Large sticky traps for capturing house flies and stable flies in dairy calf greenhouse facilities

Large sticky traps were evaluated for stable fly, Stomoxys calcitrans (L.), and house fly, Musca domestica L., (Diptera: Muscidae) capture under field conditions in 5 dairy calf greenhouse facilities in New York. The farm with the highest stable fly capture had the highest house fly capture, and the farm with the lowest stable fly capture had the lowest house fly capture, suggesting that fly management practices greatly influenced trap captures. In general, stable fly populations, as reflected by increased trap capture, generally rose during the summer. Numbers of flies counted on calves did not increase, however, suggesting that the traps greatly reduced the potential stable fly pressure on the calves as the fly population increased. Estimated number of stable flies and house flies captured during this 10-wk study exceeded 142,000 and 900,000, respectively. Producers were generally pleased with the trap performance and most felt that these traps reduced flies in their calf greenhouses to acceptable levels.     

Factors associated with dairy farmers' satisfaction and preparedness to adopt recommendations after veterinary herd health visits

Herd health and production consultancy are important aspects of the modern dairy veterinary practice; therefore, veterinary farm visits will likely be more successful if veterinary practitioners communicate effectively and meet farmers' expectations. Objectives were to assess dairy farmers' satisfaction with veterinary advisors and their perceived preparedness to adopt veterinary advice. Furthermore, we assessed whether farmers' satisfaction and preparedness to adopt advice were associated with specific predictor variables; that is, general (demographic) factors of veterinarians or farmers, communication tools used by veterinarians, and veterinarians' affective attributes during the farm visit. Audio-video recordings of 14 dairy veterinarians during 70 herd health and production management farm visits were analyzed using the Roter interaction analysis system. Demographic data, farmers' satisfaction, and farmers' preparedness to adopt advice were obtained by using questionnaires. Overall, farmers were satisfied with their veterinarian's communication during farm visits and 58% of farmers felt “absolutely” prepared to follow veterinary recommendations. Based on multivariable regression analysis, farmers' satisfaction was positively associated with their level of education and the amount of talk the veterinarian dedicated to counseling the farmer. However, satisfaction was negatively association with the ratio between veterinarian talk and farmer talk. In addition to various demographic variables, farmers' preparedness to adopt veterinary advice was positively associated with their satisfaction. Other predictor variables for farmers' preparedness to follow recommendations included increased veterinary counseling and frequent herd data discussions, whereas there was a negative relationship between number of farmer questions and dominance of the veterinarian during the farm visit. Identification of factors influencing farmers' satisfaction and preparedness to adopt advice will make veterinary communication more effective and could inform training of veterinarians in communication.     

Development of a novel walk-through fly trap for the control of horn flies and other pests on pastured dairy cows

A prototype walk-through fly vacuum system, designed to remove horn flies Haematobia irritans (L.) (Diptera: Muscidae) from cattle, was developed and tested for efficacy. The study was conducted during 4 fly seasons over 17 consecutive weeks each year within the months of May through September at 1 dairy research herd in the coastal plain of North Carolina. Additional data on horn flies, as well as face flies (Musca autumnalis) and stable flies (Stomoxys calcitrans), were collected during 1 yr from 7 commercial pasture-based and organic dairy farms in the piedmont region of North Carolina. The number of flies observed on animals in the pasture was compared with the number of flies collected in the trap. Studies were initiated after horn fly densities had met or exceeded a threshold of 200 flies per animal. The vacuum trap removed between 1.3 and 2.5 million flies annually from the research station cattle. Most fly removal occurred during the first few weeks of operation and maintained densities below threshold thereafter. Cattle using the fly trap at the research farm had only about 28% the number of horn flies as untreated cattle, and reductions ranged from 67.5 to 74.5% across the 4-yr study. In addition to large numbers of horn flies, traps placed on commercial dairies during 1 yr collected stable flies, face flies, and house flies, all species with differing behavior and larger in size than horn flies. The estimated cost of running the trap is $72 per season at commercial rates of $0.12 per hour and an expected 4 h of daily operation during the time of milking. Use of a vacuum system as described herein has potential as a cost-effective method in reducing populations of parasitic flies in pasture-based dairy production systems without the use of insecticides.     

