Jim Cullor

• University of California, Davis

California is the largest agricultural producer in the United States and local dairy industry produces 21.5% of the national milk supply. There are 1470 dairies, 1789 million dairy cows and a total annual milk production of 18 million metric tons. The amount of dead cows to be disposed of is remarkable in intensive farming and it increases in perio...

Abstract The objective of this study was to investigate the antibacterial properties of chitosan acetate (CA), sodium dodecyl sulfate (SDS), lactic acid (LA) and their synergism when combined against a nontoxigenic strain of Escherichia coli O157:H7. Treatments that significantly reduced the concentration of E. coli O157:H7 in vitro by more than tw...

The dairy industry under current pasteurization conditions (15 s at 72°C) and sanitary standards achieves a safe product with excellent quality. In an ever-competitive market there is still a need to improve product quality and extend shelf life of dairy products to increase competitiveness and open up new markets. In an attempt to test the effect...

The aim of this study was the evaluation of selected lactic acid bacteria (LAB) starter culture of dairy origin in the production of nitrite-free low-acid fermented venison (Dama dama) sausage (salame di daino) produced in a small-scale plant in Umbria (Italy), and their effect on microbiological, physico-chemical and sensorial properties of the pr...

All hosts, including humans, can be infected by any one of the three forms of the parasite Toxoplasma gondii that correspond to three morphological stages: tachyzoite, bradyzoite, and sporozoite form. Felids are definitive hosts for T. gondii, which is an intracellular pathogen that infects a wide range of warm-blooded intermediate hosts. Toxoplasm...

Dry-off, and the period around parturition, are associated with increased susceptibility to intramammary infections in dairy cows. The immunological profiles of mammary gland secretions during these periods are not well described. The objective of the present study was to better characterize association(s) between chronic subclinical Environmental...

Raising a heifer calf to reproductive age represents an enormous cost to the producer. Poor neonatal growth exacerbates the costs incurred for rearing, and use of blood variables that may be associated with poorly growing calves may offer predictive value for growth and performance. Thus, the principal objective of the present study was to describe...

A quantitative microbial risk assessment was constructed to determine consumer risk from Staphylococcus aureus and staphylococcal enterotoxin in raw milk. A Monte Carlo simulation model was developed to assess the risk from raw milk consumption using data on levels of S. aureus in milk collected by the University of California-Davis Dairy Food Safe...

The objective of this study was to determine if viable Mycobacterium avium subsp. paratuberculosis (MAP) was present in waste milk delivered and fed to calves on California calf ranches. Four calf-raising facilities in the Central Valley of California that fed pasteurized waste milk to calves were enrolled. Pre- and post-pasteurization waste milk s...

Mycobacterium avium paratuberculosis (MAP) is thought to be associated with Crohn's disease in humans. Since Johne's disease affects dairy and beef cattle, meat may be a possible route of transmission of MAP to humans. In this study, we compared a rapid multiplex real time PCR assay and conventional culture to detect MAP in ground beef. The real ti...

To determine the efficacy of the chelating agent EDTA on microbial growth, separate cultures of two streptococcal bovine mastitis isolates, Streptococcus agalactiae and Streptococcus uberis, were exposed to known concentrations of EDTA. Bacterial cultures of 10(8) CFU/ml were exposed to concentrations of EDTA ranging from 30 to 100 mM in an in-vitr...

Pseudomonas aeruginosa is a major cause of severe bacterial keratitis and remains a difficult clinical entity to treat successfully with the current arsenal of antimicrobial agents. Defensins are small cationic peptides with broad in vitro antimicrobial activity and are potential ocular therapeutic agents. The authors characterised the in vitro act...

A novel real-time fluorescent multiplex polymerase chain reaction (PCR) assay for detecting and discriminating between bovine, ovine, and caprine contaminates in cattle feed was developed that simultaneously performs quality control monitoring on both the DNA extraction process and the level of PCR inhibition in the final DNA extract in a single PC...

The addition of human milk components with intrinsic antimicrobial activity to livestock milk by genetic engineering has the potential to benefit milk safety and production as well as the health of the lactating animal. As a model for the dairy cow, we generated transgenic goats that expressed human lysozyme in their milk at 68% of the levels found...

