Agricultural Science Commons^™

Transmission Of Sarcocystis Suihominis From Humans To Swine To Nonhuman Primates (Pan Troglodytes, Macaca Mulatta, Macaca Irus), R. Fayer, A. O. Heydorn, A. J. Johnson, R. G. Leek

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Sporocysts of Sarcocystis suihominis obtained from human feces were used to infect swine. Heart, tongue, and skeletal muscle from experimentally infected and noninfected control swine were fed via stomach tube to nonhuman primates including chimpanzees (Pan troglodytes), rhesus monkeys (Macaca mulatta), and cynomolgus monkeys (Macaca irus). All primates fed infected swine tissues shed sporocysts beginning 13 to 15 days postinfection and were still shedding sporocysts at the conclusion of the experiment, 30 days postinfection. Rhesus and cynomolgus monkeys were fed infected swine tissues a second time and shed sporocysts. All primates remained in good …

Grain Crop Variety Trials Western Australia 1978-1979, H. M. Fisher, G. B. Crosbie

Grain and other field crops research reports

The regional crop variety testing programme conducted by the Western Australian Department of Agriculture covers the final two stages of a four stage process of evaluating locally produced crossbreds and introduced material comprising:-

Plant Breeder Trials

Stage 1: Initial small plot yield tests on early generation material - 1 to 3 sites. Stage 2: Small plot yield tests on selected material (F5 derived) - 3 to 4 sites.

Regional Testing Programme

Stage 3: Large scale preliminary trials - 9 to 10 sites. Stage 4: Large scale final yield trials - 40 to 50 sites.

The basis of the regional programme …

Fertilizing Capacity And Ultrastructure Of Fowl And Turkey Spermatozoa Before And After Freezing, M. R. Bakst, T. J. Sexton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The fertilizing capacity, motility and ultrastructure of fowl and turkey spermatozoa were examined at various stages of the freezing process. For both species, fertility and motility were depressed after equilibration with dimethylsulphoxide at 5 °C. After freezing, motility was maintained at 55% for fowl spermatozoa and 40% for turkey spermatozoa; however, fertility was 55% for the fowl and 0% for the turkey. Qualitatively, the damage to the spermatozoa of both species was nearly identical, as revealed by scanning and transmission electron microscopy. The plasmalemma was the primary site of damage. 'Bent' spermatozoa, coiled tails and swollen mitochondria were also present. …

Uterine Blood Flow Of Cows During The Oestrous Cycle And Early Pregnancy: Effect Of The Conceptus On The Uterine Blood Supply, S. P. Ford, J. R. Chenault, S. E. Echternkamp

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Blood flow to each uterine horn of cows during the oestrous cycle and early pregnancy was determined daily by use of electromagnetic blood flow probes placed around both middle uterine arteries. The pattern of blood flow to uteri of pregnant and non-pregnant cows was similar until Day 14 after mating or oestrus. Between Days 14 and 18 of pregnancy blood flow to the uterine horn containing the conceptus increased (P < 0.01) 2- to 3-fold, whereas blood flow to the non-gravid uterine horn in these cows remained constant. No corresponding increase in blood flow to the uterine horn ipsilateral to the ovary bearing the CL was observed in non-pregnant cows during this 4-day period. By Day 19 of pregnancy, blood flow to the gravid uterine horn had returned to a level similar to that observed on Day 13. Blood flow to both uterine horns of pregnant cows remained constant from Days 19 to 25 and then increased to the gravid horn (P < 0.01) markedly until Day 30 whereas blood flow to the non-gravid horn remained low. Uterine blood flow during the oestrous cycle of non-pregnant cows was positively correlated (P < 0.01) with systemic concentrations of oestradiol and the ratio of oestradiol (pg/ml) to progesterone (ng/ml). There was no association between oestradiol concentrations and blood flow to the gravid uterine horn. These data indicate local control of uterine blood flow by the bovine conceptus which may function to create optimal conditions for the continuation of pregnancy.

