The objective of this study was to assess the relationships among temperature, moisture, carbon-to-nitrogen (C:N) ratio, space per cow, and bacterial counts from bedding material collected from compost bedded pack (CBP) barns. A field survey of 42 routinely aerated CBP barns was conducted in Kentucky between October 2010 and March 2011. Two bedding material samples of 1,064.7 cm(3) each were collected during a single site visit from 9 evenly distributed locations throughout each barn and thoroughly mixed to create a composite sample representative of the entire CBP. Bacterial counts were determined for coliforms, Escherichia coli, streptococci, staphylococci, and Bacillus spp. University of Kentucky Regulatory Services (Lexington) laboratory personnel performed nutrient analyses to determine moisture, carbon, and nitrogen contents. Surface and 10.2-cm pack depth temperatures were collected for each of the 9 evenly distributed locations and the mean calculated to produce a composite temperature. Space per cow was calculated as the total CBP area divided by number of cows housed on the CBP. The GLM procedure of SAS (SAS Institute Inc., Cary, NC) generated models to describe factors affecting bacterial counts. Bacterial counts were 6.3 ± 0.6, 6.0 ± 0.6, 7.2 ± 0.7, 7.9 ± 0.5, and 7.6 ± 0.5 log 10 cfu/g of dry matter for coliform, Escherichia coli, streptococci, staphylococci, and Bacillus spp., respectively. Composite temperature, CBP moisture, C:N ratio, and space per cow had no effect on coliform counts. Escherichia coli reached a peak concentration when the C:N ratio was between 30:1 and 35:1. Staphylococci counts increased as ambient temperature increased. Streptococci counts decreased with increased space per cow and composite temperature and increased with increasing ambient temperature and moisture. Streptococci counts peaked at a C:N ratio ranging from 16:1 to 18:1. Bacillus spp. counts were reduced with increasing moisture, C:N ratio, and ambient temperature. Mastitis-causing bacteria thrive in similar conditions to that of composting bacteria and microbes, making elimination of these at higher temperatures (55 to 65°C) difficult in an active composting environment. Producers must use recommended milking procedures and other preventative practices to maintain low somatic cell count in herds with a CBP barn.

a b s t r a c tThe objective of this study was to describe relationships among compost bedded pack barn (CBP) measurements (moisture, internal temperature, nutrient content, and bedding bacterial counts), ambient weather conditions, and udder health. Data was collected every 2-weeks (n¼ 25 visits) from 8 Kentucky dairy farms with CBP from May 2013 to May 2014. A single observer scored 50 cows per farm for hygiene and collected compost internal temperature, moisture, and compost samples from 9 evenly distributed areas in each barn. Weighted average somatic cell count (SCC), high SCC prevalence (HSP), and reported clinical mastitis incidence (RCMI) were collected from herd records and milking personnel.Compost internal temperature increased with increasing maximum barn temperature (BT). Compost moisture content decreased with increasing BT. Herd hygiene score decreased with increasing BT and increased with increasing compost moisture content. Herd SCC and HSP both increased with increasing BT but were unaffected by compost measurements. As compost internal temperature increased, staphylococci, streptococci, and bacilli species growth in the pack area decreased and coliform species growth increased. Low CBP moisture and high CBP temperature reduced bacteria levels. Cow hygiene and udder health indicators had a stronger relationship with BT than with CBP internal temperature and moisture.

Keywords:Sand bedded freestall barn Compost bedded pack barn Mastitis Lameness a b s t r a c tThe objective of this study was to assess differences between compost bedded pack (CBP) and sand freestall barns (SFB) for mastitis indicators (herd clinical mastitis, SCC, high SCC prevalence (% of herd Z200,000 cells/mL SCC), and BTSCC), and locomotion, hygiene, and hock scores. This study was conducted on commercial Kentucky dairy farms using CBP (n¼ 8) or SFB (n¼7) as the primary lactating cow housing facility from May 2013 to May 2014. To indicate good management practices, eligible herds had to maintain a yearly mean SCC o 300,000 the year before enrollment in the study. Milk samples were collected from quarters that presented clinical signs of mastitis as identified by milking personnel. Each herd was visited biweekly (n¼26 visits) over the study period. Each visit included evaluating 50 cows per herd for hygiene, locomotion, and hock scores. Somatic cell count (SCC) and high SCC prevalence (percentage of animals in each herd with a test day SCC Z 200,000 cells/mL) were collected from Dairy Herd Information Association (DHI, Raleigh, NC). Bulk tank SCC from each pick up was gathered from each dairy's milk purchaser. Bulk tank SCC from each pick up for all Kentucky herds on DHI regardless of SCC or housing type from January 2013-2014 was requested from the Kentucky Milk Quality Safety Branch to determine differences among all bedding types without selecting for herds enrolled in DHI. Overall, no differences between 8 CBP and 7 SFB selected based on SCC existed for herd locomotion, hygiene, or hock health. No differences were observed for the main effects of housing, maximum temperature humidity index, or hygiene score on SCC, high SCC prevalence, clinical mastitis incidence, or bulk tank SCC for 8 CBP and 7 SFB Kentucky herds. Similarly, for Kentucky DHI herds, bulk tank SCC was not different among herds using CBP, freestall barns, and tie-stall barns. Herds using CBP alongside freestall barns had the lowest bulk tank SCC in Kentucky. These results indicate that, when managed properly, CBP can provide a housing environment comparable to SFB. Freestalls, tie-stalls, and compost bedded pack barns for all herds on DHI had similar bulk tank SCC.

