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Two experiments were conducted to evaluate recycled newspaper products as nutrient filters in the bottom of containers. In Expt. 1 with poinsettia, Euphorbia pulcherrima Willd. ex Klotzsch `Glory', three paper products were evaluated: ground paper, paper crumble, and paper pellets; each placed 2 or 3 cm deep in the bottom of containers, so that drainage holes were covered. Leachate samples were collected at the first irrigation after each liquid fertilization. Nitrate (NO3--N) and ammonium (NH4+-N) leachate concentrations were reduced up to 84% with recycled paper pellets, compared to the control (no paper). Recycled paper retained up to 732 mg of nitrogen (N) per container (paper pellets 3 cm deep). Shoot dry weight was reduced with paper pellets but was not affected by ground paper or paper crumble. In Expt. 2, `Freedom Red' poinsettias were grown with either single weekly applications of 500 mg·L-1 N from Peter's 20N-4.3P-16.6K, or 200 mg·L-1 N at each irrigation (2 or 3 times a week, as needed). Recycled paper treatments included paper crumble or paper pellets placed 2.5 cm deep in the bottom of containers, and a control without paper. Leachate NO3--N and NH4+-N concentrations were reduced up to 100% and 94%, respectively, 6 days after planting (DAP), and up to 57% and 50%, respectively, 25 DAP with paper crumble compared to nonpaper control. Paper pellets in the bottom of containers retained up to 776 mg N per container. Poinsettia shoot dry weight was lowest with paper pellets in the bottom of containers and continuous fertilization.

Two experiments were conducted to determine the effects of pelletized recycled paper mulch on container plant nutrition. In experiment 1 with Petunia floribunda Hort. ‘Midnight Madness’, 9 g (0.32 oz) of Osmocote 14N-6.2P-11.6K (14-14-14) was applied over or under 2.5 cm (1 in) of recycled paper pellet mulch, or to plants with no paper mulch (control). Leachate samples were collected after microirrigation. Both treatments with paper mulch reduced nitrate (NO3-N) and ammonium (NH4-N) levels in container leachate, compared to the control 21 days after planting (DAP). Shoot dry weight was reduced 53% and 70% for plants fertilized under and over the mulch, respectively, compared to the non-mulched control. At the end of the experiment 40–48% of the total N applied over or under mulch was retained by the recycled paper mulch. In experiment 2 with Petunia grandiflora Hort. ‘Ultra Blue’, mulch and three methods of fertilizer application (over mulch, under mulch, and incorporated in the substrate) were compared. Leachate NO3-N levels were reduced 72% or 68% with fertilizer placed over or under the mulch, respectively, when compared to a non-mulched topdressed treatment 21 DAP. When fertilizer was incorporated into the substrate, paper mulch reduced NO3-N leachate levels 87% compared to the non-mulched treatment. There were no significant differences in leachate NH4-N levels with fertilizer placed over or under the mulch when compared to a non-mulched control 21 DAP. When fertilizer was incorporated into the substrate, paper mulch reduced leachate NH4-N levels 82% compared to the non-mulched control. Shoot dry weight was 84 or 49% lower with fertilizer placed over or under the mulch, respectively, when compared to the topdressed, non-mulched treatment. However, plants grown with fertilizer applied under the mulch were 213% larger than plants with fertilizer applied over the mulch. When fertilizer was incorporated into the substrate, paper mulch reduced shoot dry weight 41% when compared to non-mulched plants. There were no differences between shoot dry weights of plants grown in non-mulched treatments with topdress fertilization or fertilizer incorporated.

Copper plays an important role in physiological and biochemical systems of animals. Copper deficiency in sheep produces ataxia, changes in color of pigmented wool, anemia, diarrhea and weight loss and is a major concern in the sheep industry because of indirect economic losses. There are several treatments against this disease but each of them has problems associated with usage. There is not an approved product for sheep in the United States for this deficiency. The efficacy of two copper oxide wire products (Coppinox ® and Copasure ® ) were tested in a flock of sheep with known deficiency. Three groups of 10 animals each, were used in a randomized block design. Animals were blocked by age. One group was dosed with 4 g of Coppinox, one with 4 g of Copasure and the third was left as an untreated control. Serum samples were taken monthly and copper levels were measured. The initial mean and range for all the animals on the study was 0.667 PPM and 0.16-1.06 PPM. The treated groups presented an increase in the mean copper serum concentration above the normal level (0.8 PPM) for five months. The untreated group had a mean below 0.8 PPM during the trial and showed clinical manifestation of the disease. None of the treated animals had clinical signs of copper deficiency or copper intoxication. Both formulations were efficient and safe for treatment of copper deficiency in sheep.