A modified culture method using C18-carboxypropylbetaine (CB-18) and microscopic screening was evaluated for time to and limit of detection of Mycobacterium avium subsp. paratuberculosis (MAP) in raw milk. Bulk-tank milk samples were spiked with six different concentrations (10(1) to 10(6) CFU/mL) of MAP. Samples were processed using two different...

A modified forensic DNA extraction and real-time fluorescent polymerase chain reaction assay has been evaluated for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) in bovine fecal samples using primers and fluorescent resonance energy transfer (FRET) probes targeting the IS900 gene sequence of MAP. DNA was successfully extracted...

Radiofrequency (RF) power was investigated as a new, physical (nonchemical), thermal process to disinfect wastewater from dairy and animal facilities. Samples (n = 38) from 8 dairy, 2 calf, and 3 swine facilities in California were collected over a 3-yr period and characterized for their dielectric properties, chemical composition, and suitability...

Environmental bacteria have emerged over the past few years to become significant causes of mastitis. Bacteria in this group are often reported by practicing veterinarians to be increasingly resistant to intramammary therapy and responsible for elevated bulk tank somatic cell counts. The purpose of this study was to determine the extent of associat...

Radiofrequency (RF) heating was investigated as an alternative to cooking, drying or chemical disinfection for the preservation of fishmeal and shown to be a highly effective process without any detectable effects, particularly on proteins, lipids or in vivo digestibility. The uniform and deep penetration of RF waves resulted in rapid and homogeneo...

Subclinical mastitis is a costly disease of the dairy industry and is presently diagnosed by somatic cell counts. Current detection methods for cell counts include automated machines at remote laboratory sites and subjective farm tests. An alternate method was developed to quantify somatic cells using a rapid assay and sensor that were designed to...

A real-time fluorescent polymerase chain reaction assay for detecting prohibited ruminant materials such as bovine meat and bone meal (BMBM) in cattle feed using primers and FRET probes targeting the ruminant specific mitochondrial cytochrome b gene was developed and evaluated on two different types of cattle feed. Common problems involved with PCR...

To compare the results of regulatory screening and confirmation assays with those of high-performance liquid chromatography (HPLC) in the detection of ceftiofur metabolites in the tissues of culled dairy cattle. 17 lactating Holstein dairy cows. Daily IM injections of ceftiofur sodium were administered at a dose of 2.2 mg of ceftiofur equivalents/k...

The purpose of this trial was to examine the potential of a new Escherichia (E) coli J-5 mutant strain bacterin to reduce the severity of clinical disease caused by subcutaneous challenge with endotoxins of Gram-negative bacteria in calves. Day-old to 3-day old calves (n = 40 per study phase) were randomly assigned to either of two treatment groups...

The practice of incorporating mammalian protein in ruminant feeds was banned in the United States in 1997 as a measure to avoid transmission of bovine spongiform encephalopathy (BSE). A sensitive means of identifying the banned additives in feeds would be by detection of species-specific DNA using the polymerase chain reaction (PCR). However, probl...

Subclinical mastitis is a costly disease of the dairy industry and is presently diagnosed through somatic cell counts. Current detection methods include automated machines at remote lab sites and subjective cowside tests. An alternate method was developed to quantify somatic cells using a rapid assay and sensor that were designed to be easily amena...

Staphylococcus aureus is an important cause of mastitis in cows. The ability of S. aureus strains to produce one or more enterotoxins in milk and dairy products is linked to staphylococcal food poisoning. To determine whether staphylococci causing bovine mastitis could cause human foodborne intoxication, the production of staphylococcal enterotoxin...

mRNA profiles of IL-8 in the bovine mammary gland were investigated using newly developed TaqMan^® real-time PCR systems. The transcription of bovine IL-8 between middle and late stages of the lactation period revealed no significant differences. The constant transcription of IL-8 at both stages could be related to the low need for neutro...

TaqMan real time PCR was used to study the transcriptional activity of the bovine IL-2, IL-6, IL-12p40, IFN-gamma, TNF-alpha and granulocyte-monocyte colony stimulating factor of whole milk cells in bovine mammary gland experimentally infected with Staphylococcus aureus. Cytokine transcriptional activity was monitored at 7, 24 and 32 h Post-infecti...

