Azaspiracid shellfish poisoning: a review on the chemistry, ecology, and toxicology with an emphasis on human health impacts
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Azaspiracids (AZA) are polyether marine toxins that accumulate in various shellfish species and have been associated with severe gastrointestinal human intoxications since 1995. This toxin class has since been reported from several countries, including Morocco and much of western Europe. A regulatory limit of 160 microg AZA/kg whole shellfish flesh was established by the EU in order to protect human health; however, in some cases, AZA concentrations far exceed the action level. Herein we discuss recent advances on the chemistry of various AZA analogs, review the ecology of AZAs, including the putative progenitor algal species, collectively interpret the in vitro and in vivo data on the toxicology of AZAs relating to human health issues, and outline the European legislature associated with AZAs. 相似文献