All posters on Milliron X

Genetic analysis of bovine papillomas

2024-09-19T00:00:00+00:00

Bovine papillomavirus (BPV) is a major cause of reproductive failure in cattle. In bulls, penile papillomas caused by BPV may cause reluctance to breed, and is always a cause to fail an animal on a breeding soundness exam. Historically, it has been thought that BPV was transmitted via direct contact and could be controlled by managing clinically presenting animals in the herd, but more recent evidence suggests alternative modes of transmission. BPV has been found repeatably in clinically healthy animals, and in non-cutaneous secretions including milk, blood, urine and semen. Currently, no commercially available BPV vaccine uses isolated viral particles and naturally occurring virus does not produce cross-protective immunity. In order to develop a proper vaccine for penile papillomas further studies are required to understand the epidemiology of BPV in herds. While vulvar, cutaneous, and mammary papillomas have been genotyped in recent years, this information is not available for penile papillomas. In this study there were 31 submissions, collected from 7 states, NE, KS, NY, TX, AL, MO and SD (14 different cattle operations) Samples were collected between August of 2022 and April 2024. Twenty-two submissions were penile papillomas and with pooling of samples represented over 50 penile papillomas. Samples were metagenomically sequenced at the Kansas State Veterinary Diagnostic Lab, and the genotype of each sample was determined using the phylogenetic analysis. The clade of each sample was determined by aligning consensus sequences of the L1 gene (used for both for phylogeny and as a vaccine target) using MAFFT and a maximum-likelihood phylogeny generated in Mega X. Analysis found that all penile papilloma submissions were composed of BPV type 2, with one sample showing co-infection with BPV type 1. Conversely, cutaneous and teat papillomas had BPV genotypes that were more variable with genotypes of 1,2,7,12,14,29 and 40. These results indicate that BPV type 2 and type 1 provide a unified target for bovine penile papilloma vaccine development.

Metagenomic analysis of rumen populations in week-old calves as altered by maternal late gestational nutrition and mode of delivery

2019-06-12T00:00:00+00:00

Early colonization of the rumen microbiome is critical to host health and long term performance. Factors that influence early colonization include maternal factors such as gestational nutrition and mode of delivery. Therefore, we hypothesized that late gestational nutrition and mode of delivery would influence the calf rumen microbiome. Our objectives were to determine if nutrient restriction during late gestation alters the calf rumen microbiome and determine if ruminal microbiome composition differs in calves born vaginally versus caesarean. Late gestating Angus cows were randomly allocated to one of three treatment groups: control (CON; n = 6), caesarean section (CS; n = 4), and nutrient restricted (NR; n = 5), where CON were fed DDGS and hay to meet NRC requirements and calved naturally; CS were fed similarly to CON and calves were born via caesarean section; and NR were fed at a level to reduce BCS by 1.5-2.0 points over the last trimester compared to CON and calved naturally. Rumen fluid was collected via oral lavage prior to partition from cows and at d 7 from calves. Microbial DNA was isolated from the rumen fluid and metagenomic shotgun sequencing was performed using the Illumina HiSeq 2500 platform. Sequence data were analyzed using Metaxa2 for taxonomic assignment followed by QIIME1 and QIIME2 to determine differential abundance and alpha- and beta-diversity differences. There were no significant differences in alpha-diversity as measured by shannon index across treatment groups for cows (P = 0.239), but there were significant differences for calves (P = 0.015). Similarly, there were no significant differences in beta-diversity as measured by the bray-curtis dissimilarity matrix for cows (P = 0.059), but there were significant differences for calves (P = 0.007). Alpha-diversity differed (P < 0.001) between cows and calves, with cows having increased species richness compared to calves. Beta-diversity also differed (P = 0.001) between cows and calves. At total of 410 taxa were differentially abundant (P < 0.01) between cows and calves. These results suggest that the mature rumen microbiome of cows is able to withstand changes in feed intake, however the calf microbiome is susceptible to alteration by maternal factors. These data also suggest that there may be opportunities to develop management strategies during late gestation that influence calf health and performance long-term.

Measuring Diffusion of Trichlorethylene Breakdown Products in Polyvinylalginate

2018-10-29T00:00:00+00:00

Trichloroethylene (TCE), a toxic and carcinogenic contaminant, presents unique challenges for cleanup because of its water solubility, density, and volatility. Bioremediation of TCE is a promising cleanup method; however, metabolism of TCE results in acid generation that inhibits remediating microorganisms. Calcium alginate(CA)-polyvinylalcohol (PVA) hydrogels show promise for protecting remediating microbes, however diffusion of TCE or its byproducts through these polymers is unknown. To measure the effective diffusion coefficient of TCE and byproducts through hydrogel membranes, we used a modified diaphragm cell. Measured effective diffusion coefficient of each species was (cm ² /s × 10⁶ ): 14.0 ± 1.91 for H⁺ ions, 12.4 ± 1.64 for TCE, 7.83 ± 0.54 for cis-1,2-dichloroethylene (DCE), and 4.68 ± 4.14 for vinyl chloride. These results aid in engineering biobeads and suggest that CA-PVA hydrogel blends are effective in slowing diffusion of protons, buffering acids produced by trichloroethylene metabolism, and remains suitable for encapsulation of microorganisms involved in bioremediation.

Measuring diffusion of protons in polyvinyalginate

2018-07-31T00:00:00+00:00

Trichloroethylene (TCE) is a toxic and carcinogenic contaminant that presents unique challenges for cleanup because of its density and volatility. Use of microorganisms may be a promising remediation method, however metabolism of TCE results in acid buildup, which consequently impedes the ability of microorganisms to perform this remediation. Polyvinylalginate (PVA) shows promise as a useful shield for microorganisms carrying out bioremediation of TCE by surrounding them in a protective biofilm-like layer, however, key information is missing which relates diffusion of TCE or its metabolic products through PVA. To measure the effective diffusion coefficient of H⁺ ions through a PVA membrane cross-linked with boric acid and calcium ions, we used a modified diaphragm cell. We found the effective diffusion coefficient to be 1.40 × 10^-5 ± 1.91 × 10^-6 cm² s, a nearly seven-fold decrease in diffusivity compared to protons in water, with an unexpected significant but as of yet unquantified adsorption capacity. These results suggest that polyvinylalginate is effective in slowing diffusion of protons and buffering these acids produced by trichloroethylene metabolism, and remains suitable for encapsulation of microorganisms involved in bioremediation.