Occurrence and transport of tetracycline, sulfonamide, quinolone, and macrolide antibiotics in the Haihe River Basin, China

The occurrence and transport of 12 antibiotics (from the tetracycline, sulfonamide, quinolone, and macrolide families) was studied in a 72-km stretch of the Haihe River, China, and in six of its tributaries. Aqueous and sediment samples were analyzed by HPLC-MS/MS. Sulfonamides were detected at the highest concentrations (24-385 ng/L) and highest frequencies (76-100%). Eight of the 12 antibiotics likely originated from veterinary applications in swine farms and fishponds, and concentrations at these sources (0.12-47 μg/L) were 1-2 orders of magnitude higher than in the effluent of local wastewater treatment plants. Sulfachloropyridazine (SCP) was detected in all swine farm and fishpond samples (maximum concentration 47 μg/L), which suggests its potential usefulness to indicate livestock source pollution in the Haihe River basin. Hydrological and chemical factors that may influence antibiotic distribution in the Haihe River were considered by multiple regression analysis. River flow rate exerted the most significant effect on the first-order attenuation coefficient (K) for sulfonamides, quinolones, and macrolides, with higher flow rates resulting in higher K, probably due to dilution. For tetracyclines, sediment total organic matter and cation exchange capacity exerted a greater impact on K than flow rate, indicating that adsorption to sediments plays an important role in attenuating tetracycline migration. Overall, the predominance of sulfonamides in the Haihe River underscores the need to consider regulating their veterinary use and improving the management and treatment of associated releases.     

Measuring antimicrobial use on dairy farms: A method comparison cohort study

Antimicrobial use on UK dairy farms is measured for surveillance purposes, with veterinary sales data as a proxy for use. Two other methods of recording use have been used commonly on-farm: medicine waste bins and farm medicine records. However, none of these methods has been validated to measure antimicrobial use. The objective of this research was to assess agreement between the 3 most common methods for measuring on-farm antimicrobial use with a predetermined reference method on UK dairy farms. Antimicrobial use was measured prospectively on 26 UK dairy farms using medicine waste bins into which participants placed all discarded medicine packaging for a 12-mo period. At the end of 12 mo, farm medicine records and veterinary sales data were obtained retrospectively for participating farms. The reference method used was based on pre- and poststudy inventories combined with veterinary sales data. We investigated the systematic difference between the mean on-farm antimicrobial use measured by each of the 3 methods and a reference method, using one-way repeated-measures ANOVA models. Reliability and clinical relevance of the agreement between each pair of methods was quantified using the concordance correlation coefficient (CCC) and the Bland-Altman method, respectively. When compared with the reference method, veterinary sales data had excellent reliability for injectable antimicrobials and intramammary antimicrobials [95% confidence interval (CI) of CCC > 0.90] and moderate to excellent reliability for other antimicrobials (95% CI of CCC: 0.68–0.97). Medicine waste bins had good to excellent reliability for injectable (95% CI of CCC: 0.84–0.99), and intramammary products (95% CI of CCC: 0.78–0.94) and no agreement for other forms of antimicrobial. Farm medicine records did not agree for any form of antimicrobial when compared with the reference method. The use of veterinary sales data as a proxy for on-farm antimicrobial use in the UK represented excellent statistical reliability and offered clinically good agreement with the reference method when used to measure injectable antimicrobials. This study applies to the UK context and included a relatively small number of farms. However, these results have research and policy implications, both nationally and internationally, and are essential in accurately quantifying agricultural antimicrobial use to inform both animal and human health.     

