Thesis (M.Ag.Sci. 1977) from the department of Agronomy, University of Adelaide. / Article in end pocket.

Thesis (Ph. D.)--Ohio state University, 1929. / Cover title. Autobiography. Published also as Ohio. Agricultural experiment station. Bulletin 436. Bibliography: p. 38-42.

Thesis (Ph. D.)--Ohio state University, 1929. / Cover title. Autobiography. Published also as Ohio. Agricultural experiment station. Bulletin 436. Bibliography: p. 38-42.

Two experiments were conducted to study the effects of dietary protein quality on the growth of juvenile cobia Rachycentron canadum. Experiment I was to find out the maximum level of steam dried blood meal and spray dried blood meal can be used in the diet for juvenile cobia. Experiment II examined how juvenile cobia utilizes supplemental amino acids. In Experiment I, 9 test diets were evaluated. In the first group, steam dried blood meal was used to partially replace fish meal. The replacement levels were 0, 10, 20, 30 and 40% of the fish meal protein. In the second group, crystalline methionine, which was 0.1 and 0.2% of the diets, was added respectively to 2 diets in which 20 and 40% of the fish meal protein was replaced by blood meal. In the third group, spray dried blood meal was used to replace fish meal protein at 20 and 40% instead of steam dried blood meal. Juvenile cobia with an initial weight of 72g were fed with the test diets for 8 weeks. The results showed that the percent weight gain (PWG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER) and net protein utilization ratio (NPU) were significantly reduced (P¡Õ0.05) when the replacement level was increased from 20% to 30%. Spray dried blood meal was more effectively than steam dried blood meal was at high replacement level (40%) than low replacement level (20%). Supplementation of crystalline methionine in the cobia diet had no positive effects. In Experiment II, 8 test diets were studied. The control diet contained only fish meal as the sole protein source. The other seven diets all contained steam dried blood meal which replaced 30% of fish meal protein. In the first group of 3 diets, (1) crystalline methionine, (2) crystalline methionine and crystalline isoleucine, (3) crystalline methionine, crystalline isoleucine and crystalline arginine were added, respectively. Two diets were supplemented with (1) microencapsulated (glycerol monostearate) methionine, (2) microencapsulated methionine and microencapsulated isoleucine. Two diets were supplemented with (1) microcoated (cellulose acetate phthalate) methionine, (2) microcoated methionine and microcoated isoleucine. Juvenile cobia with an initial weight of 33g were fed with the test diets for 8 weeks. The results showed that when the fish meal was partially replaced and amino acids were added, the PWG, SGR, FCR, PER and NPU of the cobia were significantly reduced compared to the control group (P¡Õ0.05). In conclusion, steam dried blood meal could effectively replace fish meal up to 20% of the fish meal protein, which was 6.2% of the diet. Spray dried blood meal showed better effects on the growth of fish than steam dried blood meal when given at high level. The two types of blood meal were no difference when the replacement levels were low. Juvenile cobia were not able to effectively use the different types of amino acids evaluated in the experiments.

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 86-93). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 86-93). Also available on the Internet.

Master of Science / Department of Entomology / Marcelo Ramalho-Ortigao / Sand flies (Diptera:Psychodidae) are vectors of parasites of the genus Leishmania transmitted to suitable vertebrate host during blood feeding. For blood feeding arthropods, including sand flies, blood meal digestion requires the secretion of inhibitory molecules, such as Kazal-type serine proteinase inhibitors that are involved in preventing the blood from coagulating within the mouthparts and the midgut. Previous studies have identified such molecules in mosquitoes, ticks, and triatomine bugs. Following studies of the midgut transcriptome of Phlebotomus papatasi, the principal vector of Leishmania major, two non-classical Kazal-type serine proteinase inhibitors were identified (PpKzl1 and PpKzl2). We are interested in the role of these proteins as inhibitors of coagulation cascades, in addition to their potential effects on blood digestion in P. papatasi. Ppkzl1 is similar to thrombin and trypsin inhibitors in triatomines and mosquitoes and Ppkzl2 is similar to Kazal-type inhibitors in mosquitoes with unknown function. Analyses of expression profiles indicated that although both transcripts are expressed prior to blood feeding in the midgut of P. papatasi they are tightly regulated by the blood meal. Reverse genetics studies using RNAi-targeted knockdown of PpKzl1 and PpKzl2 by dsRNA injection did not result in a detectable effect on mRNA expression levels. Thus, we expressed a recombinant PpKzl2 in a mammalian expression system (CHO-S free style cells) that was applied to in vitro studies to assess activity against various serine proteinases. Recombinant PpKzl2 inhibited chymotrypsin at nanomolar levels and also inhibited thrombin and trypsin at micromolar levels, suggesting that native PpKzl2 is an active serine proteinase inhibitor and may regulate digestive enzymes and thrombin in the midgut. Leishmania development within the sand fly midgut is faced with several barriers that can severely impact the parasites. For transmission to occur, parasites must be able to overcome these barriers including digestive proteinases, escape from the peritrophic matrix, and midgut attachment. Early stages of Leishmania are susceptible to killing by digestive proteinases in the sand fly midgut. Thus, targeting serine proteinase inhibitors may provide a new strategy to prevent transmission of Leishmania.