Increased Lamb Production With Rams Exposed To Short Daylengths During The Nonbreeding Season, B. D. Schanbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Exposure of rams during the nonbreeding season (anestrous period) to short daylengths will initiate a new sexual cycle characterized by testicular growth, increased mating activity and improved semen quality. Lambing results accumulated from 300 potential matings indicate that rams exposed to artificial photoperiods of 8 hr light and 16 hr darkness for 10 weeks (referred to as rams on short-days) are more fertile than control rams maintained under the relatively long days of spring. When five control rams were penned individually with 30 ewes synchronized with progestogen and PMSG, 67% of the ewes were mated. Eighty-nine percent of the ewes …

Growth Analysis Of Tall Fescue Genotypes Differing In Yield And Leaf Photosynthesis, Wallace Wilhelm, C. J. Nelson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Relationships between leaf photosynthesis and yield have not been well defined in forage grasses. Therefore, leaf growth, dry matter distribution, carbohydrate concentration, and growth analysis of four genotypes of tall fescue (Festuca mundinacea Schreb.) were examined. Genotypes, selected in the field for high and low CO₂ exchange rate (CER) in combination with high and low yield, were compared in an attempt to study the relationship between photosynthesis and yield.

In the vegetative growth stage, high yielding genotypes produced greater amounts of all plant parts (leaves, stem bases, and roots) than did low yielding genotypes; however, low yielding genotypes …

Leaf Growth, Leaf Aging, And Photosynthetic Rate Of Tall Fescue Genotypes, Wallace Wilhelm, C. J. Nelson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Leaf growth and leaf aging both influence the total amount of CO, fixed by a particular leaf in the canopy during its photosynthetically productive life. Four genotypes of tall fescue (Festuca arundinacea Schreb.) were selected for all combinations of high and low COB exchange rates (CER) and yield. The purpose of this study was to determine CER during aging and leaf growth rates of tall fescue genotypes in growth chambers and in the field on a Mexico silt loam (Udollic Ochraqualfs; fine, montmarillonitic, mesic). Leaf growth of vegetative tillers in controlled environments was continuous throughout the day for all …

Effects Of Row Width And Seeding Rate On Yield And Other Agronomic Characteristics Of Three Soybean Cultivars, Russell Kithcart

Masters Theses & Specialist Projects

Soybeans have traditionally been grown in rows wide enough to allow mechanical cultivation and to increase lodging resistance. Improved cultivars and herbicides have permitted farmers to obtain yield advantages from narrower rows. The growth response of soybeans to variations in row width and seeding rates depends upon the cultivar and geographic location.

“Williams,” “Mitchell,” and “Essex” cultivars were planted at row widths of 18, 36, 54, and 72cm. at seeding rates of 33, 67, 100 and 134 kg/ha in multi-row plots. Data were collected from each plot for seed yield, lodging, plant height, height of lowest pod, seed and population …

Irradiance Response Of Tall Fescue Genotypes With Contrasting Levels Of Photosynthesis And Yield, Wallace Wilhelm, C. J. Nelson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The purpose of this study was to determine if genotype by irradiance interactions or genetic variation in diurnal trends of CO, exchange rate (CER) influenced the CER-yield relationship in tall fescue (Festuca mundinucea Schreb.). Genotypes were selected in the field for high CER-high yield, high CER-low yield, low CER-high yield, and low CER-low yield. Responses of CER to photosynthetic photon flux density (PPFD) of these genotypes were determined using both growth chamber- and field-grown material. The shapes of the PPFD response curves were similar for all genotypes, and saturation occurred at approximately 1,200 μE m^-2 sec^-1 (400 …

Bulletin No 3573 - Wheat Diseases In Western Australia, A. G. P. Brown, G. C. Mac Nish

Bulletins - 3000 - 3999

Diseases caused by pathogenic organisms can seriously affect the yield of wheat. Some diseases are comparatively rare whereas others occur over a large area of the wheatbelt year after year.

it is important to be able to identify diseases correctly so that the appropriate control measures can be applied, In the following article the diseases of wheat caused by pathogenic organisms are illustrated, with their symptoms described, and where possible, the control measures given.