Distribution of Salmonella in swine production ecosystems

The objective of this 2-year field survey was to sample multiple ecological compartments within swine production systems to identify potential sources of Salmonella infection for swine. Twelve single-site production systems within Illinois were identified by slaughter sampling to have detectable Salmonella in swine and therefore selected for study. There were four visits to each farm during a 5-month period. Fecal samples were obtained from swine and other wild and domestic mammals. Arthropods and environmental samples of feed, water, pen floors, boots, and bird feces were also collected. All 8,066 samples obtained were cultured to detect Salmonella. Salmonella was detected on 11 of the 12 farms. There were 206 positive cultures, including samples from swine (83), pen floors (54), boots (32), flies (16), mice (9), cats (3), and birds (3). Swine shedding Salmonella in feces were detected on 9 of the 12 farms. The more Salmonella-abundant ecological compartments were cats (12% of samples positive), boots (11%), bird feces (8%), flies (6%), and mice (5%); 2.1% of 4,024 swine samples were positive. All 221 feed samples were negative for Salmonella. There was a correlation between a farm having a high prevalence of shedding Salmonella in pigs and a high abundance on pen floors, flies, and boots. The most common serotypes detected were Derby, Agona, Worthington, and Uganda, which were distributed throughout the ecosystem, suggesting widespread transmission across ecological compartments. The ubiquitous distribution of Salmonella suggests that an effective control strategy must target multiple compartments of the swine production ecosystem.     

Prevalence of Salmonella in diverse environmental farm samples

The development of suitable intervention strategies to control Salmonella populations at the farm level requires reliable data on the occurrence and prevalence of the pathogen. Previous studies on Salmonella prevalence have focused on acquiring data from specific farm types and/or selected regions. The purpose of this study was to evaluate the distribution of this pathogen across a variety of farm types and regions in order to generate comparative data from a diverse group of environmental samples. Farm samples (n = 2,496) were collected quarterly from 18 different farms across five states (Tennessee, North Carolina, Alabama, California, and Washington) over a 24-month period. The participating farms included beef and dairy cattle operations, swine production and farrowing facilities, and poultry farms (both broiler chicken and turkey). The samples were analyzed for the presence of Salmonella by means of the U.S. Food and Drug Administration's Bacteriological Analytical Manual methods optimized for farm samples. Salmonella isolates were characterized by automated riboprinting. Salmonella serovars were recovered from 4.7% of all samples. The majority of positive findings were isolated from swine farms (57.3%). The occurrence of Salmonella was lower on dairy farms (17.9%), poultry farms (16.2%), and beef cattle farms (8.5%). The most commonly isolated serovar was Salmonella Anatum (48.4%), which was isolated notably more frequently than the next most common Salmonella serovars, Arizonae (12.1%) and Javiana (8.8%). The results of this study suggest that significant reservoirs of Salmonella populations still exist on swine production facilities and to a lesser extent in other animal production facilities. Data showed that the surrounding farm environment could be an important source of contamination.     

Process audits versus product quality monitoring of bulk milk

Assessment of milk quality is based on bulk milk testing and farm certification on process quality audits. It is unknown to what extent dairy farm audits improve milk quality. A statistical analysis was conducted to quantify possible associations between bulk milk testing and dairy farm audits. The analysis comprised 64.373 audit outcomes on 26,953 dairy farms, which were merged with all conducted laboratory tests of bulk milk samples 12 mo before the audit. Each farm audit record included 271 binary checklist items and 52 attention point variables (given to farmers if serious deviations were observed), both indicating possible deviations from the desired farm situation. Test results included somatic cell count (SCC), total bacterial count (TBC), antimicrobial drug residues (ADR), level of butyric acid spores (BAB), freezing point depression (FPD), level of free fatty acid (FFA), and milk sediment (SED). Results show that numerous audit variables were related to bulk milk test results, although the goodness of fit of the models was generally low. Cow hygiene, clean cubicles, hygiene of milking parlor, and utility room were positively correlated with superior product quality, mainly with respect to SCC, TBC, BAB, FPD, FFA, and SED. Animal health or veterinary drugs management (i.e., drug treatment recording, marking of treated animals, and storage of veterinary drugs) related to SCC, FPD, FFA, and SED. The availability of drinking water was related to TBC, BAB, FFA, and SED, whereas maintenance of the milking equipment was related mainly to SCC, FPD, and FFA. In summary, bulk milk quality and farm audit outcomes are, to some degree, associated: if dairy farms are assessed negatively on specific audit aspects, the bulk milk quality is more likely to be inferior. However, the proportion of the total variance in milk test results explained by audits ranged between 4 and 13% (depending on the specific bulk milk test), showing that auditing dairy farms provides additional information but has a limited association with the outcome of a product quality control program. This study suggests that farm audits could be streamlined to include only relevant checklist items and that bulk milk quality monitoring could be used as a basis of selecting farms for more or less frequent audits.     

