Iowa State University Veterinary Medical Alumni Association Annual Meeting

The annual meeting of the Iowa State University Veterinary Medical Alumni Association (ISUVMAA) was held at the Marriott Hotel, Des Moines at noon on January 28, 1996. There were 49 members in attendance

Serpulina pilosicoli competitive exclusion product

A competitive exclusion product is described which includes a substantially pure culture of the bacterium species Serpulina pilosicoli, or a genetic equivalent thereof. When administered to an animal, the S. pilosicoli colonizes the cecal wall to prevent the colonization of other harmful bacteria, thereby preventing disease

Air Quality and Hen Health Status in Three Types of Commercial Laying Hen Houses

Environmental conditions and bird health are important elements in assessment of animal welfare for laying hen housing systems, but limited information is available comparing different types of systems. Three types of laying hen houses - caged high-rise, caged manure-belt, and cage-free floor-raised - were monitored for temperature, relative humidity, carbon dioxide, and atmospheric ammonia during winter and summer conditions in Iowa. During winter conditions, temperature and ammonia concentrations were maintained at a more comfortable level for the caged facilities. During summer conditions, temperature showed the least rise above ambient for the cage-free facilities, and ammonia was maintained at similar levels for all housing types. Assessment of hen health status revealed differences in pathogen frequency between housing systems for winter and summer, but not conclusively in favor of one system over another. The results of this observational study indicate that each system may offer benefits during specific weather conditions. Further monitoring to quantify the benefits of each system should be completed

Air quality and bird health status in three types of commercial egg layer houses

In this field observational study, 3 types of laying-hen houses, namely, high-rise (HR), manure-belt (MB), and cage-free floor-raised (FR), were monitored for air temperature, RH, CO2 , and atmospheric NH3 under winter and summer conditions in Iowa. Under winter conditions, the HR and MB houses had more comfortable temperature and NH3 levels (mean 24.6 and 20.6°C, and maximum 9 to 24 ppm of NH3 , respectively) than the FR houses (mean 15.5°C and maximum 85 to 89 ppm of NH3 , respectively), and house temperature varied more with outside conditions. Under summer conditions, house temperature showed the least increase above ambient in the FR houses (mean 0.3°C vs. 4.7 and 1.2°C for the MB and HR houses, respectively), and NH3 levels were similar for all housing types (mean 3 to 9 ppm). Examination of the hen health status revealed differences in pathogen prevalence between housing systems for winter and summer, but not conclusively in favor of one system over another. Results of this study indicate that the benefits of each system were season dependent. Further monitoring of the environment, bird health, and production performance over an extended period (e.g., 1 yr) to quantify the benefits and limitations of each system is warranted. Information of this nature will aid in optimizing hen housing systems for enhanced bird welfare and sustained production efficiency for the egg industr

Dietary Spray-Dried Bovine Plasma Protein Improves Growth Performance and Breast-Meat Yield of Broilers Raised in a High-Antigen Environment

Dietary bovine spray-dried plasma protein (SDPP) had no effects on growth performance or breast-meat yield of broilers raised in a low-antigen environment (Exp. 1). Dietary bovine SDPP, fed at intermediate levels throughout the growth period, improved growth performance and breast-meat yield of broilers raised in a high-antigen environment (Exp. 2). Further research is needed to determine the optimal inclusion level of bovine SDPP and to determine if SDPP should be fed throughout the growth period or in early growth phases only

Rapid Aerosol Transmission of Salmonella Among Turkeys in a Simulated Holding-Shed Environment

Once turkeys arrive at Midwest processing plants, they are usually held in large open-sided sheds for 1 to 4 h, waiting to be unloaded. In hot, humid weather, large fans are used to cool the birds. The resultant air currents distribute a significant amount of dust to the turkeys. The dust created in this environment could be a factor in the number of Salmonella-contaminated turkeys entering slaughter plants. The objective of this study was to determine if rapid transmission of Salmonella in turkeys could occur from exposure toSalmonella-contaminated dust similar to what may be experienced in holding sheds or in other high-dust environments prior to slaughter. In the first experiment, trials of 3 different concentrations of Salmonella (1.2 × 109, 2.6 × 107, and 2.6 × 105 cfu/g) were conducted to determine if transmission ofSalmonella enterica serovar Typhimurium var. typhimuriumχ4232 to turkeys 2 to 4 h after aerosol exposure to contaminated feces is possible. Results showed that turkeys became infected after 2 h of exposure to airborne-contaminated feces with a concentration level of 2.6 × 105 cfu of SalmonellaTyphimurium/g. In the second experiment, consisting of 3 trials, 1 bank (5 cages wide and 3 cages high) of turkeys (n = 15 birds per trial) was exposed to another bank of cages of S. Typhimurium-inoculated (n = 15) birds for 2 to 4 h using a fan similar to the type in processing-plant cooling sheds. Results from this experiment demonstrated that birds could be contaminated with S.Typhimurium after 2 h of exposure. Results of both studies implicate contaminated dust as a route of rapid airborne transmission of Salmonella in turkeys. Processes that generate significant dust prior to slaughter should be regarded as critical control points for Salmonella