Proceedings Of The 5th Annual Meeting, Southern Soybean Disease Workers (March 21-23, 1978, Fort Walton Beach, Florida): 3 P'S In A Pod - Policies, Protection, Production

Southern Soybean Disease Workers: Conference Proceedings

Contents

Farm Policies, Weldon Barton (Assistant US Secretary of Agriculture)

World Soybean Problems, Glen Whitney, Dick Ford, and Frank Ray

Interrelation of Governmental Agencies with Industry, University, and Soybean Producers
EPA: Relationship and Responsibility to Agriculture and the Public, Nathan Chandler
EPA: Problems and Requirements of Registration, Herb Harrison
State: Pesticide Impact Program, Charles Smith
Industry: View on Benefit and Risk of the Pesticide Business, Charles Gilbert
University: Role of Land Grant University in Pesticide Development, James Martin
Producer: What's Needed, "Profit or Perish," Peter Myers

DBCP Status Report and Other Nematicides
Shell Chemical, Max Sckerl
Dow Chemical, Walter Miller …

Bulletin 4048: Salt Land And What To Do About It, C V. Malcolm

Bulletins 4000 -

Since the development of land for agriculture in Western Australia more than 1 600 square kilometres of land has become too saline for normal crops and pasture, and the area is increasing. Much of this land was previously the most fertile crop land and on some farms salinity constitutes a major problem.

The purpose of this booklet is to impart an understanding of the nature and cause of saltland in Western Australia. The methods of treatment are explained in the light of this understanding. The material in the booklet is based on a detailed review 'Soil salinity in South Western …

Testicular Steroid Secretion In Response To Gnrh-Mediated Lh And Fsh Release In Bulls, B. D. Schanbacher, S. E. Echternkamp

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Assay of frequently collected blood samples in four mature Hereford bulls indicated the existence of a tonic mechanism for the secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH), i.e., their episodic release was not observed. Increased plasma concentrations of LH and FSH, however, were obtained in response to an intravenous injection of 500 µg of gonadotropin releasing hormone (GnRH). These gonadotropins showed similar secretory profiles after GnRH, but the relative magnitude of the LH response (30-fold) was considerably greater than that of the FSH response (sevenfold).

Concentrations of testosterone in jugular and spermatic vein blood were increased sevenfold …

The Welfare Effects Of Erosion Controls, Banning Pesticides, And Limiting Fertilizer Application In The Corn Belt: Comment, Clayton Ogg

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The recent Journal work by C. Robert Taylor and Klaus Frohberg was an impressive study from the standpoint of both the energy and imagination that must have gone into the model and the practical implications concerning the welfare effects of nonpoint pollution abatement. Yet, it appears that costs of nutrient management were considerably overestimated in the light of a number of experiments using techniques for controlling nutrient losses through proper timing of nitrogen fertilizer applications. Therefore. the model may have failed to represent the most cost effective techniques for reducing nitrogen pollution.

Research For Connecticut By The Storrs Agricultural Experiment Station

Storrs Agricultural Experiment Station

No abstract provided.

Bulletin 3990 - The Narrow-Leafed Lupin In Western Australia, J. S. Gladstones

Bulletins - 3000 - 3999

Lupins are new as a commercial crop, but may be very old as a food plant. Types of the Mediterranean white lupin (Lupinus albus L.) have been part-developed and used as a subsistence crop for 3 000 years or more. Likewise the pearl lupin (L. mutabilis Sweet) has been grown for many centuries in the Andean Highlands of South America. In both cases the seeds are boiled and steeped in water for several days to rid them of their bitter, somewhat toxic alkaloids. They are then used directly as a valued protein source in human diets.

Bulletin No 4007 - Grasses In South Western Australia, J G. Paterson

Bulletins 4000 -

IThe grasses comprise one of the world's largest families of flowering plants, with over 500 groups or genera containing well over 5000 individual types or species distributed throughout the world. About 125 groups have been recorded in Western Australia but it is probable that the list is far from complete. About one third of these have ° been introduced from overseas.

The purpose of this bulletin is to describe those grasses which are more commonly found in the south-west of Western Australia. Also, as many people are interested in knowing the name and nature of a grass when they find …

Evaluation Of Herbicides For Suppression Of Rhizome Growth From Johnsongrass (Sorghum Halepense L.) In Corn And Soybeans, John Oakes

Masters Theses & Specialist Projects

Johnsongrass (Sorghum halepense L.) presents a serious problem in the production of corn and soybeans in Kentucky.