A study of the knowledge, attitudes, and behaviors of French dairy farmers toward the farm register

Health organizations worldwide have advocated that treatment records be required to show that antibiotics are used prudently by veterinarians and farmers alike. In 2000, the French government passed legislation making a farm register mandatory for all farms that raise animals for food production. The farm register is a comprehensive record designed to track all animal movements, treatments, and veterinary interventions on the farm. We conducted a survey to assess the knowledge, attitudes, and behaviors of dairy farmers toward the farm register, with particular emphasis on recording of antibiotic treatments. The 43 farmers interviewed belonged to veterinary health cooperatives. All farmers correctly named an antibiotic or antibiotic preparation, yet only 2 recognized the 5 components of the farm register. Farmer attitudes toward the register were globally positive, even though they named a wide variety of constraints. Nevertheless, 72% of farmers interviewed had a permanent health record, and approximately half had recorded either the last treatment (irrespective of drug class) or the last intramammary tube administered. Results were discussed in the light of health behavior change models that are applied in human medicine. We suggest that programs that seek compliance with the farm register should focus on educational interventions and bonus incentives.     

Continuous source outbreak of campylobacteriosis traced to chicken

Poultry is a source of human campylobacteriosis, but a large continuous source outbreak, heretofore, has not been attributed to both a single source of poultry and single serotype of Campylobacter. Here we report an outbreak of C. jejuni affecting 6 catering college trainees and 13 patrons of a restaurant in southern England. An epidemiological investigation successfully tracked the outbreak source to the farm of origin. Frequency of occurrence of campylobacters and outbreak serotype distribution were determined in index cases, the local population, and local chicken suppliers. The source farm was investigated and the effect of interventions assessed. A single outbreak serotype of C. jejuni was isolated from trainee chefs, patrons, and chicken supplied to the college by Wholesaler A. The Campylobacter isolation rate for Wholesaler A was 89% (98% outbreak serotype), compared to 40% for non-Wholesaler A (10% outbreak serotype). The isolation rate for 14 months averaged 85% (99% outbreak serotype) in chickens grown on two farms (X and Y) supplying Wholesaler A, contributing approximately 40% to all local cases. In the research reported here, a specific strain and hygiene practice were found to be important for understanding transmission of Campylobacter from poultry to humans in this outbreak.     

To change or not to change? Veterinarian and farmer perceptions of relational factors influencing the enactment of veterinary advice on dairy farms in the United Kingdom

Achieving herd health and welfare improvement increasingly relies on cattle veterinarians to train and advise farmers, placing veterinary interactions at the heart of knowledge exchange. Cattle veterinarians recognize their influence and the need to be proactive advisors but struggle with acting upon this awareness in daily practice, reporting a need to enhance their advisory approach to inspire farmer behavior change. Understanding how veterinarian-farmer interactions positively or negatively influence the enactment of change on farm is therefore essential to support the cattle veterinary profession. This paper adopts a qualitative approach to conceptualize how and under what circumstances veterinary advice has the potential to support and inspire farmer engagement with behavior change on the UK dairy farm. Fourteen UK dairy farms were recruited to take part in a qualitative study involving research observation of a typical advisory consultation between veterinarian and farmer (n = 14) followed by separate, in-depth interviews with the farmer(s) and their respective veterinarian. Interview data were organized using a template coding method and analyzed thematically. While accuracy of veterinary advisory content was valued, it was a relational context of trust, shared veterinarian-farmer understanding, and meaningful interpretation of advice at a local (farmer) level that was most likely to enact change. Critically, these relational factors were reported to work together synergistically; a trusting relationship was an essential, but not necessarily sufficient, component to create a culture of change. Findings suggest that cattle veterinarians may benefit from tailoring advisory services to the farmer's specific world view, facilitated by a shared understanding of the farmer's immediate and long-term motivational drivers. In consequence, cattle veterinarians seeking to positively engage farmers in advisory interactions could consider a focus on farmer priorities, motivations, and goals as paramount to frame and inform advisory messages. This explicit collaborative communication encourages the selection of appropriate and timely veterinary expertise, leading to better integration and adoption of advice on farm given enhanced advisory relevance for farmers' unique circumstances. This farmer-centered approach, involving active co-creation of plans between individuals, is critical for engagement and commitment when tackling complex problems.     