The API Staph-Ident system was evaluated as a means for identifying the species of bovine strains of staphylococci routinely isolated from quarter-milk samples. The species identity of 314 of 581 (54%) isolates of staphylococci was correctly determined by this method. The API Staph-Ident system was more accurate in correctly identifying Staphylococcus alureus (93.9%) than in correctly MATERIALS AND METHODS Bacterial isolates. During a 20-month period, 581 gram-positive catalase-positive cocci of bovine origin were obtained by our laboratory from several sources. A total of 25 isolates were obtained by swabbing the distal end of the streak canal of 14 cows in the University of Kentucky dairy herd during their dry period. The remaining isolates were obtained from the following sources: 96 were activated from freeze-dried cultures of isolates obtained from quarter foremilk samples from the University of Kentucky dairy herd in 1969 (25, 26), 383 were from quarter foremilk samples obtained from the University of Kentucky dairy herd during the 20-month period of this study, 32 were from two private dairy herds in Kentucky with a high incidence of mastitis (18, herd A; 14, herd B), 37 were from J. W. Pankey, North Louisiana Hill Farm Experiment Station, Homer, La., and 9 were from K.

The DMS Staph-Trac system was evaluated as a means for identifying the species of bovine strains of staphylococci routinely isolated from quarter-milk samples. The species identity of 83 of 91 (91.2%) isolates of staphylococci was correctly determined by this method. One isolate could not be identified by this system. The Staph-Trac system was able to distinguish between Staphylococcus hyicus and Staphylococcus epidermidis. We obtained a higher percentage of correct identifications with the DMS Staph-Trac system (91.2%) than we did in a previous study with the API Staph-Ident system (45.1%), using the same isolates (Langlois et al.,

Thirty-three biochemical characteristics were compared for 855 staphylococci isolated from human (93) and bovine sources (762). Differences in the predominant Staphylococcus species present and biochemical characteristics of species were observed for isolates from bovine milk and human clinical sources as well as between milk isolates obtained during the 1960s and 1980s from the same herd. All isolates were bacitracin-resistant and 98% were lysostaphin-sensitive. Approximately 31% of S. hyicus strains were coagulase-positive. Thermonuclease activity was observed for strains other than S. aureus. Milk strains were more salt tolerant than human strains. Carbohydrates tended to be utilized by a greater percentage of milk strains than human strains within a given species. Many milk isolates failed to utilize glycerol in the presence of 0.4 μg erythromycin/mL. The results of this study indicate that the source of isolates may influence the predominant species present and species biochemical characteristics. These differences in species characteristics may affect results obtained for identification of nonhuman isolates with rapid identification systems where the data bases are generally based on human clinical isolates.

Hams were cured and aged by three methods, two using nitrite and nitrate but with long or short aging times at controlled temperature, and one using no nitrite or nitrate with ambient aging temperature. Hams were sliced, vacuum-packaged and stored at O"C, 10°C or 21°C for 8 wk and examined weekly for white film, aroma, and aerobic, staphylococci, lactobacilli, yeast and mold counts. White film development was erratic. Aroma was closely related to aerobic counts. At 0°C bacterial counts and aroma remained normal for 8 wk. At 10°C many packages had acceptable counts and aroma at 8 wk but some were unacceptable by 4 or 5 wk. At 21°C many slices were unacceptable microbiologically and sensorily by 3 wk. Storage at or near 0°C is recommended for long shelf life.

A greater percentage of DNase-positive strains was detected with DNase test agar than with DNase test agar containing 0.005% methyl green or 0.005% toluidine blue (P < 0.01). No significant differences were obtained in the percentage of phosphatase-positive strains with the four methods compared. On the basis of ease of use, P agar containing para-nitrophenylphosphate disodium (0.495 mg/ml) would be the preferred method for determining phosphatase activity of staphylococci.