Various rates of the thiocarbamates, dinitroanilines, carbamates, amides, ureas, and triazines were used in association with the crops corn (Zea mays L.) and soybeans (Glycine max L.) to determine the degree of suppression on rhizomatous johnsongrass infesting the previously named crops.

Suppression was determined by selecting areas within each treated plot, counting the number of culms, then harvesting johnsongrass rhizomes. Dry weights of rhizomes were then determined as a measure of rhizome suppression.

Results show that of …

Vertical Drainage In Field Cores, Larry G. Wells, R. W. Skaggs

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Acute And Chronic Effects Of Gonadotropin Releasing Hormone On Reproductive Characteristics Of Rams During The Nonbreeding Season, B. D. Schanbacher, D. D. Lunstra

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Acute and chronic effects of gonadotropin releasing hormone (GnRH) administration on reproductive characteristics of 32 rams have been assessed during the nonbreeding season. Rams injected intramuscularly with 50 µg of GnRH had elevated (P<.01)concentrations of serum testosterone and noticeably higher (60%) mating activities when compared to control animals injected with saline. Daily injections of GnRH resulted not only in higher testosterone concentrations and mating activity, but also in increased testes size (P<.05). The apparent change in testicular function may account for the improvement in semen quality which was observed in these animals. Although benefits were only slight for percentages of live sperm, normal sperm and sperm with normal acrosomes, sperm motility was markedly increased (P<.05).

These data suggest that reproductive performance in rams is related to testicular androgen secretion and that a spring decline in those characteristics normally associated with high fertility in the male can be lessened by chronic treatment with GnRH.

Bulletin No 4023 - Pasture Plants Of The Western Australian Shrublands, D G. Wilcox, J G. Morrissey

Bulletins 4000 -

The use of the shrubland pastures of Western Australia began in 1861 when Mr. W. Burges of the Bowes Station near Northampton sent a flock of sheep along the Greenough River to graze the country where Yuin station is today. Following his example, a number of other enterprising men established grazing areas along the river courses of this harsh and often drought stricken and forbidding land. By 1925, virtually all of the pastoral land of value in the mulga zone west of the Gibson Desert and the Great Victoria Desert had been developed, and by 1934, over four million sheep …

Production And Utilization Of Sunflower Food Plots At Shelbyville Wildlife Management Area, Illinois, Duane T. Dust

Masters Theses

Three sunflower (Helianthus annuus) fields from 3.2 ha to 1.0 ha in size, planted on the Shelbyville Wildlife Management Area, Illinois were analyzed for seed production and utilization by birds. Seed in heads and on the ground were sampled and species and numbers of birds in the fields were censused at two week intervals from September, 1976 to February, 1977. Decline in seed availability was most rapid in the smallest field and least rapid in the largest field. Fields and portions of fields adjacent to wooded cover were also utilized more rapidly. American goldfinch (Spinus tristis) …

Growth Analysis Of Tall Fescue Genotypes Differing In Yield And Leaf Photosynthesis, Wallace Wilhelm, C. J. Nelson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Leaf growth, dry matter distribution , and carbohydrate content of four tall fescue (Festuca arundinacea Schreb.) genotypes selected for high and low net C02 exchange (NCE) and forage yield were studied in controlled environments t o evaluate the leaf NCE-yield relationship. High yield genotypes produced greater amounts of all plant parts and carbohydrate than the low yield genotypes. Within each yield level the high NCE genotypes produced more dry matter and carbohxdrate. Leaf growth of all genotypes was linear throughout light and dark periods, but rates were 50% greater for high yield genotypes, RGR was similar for all genotypes. NAR …

Nitrate Reductase Activity In Tall Fescue, D. D. Randall, Wallace Wilhelm, R. F. Feuers, C. J. Nelson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

