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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Sound Production of the Spotted Catfish (Arius maculatus) in Cigu lagoon, Tainan, Taiwan

Lin, Szu-Ying 03 September 2010 (has links)
According to earlier surveys, there were nine sound types in areas adjacent to the estuaries of nine major rivers in Taiwan, and the frequency range of the H-type sound was as high as 6 kHz. The producers of this sound type have not been defined yet. Sea catfish can make two kinds of sounds: stridulatory sound and drumming sound. The former is pulsed, broad-band and high-frequency, whereas the latter is harmonic, and low-frequency (less than 1 kHz). Spotted catfish (Arius maculates) is the most common demersal species in the west coast of Taiwan. The aims of the study were (1) to find out if H-type sound is presence in Cigu lagoon; (2) to describe the disturbance (hand-held) sounds emitted by A. maculates; (3) to find clues to support that the stridulatory sound of A. maculates is the H-type sound; (4) to find if there is sexual difference in the sounds of A. maculates; (5) to find the relationship between sound characteristics and intrinsic characters of the fish; (6) to define the reproductive season of A. maculates; (7) to find out if there is correlation between the spawning season of A. maculates in Cigu lagoon and presence of the high-frequency sounds in the lagoon. Bimonthly sound recordings were made in Cigu lagoon between February to December 2009. Pulsed, broad-band and high-frequency sounds were present in April, June, and August; number of sounds per minute was higher in August (mean: 52.9 sounds/ min). The sound were characterized by: sound duration: 160.6 ¡Ó 16.6 ms, dominant frequency: 2840 ¡Ó 867.3 Hz, pulse period 12.6 ¡Ó 0.45 ms, pulse duration: 6.0 ¡Ó 0.82 ms, inter-pulse-interval: 6.6 ¡Ó 0.84 ms. The stridulatory sounds of A. maculates are pulsed, broad-band and high-frequency - sound duration: 64.0 ¡Ó 16.74 ms, dominant frequency: 1251 ¡Ó 419.8 Hz, pulse period 7.7 ¡Ó 2.69 ms, pulse duration 5.3 ¡Ó 1.69 ms, inter-pulse-interval 2.4 ¡Ó 1.93 ms. Drumming sounds of A. maculates are harmonic, low frequency - sound duration: 58.5 ¡Ó 25.54 ms, dominant frequency: 442 ¡Ó 96.3 Hz fundamental frequency: 163 ¡Ó 30.98 Hz, pulse period: 6.3 ¡Ó 1.21 ms, pulse duration: 6.3 ¡Ó 1.19 ms. There was significant sexual difference in the stridulatory sound characters including pulse period, inter-pulse-interval, pulse number; females are higher than males in these parameters. There was significant sexual difference in the drumming sound (including dominant frequency) as well; males are higher than females in these parameter. Pulse period of the stridulatory sounds increased significantly with increasing standard body length. Pulse period and pulse duration of the drumming sounds both increased significantly with increasing standard body length, whereas dominant frequency and fundamental frequency both decreased significantly with size. GSI and oocyte diameters were higher in February, April, and June with a peak in April. Reproductive period was considered occurring from April to August (i.e. in spring and summer). This reproductive period coincides with the peak of vocalization. Result of ANOSIM indicates that, H-type sound is significant different from the stridulatory sound of A. maculates - they are in different groups. As the sound source might be at a distance from the recording site, energy in the high frequency range might decay with distance, whereas low frequency range might be cutoff as well. As A. maculates is the only soniferous spices in Cigu lagoon that can emit high-frequency sounds, possibility remains high that the high frequency sound, which resembles the H-type sound, in Cigu lagoon is actually produced by the spotted catfish despite of the difference in frequency-domain features of the sounds.
62

Profiling of Intestinal Microbial Diversity by PCR-DGGE Genes Coding for 16S rDNA and Immunity Status of the Orange Spotted Grouper (Epinephelus coioides) Following Probiotic Bacillus subtilis Administration