Milk samples were aseptically collected from 62 ewes at lambing from a flock of about 400 machine-milked Dorset and Polypay sheep. Of these, 24 ewes were sampled again at weaning upon entry into the milking group. An additional 18 ewes with clinical mastitis were sampled during lactation. Somatic cell counting was done on the milk from 59 ewes in the milking group. At lambing, milk from 29% of the ewes tested was culture-positive. Unilateral infections predominated. Coagulase-negative staphylococci (CNS) were found in 88% of the samples. Of the ewes sampled at both lambing and weaning, 33% were free of intramammary infections (IMI), 38% developed IMI during this period, 21% had spontaneous cures, and 8% had CNS IMI at lambing but were infected with coagulase-positive staphylococci (CPS) at weaning. Of the milking ewes with clinical mastitis, CPS were isolated in 66% of the milk samples while 22% had no growth. Nearly 90% of the milk samples had somatic cell counts of under 200 000 cells ml−1. The reason for the high incidence of CPS clinical mastitis in the milking group was not determined. Somatic cell counts in this milking flock of sheep were similar in magnitude to those found in non-mastitic dairy cows but lower than those for milking goats. This suggests that somatic cell count standards for cow milk could probably be applied to sheep milk. The somatic cell counts indicated a low level of IMI in this milking flock, reflective of the preventive mastitis measures used.

Lambs from a university sheep flock and kids from a commercial goat dairy were injected with a bacterin containing Curynebacterium pseudotuberculosis ( 1 mg whole cells and 50 fig muramyl dipeptide in 10% light mineral oil) twice i.m. in the thigh, 1 month apart. All animals were then exposed to naturally infected adults under field conditions. Serum antibody titers to C. pseudotuberculosis, determined regularly up to 19 months in all animals vaccinated in 1990 and up to 7 months in all animals vaccinated in 1991, rose sharply after vaccination and remained higher (P

The purpose of this study is to describe a developmental defect of the caudal cervical and cranial thoracic vertebrae in 11 purebred Colombia lambs. The lambs were either affected at birth, or developed the condition within the first 18 days of age. Cervicothoracic kyphosis, with a compensatory cervical lordosis and ataxia were common; 8 lambs had abnormal head posture, characterized by inability to lift the head from the ground. One lamb had rigid head and neck, and had to move the entire body to look to the left or right. Neurological signs included ataxia, tetraparesis, diminished conscious proprioception, and increased patellar and triceps reflexes. One lamb had inspiratory stridor because of compression of the trachea in the area overlying the abnormal vertebrae (cervical vertebrae 6 [C6] and 7 [C7]). Radiographic and pathological abnormalities included malalignment and malarticulation of the caudal cervical and cranial thoracic spine, rounded cranioventral margins in the bodies of vertebrae C7 and T1, wedging of the intervertebral disc spaces between C6 and T1 vertebrae, and hypoplasia of the dens. Pathological changes in the soft tissues included hypoplasia of the cervical epaxial and hypaxial musculature, with associated focal areas of myodegeneration. Mild Wallerian axonal degeneration, compatible with a mild cord compression syndrome, was found in 3 lambs in the cervicothoracic spinal cord adjacent to the vertebral anomalies. The concentrations of copper and selenium in blood, plasma, or tissues were normal in 10 of 11 lambs. All but one of the lambs in which pedigree information was provided were genetically related. Siblings born as twins to 5 of the affected lambs were normal, but both lambs from one twin pregnancy were affected. Owners reported that breeding stock had been shared among the ranches. Because of the close familial relationships of the affected lambs, the condition is suspected to have a hereditary basis.

