• Title/Summary/Keyword: Natural mating

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Milk yield and kit development of four breeds of rabbit in Ibadan, Nigeria

  • Jimoh, Olatunji Abubakar;Ewuola, Emmanuel Olabisi
    • Journal of Animal Science and Technology
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    • v.59 no.12
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    • pp.25.1-25.7
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    • 2017
  • Background: Rabbit breeding with high performance imported ones would be of benefit for genetic diversity and improvement of performance in domestic rabbit breeds. The rearing of more productive rabbit breeds could be pathway to improve the productivity and reduce the production cost. Maternal nutritional status exert a great influence on reproductive functions of does, which may expand from conception, through gestation and parturition and development of kits to puberty. Methods: Four breeds of rabbit were evaluated for their parturition, weaning and pubertal differences among the rabbit population in Ibadan, Nigeria. The breed consist of Fauve De Bourgogne (FDB), Chinchilla (CHA), British Spot (BS) and New Zealand White (NZW) rabbits. A total of 60 bucks and 360 does consisting of 15 bucks and 90 does per breed were mated in 6 mating cycles, three each of natural mating and artificial insemination. All does were synchronized for estrus with 20 IU pregnant mare serum gonadotropin 48 h prior to mating. The does after parturition were assessed for milk yield (g) and kit survival rate (%) till weaning, weight changes of kits from birth to puberty. At puberty, the pubertal age (days) and weight (g) of the offspring were assessed. Result: Results obtained reveals that British Spot doe had highest milk yield among the breeds which significantly increased growth of kit and weight at weaning in British Spot rabbits. Survival rates of Chinchilla kits were significantly (p < 0.05) higher than Fauve de Bourgogne, British Spot and New Zealand White kits. Puberty attainment of the rabbits indicates that British spot does and Fauve de Bourgogne bucks are early maturing. Conclusion: Chinchilla shows high kit survivability and British spot has highest milk yield among the four breeds of rabbit.

Sensitivity of Phytophthora infestans Isolates to Fungicides Metalaxyl and Ethaboxam in Korea

  • Kim, Byung-Sup;Zhang, Xuan-Zhe;Chung, Eun-Kyoung;Kim, Dal-Soo;Chun, Sam-Jae;Park, Woo-Bong
    • The Plant Pathology Journal
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    • v.19 no.3
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    • pp.143-147
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    • 2003
  • Sensitivity of Phytophthora infestans isolates to fungicides metalaxyl and ethaboxam in Korea was examined with 260 isolates for 3 years (9 isolates in 2000,93 isolates in 2001, and 158 isolates in 2002). Both Al and A2 mating types were found from the isolates collected for 3 years. Al mating type was dominant in the population with 8 isolates (88.9%) in 2000, 84 isolates (89.4%) in 2001, and 138 isolates (87.3%) in 2002. Only some isolates from diseased tomatoes in Buyergun and diseased potatoes in Pyeongchanggun were of the A2 mating type. As for metalaxyl sensitivity, 77.0% of the isolates were moderately resistant with 8 isolates (88.9%) in 2000, 73 isolates (77.7%) in 2001, and 120 isolates (75.9%) in 2002. Meanwhile, those found resistant were 1 isolate (11.1%) in 2000, 16 isolates (17.0%) in 2001, and 33 isolates (20.9%) in 2002. Only 5 isolates (3.2%) were sensitive to metalaxyl in 2002. There was no significant difference in the sensitivity among years. As for ethaboxam, no isolate was able to grow at 5.0 $\mu\textrm{g}$ /ml, and only four isolates (1.5 %) grew at 1.0 $\mu\textrm{g}$ /ml with heavy retardation compared with the untreated control. Based on these 3-year results, the minimum inhibitory concentration (MIC) of ethaboxam to p. infestans was determined to be 0.2-1.0 $\mu\textrm{g}$ /ml. Results indicate that resistance development by p. infestans to ethaboxam is not likely to occur in the natural condition. furthermore, there was no indication of cross resistance between metalaxyl and ethaboxam because all the isolates, regardless of classification for their sensitivity to metalaxyl, were not able to grow at 5.0 $\mu\textrm{g}$ /ml of ethaboxam.