In the present study, a multiplex RT-PCR-based assay for simultaneous detection and differentiation of North American serotypes of bluetongue (BT) virus (BTV) and epizootic hemorrhagic disease (EHD) virus (EHDV) in cell culture and clinical samples was developed. Two pairs of primers (B1 and B4) and (E1 and E4) were designed to hybridize to non-str...

To evaluate a spiral plating and microscopic colony counting technique to hasten the quantitation of Mycobacterium paratuberculosis. Broth and milk cultures of M. paratuberculosis were spirally plated onto Middlebrook agar plates and microscopically counted at 8 and 14 days of incubation. The same plates were recounted at 27-28 days of incubation w...

The objectives of this study were to develop an assay to quantify somatic cells in raw milk using fluorescent double-stranded DNA (dsDNA) markers and to develop a sensor implementing the detection chemistry. Three methods were used to extract DNA from somatic cells in milk. Method one involved a fat removal step via centrifugation and a commercial...

Because of concerns that some potentially dangerous microorganisms may survive conventional heat pasteurization of milk and because the heat needed to sterilize milk affects marketability, the ability to efficiently cold pasteurized milk may become more desirable. In this pilot study, we investigated the use of pulsed ultraviolet (PUV) laser light...

Vocal communication mediates social relationships in many mammalian species and can be particularly important in mother–infant interactions. Mammalian species in general and cows in particular exhibit a strong mother–infant bond that is frequently expressed through vocal exchanges among mothers and their infants. Several species produce calls that...

Antibodies directed toward gram-negative core antigens (GNCAs) have been demonstrated in many mammalian species but to date are unexamined in any avian species. An enzyme-linked immunosorbent assay with phenol-killed whole cell Escherichia coli J5 was used to assess the presence of serum antibodies directed toward GNCAs in chickens. The first exper...

The cytokine mRNA profiles of the bovine mammary gland were investigated using newly developed TaqMan real-time polymerase chain reaction systems (Applied Biosystems, Foster City, CA, USA). Transcriptional activity of six cytokines, interleukin (IL)-2, IL-6, IL-12, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and granulocyte-macrophag...

Environmental streptococci are frequently isolated from bovine mastitis in dairy cows with only limited information available on the antimicrobial susceptibility of these organisms. A total of 362 environmental streptococci isolated from cases of bovine mastitis from the central San Joaquin Valley of California over a 3-yr period were used in the s...

Here we present a novel methodology to quantitate bovine cytokines and growth factors contributing to immunity against bacterial infections of the mammary gland in cattle. Real-time TaqMan PCR systems were developed to overcome limitations of conventional quantitative PCR methods. The TaqMan method is based on the cleavage of fluorescent dye-labele...

Staphylococcus aureus causes many diseases including cellulitis, keratitis, osteomyelitis, septic arthritis and mastitis. The heptapeptide RIP has been shown to prevent cellulitis in mice, which was induced by S. aureus strain Smith diffuse. Here we show that RIP can also significantly reduce the overall pathology and delay the onset of disease sym...

The daily farm is a 'Food Manufacturing Facility'. Everyday it produces raw milk, dairy beef and liquid and solid nutrients. Since food safety begins on the farm, this mini-ecosystem must be managed on a daily basis for animal health and well-being, public health, environmental health and the financial well-being of the operation. An approach, term...

Performance of the Delvo-X-Press beta-lactam antibiotic assay was examined using bulk-tank milk samples and milk samples from individual cows. Bulk-tank milk samples fortified with bovine lactoferrin at a concentration of 1 mg/ml or more consistently tested positive. False-positive results were also obtained from bulk-tank milk samples fortified wi...

Oxidative metabolic burst activity by Asian elephant (Elephas maximus) heterophils and Holstein cattle (Bos taurus) neutrophils was indirectly evaluated by measuring the oxidation of nonfluorescent intracellular 2',7'-dichlorofluorescein (DCFH) to fluorescent 2',7'-dichlorofluorescein (DCF) with flow cytometry. The results were recorded as mean cha...

beta-Defensins are microbicidal peptides implicated in host defense functions of phagocytic leukocytes and certain surface epithelial cells. Here we investigated the genetic structures and cellular expression of BNBD-4, -12, and -13, three prototypic bovine neutrophil beta-defensins. Characterization of the corresponding cDNAs indicated that BNBD-4...

