Imbedding HACCP principles in dairy herd health and production management: case report on calf rearing

Driven by consumer demands, European legislation has suggested the use of HACCP (Hazard Analysis Critical Control Point) as the quality risk management programme for the whole dairy chain. Until now, an exception has been made for primary producers, but as regulations evolve, on-farm HACCP-like programmes should be ready to assure food safety as well as animal health and animal welfare. In our field experiment, the HACCP-concept was used to combine both optimal farm management and formalisation of quality assurance in an on-farm situation in the Netherlands. The process of young stock rearing was chosen, since its importance for the future of the farm is often underestimated. Hazards and their associated risk factors can be controlled within the farm-specific standards and tolerances, as targets can be controlled by corrective measures and by implementation of farm-specific worksheets. The veterinarian is pivotal for the facility-based HACCP team, since he/she has knowledge about on-farm risk assessment and relations between clinical pathology, feed and farm management. The HACCP concept in combination with veterinary herd health and production management programmes offers a promising approach to optimise on-farm production processes (i.e., young stock rearing) in addition to a structural approach for quality risk management on dairy farms.     

A three year herd health and management program on thirty Dutch dairy farms

Summary

A herd health and management program was carried out from May 1974 to May 1977 on thirty Dutch dairy farms which did not have specific herd or management problems. The number of cows per farm varied between 40 and 160. There was a control group of thirty‐one comparable farms. The farms were visited every six weeks by the veterinarian of the Animal Health Service Institute, the local agricultural adviser of the NAAS and the local veterinarian.

The aim of the program was a whole farm approach. The program had a mainly advisory character and it was up to the farmer to follow the advice given, which was based on the theoretically optimal solution but adjusted to the farm situation. The basis of the administration of herd health was the Herd Fertility Chart. Farm inspection was by detailed observation. The program was primarily practical, and could be carried out by a well‐trained local veterinarian.

The data of the first (preparatory) year were compared with the results of the following two years.

The improvement in income feedcosts margin on the program farms exceeded that on control farms by Dfl. 176 per cow (therefore Dfl. 460 per ha. and Dfl. 12,535 per man). Factor Analysis showed that the herd health and management program influenced especially data concerning fertility. However this did not affect the income feedcosts margin per cow. The program also had an important influence on culling due to health problems and on feedcosts per cow, both of which considerably affected the income feedcosts margin per man. The results obtained may be considered to be minimal and might be higher on farms with herd health and management problems. The expenses involved in a program similar to that described, would appear to be a good choice of investment for farmers.     

The perception of veterinary herd health management by Dutch dairy farmers and its current status in the Netherlands: a survey

The importance of veterinary herd health management (VHHM) is increasing in both dairy farming and veterinary practice. Little is known, however, about how VHHM is perceived by farmers in terms of structure, content and satisfaction. In 2007 a questionnaire, containing questions about these three items was therefore sent to 800 Dutch dairy farmers. Farmers received two questionnaires, one for participants in VHHM and one for non-participants, allowing them to choose the appropriate one. Results were summarized and statistically analyzed. Farmers who were participating in VHHM had better farm performance. They were satisfied with the way VHHM was executed on their farm. However, there were some pressure points. Goal setting and evaluation was still not a regular part of VHHM, even though it is said to be effective in literature. Time spent on VHHM not visible to the farmer was often not charged or not clearly specified on the bill. The differences in opinions between participants and non-participants of VHHM indicated a lack of communication and/or product differentiation. Satisfaction with the way VHHM was executed on the farm had no significant influence on 305-day production. There was, however, some influence on calving interval and bulk milk somatic cell count (BMSCC).     

Random within-herd variation in financial performance and time to financial steady-state following management changes in dairy herd

Abstract

The manager of a dairy herd and the affiliated consultants constantly need to judge whether financial performance of the production system is satisfactory and whether financial performance relates to real (systematic) effects of changes in management. This is no easy task because the dairy herd is a very complex system. Thus, it is difficult to obtain empirical data that allows a valid estimation of the random (within-herd) variation in financial performance corrected for management changes. Thus, simulation seems to be the only option. This study suggests that much caution must be recommended when claming effect of changes in herd management because the link between management changes (cause) and effect (measured as improvement of gross margin per cow year) is extensively blurred by a large within-herd variation in available real life accounting data and differences between herds in time to steady state following management changes.     

