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91.
Agna Rita dos Santos Rodrigues Aline Freitas Spíndola José Eudes de Morais Oliveira Jorge Braz Torres 《Phytoparasitica》2013,41(3):285-294
Considered a generalist species among the coccinellids, the multicolored Asian lady beetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) feeds upon small arthropods and non-prey plant products, a practice which might enhance its ability to colonize various ecosystems but carries the potential to expose it to prey quality variation and insecticide use. Thus, we examined the effect of four different diets on the development, reproduction, and response to the insecticide lambda-cyhalothrin in this species. Three groups of larvae received laboratory-reared diets: (i) eggs of Anagasta kuehniella (Zeller) (Ak); (ii) eggs of Sitotroga cerealella (Olivier) (Sc); and (iii) eggs of A. kuehniella + S. cerealella at the proportion 1:1; and one group received wild-caught cotton aphids, Aphis gossypii Glover (Ag). Notwithstanding the generalist feeding behavior of H. axyridis, development and reproduction results were superior with diets of Ag or Ak compared with the diet combining 1:1 Ak + Sc or the diet of Sc eggs only. Furthermore, the Sc diet did not result in satisfactory development and reproduction. Despite this significant variation in biological responses, insecticide susceptibility studies using adults that had been reared on these diets showed no statistically significant differences in susceptibility to the lambda-cyhalothrin. 相似文献
92.
93.
BC Hosking TM Griffiths RG Woodgate RB Besier AS Le Feuvre P Nilon C Trengove KJ Vanhoff BG Kaye-Smith W Seewald 《Australian veterinary journal》2009,87(11):455-462
Objective To determine the efficacy of monepantel, a developmental compound from the amino-acetonitrile derivative class of anthelmintics, against field infections of gastrointestinal nematodes in sheep.
Procedures Comparisons of efficacy (using standard faecal worm egg count reduction tests) and safety (on the basis of visual observations) were made in a large-scale field study in Australia, between groups of sheep treated with either an oral solution of monepantel or a registered anthelmintic. The sheep were naturally infected with the major gastrointestinal nematode genera present in Australia.
Results The post-treatment efficacy results for monepantel were: at 7 days (±1 day) efficacy was >98%; at 14 days (±1 day) it was generally close to or >99%; and at 21 days (±1 day) efficacy was consistently >99%. A high proportion of the targeted nematode populations were confirmed as being resistant to one or more of the currently available anthelmintic classes.
Conclusions Monepantel when used under field conditions at a minimum dose rate of 2.5 mg/kg was highly effective against mixed-genus natural field infections of the major gastrointestinal nematode genera including Haemonchus , Teladorsagia ( Ostertagia ), Trichostrongylus , Nematodirus , Chabertia and Oesophagostomum . This result included efficacy against some populations resistant to the currently available broad-spectrum anthelmintics. Few Cooperia spp. were present to allow confirmation of efficacy against this genus. On no occasion after treatment did any commercial anthelmintic-treated groups have significantly lower faecal egg counts than the monepantel-treated groups. Monepantel was safe for the target animals and human operators when used in a field situation. 相似文献
Procedures Comparisons of efficacy (using standard faecal worm egg count reduction tests) and safety (on the basis of visual observations) were made in a large-scale field study in Australia, between groups of sheep treated with either an oral solution of monepantel or a registered anthelmintic. The sheep were naturally infected with the major gastrointestinal nematode genera present in Australia.
Results The post-treatment efficacy results for monepantel were: at 7 days (±1 day) efficacy was >98%; at 14 days (±1 day) it was generally close to or >99%; and at 21 days (±1 day) efficacy was consistently >99%. A high proportion of the targeted nematode populations were confirmed as being resistant to one or more of the currently available anthelmintic classes.
Conclusions Monepantel when used under field conditions at a minimum dose rate of 2.5 mg/kg was highly effective against mixed-genus natural field infections of the major gastrointestinal nematode genera including Haemonchus , Teladorsagia ( Ostertagia ), Trichostrongylus , Nematodirus , Chabertia and Oesophagostomum . This result included efficacy against some populations resistant to the currently available broad-spectrum anthelmintics. Few Cooperia spp. were present to allow confirmation of efficacy against this genus. On no occasion after treatment did any commercial anthelmintic-treated groups have significantly lower faecal egg counts than the monepantel-treated groups. Monepantel was safe for the target animals and human operators when used in a field situation. 相似文献
94.
Luciana Lasry Benchimol Tatiana de Campos Sérgio Augusto Morais Carbonell Carlos Augusto Colombo Alisson Fernando Chioratto Eduardo Fernandes Formighieri Lígia Regina Lima Gouvêa Anete Pereira de Souza 《Genetic Resources and Crop Evolution》2007,54(8):1747-1762
A common bean genomic library was constructed using the ‘IAC-UNA’ variety enriched for (CT) and (GT) for microsatellite motifs. From 1,209 sequenced clones, 714 showed microsatellites distributed over 471 simple and 243 compound motifs. GA/CT and GT/CA were the most frequent motifs found among these sequences. A total of 123 microsatellites has been characterized. Out of these, 87 were polymorphic (73.7%), 33 monomorphic (26.8%), and 3 (2.4%) did not amplify at all. In a sample of 20 common bean materials selected from the Agronomic Institute Germplasm Bank, the number of alleles per locus varied 2–9, with an average of 2.82. The polymorphic information content (PIC) of each marker varied from 0.05 to 0.83, with a 0.45 average value. Cluster and principal coordinate analysis of the microsatellite data were consistent with the original assignment of the germplasm accessions into the Andean and Mesoamerican gene pools of common bean. Low polymorphism levels detected could be associated with the domestication process. These microsatellites could be a valuable resource for the bean community because of their use as new markers for genetic studies. 相似文献
95.