Ratih Purwandari, Anggraini 13 December 2012 (has links)
Groupers are an important mariculture fish in Taiwan and Southeast Asian countries. The rapidly growing orange spotted grouper (Epinephelus coioides) has experienced relatively severe bacterial disease problems. The proliferation of pathogens in fish can be suppressed by commensal microbiota. In this context, probiotic seem to offer an attractive alternative. Bacillus subtilisis a probiotic bacteriumthat is administered in diet to suppress proliferation of pathogens. In the present study, E.coioideswere fed for 6 months with diets containing B.subtilis at 0 (control), 0.1 % and 1 %. Percent weight gain and feed efficiency of the 0.1 and 1 % groups were significantlybetter than the control group. The innate cellular response, respiratory burst of the fish fed the 1 % and 0.1 % diet was significantly higher compared to the control group on 10 or 20 days after feeding, and even moresignificanton 30 days.ProbioticBacillus subtilis increased the fish¡¦s intestinal microbial diversity as measured by visible band number and Shannon diversity indexin DGGE analysis. Probiotic Bacillus subtilis also stimulated the population of bacterial species likePaenibacillussp,Lactobacillus oenistrain 59 b, and Methilacidophiluminfernorumstrain V4 that beneficial for Epinephelus coioides. The best dose of probiotic Bacillus subtilis based on growth performances, innate cellular responses and profile of microbiota in fish intestines is 0.1 %, which showed equal efficacy as the 1% diet.
63

The range expansion of the northern barred owl : an evaluation of the impact on spotted owls /

Kelly, Elizabeth G. January 2001 (has links)
Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 41-44). Also available via the World Wide Web.
64

The genetics of resistance to the spotted alfalfa aphid

Powell, William Houston, 1926- January 1962 (has links)
No description available.
65

Studies on the vector ecology of the American dog tick, Dermacentor variabilis, (Say) (Acari: Ixodidae) in Manitoba, Canada

Yunik, Matthew 02 September 2014 (has links)
The American dog tick, Dermacentor variabilis, is an obligate blood feeding ectoparasite. This tick is a known vector of pathogens that affect the health of wildlife, humans, and livestock and is abundant in Manitoba. The etiological agent of bovine anaplasmosis, Anaplasma marginale, along with members of the spotted fever group rickettsiae are bacteria that are transmitted by this tick. I examined the distribution of these bacteria in Manitoba’s tick population using molecular techniques. During the eradication of an outbreak of bovine anaplasmosis in Manitoba, there was no evidence the bacterium had spilled over into the tick population. Rickettsia montanensis was detected with a mean prevalence of infection of 9.8% (range, 0.00 - 21.74% among localities) in 8 of 10 localities within the province. It was also determined that 19.9% (SE ±1.14) of adult questing ticks collected in one vector season overwintered through to the next spring.
66

Evaluation of Puccinia centaureae DC. as a biological control agent of spotted knapweed (Centaurea maculosa Lam.)

Clément, Michel. January 1984 (has links)
No description available.
67

Aspects of the biology of the ladybird beetle Stethorus vagans (Blackburn) (Coleoptera: Coccinellidae) /

Khan, Inamullah. January 2000 (has links)
Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2000. / "A thesis presented in fulfilment of the requirement for the degree of Doctor of Philosophy" Bibliography : leaves 160-183.
68

Clofentezine, fenpyroximate ve amitraz ile seleksiyon yapılmış tetranychus urticae koch populasyonlarının direnç, çoklu direnç, direnç kalıtımının ve bazı enzim düzeylerinin belirlenmesi /

Kara, Fatma Ebru. Ay, Recep. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Bitki Koruma Anabilim Dalı, 2008. / Bibliyografya var.
69

Movement, dispersal, and home ranges of tournament displaced largemouth and spotted bass in Lake Martin, Alabama

Hunter, Ryan Wayne, Maceina, Michael J. January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.57-62).
70

Effects of striped bass stocking on largemouth bass and spotted bass in Lewis Smith Lake, Alabama

Shepherd, Michael David, Maceina, Michael J. January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 64-75).

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