A three year herd health and management program on thirty Dutch dairy farms. IV. Special aspects

The ultimate objective of a herd health and management program must be optimal farm net profit. Maximal profit can be expected by carrying out a program based on a whole farm approach. A simple and well-ordered registration system is one of the most important aspects for the success of a program. Experiences with the different registration systems of the program are discussed. In the future it is desirable to process the registered data by computer. The farmer should know the possibilities of the program in advance and must be motivated to carry out advice. When giving advice veterinarians have to take into account the specific circumstances on each farm and the objectives of the farmer. The veterinarian also has to be well-informed about the factors which influence the farm net profit and to this end cooperation with other experts is necessary. In this trial close cooperation between the veterinarian and agricultural adviser were seen as a very positive feature of the program. The program must be carried out at regular times in a fixed sequence, which covers complete herd health and farm management. The frequency of farm visits depends on the problems, farm size and the season. On average one visit per month will be sufficient for farms up to 100 dairy cows. Cooperation between farmer and veterinarian is one of the essential aspects. Frequent evaluation is very stimulating. The benefits of a herd health and management program were found to be substantial in this trial. Therefore the costs of the program can be considered by the farmer to be a sound investment.     

A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.

     

The potential use of cell count linear scores in veterinary herd health and production control on dairy farms. A preliminary report

Subclinical mastitis is a major problem in udder health control. Reduction of this infection is hard to achieve because subclinical mastitis is not obvious to the farmer. This study examined the value to the farmer of regularly supplying somatic cell counts from individual cows for the control of subclinical mastitis. The use of linear scores, i.e. logarithmic transformations of cell counts, appeared to be appropriate when combined with other relevant information on udder health and included in a herd health computer programme.     

A three year herd health and management program on thirty Dutch dairy farms. III. Economic evaluation of fertility control

Fertility control was part of a herd health and management program on thirty dairy farms in the province of Overijssel. A comparable control group of thirty-one farms was available. After two years of application of the program the improvement in income feedcosts margin per cow on the program farms exceeded that on control farms by Dfl. 176. Within the large variation in income between the farms it was not possible to accurately distinguish the effects of the different aspects of the program, despite the use of detailed techniques such as Factor Analysis: thus another approach to determine the income effect of fertility control was necessary. The total loss per farm due to sub-optimal fertility was determined, using calving interval data, forced replacement data and norm-loss rates. From computation of this loss on program and control farms, the income effect of fertility control was deduced. Excluding the cost of the program, a significant (P less than 0.01) positive effect of fertility control on the total calculated loss due to sub-optimal fertility was determined (average Dfl. 25.50 per cow, or about Dfl. 1,700 per farm, after two years of program application). This income effect differed considerably between farms with an initial good or poor situation regarding fertility. The program contributed more to the improvement of insufficient or moderate fertility than to the prevention of a deterioration in herds with excellent fertility, although on the latter farms the total program had a considerable positive effect.     

A three year herd health and management program on thirty Dutch dairy farms. I. Objectives, methods and main results

A herd health and management program was carried out from May 1974 to May 1977 on thirty Dutch dairy farms which did not have specific herd or management problems. The number of cows per farm varied between 40 and 160. There was a control group of thirty-one comparable farms. The farms were visited every six weeks by the veterinarian of the Animal Health Service Institute, the local agricultural adviser of the NAAS and the local veterinarian. The aim of the program was a whole farm approach. The program had a mainly advisory character and it was up to the farmer to follow the advice given, which was based on the theoretically optimal solution but adjusted to the farm situation. The basis of the administration of herd health was the Herd Fertility Chart. Farm inspection was by detailed observation. The program was primarily practical, and could be carried out by a well-trained local veterinarian. The data of the first (preparatory) year were compared with the results of the following two years. The improvement in income feedcosts margin on the program farms exceeded that on control farms by Dfl. 176 per cow (therefore Dfl. 460 per ha. and Dfl. 12,535 per man). Factor Analysis showed that the herd health and management program influenced especially data concerning fertility. However this did not affect the income feedcosts margin per cow. The program also had an important influence on culling due to health problems and on feedcosts per cow, both of which considerably affected the income feedcosts margin per man.(ABSTRACT TRUNCATED AT 250 WORDS)     

Measuring the impact of different veterinary service programs on dairy herd health and milk production

This paper presents estimates of the relative impacts on reproductive status, the incidence of mastitis, and milk production of different types of veterinary service programs. The effects of veterinary services, categorized as emergency, scheduled and mixed, were modeled as a recursive system in which services affect herd health and health affects milk output. Veterinary services also affect milk output directly. Estimates are based on a small sample of dairies from the Tulare milkshed of California, and attention is concentrated on obtaining accurate data and addressing conceptual problems in modeling the effects of veterinary services.The data were pooled over dairies and months. Multiple regression was used to estimate production or yield functions for measures of herd reproductive health, under health, and milk. The data were corrected for autocorrelation and heteroskedasticity in the regression residuals. Student's t-statistic was used for test of significance. The estimated yield equations were used to calculate changes in health and milk output from changes in veterinary services.Currently available measures of herd reproductive status may not be valid for measuring reproductive health, because they confound management decisions with health status. Available data on udder health are satisfactory. The relative effects of different veterinary service programs were found to differ according to the aspects of herd performance being examined, and it may be important to account for indirect effects of scheduled services that are manifested through management.     