Fabiana Aparecida Santilli Brandão Kele Amaral Alves Danielle Cristina Calado de Brito Leda Maria Costa Pereira Glayciane Bezerra de Morais Lucy Vanessa Sulca Ñaupas Samara Silva de Souza Benner Geraldo Alves Ana Paula Ribeiro Rodrigues Dárcio Ítalo Alves Teixeira 《Reproduction in domestic animals》2021,56(8):1156-1161
The present study evaluated the effect of Ovarian Tissue Cryosystem (OTC) on follicular morphology and density, as well as on stromal cell density of vitrified canine ovarian tissue. Canine ovarian fragments collected from adult female dogs in stages of the random oestrous cycle were fixed (FC, fresh control) or vitrified (VIT) with an OTC device. After vitrification and warming, the fragments were fixed for histological analysis. Overall, the mean percentage of normal pre-antral follicles decreased after vitrification procedure (FC: 74.5% ± 1.6% vs. VIT: 52.05% ± 1.5%). Although the rates of normal primordial (71.1% ± 1.8%) and secondary (0.7% ± 0.4%) follicles vitrified showed a reduction (p < .05), vitrification using OTC showed considerable preservation of follicles, when compared to the fresh control (81.1% ± 1.5% and 2.3% ± 0.6%, respectively). The mean follicular density was maintained after vitrification (FC: 199.65 ± 12.8 vs. VIT: 199.68 ± 10.8), whereas the stromal cell density decreased in the VIT group. Based on the results, we recommend the use of OTC for vitrification of canine ovarian tissue. 相似文献
96.
AS Santos Filho MAL Oliveira JGL Caldas PF Lima & IV Donato 《Reproduction in domestic animals》2001,36(3-4):207-210
The objective of this study was to examine the follicular dynamics of five-eighths Girolando cows by observing the number of follicular development waves, days of emergence of those waves, diameters of the dominant and largest subordinate follicles and the processes of follicular selection and dominance. Ovarian follicle dynamics were monitored for 24 oestrous cycles in 12 cows, of 4 to 10 years of age, presenting regular oestrous cycles and with body scores between 3 and 4. Ovaries were observed daily for two consecutive oestrous cycles and follicles were measured with ultrasonographic equipment. The dominant follicle was considered to be that which presented a diameter ≥ 10 mm for three consecutive days and on the day of wave emergence, when a group of follicles measuring 3–5 mm in diameter would appear. Of the 24 cycles monitored, 62.5% presented two waves of follicular development and 37.5% presented three waves. The cycles presenting two waves had an average duration of 20 days, with the emergence of the waves on days 1 and 9, whereas the cycles presenting three waves had an average duration of 22 days, with emergences on days 1, 10 and 16. For cycles with two waves, both the first and second dominant follicles reached an average size of 13.8 mm, with the first regressing on day 10 and the second ovulating around day 20. For cycles with three waves, the dominant follicles of the first and second waves reached maximum diameters of 11.8 and 12 mm, respectively, with the first regressing on day 11 and the second regressing on day 17. The third dominant follicle reached a maximum diameter of 12.4 mm on day 20, and ovulated on day 22. These results lead to the conclusion that the follicular dynamics of five-eighths Girolando cows are characterized by the presence of two to three waves of follicular growth. 相似文献
97.
98.
Vedovatto Marcelo da Silva Pereira Camila Cortada Neto Ibrahim Miranda Moriel Philipe Morais Maria da Graça Franco Gumercindo Loriano 《Tropical animal health and production》2020,52(2):881-886
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of injectable trace minerals (ITM) at the time of weaning on growth, antioxidant, and immune response... 相似文献
99.
Gama Kallidiane Vaneska Mendes Fernandes Pereira Filho José Morais Soares Rafael Farias Cordão Maiza Araújo Cézar Marcílio Fontes Batista Ana Sancha Malveira de Azevedo Silva Aderbal Marcos Madruga Marta Suely Oliveira Ronaldo Lopes Bezerra Leilson Rocha 《Tropical animal health and production》2020,52(2):601-610
Tropical Animal Health and Production - To compare the fatty acid (FA) composition, and chemical and tissue composition of meat, 24 uncastrated males, 12 sheep of the Santa Inês breed, and 12... 相似文献
100.
Sandra HERVÍAS‐PAREJO Manuel NOGALES Beatriz GUZMN María del Mar TRIGO Jens M. OLESEN Pablo VARGAS Ruben HELENO Anna TRAVESET 《Integrative zoology》2020,15(2):144-148
Lizards have been reported as important pollinators on several oceanic islands. Here we evaluate the potential role of Galápagos lava lizards (Microlophus spp.) as pollinators across their radiation. Over 3 years, we sampled pollen transport by 9 lava lizard species on the 10 islands where they are present, including 7 single‐island endemics. Overall, only 25 of 296 individuals sampled (8.4%) transported pollen of 10 plant species, the most common being Prosopis juliflora, Exodeconus miersii, Sesuvium sp. and Cordia leucophlyctis. At least 8 of these plant species were native, and none were confirmed as introduced to the archipelago. Despite the low overall proportion of individuals carrying pollen, this was observed in 7 of the nine lizard species, and on 8 of the ten main islands (Española, Fernandina, Floreana, Isabela, Marchena, Pinta, Santa Cruz and Santiago), suggesting that this is a widespread interaction. The results reported here support the potential role of lava lizards as pollinators across their radiation, although they may represent a relatively modest contribution when compared with birds and insects. However, we cannot discard that lizards may be ecologically significant for particular plant species and ecosystems given the specific climatic condition and functional diversity of each island. 相似文献