国内外蛋类兽药最大残留限量标准对比分析

对比了我国蛋类兽药最大残留限量与CAC、美国、日本、新加坡、加拿大的异同。从涉及的兽药种类、耙组织分类、残留限量值三个方面进行了对比。结果表明我国蛋类兽药最大残留限量与发达国家相比存在以下差距:涉及兽药种类少;耙组织规定比较单一;一些兽药的限量值不尽合理;风险评估研究不够。并提出了完善我国蛋类兽药残留限量标准的措施和建议。     

2016年云南省部分地区鸡蛋中兽药及禁用药物残留监测结果分析

目的 了解云南省部分地区鸡蛋中兽药及禁用药物残留水平, 为监督执法的提供技术支撑。方法 采集云南省昆明等部分地区超市、农贸市场销售的鸡蛋67份, 按照国家标准方法和《2016年国家食品污染和有害因素风险监测工作手册》对鸡蛋中氯霉素、五氯酚钠、金刚烷胺、利巴韦林、甲硝唑、喹诺酮类抗菌药11项、四环素类抗菌药4项残留检测, 检测结果依据2002年农业部235号公告《动物性食品中兽药最高残留限量》等进行评价。结果 氯霉素、金刚烷胺、五氯酚钠未检出, 利巴韦林检出率1.49(1/67), 甲硝唑检出率为32.84%(22/67), 四环素类检出率为37.31%(25/67), 喹诺酮类检出率为4.48%(3/67)。结论 云南省部分地区鸡蛋中甲硝唑残留情况较严重, 应该引起相关部门重视。     

Estimating the effect of mastitis on the profitability of Irish dairy farms

The objective of this paper was to estimate the effect of the costs of mastitis on the profitability of Irish dairy farms as indicated by various ranges of bulk milk somatic cell count (BMSCC). Data were collected from 4 sources and included milk production losses, cases treated, and on-farm practices around mastitis management. The Moorepark Dairy Systems Model, which simulates dairying systems inside the farm gate, was used to carry out the analysis. The cost components of mastitis that affect farm profitability and that were included in the model were milk losses, culling, diagnostic testing, treatment, veterinary attention, discarded milk, and penalties. Farms were grouped by 5 BMSCC thresholds of ≤ 100,000, 100,001-200,000, 200,001-300,000, 300,001-400,000, and > 400,000 cells/mL. The ≤ 100,000 cells/mL threshold was taken as the baseline and the other 4 thresholds were compared relative to this baseline. For a 40-ha farm, the analysis found that as BMSCC increased, milk receipts decreased from €148,843 at a BMSCC <100,000 cells/mL to €138,573 at a BMSCC > 400,000 cells/mL. In addition, as BMSCC increased, livestock receipts increased by 17%, from €43,304 at a BMSCC <100,000 cells/mL to €50,519 at a BMSCC > 400,000 cells/mL. This reflected the higher replacement rates as BMSCC increased and the associated cull cow value. Total farm receipts decreased from €192,147 at the baseline (< 100,000 cells/mL) to €189,091 at a BMSCC > 400,000 cells/mL. Total farm costs increased as BMSCC increased, reflecting treatment, veterinary, diagnostic testing, and replacement heifer costs. At the baseline, total farm costs were €161,085, increasing to €177,343 at a BMSCC > 400,000 cells/mL. Net farm profit decreased as BMSCC increased, from €31,252/yr at the baseline to €11,748/yr at a BMSCC > 400,000 cells/mL. This analysis highlights the impact that mastitis has on the profitability of Irish dairy farms. The analysis presented here can be used to develop a "cost of mastitis" tool for use on Irish dairy farms to motivate farmers to acknowledge the scale of the problem, realize the value of improving mastitis control, and implement effective mastitis control practices.     