A three year herd health and management program on thirty Dutch dairy farms. II. Culling strategy and losses caused by forced replacement of dairy cows

Cows are culled at a relatively low age, which causes considerable economic loss. The annual culling rate in the Netherlands has increased from 18.8 per cent in 1951 to 25-30 per cent of the average number of cows in more recent years. The productive life is now about 3.5 years. On the thirty farms of the program group and thirty-one farms of the control group, the main reasons for culling were reproductive failure followed by mastitis and teat injuries. About 60 per cent of culling was due to health problems, the other 40 per cent to low productive capacity, old age, poor workability etc. The annual culling rate varied per farm per year but also per month. The moment of culling in the current lactation, the slaughter value and the age differed per reason. The calculated loss of forced replacement consists of reduction in both production prior to culling and slaughter value. Additionally, there is an idle production period due to lack of an immediate replacement. The biggest loss is caused by lost future income. There was a considerable difference per farm in the loss caused by culling for health problems. A low culling rate due to health problems was associated with longer longevity and a relatively lower loss. Tangible effects due to changes in the farm culling policy may not be evident for some years. The reduction in loss of culling in the program farms compared with the controls was small because the duration (2 1/2 years) of the herd health and management program was too short.(ABSTRACT TRUNCATED AT 250 WORDS)     

A mixed methods inquiry: How dairy farmers perceive the value(s) of their involvement in an intensive dairy herd health management program

Background

Research has been scarce when it comes to the motivational and behavioral sides of farmers'' expectations related to dairy herd health management programs. The objectives of this study were to explore farmers'' expectations related to participation in a health management program by: 1) identifying important ambitions, goals and subjective well-being among farmers, 2) submitting those data to a quantitative analysis thereby characterizing perspective(s) of value added by health management programs among farmers; and 3) to characterize perceptions of farmers'' goals among veterinarians.

Methods

The subject was initially explored by means of literature, interviews and discussions with farmers, herd health management consultants and researchers to provide an understanding (a concourse) of the research entity. The concourse was then broken down into 46 statements. Sixteen Danish dairy farmers and 18 veterinarians associated with one large nationwide veterinary practice were asked to rank the 46 statements that defined the concourse. Next, a principal component analysis was applied to identify correlated statements and thus families of perspectives between respondents. Q-methodology was utilized to represent each of the statements by one row and each respondent by one column in the matrix. A subset of the farmers participated in a series of semi-structured interviews to face validate the concourse and to discuss subjects like animal welfare, veterinarians'' competences as experienced by the farmers and time constraints in the farmers'' everyday life.

Results

Farmers'' views could be described by four families of perspectives: Teamwork, Animal welfare, Knowledge dissemination, and Production. Veterinarians believed that farmers'' primary focus was on production and profit, however, farmers'' valued teamwork and animal welfare more.

Conclusion

The veterinarians in this study appear to focus too much on financial performance and increased production when compared to most of the participating farmers'' expectations. On the other hand veterinarians did not focus enough on the major products, which farmers really wanted to buy, i.e. teamwork and animal welfare. Consequently, disciplines like sociology, economics and marketing may offer new methodological approaches to veterinarians as these disciplines have understood that accounting for individual differences is central to motivate change, i.e. ''know thy customer''.     

Evolution of farm management, nitrogen efficiency and economic performance on Dutch dairy farms reducing external inputs

The implementation of the statutory Mineral Accounting System (MINAS) in the Netherlands in the period 1998–2003 required large reductions in nutrient inputs of dairy farms. Patterns in farm management adjustments throughout 6 years and their effectiveness in terms of nitrogen use efficiency (NUE) and economic performance were evaluated for 45 commercial farms participating in a regional nutrient management project.