An in vitro assay for tall fescue leaf nitrate reductase activity (NRA) was established that required either O.5 % casein or polyvinylpyrrolidone in the extraction medium for maximal activity. Leaf NRA was proportional to light intensity and fertility levels. Mature tissue and high temperature decreased NRA. NRA showed significant genetic variability in broadly based genotypes and genotypes selected for photosynthetic rates and forage yields. However, progeny of the latter did not show significant genetic variability. High coefficients of variation (30-50%) among the heterogeneous progeny may have masked true genetic differences. No significant correlations were found between NRA and photosynthesis or …

Bulletin 3148 - Weeds In Lawns, G. A. Pearce, R. D. Royce

Bulletins - 3000 - 3999

IDENTIFICATION OF WEEDS IN LAWNS

Accurate identification of weeds is the first principle of weed control with modern chemicals. This is as true for weeds in lawns as any other weeds.

THE CONTROL OF WEEDS IN LAWNS

Most lawns have weeds growing in them at some time during the year and in some lawns weed control becomes a major problem.

Bacteria In The Air Of Housed Swine Units, L.F. Elliot, T.M. Mccalla, J.A. Deshazer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Two housed, swine-growing-finishing units were studied for numbers of total bacteria, fecal coliforms, Staphylococcus, and Salmonella in the air. At 30.5 and 122 cm from the floor, total colony-forming particles, as tested, averaged 3.4 x 10) and 1.3 x 105/m³ of air, respectively; whereas fecal coliform counts averaged 24 x 103 and 1.9 x 103/m³ of air, respectively. Only 41% of the organisms growing on Staphylococcus 110 medium tested as Staphylococcus. Of 458 Staphylococcus isolates, 5 were coagulase-positive. No Salmonella were detected in the air of the units tested.

Bulletin 4002 - Trickle Irrigation For Farms, K Cole

Bulletins 4000 -

The continued demand for, and use of trickle irrigation is proof of the inherent potential and performance of this form of irrigation.

Originally it was used in glasshouses and nurseries but it is now widely adapted to orchards, vegetable and other horticultural small crops and home gardens.

Although research is being actively pursued in the design and use of trickle irrigation it is now beyond the experimental stage as a technique and is an accepted and proven technique of watering many types of crop.

Bulletin No 3863 - Plants Which Cause Kimberley Horse Disease, A. L. Payne

Bulletins - 3000 - 3999

Crotalaria crispata and Crotalaria retusa (Rattlepod), two plants responsible for Kimberley horse disease*, are, unfortunately, fairly widespread throughout the Kimberleys. Both species are apparently toxic in all stages of growth.

This bulletin is to assist pastoralists to:-

• Identify the two plants;

• Recognise the type of country and conditions under which they grow; and

• Locate horse paddocks on country where the plants are least likely to occur.

Relationship Between Physiological And Morphological Characteristics And Yield Of Nondormant Alfalfa Clones, A. L. Foutz, Wallace Wilhelm, A. K. Dobrenz

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Alfalfa (Medicago sativa L.) breeders are constantly striving to improve the productivity of alfalfa. Yields have been increased primarily through the selection of plant materials resistant to insects and diseases. The objective of this study was to evaluate physiological characteristics which might be used as selection criteria in alfalfa improvement. Alfalfa clones were grown under field conditions on a Mojave clay loam soil. Carbon dioxide flux was evaluated in a closed system using an infrared gas analyzer. The physiological variables measured in these studies did not account for the varialion in yield among the clones. Apparent photosynthetic rates, dark …

Seasonal Changes In Sexual Activity And Serum Levels Of Lh And Testosterone In Finnish Landrace And Suffolk Rams, B. D. Schanbacher, D. D. Lunstra

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A procedure for assessing sexual activity (libido) in individual rams is described. Mating activity measured by this procedure and serum levels of luteinizing hormone (LH) and testosterone in Finnish Landrace and Suffolk rams was determined at 8-week intervals from October, 1974 through October, 1975. Seasonal changes were observed for serum LH, testosterone and libido index scores. Mating activity in rams was highest for both breeds during the peak breeding season (October) and declined 50% by late spring and summer before it increased the next October.

Serum LH concentrations were lowest in May (.54 ng/ml) and increased abruptly in July ( …