Hepatitis delta virus (HDV) is an important cause of acute and chronic liver disease. Current medical therapies are unable to effectively eradicate HDV infections. Research into the molecular virology of the HDV life cycle has revealed a fascinating collection of biology. These insights are now beginning to be translated into new potential treatment strategies. For example, an essential step in the virus assembly process involves the post-translational lipid modification of a specific HDV protein, namely prenylation of large delta antigen. Preventing prenylation abolishes virus particle formation. Drugs capable of specifically inhibiting prenylation have been developed for use in humans. These agents represent a new class of antiviral agents, with HDV as a first target. Here, a brief review of the HDV life cycle emphasizing the role of prenylation is presented along with implications for drug development and therapy.

A previously described bluetongue virus (BTV) serogroup polymerase chain reaction (PCR) assay was applied to clinical samples. The sensitivity of the BTV serogroup PCR was increased by the use of non- radioactive chemiluminescent hybridization. Unfractionated whole blood samples from rams experimentally inoculated with cell culture-adapted BTV- 11 UC-8 were analyzed by virus isolation (VI) on Vero cells and PCR. VI and PCR were in agreement, with the exception of 3 blood samples that were VI negative and PCR positive. In semen spiked with BTV- 11 UC-8, PCR detected as little as 1.6 x 10 2 plaque-forming units of BTV/ ml of semen. BTV in the spleen of a sheep submitted for necropsy for suspect BTV infection was detected by both PCR and VI in embryonated chicken eggs. BTV PCR with nonradioactive chemiluminescent hybridization resulted in a level of sensitivity comparable to that of VI and likly more sensitive than VI on Vero cells for blood. This BTV PCR has great promise for rapid, sensitive, and specific detection of active BTV infection in a variety of clinical samples. Bluetongue virus (BTV) is an arthropod-borne or- bivirus that infects wild and domestic ruminants. Blue- tongue virus infection is economically significant be- cause of morbidity and mortality among clinically affected animals and restrictions on international movement of animals and germplasm that have not been certified BTV free. 14 Animal and germplasm protocols for BTV-free cer- tification are currently being reevaluated (B.I. Osburn, personal communication). Competitive enzyme-linked immunosorbent assay (cELISA) formats will prove useful for determination of exposure to BTV. However determination of active BTV infection in seropositive animals and their germplasm will still require a costly, lengthy protocol involving virus isolations and serol- ogy. Polymerase chain reaction (PCR), 13 a technique used to exponentially amplify targeted nucleic acid se- quences, has great promise for facilitating detection of active BTV infection. Sensitive detection of the viral RNA from a wide spectrum of BTV serotypes from the United States and Israel using PCR amplification of viral RNA and radioactive dot hybridization de- tection of the BTV-specific PCR product have been reported. l This paper outlines application of the pre- viously reported BTV PCR protocol, modified with nonradioactive hybridization detection of the BTV- specific PCR product, to the detection of BTV in blood, semen, and tissue.

Ovine contagious foot rot may cause lameness in sheep, resulting in decreased wool growth and low weight gain. Affected neonatal lambs are difficult to treat, and treatment is labor intensive; thus, a method of prevention is warranted. Vaccination of ewes with a multivalent vaccine in an oil adjuvant induced development of antibody to the somatic O antigen of Bacteroides nodosus, and this antibody was detected in serum of newborn lambs after consumption of colostrum from the vaccinated ewes. Antibody titers were determined in 48 unvaccinated ewe/lamb pairs, and in 50 once-vaccinated and 78 twice-vaccinated pairs. Serum and colostrum O-agglutinin titers to B nodosus were determined by a microtitration agglutination test. Lambs from vaccinated ewes had significantly (P less than 0.05) higher O-agglutinin titers than those from unvaccinated ewes, and double vaccination of ewes resulted in the highest potentially protective titers (greater than 1:2,400) in ewes and lambs.

Data from a commercial sheep enterprise were used to derive correction factors to be applied to 120-day lamb weaning weights. These correction factors made use of information on lamb sex, weaning age, birth and rearing status, and age of dam. The factors obtained were compared with commonly used standard factors, and there was enough difference to justify development of within flock factors.