超高效液相色谱-串联质谱法同时检测牛乳中4 种驱虫药物残留

建立同时检测牛乳中4 种驱虫药物（吡喹酮、伊维菌素、阿维菌素、多拉菌素）残留的超高效液相色谱-串联质谱的方法。样品经乙腈提取,碱性氧化铝固相萃取小柱净化,采用UPLC ACQUITY BEH C18柱,以0.1%甲酸-乙腈（A）和0.1%甲酸-5.0 mmol/L乙酸铵（B）为流动相,梯度洗脱分离,在电喷雾正离子模式下以多反应监测方式检测。结果表明：4 种驱虫药物在5～100 ng/mL范围内线性良好,相关系数大于0.996,加标样品的平均回收率为76.4%～113.3%,相对标准偏差（n=6）为2.4%～10.6%。吡喹酮、伊维菌素、阿维菌素、多拉菌素的检出限分别为1.0、2.5、2.5、2.5 μg/kg。该方法简便、快速、准确,可以同时检测牛乳中吡喹酮、伊维菌素、阿维菌素、多拉菌素残留。     

A longitudinal study of Salmonella and Campylobacter jejuni isolates from day of hatch through processing by automated ribotyping

Comparisons of bacterial populations over long periods of time allow researchers to identify clonal populations, perhaps those responsible for contamination of farms or humans. Salmonella and Campylobacter can cause human illness, and our objective was to use a library typing system to track strains that persist in the poultry house and through the processing plant. Two farms, over four consecutive flocks, were studied. Multiple samples were taken of the poultry house environment, feed mill, transport crates, and carcasses in the processing plant. Sample collection on the farm took place on chick placement day, midgrowout, and the day of harvest. This study found that 80.3% of isolates belonged to a single strain of Salmonella Kentucky that persisted in several environmental samples for all flocks at both farms, from chick placement day to the final product at the plant. Surgical shoe covers produced most isolates (n = 26), and processing day yielded the highest recovery (n = 68). Additional serotypes were recovered, but the Salmonella Kentucky-positive eggshells and chick mortality appeared to be the source of the organism for both farms. All Campylobacter isolates recovered were identified as C. jejuni. Most Campylobacter isolates (90.1%) belonged to one of three core strains. C. jejuni was not recovered on chick placement day. Cecal droppings yielded all nine strains. Most isolates (98.2%) were from one farm. Cluster analysis grouped C. jejuni and Salmonella isolates into four and six distinct clusters, respectively, on the basis of a similarity level of 80%.     

A survey of biosecurity and health management practices on Irish dairy farms engaged in contract-rearing

A survey was conducted to investigate potential differences in biosecurity and health management practices on Irish dairy farms that sent their heifers for contract-rearing (source dairy farms, SDF; n = 62) and those rearing their own heifers (control farms, CF; n = 50). Participating farmers were surveyed by postal questionnaire between September and November 2018. The overall response rate was 93%. Results show that structurally, SDF were larger, less fragmented, and more specialized than CF. Outsourcing of labor-intensive activities to external contractors was more common among SDF than CF, exposing them to potentially increased biosecurity risks associated with animal movements, use of shared equipment, and increased frequency of farm visitors. The majority of SDF sent heifers to a single-origin rearing facility (70%), with heifers most commonly arriving at the rearing unit between 2 and 4 mo (53%) and returning to the dairy farm between 18 and 21 mo of age (56%). Despite the increased biosecurity risk associated with contract-rearing, implementation of disease prevention measures was not superior on SDF compared with CF. For both farm types, there was scope for improvement to visitor biosecurity protocols, quarantine procedures, colostrum feeding practices, and hygiene of calving areas. This research provides an overview of the demographics and farm management practices implemented by dairy farmers engaged in contract-rearing of replacement heifers, and will serve to inform farmers, veterinary advisors, and policy makers.     