β-Defensins are microbicidal peptides implicated in host defense functions of phagocytic leukocytes and certain surface epithelial cells. Here we investigated the genetic structures and cellular expression of BNBD-4, -12, and -13, three prototypic bovine neutrophil β-defensins. Characterization of the corresponding cDNAs indicated that BNBD-4 (41 r...

Various antimicrobial cationic peptides have been isolated from the granules of bovine neutrophils. One of these peptides is only 12 amino acids in length and is called a dodecapeptide bactenecin. A monoclonal antibody to the synthetic bovine dodecapeptide bactenecin was produced, characterised and used in an immunofluorescent assay to assess the p...

To evaluate the ability of commercially available Escherichia coli J5 bacterin to protect rabbits from experimental challenge with Pasteurella multocida. 40 P multocida-free New Zealand White rabbits. Rabbits were assigned to 1 of 4 groups of 10 rabbits each. Three of the groups were inoculated SC with J5 bacterin at 8 weeks old. Inoculation was re...

The objectives were to simultaneously assess mycotoxins and bacteria in feed and to estimate coliform and Escherichia coli concentration in water offered to growing hogs on commercial facilities. A total of 333 pigs from 10 commercial facilities were used at 28 d of age. Facilities were visited throughout the production cycle at 28, 56, 84, 112, an...

To determine the seroprevalence of antibodies to gram-negative core antigens (GNCA) in specific-pathogen-free (SPF) rabbits (ie, free of Pasteurella multocida) and rabbits of undefined bacterial status (conventional). Serum samples were obtained from 7 groups of rabbits. The SPF rabbits comprised 2 adult groups and 1 immature group, whereas the 4 g...

To determine percentage of false-positive test results for assays used by regulatory agencies to detect antibiotic residues in tissues. Prospective study. 426 dairy cows. Dairy cows scheduled for culling that were identified as being unlikely to have antibiotic residues in tissues on the basis of strict inclusion criteria were used. A sample of kid...

Reactive thrombocytosis is an increase in the circulating thrombocyte count secondary to a physiologic process within the body, often an infection. Reactive thrombocytosis is different than primary or essential thrombocytosis which is usually related to myeloproliferative neoplasia. Essential thrombocytosis is most common in adults, whereas reactiv...

On or before Jul 29, 2011 this sequence version replaced gi:5410321, gi:5410322, gi:5410323.

PCR amplification technology for the detection of epizootic hemorrhagic disease virus (EHDV) ribonucleic acid in cell culture and clinical specimens was developed. With oligoribonucleotide primers selected from genome segment 10 of EHDV serotype 1 (EHDV-1), which codes for two nonstructural proteins (NS3 and NS3a), the PCR-based assay resulted in a...

Processed poultry litter intended for dairy cattle feed was collected on 13 dairy ranches in the San Joaquin Valley of California and analyzed for the presence of significant bacterial pathogens associated with clinical disease in cattle or foodborne disease in humans. Litter samples were collected from the surface and interior of the litter piles...

This is the first report of a rapid technique for the isolation of elephant heterophils form ethylene diamine tetra-acetic acid (EDTA) anticoagulated whole blood using hetastarch sedimentation and Percoll discontinuous gradient centrifugation modified from equine neutrophil isolation techniques (Sedgwick et al. 1986; Pycock 1987). Heterophil purity...

A nested polymerase chain reaction (PCR)-based assay, for detection of bluetongue virus (BTV) ribonucleic acid in cell culture and tissue samples, was developed. Two pairs of oligonucleotide primers (BTV1 and BTV4 and BTV2 and BTV3), selected from non-structural protein 1 (NS1) gene of BTV-17, were used for the nested PCR in two amplification steps...

The antimicrobial properties of standard human lysozyme and the milk of transgenic mice expressing human lysozyme were investigated using bacterial strains important to the dairy industry. Standard human lysozyme was found to be effective at significantly slowing the growth of the milk cold-spoilage organism Pseudomonas fragi (P < 0.001), of a clin...

This study investigated the effect of naturally acquired bacterial infection of the bovine mammary gland on subpopulations of T lymphocytes and cytokine expression in milk. Twenty-nine lactating cows with mastitis were compared to 12 normal animals. CD4+ lymphocytes represented a significantly greater percentage of the milk-derived lymphocytes in i...