Interspecific Hybridization of the Korean Native Bumblebee Bombus hypocrita sapporoensia and the European Bumblebee B. terrestris

  • Yoon, Hyung-Joo;Park, In-Gyun;Lee, Kyeong-Yong;Kim, Mi-Ae;Jin, Byung-Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • v.23 no.1
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    • pp.167-174
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    • 2011
  • The large bumblebee $Bombus$ $terrestris$, indigenous to Europe and adjacent areas and used extensively for high-value crop pollination, has been artificially introduced to several parts of the world. Here we show the occurrence of interspecific hybridization between the bumblebee species $B.$ $hypocrita$ $sapporoensia$ and $B.$ $terrestris$ under laboratory conditions. The mating and oviposition percentages resulting from the interspecific hybridization of a $B.$ $terrestris$ queen with a $B.$ $h.$ $sapporoensis$ male were higher than those resulting from the intraspecific mating of $B.$ $h.$ $sapporoensis$. Furthermore, a competitive copulation experiment indicated that the mating of $B.$ $h.$ $sapporoensis$ males with $B.$ $terrestris$ queens was 1.2-fold more frequent than the mating of these males with $B.$ $h.$ $sapporoensis$ queens. The interspecific hybridization of a $B.$ $terrestris$ queen with a $B.$ $h.$ $sapporoensis$ male produced either $B.$ $terrestris$ workers or the $B.$ $terrestris$ male phenotype, and the hybridization of a $B.$ $h.$ $sapporoensis$ queen with a $B.$ $terrestris$ male produced $B.$ $h.$ $sapporoensis$ males. Our results indicated that interspecific hybridization occurred between $B.$ $h.$ $sapporoensis$ and $B.$ $terrestris$. These results suggest that such hybridization will have a negative competitive impact and will cause genetic contamination of native bumblebees.

Ovarian Activity of Dromedary (Single Humped) Camel (Camelus dromedarius) in North-Eastern Nigeria

  • Yahaya, M.S.;Takahashi, J.;Matsuoka, S.;Alaku, O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.6
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    • pp.868-870
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    • 1999
  • A total of 69 ovaries were collected from 345 camels slaughtered in Maiduguri abattoir, North-Eastern part of Nigeria, to study the influence of season on ovary weight and corpus luteum count in the dromedary (single humped) camel (Camelus dromedaries). Right ovary was significantly heavier (p<0.01) and had more follicular fluid than the left. Although corpus luteum count increased gradually throughout the study period, no camel had 3 active corpora lutea and only 53 out of the total number had two. Ovarian activity seem to be higher in the cold dry harmattan season, November/December, than during the warmer post rainy season, September/October. These periods can be exploited by farmers, especially peasants who rely heavily on natural mating, to obtain greater conception rates and reduce the chance of failure during mating.

Automated Assembly Modeling using Kinematics Constraints (기구학적 구속조건을 이용한 자동 조립 모델링)

  • Kim Jae Seong;Kim Gwang Su
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2002.05a
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    • pp.272-279
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    • 2002
  • A common task in assembly modeling is the determination of the position and orientation of a set of components by solving the spatial relationships between them. Assembly models could be constructed at various levels of abstraction. They could be classified into component or geometry-level assembly models. The geometry-level assembly design approach using mating constraints such as against and fits is widely used in the commercial modelers, but it may be very tedious in some cases fur designer. In this paper, we propose a new method to construct an assembly model at the component-level by extracting joint mating features from the kinematics constraints specified between components. The assembly model constructed using the proposed method includes hierarchical and relational assembly models, component/sub-assembly positions and degrees of freedom information. The proposed method is more intuitive and natural way of assembly design and it guarantees the topological robustness of assembly modification such as component replacement and modification.

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RAPD Analysis and Cordycepin Concentration of Hybrided Cordyceps militaris Strains by Mating (교잡된 Cordyceps militalis 균주의 RAPD 분석 및 생리활성물질인 cordycepin 함량 측정)

  • Jeong, Jin-Woo;Jin, Cheng-Yun;Kim, Mun-Ock;Lee, Jae-Yun;Choi, Yung-Hyun;Lee, Jae-Dong
    • The Korean Journal of Mycology
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    • v.37 no.1
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    • pp.86-90
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    • 2009
  • The C. militaris belongs to entomopathogenic fungi, which have their specific sequences in internal transcribed spacer regions (ITS1 and ITS2) depending on species. In this study, to identify the phylogenetic relationship of the strain hybrided by mating of C. militaris, we compared DNA sequences of ITS regions and 5.8S ribosomal DNA (rDNA) repeat unit of hybrid strain and its parental strains. The result revealed that hybrid strains are C. militaris species. In addition, cordycepins produced by hybrid strains and other strains of C. militaris were analyzed by HPLC with 20mM $KH_2PO_4$ of mobile phase and C-18 columns. The result indicated that the strain hybrided by mating produce higher concentration of phytochemical cordycepin than other C. militaris strains.