Associations between farmer participation in veterinary herd health management programs and farm performance

In the past few decades, farms have increased in size and the focus of management has changed from curative to preventive. To help farmers cope with these changes, veterinarians offer veterinary herd health management (VHHM) programs, whose major objective is to support the farmer in reaching his farm performance goals. The association between farm performance and participation in VHHM, however, remains unknown. The aim of this paper was to compare farm performance parameters between participants and nonparticipants in VHHM and to differentiate within participation to evaluate the possible added value of VHHM on the farm. Five thousand farmers received a questionnaire about the level of VHHM on their farm. Farm performance parameters of these 5,000 farms were provided. For all respondents (n = 1,013), farm performance was compared between participants and nonparticipants and within level of participation, using linear mixed and linear regression models. Farmers who participated in VHHM produced 336 kg of milk/cow per year more and their average milk somatic cell count (SCC) was 8,340 cells/mL lower than farmers who did not participate in VHHM. Participating herds, however, had an older age at first calving (+12 d), a lower 56-d nonreturn rate percentage (−3.34%), and a higher number of inseminations per cow (+0.09 inseminations). They also had more cows culled per year (+1.05%), and a lower age at culling (−70 d). Participants in the most-extended form of VHHM (level 3) had a lower SCC (−19,800 cells/mL), fewer cows with high SCC (−1.70%), fewer cows with new high SCC (−0.47%), a shorter calving interval (−6.01 d), and fewer inseminations per heifer (−0.07 inseminations) than participants in the least-extended form of VHHM (level 1). Level 3 participants, however, also had more cows culled per year (+1.74%) and a lower age at culling (−103 d). Discussing specific topics with the veterinarian (milk production, fertility, and udder health) had only marginal effects on improving the farm performance parameters related to those topics. Given the relevance of fertility on the farm and the focus on longevity by society, it is important to determine underlying reasons for the negative associations of these topics with participation in VHHM. A longitudinal study could provide answers to this. For now, veterinarians should be aware of the associations. The increased milk production and milk quality could help the marketing of VHHM to farmers.     

Occurrence and genotypes of Campylobacter in broiler flocks, other farm animals, and the environment during several rearing periods on selected poultry farms

On 15 Swiss poultry farms, broiler flocks, other farm animals, and the environment were examined during consecutive rearing periods to investigate the occurrence and genetic diversity of Campylobacter. Of the 5154 collected samples, 311 (6%) from 14 farms were Campylobacter positive by culture. Amongst the positive samples, 228 tested positive for Campylobacter jejuni and 92 for Campylobacter coli. Positive samples originated from broilers, the broiler houses, cattle, pigs, bantams, laying hens, a horse, and a mouse. Feed, litter, flies, and the supply air to the broiler house tested negative. By flagellin gene typing (fla-RFLP) and pulsed-field gel electrophoresis (PFGE), 917 Campylobacter isolates were genotyped. Additionally, amplified fragment length polymorphism (AFLP) analysis was performed on 15 assorted strains. On eight farms, matching genotypes were isolated from broiler flocks and other farm animals: Certain genotypes from cattle (farms H, K, L, and M), pigs (farms D and P), or laying hens (farm L) were subsequently found in the broiler flocks, whereas other genotypes initially present in the broiler flocks turned up in cattle (farms A, D, and O). These results emphasize the importance of other farm animals on poultry farms for broiler flock colonization. Indications of persistent contamination of the broiler house were evident on four farms (C, D, I, and L) where matching genotypes were detected in consecutive broiler flocks, but not concurrently in other samples. By fla-RFLP, PFGE, and confirmed by AFLP, some genotypes proofed to be identical across different farms.