Oxidative metabolic burst activity by heterophils from orange-winged Amazon parrots (Amazona amazonica amazonica) was indirectly evaluated by measuring the oxidation of non-fluorescent intracellular 2′,7′-dichlorofluorescin (DCFH) to fluorescent 2′,7′-dichlorofluorescein (DCF) with flow cytometry. Heterophils were isolated from whole blood samples...

To assess the number of bacteria and presumptive antibiotic residues in milk fed to calves and to identify those bacteria and the antibiotic susceptibility of selected bacterial strains. Cross-sectional prospective study. 189 samples obtained from 12 local dairies. Samples of waste milk and milk-based fluids (eg, milk replacer, colostrum, bulk-tank...

Summary Consumers and regulatory officials are becoming increasingly aware of the human health risk of the presence of micro-organis ms or chemicals in the agricultural environment. Providing 'on-farm food safety' programmes which address the daily management of the production unit with regard to animal health and well-being, public health and envi...

Consumers and regulatory officials are becoming increasingly aware of the human health risk of the presence of micro-organisms or chemicals in the agricultural environment. Providing 'on-farm food safety' programmes which address the daily management of the production unit with regard to animal health and well-being, public health and environmental...

In vitro experiments were conducted to determine the influence of source of neutrophils (individual calves) and calf age on phagocytic and oxidative burst activities of neutrophils isolated from 106 clinically healthy Holstein-Friesian calves. Calves were categorised by age into four groups: group A, 3–7 days; group B, 8–14 days; group C, 15–21 day...

Blood samples from adult orange-winged Amazon parrots (Amazona amazonica amazonica) were collected to develop a rapid and efficient technique for isolating pure populations of morphologically intact and functional heterophils. In addition, normal haematological parameters for the orange-winged Amazon parrots (n=20) were established and found to be...

Non-vaccinated Holstein female calves, 3–31 days old (n=106) were examined in order to determine peripheral blood lymphocyte subpopulations and haematological values. The relative populations of lymphocytes were determined using flow cytometry. Monoclonal antibodies were used to identify BoCD2+, BoCD4+, BoCD8+, B-cells,γ/δ T-cells, and monocytes/ne...

To investigate intramammary infections in llamas, identify the pathogens responsible, and determine whether effects of intramammary infection could be detected by use of mastitis indicator tests commonly used for cows. Observational study. 100 llamas on 10 farms. Milk samples were evaluated by bacterial culturing and by determination of somatic cel...

To evaluate alterations in lymphocyte subpopulations, CBC results, and clinical signs in neonatal calves inoculated with 3 commercially available proprietary multiple-antigen vaccines containing known quantities of endotoxin. Prospective, randomized controlled field trial. 36 healthy Holstein heifer calves between 3 and 31 days old. Vaccines were a...

A new family of cysteine-rich antimicrobial peptides from bovine neutrophils was isolated and characterized. Thirteen structurally homologous peptides were purified to homogeneity from a granule-rich cytoplasmic fraction of purified blood neutrophils. The complete sequences of the peptides were determined by a combination of enzymatic digestion, Ed...

Thirty heifers were fed a ration containing 30 g monensin/ton. Fecal, urinary and seral samples were collected at varying intervals prior to and after initiating administration of the monensin-containing feed, and monensin concentrations were determined using a modified indirect enzyme immunoassay. Fecal samples contained measurable (micrograms/g;...

A new family of cysteine-rich antimicrobial peptides from bovine neutrophils was isolated and characterized. Thirteen structurally homologous peptides were purified to homogeneity from a granule-rich cytoplasmic fraction of purified blood neutrophils. The complete sequences of the peptides were determined by a combination of enzymatic digestion, Ed...

Microbial keratitis caused by Pseudomonas aeruginosa is the most common contact lens associated corneal infection. Cecropins are microbicidal peptides isolated from the hemolymph of the Cecropia moth. Previous in vitro studies have demonstrated their efficacy against a broad spectrum of ocular pathogens. This study was designed: a) to evaluate the...

As infectious disease problems continue to plague food animal practice, an improved understanding of the causative agent and the pathophysiology of disease events will facilitate the development of prevention and treatment strategies. In food animals, gram-negative bacteria are responsible for clinical conditions that range from simple diarrhea to...