Mating System in Natural Population of Pinus koraiensis at Mt. Seorak Based on Allozyme and cpSSR Markers (동위효소 표지와 cpSSR 표지를 이용한 설악산 잣나무 집단의 교배양식)

  • Hong, Yong-Pyo;Ahn, Ji-Young;Kim, Young-Mi;Hong, Kyung Nak;Yang, Byeong-Hoon
    • Journal of Korean Society of Forest Science
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    • v.102 no.2
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    • pp.264-271
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    • 2013
  • Mating system parameters were estimated in a natural population of Pinus koraiensis which was located at Gwongeumseong in Mt. Seorak, South Korea. The estimated parameters from allozyme were as follows: 0.882 of multilocus outcrossing rates($t_m$), 0.881 of singlelocus outcrossing rates($t_s$), 0.368 of correlated paternity($r_p$), and 2.7 of number of effective pollen contributors. The estimated parameters from cpSSR markers were as follows: 0.831 of average of outcrossing rates and 12.4 of the average number of effective pollen contributors. The average outcrossing rate from two genetic markers was 0.857, which was similar to those estimated in other conifer species. More number of potential pollen contributors was estimated from cpSSR marker analysis compared with that estimated from allozyme marker analysis. This result sugges$t_s$ that cpSSR markers may be more useful than allozyme markers for identifying potential pollen contributors in the analysis of mating system.

Ultrastructural Study of the Liver by Chitosanoligosaccharide Administrated in Rat (키토산올리고당을 섭취한 쥐에서 간 미세구조의 연구)

  • Kim, Young-Ho;Roh, Young -Bok
    • Applied Microscopy
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    • v.31 no.4
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    • pp.385-392
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    • 2001
  • The purpose of this study was to evaluate the histological toxicity of chitosanoligosaccharide on the rat. A healthy male of Wistar rat that weighted $250{\pm}350g$ was used for experiment The experimental group was divided into five groups. Group 1 was control group which treated with general food Group 2 was $F_1$ generation which was born by mating of 0.1% (1 mg/ml) chitosanoligosaccharide was supplied by feeding ad libitum for 30 days. Group 3 was $F_2$ generation which was born by mating $F_1$ generation. Group 4 was treated with 90 days of 0.1% (1 mg/ml) chitosan oligosaccharide. Group 5 was treated with 365 days of 0.1% (1 mg/ml) chitosanoligo saccharide. All experimental groups were used to 10 rat. The results were as follow: The RER dilation was observed Group 4. However, there were no significantly changes of ultrastructures in the other groups compared to the control. It was concluded that chitosanoligosaccharide can be used for nontoxic natural material.

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Bioacoustic Change of Dybowski's Brown Frog by Highway Noise (고속도로 소음에 의한 북방산개구리의 생물음향학적 특성 변화 연구)

  • Ki, Kyong-Seok;Sung, Chan-Yong
    • Korean Journal of Environment and Ecology
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    • v.28 no.3
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    • pp.273-280
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    • 2014
  • This study examined whether Dybowski's brown frogs(Rana dybowskii) in noisy highway roadsides had different mating calls from those in natural sites. We selected four study sites: two rice paddy sites in Youngdong Highway roadside and two nearby natural counterparts. Frog calls were recorded between 18:30 and 20:00 on February 24, February 27, and March 14, 2014. Frog calls in the natural sites had fundamental frequency approximately at 700 Hz with two to four apparent harmonics, while frog calls in the highway sites had higher fundamental frequency with up to seven apparent harmonics. Analysis of variance (ANOVA) shows that a roadside site that are directly exposed to highway noise had statistically higher frog calling frequency than other study sites. However, the higher calling frequency was not found in another roadside site that differed in elevation from the highway and was buffered by forests. These results indicate that male frogs in a noisy highway roadside called females with a higher pitch and more apparent harmonics to avoid being masked by highway noise. These results also suggest that there is a threshold noise level that interrupts frog's mating behavior and it is needed to maintain highway roadside noise to this threshold level.

Studies on Biological Diversity of Firefly in Japan

  • Suzuki, Hirobumi
    • International Journal of Industrial Entomology and Biomaterials
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    • v.2 no.2
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    • pp.91-105
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    • 2001
  • Taxonomic and phylogenetic studies of firefly in Japan have been reviewed. Fourty-six lampyrid species and one rhagophthalmid are distributed in the Japanese Islands including the Ryukyus. Recently, molecular phylogenetic approaches have been employed in the systematic study of firefly using mitochondrial and luciferase genes. Based on the molecular phylogenetic trees, evolutionary process of flashing patterns related strictly to mating behavior was estimated. Furthermore, genetic diversity studies revealed geographic differentiation patterns within species, and conservation measures of firefly were proposed to protect genetic resources endemic to the localities.

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