Detection of Salmonella Enteritidis in Pooled Poultry Environmental Samples Using a Serotype-Specific Real-Time–Polymerase Chain Reaction Assay

While real-time–polymerase chain reaction (RT PCR) has been used as a rapid test for detection of Salmonella Enteritidis in recent years, little research has been done to assess the feasibility of pooling poultry environmental samples with aSalmonella Enteritidis–specific RT PCR assay. Therefore the objective of this study was to compare RT PCR SalmonellaEnteritidis detection in individual and pooled (in groups of two, three, and four) poultry environmental drag swab samples to traditional cultural methods. The drag swabs were collected from poultry facilities previously confirmed positive forSalmonella Enteritidis and were cultured according to National Poultry Improvement Plan guidelines. Initial, SalmonellaEnteritidis–specific RT PCR assay threshold cycle cutoff values of ≤36, ≤30, and ≤28 were evaluated in comparison to culture. The average limit of detection of the RT PCR assay was 2.4 × 103 colony-forming units (CFUs)/ml, which corresponded to an average threshold cycle value of 36.6. Before enrichment, samples inoculated with concentrations from 102 to 105 CFUs/ml were detected by RT PCR, while after enrichment, samples inoculated from 100 to 105 CFUs/ml were detected by RT PCR. Threshold cycle cutoff values were used in the subsequent field trial from which Salmonella Enteritidis was cultured in 7 of 208 environmental samples (3.4%). Individual samples were 99.0%, 100%, and 100% in agreement with the RT PCR at threshold cycle (Ct) cutoff values of ≤36, ≤30, and ≤28 respectively. The agreement for pooled samples also followed the same trend with highest agreement at Ct ≤ 28 (pool of 2  =  100.0%, pool of 3  =  100.0%, pool of 4  =  100.0%), midrange agreement at Ct ≤ 30 (pool of 2  =  99.0%, pool of 3  =  100.0%, pool of 4  =  100.0%), and lowest agreement at Ct ≤ 36 (pool of 2  =  98.1%, pool of 3  =  97.1%, pool of 4  =  98.1%). In conclusion, regardless of the level of pooling after tetrathionate enrichment, sensitivity was very good, and results would be comparable to what would have been found with individual culture or individual RT PCR at Ct ≤ 36

A Federal and State Transport Plan for Movement of Eggs and Egg Products from Commercial Egg Production Premises in a High-Pathogenicity Avian Influenza Control Area

The FAST Eggs Plan is a voluntary plan for commercial egg producers intended to facilitate business continuity following an outbreak of HPAI. Participation in the FAST Eggs Plan will reduce the time required for regulatory officials to determine that it is safe for eggs and egg products from noninfected chickens located within a control area to move into market channels located outside the control area. The FAST Eggs Plan has 5 components. First, a Biosecurity Checklist for Egg Production Premises and Auditors includes biosecurity measures that will help prevent introduction of avian influenza virus onto egg-production premises. Second, registration with the National Animal Identification System is required for participating egg-production premises, and the premises location is verified by GPS coordinates. Third, epidemiological data are used to determine whether an egg farm has been exposed directly or indirectly to birds and other animals, products, materials, people, or aerosols from premises on which HPAI virus has been confirmed. Fourth, the absence of HPAI virus on FAST Eggs Plan premises is verified by negative RRT-PCR assay results from a minimum of 5 dead chickens selected from those that die each day from each house on the farm. Fifth, the risk of exposure to HPAI virus is estimated by use of an equation based on risks not mitigated by quarantine and distance from infected premises