Six groups of farms were identified that differed in initial NUE and the change therein. Three groups of farms that were able to rapidly reduce fertilizer N input and establish a consistent farm management strategy were most successful in improving NUE. These farms had a higher gross margin per 100 kg milk than farms without a consistent strategy. The three effective strategies were primarily characterized by (i) continuous, gradual adjustment of the integrated farm management combined with a slight reduction in milk production per ha (re-balancing) versus increasing productivity per animal, thereby reducing maintenance N requirements, while (ii) maintaining or (iii) increasing the production intensity per ha. It was concluded that different approaches to improve NUE can be successful, also in economic terms, although a direct relationship between NUE and gross margin was not observed. The probably implicit choice for adoption of a strategy may be governed by farm endowment and the farmer's skills and objectives.     

The effects of lameness on reproductive performance, milk production and culling in Dutch dairy farms

A retrospective cohort study design was used to investigate the effect of lameness on reproductive performance on 13 commercial Dutch dairy farms. The data were collected during a routine herd health and production control program.

The cumulative 100-DIM (days in milkl) production in the previous lactation of lame cows was higher and the culling rate lower than that of the controls. The 100- and 270-DIM production of the cows with a sole ulcer was higher than that of the control cows. There was no difference in 100- and 270-DIM production between cows with a lameness diagnosis other than sole ulcer and the controls.

Lameness prolonged the interval from calving to first service and the interval from first service to conception. The pregnancy rate at first service was not affected by lameness.     

奶牛酮病发病原因及其对生产性能影响调查分析

探索奶牛酮病发病原因、发病规律及其对生产性能的影响,对986头围产期奶牛进行跟踪调查分析。结果表明,奶牛酮病发病率为31.74%,死亡率为4.15%;秋季发病率最高,可达37.4%,其次是冬季和夏季,春季发病率最低;随着胎次、年龄和产乳量的增加,奶牛酮病的发病率明显增高;在第1个泌乳月奶牛酮病的发病率最高,可达50.43%;日粮种类和微量元素越少,奶牛酮病就越容易发生;奶牛发病后受胎率明显降低;发病后产乳量、乳脂率、乳蛋白率、乳糖率和乳干物质比发病前均明显降低,差异显著（P〈0.05）。奶牛酮病发病具有一定的规律性,且可降低奶牛的繁殖性能、产奶量和乳品质。     

The impact of installation of automatic milking system on production and reproduction traits of dairy cows

The objective of the research was the evaluation of change in the traditional milking system using automatic milking system in the scope of the selected reproduction features of dairy cows of the Polish Holstein–Friesian breed. Animal material consisted of 2,818 cows used on nine farms equipped with the automatic milking system Astronaut A4 made by Lely. The cows were controlled in the scope of services per conception, service period, length of pregnancy, calving interval and calving to conception period, milk yield, protein and fat content obtained in lactations of 305 days. The selected traits were observed between 2005 and 2015. In this period, the milking system was changed from the conventional to automated one. The collected data material was statistically processed, using the multifactorial analysis of variance. The period between the first calving and the second effective insemination was reduced by 11.8 days, and the period between the second calving and the third effective insemination was shortened by 4 days after the installation of the automatic milking system. The increase in milk yield by 466 kg during 305‐day lactation was observed among primiparous cows. The percentage of protein and fat content in the researched groups decreased; moreover, the fall of intergroup variability was noticeable, which may be a sign of the levelling of the yield within the herd.     

Facial eczema management protocols used on dairy farms in the North Island of New Zealand and associated concentrations of zinc in serum

AIMS: To describe and evaluate the current practices used to manage and prevent facial eczema (FE) in North Island dairy herds, and determine the within-herd prevalence of cows with elevated activities of gamma glutamyl transferase (GGT), and with concentrations of Zn in serum <18?μmol/L.

METHODS: Between January and May 2014, 105 herd managers from throughout the North Island of New Zealand were invited to participate in the study when regional spore counts for Pithomyces chartarum started to rise towards 30,000 spores/g pasture. Managers selected 10 representative cattle that were weighed and blood-sampled by the herd veterinarian. Blood samples were analysed for concentrations of Zn in serum and GGT activity. Pasture samples were also collected and submitted for spore count estimation. Finally a survey of farm management practices relating to prevention of FE was completed by the herd manager. A mixed-effects logistic regression model was used to determine associations between herd-level and cow-level explanatory variables and the probability of a cow having a concentration of Zn in serum <18?µmol/L.