The Asian tiger mosquito, Aedes albopictus (Skuse), is a worldwide nuisance pest that is capable of vectoring several viruses of public health concern. This invasive mosquito has recently expanded its habitable range through its utilization of artificial breeding sites, often due to the activity of humans. These factors, combined with additional expansion due to global changes in climate, have led to invigorated efforts to mitigate the impact of Ae. albopictus. Because it is a diurnal species, standard mosquito control efforts utilizing spray trucks or planes to administer insecticides offer little control, as these methods are directed towards crepuscular species. Barrier spray applications, however, have been shown to achieve a significant reduction in local mosquito pressure while requiring less insecticide application. The design behind barrier sprays is to apply insecticide treatments only around areas of interest, instead of trying to eradicate the local population of mosquitoes. These studies were conducted to evaluate the efficacy of different pyrethroid barrier treatments against Ae. albopictus mosquitoes, and to examine the impact of the most effective treatment on local mosquito populations when applied to suburban residences. Three pyrethroids were examined in these studies: Demand® CS (lambda-cyhalothrin), Talstar® Professional (bifenthrin), and Suspend® Polyzone® (deltamethrin). The following factors affecting pyrethroid barrier treatments showed significant impacts on the knockdown and mortality rates of Ae. albopictus mosquitoes: the plant species, the label rate at which treatments were applied, the active ingredient used in the treatment applications, the time of exposure to the treated foliage, the presence/absence of a blood meal in the mosquito, and the time after treatment. Demand CS treatments showed the highest proportions of knockdown and mortality in adult female Ae. albopictus mosquitoes and did so for the longest amount of time, regardless of the length of the exposure time. Because the Demand CS formulation of lambda-cyhalothrin was shown to be the most effective treatment in the previous studies, it was applied as a barrier treatment to suburban residences in Roanoke, Virginia, in a field trial. Applications of Demand CS as a barrier spray were shown to significantly reduce mosquito catch numbers inside the treated barrier throughout the 8 week study, as compared to the control properties. The findings of these studies indicate that many factors, pertaining to both the insecticides used and to the environment in which they are applied, play a role in influencing the efficacy of a pyrethroid barrier treatment for the control of Aedes mosquitoes. Thus, it is important to gather relevant information before the application of a barrier spray treatment to design the most appropriate program for the situation. / Doctor of Philosophy / Mosquitoes in Virginia are capable of transmitting many different diseases to humans and livestock. Many different treatment options are available to protect humans from these populations of mosquitoes. Some of these options can be performed for a whole community, such as area-wide fogging or treatments from truck-mounted sprayers, while others are applied to properties individually, like mosquito misting systems or barrier sprays. Applying long-lasting insecticides to the edge of an area can help to protect the inside of the area from mosquitoes, and this is called barrier spraying. Barrier sprays, in particular, have become a popular choice for homeowners, and they are successful at limiting human exposure to local mosquito populations. The experiments conducted here looked at three different insecticides used in these treatments and compared them for their ability to inhibit and kill Asian tiger mosquito. Other factors that potentially influenced effectiveness were examined, such as the plant type, the length of time since the treatment was applied, and whether or not the mosquito had taken a blood meal. These experiments examined three commonly used pyrethroid insecticides to determine their efficacy against the local Asian tiger mosquito. Suspend Polyzone lasted a long time but did not produce sufficient mortality, Talstar Professional killed large numbers of mosquitoes, but for a short period, and Demand CS lasted a long time and showed a high mortality rate. These studies showed that the three different insecticides lasted on the plants for different amounts of time, but also that the insecticides needed different amounts of contact time to kill mosquitoes. This information is essential because understanding how a treatment loses effectiveness over time can help with deciding when retreatment is needed. It was also found that the different insecticides were affected by the plants that they were sprayed onto, meaning that certain insecticides did better when sprayed on specific plants. Results from these studies revealed that Asian tiger mosquitoes that had just fed on human blood were more likely to die from insecticide treatments. Thus, even if a mosquito should bite an infected person, barrier spray treatments of their property will lower the chances that the mosquito can spread the disease to other people.