A pair of studies designed to assess the clinical safety and potency of hyperimmune plasma administration was undertaken in neonatal calves. Bovine plasma from Holstein heifers hyperimmunized with a mutant Escherichia coli O111:B4 (J5) vaccine which had a geometric mean (GM) immunoglobulin G (IgG) ELISA titer of 3.5 x 10(4), was administered subcut...

Hyperimmunized bovine plasma containing antibodies to a mutant Escherichia coli O111:B4 (J5) was used to conduct a prospective double-blind clinical trial to evaluate its efficacy as an immunotherapy to bovine neonates in field conditions. Two- to three-day-old calves (N = 150) were randomized into three groups (n = 50) to receive (1) no plasma (NP...

For two large California dairy herds with twice daily milking, 171 infected quarters of lactating cows with mild clinical mastitis were randomly assigned to one of three treatment groups. Group A (50 cows) was treated with 62.5 mg of intramammary amoxicillin every 12 h for three milkings. Group C (50 cows) was treated with 200 mg of intramammary ce...

The objective of this study was to test the hypothesis that PGF2alpha is associated with abortion and changes in plasma Zn, Cu, and Fe concentrations in cows and mares in their first trimester of pregnancy. Eleven pregnant cows were infused with endotoxin (n = 5) or endotoxin plus an inhibitor of cycloxygenase, flunixin meglumine (n = 6). Blood was...

One thousand neonatal calves, allocated in a factorial design into four groups, were vaccinated subcutaneously with two doses each of either killed Escherichia coli (0111:B4) J5 bacterin or a UC Davis modified live, genetically altered (aro-) Salmonella dublin vaccine, or both, or with a placebo. In this prospective double-blind study to determine...

Autoclaved distilled water samples were inoculated with L. monocytogenes strain V7 and strain VPH-1, and incubated aerobically, at 30 C for 48 hours. Each strain was tested individually, and growth curves were determined at 1, 2, 3, 4, 5, 21, 24, and 48 hours. The growth or survival of L. monocytogenes was similar for both strains, with survivors a...

The phenotype of bovine milk lymphocytes was investigated and compared to peripheral blood lymphocytes using monoclonal antibodies specific for bovine leukocyte differentiation antigens and flow cytometry. T lymphocytes traffic selectively into bovine milk while B lymphocytes represent a minor population in milk by comparison to peripheral blood. T...

The 10-point Milk and Dairy Beef Quality Assurance Program was developed collaboratively by the National Milk Producers Federation and the American Veterinary Medical Association and is designed to promote and document the responsible use of antibiotics in the dairy industry. One area of emphasis in this program is testing of individual animals for...

Cecropins are antimicrobial peptides (30-35 amino acids) isolated from the hemolymph of the cecropia moth. Previous studies have demonstrated their antimicrobial efficacy against a variety of pathogens, including both gram-positive and -negative bacteria, fungi, protozoa, and enveloped viruses. To assess their therapeutic potential against ocular p...

Current control methods are not effective in eliminating various mastitis pathogens, and antimicrobial therapy introduces some risk of contaminating dairy products with antibiotic residues. Individuals involved in animal agriculture are sensitive to their responsibility to prevent antibiotic residues from entering the food chain. The ability to und...

Immunization and immunotherapy for mastitis are active areas of investigation. The past decade has seen development of effective and economical R-mutant vaccines for gram-negative mastitis. These vaccines doubtless will prove beneficial on well managed dairies that have eradicated contagious mastitis pathogens. Development of vaccines for other mas...

For three California dairy herds with bulk tank SCC < 200,000/ml, twice daily milking, and no mastitis vaccine, 254 quarters with mild clinical mastitis were randomly assigned to three groups. Group A (n = 74) was treated with 62.5 mg of intramammary amoxicillin every 12 h for three milkings. Group C (n = 75) was treated with 200 mg of intramammary...

Milk from 172 commercial cows with mild to moderate clinical mastitis was tested with five antibiotic residue detection assay systems. One hundred cows were treated with one of two intramammary beta-lactam antibiotics, and the remaining 72 cows were treated with intramuscular oxytocin. Milk samples were collected pretreatment, twice after therapy,...