RESULTS: Of the 1,071 cows tested, 79 (7.3 (95% CI=5.8–9.0)%) had GGT activity in serum >300?IU/L, and 35/106 (33 (95% CI=24.2–42.8)%) herds had ≥1 of the 10 cows sampled with GGT activity >300?IU/L. Of the 911 cows that were being treated with Zn, concentrations of Zn were between 18–35?μmol/L in 398 (43.6 (95% CI=40.4–46.9)%) cows, were >35?μmol/L in 32 (3.5 (95% CI=2.4–4.1)%) cows, and <18?μmol/L in 479 (52.6 (95% CI=49.3–55.9)%) cows. After adjusting for the confounding effect of region, the odds of a cow having concentrations of Zn in serum <18?μmol/L were 5.5 (95% CI=1.1–29) times greater for cows supplemented with zinc in water compared with those supplemented by drenching. Of the 105 herd managers, 103 (98%) stated that they had access to regional spore count data, but only 35/105 (33%) reported that they measured spore counts on their own farm. Overall, 98/105 (93%) managers reported that they had some form of FE management programme in place. Fungicides were used on their own or in combination with zinc treatments in 10 herds, ZnSO₄ in water troughs was used in 68 herds, oral drenching with ZnO in nine herds, and ZnO supplied in-feed in 26 herds. Estimated daily dose rates of zinc were less than that required to treat a 400?kg cow on 42/68 farms that administered ZnSO₄ in the water or ZnO as a drench.

CONCLUSION AND CLINICAL RELEVANCE: This study has shown that FE management on dairy farms in the North Island of New Zealand could be substantially improved. It is likely that improved FE management would occur if herd managers were provided with more feedback on the success (or otherwise) of their FE management programmes.     

Calf and colostrum management practices on New Zealand dairy farms and their associations with concentrations of total protein in calf serum

AIMS: To gather information on management practices and farmer attitudes to management of cows and calves during the immediate post-partum period on dairy farms in New Zealand, and to assess these practices for associations with concentrations of total protein (TP) in serum of calves 1–8 days-old.

METHOD: Between July and September 2015 blood samples were collected from calves aged between 24 hours and 7 days, from dairy farms (n=105) in nine areas in New Zealand, on three occasions throughout the calving period. Concentrations of TP were determined in all serum samples. At each visit technicians collected 1?L of the pooled colostrum that was intended for feeding to newborn calves that day. These samples were assessed for Brix, coliform and total bacterial counts. After the last sampling visit, the calf rearer or farm manager were asked to complete a questionnaire describing calf and colostrum management practices on the farm. Potential farm-level variables associated with concentrations of TP in serum of sampled calves were identified using univariable and multivariable linear mixed models.

RESULTS: Mean concentration of TP in serum of calves across all farms was 59.8 (95% CI=59.4–60.2) g/L, and was associated with region and herd size in the final multivariable model. Concentrations of TP were lower in calves from farms in Otago (56.2 (95% CI=53.4–58.9) g/L) and Southland (56.9 (95% CI=54.1–59.7) g/L) compared to calves on farms in the Far North (62.6 (95% CI=59.8–65.3) g/L), and were lower in calves from farms with a herd size >600 (58.3 (95% CI=56.7–59.8) g/L) than ≤600 (61.3 (95% CI=60.1–62.5) g/L) cows. After accounting for fixed effects, farm accounted for only 8.4% of the unexplained variation. There was no association between any of the measures of colostrum quality and concentrations of TP in serum (p>0.2).

CONCLUSION AND CLINICAL RELEVANCE: Very few herd-level variables were associated with concentrations of TP in serum. Risk factors that have been shown to be of importance in previous studies outside New Zealand were not identified as important in the current study. It is possible that, in the situation where calves are kept at pasture with their dams for prolonged periods, variables which influence how well a cow can feed its calf in the first 12–24 hours have a larger influence on concentrations of TP in serum than the collection and management of calves once they reach the rearing shed.     

VAMPP: a veterinary automated management and production control programme for dairy farms (the application of MUMPS for data processing)

The application of MUMPS in a computerised recording system for herd health and production control on dairy farms is reviewed. MUMPS is an interactive multi-user database management system, which is both an operating system and a high level computer language. In this system, coding of veterinary and management events prior to data entry is not needed. Programmes and data structure can easily be adapted and extended due to the features of MUMPS. The system for dairy farms allows epidemiological analyses, due to the flexibility of the programme. The programme is used by farmers and veterinary surgeons by means of terminals linked to a central computer. The system provides action lists for farmers and veterinary surgeons; the information on these lists is presented in a multidisciplinary way. Several herd reports and analyses, including frequency distributions and graphs, are given. These reports enable the investigation of cross-relations between farm aspects, and aid in the detection of problem areas.