Thirty six Holstein cows in their first, second, third or fourth lactation were used in 2 x 2 factorial design to evaluate nitrogen (N) and carbon (C) partitioning to milk, urine, feces, and body tissue during early and midlactation. Diets containing 16% CP were formulated with 30 or 39% rumen undegradable protein (RUP) obtained by substituting blood meal (EM) for soybean meal (SBM). Each level ofRUP was formulated with supplemental phosphorus from mono- and dicalcium phosphate or wheat bran. Dry matter intake was higher in midlactation compared with early lactation, and increased as parity increased. Addition of BM to the diets decreased milk protein percentage and yield compared with SBM. Fecal N excretion was higher for cows fed BM due to lower N digestibility (67 versus 63%). Cows fed SBM retained more N and partitioned more N into milk than cows fed BM. Cows partitioned approximately 49, 40, and 11% of absorbed N to urine, milk, and tissue, respectively. Concentration of plasma urea N was correlated with milk urea N (r = .50). Overall, data indicated that cows fed 16% dietary CP with SBM or BM met their requirements for milk and tissue protein synthesis. Carbon partitioning was very similar to N partitioning in response to parity. Using a fermentation balance equation, it was estimated that .3 and 3.1 kg C were partitioned daily to methane and carbon dioxide, respectively. Estimated data indicated that 36% of intake C and 57% of absorbed C were lost to the atmosphere as carbon dioxide plus methane. / Master of Science

Les zones pastorales méditerranéennes sont favorables à la diversité et à l’abondance des Tabanidae. Or, la réémergence de certaines maladies animales en Europe (e.g. besnoitiose bovine) a mis en avant leur rôle de vecteur mécanique. Cependant, la richesse biologique et la vulnérabilité des milieux pastoraux impliquent de réduire l’usage des insecticides contre les ectoparasites. Nous avons donc cherché à mieux connaître l’activité des taons dans les estives et àréfléchir à des méthodes de contrôle pratiques, efficaces et sélectives. Les pièges attractifs ou les répulsifs utilisables dans une stratégie « push-pull » impliquant de bien connaître l’olfaction des espèces cibles, nous nous sommes intéressés à la physiologie olfactive des taons et aux composés chimiques qui modulent les interactions avec leurs hôtes.Les travaux sur l’écologie des taons dans les Pyrénées ont montré que l’exposition, l’altitude et la structure paysagère influençaient leur distribution spatio-temporelle, et que les conditions climatiques influençaient l’activité de piqûre des femelles. De plus, le caractère trophique opportuniste des femelles a été confirmé et le cerf est apparu comme un hôte de choix. Les réponses physiologiques et comportementales de Tabanus bromius et d’Atylotus quadrifarius aux odeurs d’urines et de leurs constituants ont révélé des différences de sensibilité olfactive entre ces deux espèces, la forte attractivité de l’urine de cheval s’expliquant probablement par la présence de composés volatiles qui agiraient en synergie. Pour conclure, nous proposons pour les troupeaux en estives des mesures de protection contre les taons et des perspectives de recherche pour ce groupe. / Mediterranean pastoral areas are favourable to the diversity and abundance of Tabanidae. On the other hand, their role as mechanical vectors was highlighted by the re-emergence of animal diseases in Europe (e.g. Bovine Besnoitiosis). However, the biological richness and vulnerability of pastoral communities involve reducing the use of insecticides against ectoparasites. The objectives of this thesis were to better understand the activity of horse flies in summer pastures and to consider practical, efficient and selective pest control methods. A “push-pull” strategy using attractive traps and/or repellents implies a good knowledge of insect olfaction. Therefore, it was interesting to study the olfactory sensitivity of horse flies and semiochemicals that affect vector-host interactions. In the Pyrenean mountains, work on the ecology of horseflies showed that their spatiotemporal distribution was influenced by exposure, altitude and landscape structure, and that the biting activity of females was related to climatic conditions. Moreover, the opportunistic feeding pattern of tabanids was confirmed with a preference for red deer. The physiological and behavioural responses of Tabanus bromius and Atylotus quadrifarius to urines volatiles and their constituents revealed differences between the olfactory sensitivity of these two species. The high attractiveness of aged horse urine is likely to be due to the mixture of various active compoundsthat may act synergistically. To conclude, pest control methods to protect cattle against horse flies in summer pastures and new research opportunities are discussed.