A prospective cohort study was designed to describe the patterns and to determine the factors associated with the risk of rectal prolapse in a commercial swine herd in California, USA. Thirty (1.0 per cent) of 2862 pigs prolapsed between 12 and 28 weeks of age with the peak incidence occurring in 14- to 16-week-old pigs. The overall prolapse rate was 9.1 cases per 100,000 days at risk. Prolapse rates were highest during the winter and autumn months. Other factors associated with an increased risk of prolapse were maleness (relative risk 2.3) birthweight less than 1000 g (relative risk 3.4) Yorkshire boar A (relative risk 2.8) and dams of litter number 1 (relative risk 14.9), 2 (relative risk 8.2) and 3 (relative risk 9.8). No evidence was found to support the hypothesis that diarrhoea and coughing are factors associated with a risk of prolapse.

Prophylactic efficacy of 100 mg of long-acting oxytetracycline (OTC) given IM to neonatal pigs within 12 hours of birth was evaluated in a swine herd. The herd had a history of increased neonatal mortality, diarrhea, foot abscess, and arthritis in nursing pigs. Two trials were conducted in which liters and individual pigs were the treatment groups of interest. In both trials, OTC treatment failed to reduce mortality, diarrhea, or arthritis or the need for subsequent antimicrobial therapy (P greater than 0.05). Preweaning weight gains were not increased (P greater than 0.05) in treated pigs. However, in the individual pig trial, foot abscess rates were significantly (P = 0.01) lower in treated pigs (3.7%) than in nontreated pigs (8%). Aerobic bacteria isolated from pigs with diarrhea, arthritis, or foot abscess had minimum inhibitory concentrations for OTC greater than or equal to 64 micrograms/ml or were classed as resistant on the basis of disk-diffusion tests.

The epidemiology and economics of Brucella ovis control in a hypothetical, commercial sheep flock (100 rams and 2,500 ewes) were investigated. The investigation consisted of an epidemiologic simulation model, reported here, and a decision-tree analysis, reported in a companion paper. The epidemiologic model was designed to simulate the transmission and persistence of B ovis in a ram flock during the mating season as well as the nonmating (isolation) season. A constant contact rate was selected for the nonmating season and a varying contact rate was selected for the mating season to reflect changes in numbers of ewes in estrus. These contact rates were used to evaluate all possible combinations of 5 control alternatives for flock infection rates ranging from 0% to 38%. Vaccination was found to be more effective as a control strategy when the prevalence of flock infection was high (greater than 15%); however, it did not substantially reduce B ovis transmission when the prevalence of flock infection was low (less than 10%). The effect of increasing vaccine efficacy from 40% to 80% had minimal effect on incidence of new cases. The speed with which B ovis could be eradicated depended on the initial prevalence of infection and the screening tests used (palpation, semen testing for leukocytes, and ELISA). All combinations of screening tests verified the usefulness of palpation. Simulation model results indicated that it may be feasible to eradicate B ovis from flocks with moderate to high (10% to 38%) prevalence of infection by culling on the basis of 2 sequential tests.(ABSTRACT TRUNCATED AT 250 WORDS)

The epidemiology and economics of Brucella ovis control in a hypothetical, commercial sheep flock (100 rams and 2,500 ewes) were investigated. The investigation consisted of an epidemiologic simulation model, reported in a companion paper, and a decision-tree analysis, reported here. It was predicted from the simulation model that B ovis could be eradicated successfully in 2 test periods (less than 1 year) from a flock by using intensive screening and culling. A computerized decision-tree program was used to determine the economically optimal control strategy among several alternatives. Two versions of the program were used to determine the optimal alternative, based on minimizing the expected monetary loss (deterministic) and minimizing the associated risk (stochastic). The economically optimal alternative was to screen the rams by means of palpation, semen testing, and ELISA prior to the mating season. Rams positive to any test were culled. After the mating season was completed, the optimal action was to use ELISA for the remaining rams and to cull all that were ELISA positive. The cost of this alternative was approximately $6,150, or less than one half the annual cost of a vaccination program ($12,800) or no program ($13,550). Continuing palpation and semen testing were considered worthwhile on the basis of detecting new cases of B ovis infection and in maintaining high flock fertility. Similarly, the cost of annual use of ELISA was small (approximately $100), compared with the potential cost of not detecting a new case of B ovis infection.