Index Lists provided by the VAMPP computer programme for dairy herd health and production control. III. Interpretation and analysis of data on Index List 3

In a series of four papers computerized herd reports for dairy herd health and production control purposes, the Index Lists, are presented. This third paper deals with Index List 3 on youngstock rearing and cow culling. The information from this list is suitable for monitoring rearing efficiency and culling policy in a veterinary herd health and production control programme, especially when used in combination with information from the other index lists. Methods for interpretation and evaluation of the data are provided. It is demonstrated how prompt computerized analysis of current information is used to detect deviations in index figures and to advise the farmer.     

Index Lists provided by the VAMPP computer programme for dairy herd health and production control. IV. Interpretation and analysis of data on Index List 4

In a series of 4 papers computerized herd reports on various aspects of dairy farming, the Index Lists, are presented for herd health and production control purposes. This fourth paper regards Index List 4 on nutritional disorders, body condition and ration composition. The information from this list is suitable to monitor nutritional efficiency and feeding management, especially when used in combination with information from the other index lists. Methods for interpretation and evaluation of the data listed are provided. Evaluations should take into account the aspects related to nutrition. It is demonstrated how deviations of index figures are detected and how advice to farm management is built up by means of actual information and prompt computerized analysis.     

Index LISTS provided by the VAMPP computer programme for dairy herd health and production control

Summary

In a series of 4 papers computerized herd reports on various aspects of dairy farming, the Index Lists, are presented for herd health and production control purposes. This fourth paper regards Index List 4 on nutritional disorders, body condition and ration composition. The information from this list is suitable to monitor nutritional efficiency and feeding management, especially when used in combination with information from the other index lists.

Methods for interpretation and evaluation of the data listed are provided. Evaluations should take into account the aspects related to nutrition. It is demonstrated how deviations of index figures are detected and how advice to farm management is built up by means of actual information and prompt computerized analysis.     

Index Lists provided by the VAMPP computer programme for dairy herd health and production control. I. Interpretation and analysis of data on Index List 1

In a series of 4 papers the Index Lists as provided by the VAMPP computer programme are presented. The information on Index List 1, covering milk production, milk quality and udder health, is suitable to monitor actual herd performance, especially when used in connection with the other index lists. With computer programmes becoming available to veterinary control programmes, proper interpretation and prompt analysis of data is more critical. This paper outlines how deviations of index figures from reference values are detected, how analysis may be performed and how advice is built-up.     

Veterinary herd health and production control on dairy farms III. Index list on reproduction and lameless

In a previous paper an introduction was presented to a veterinary herd health and production control program consists of a coupled basic system and a flexible system. The basic system is built up from farm visit activities and a standard registration system. In the latter, four index lists play a key role. These index lists cover all relevant farm aspects with regard to the efficiency of milk production, calf production and cow replacement. Index figures are built up or calculated from data collected by both the farmer and the veterinarian. Their function is to signalize unwanted situations or problems at an early stage and to serve as basic information for analysis, solving and prevention of problems. Problem analysis is performed by means of the flexible system, which indicates to what extent actions are needed.After a previous paper concerning index list 1 on milk production and udder health, this paper presents index list 2 on reproduction and lamenes. Both farm aspects are related to the economic results achieved on the farm. The development, significance and implementation of the index figures in list 2 are presented. Relationships with figures in other index lists are discussed. Reference values are given where applicable.     

Heat stress in dairy cattle and other livestock under southern African conditions. III. Monthly temperature-humidity index mean values and their significance in the performance of dairy cattle

Temperature-humidity index (THI) values applicable to South Africa and Namibia have been established during this investigation for each month of the year by means of computerized modelling and mapping techniques. The data indicate that each year heat stress risk areas (HSRA's) expand from August to January and retract from February to July. The THI values classified according to the Livestock Weather Safety Index (LWSI) for lactating dairy cattle (LDC), suggest that, especially during November to March there is the risk of moderate to advanced heat stress in most South African dairy cows. This has important implications for their general health, udder health, production and reproduction. Careful planning of facilities and highly adaptable herd management are required to protect dairy cattle from heat stress.     

Working towards a reduction in cattle lameness: 1. Understanding barriers to lameness control on dairy farms

On 222 dairy farms, the farmer’s perception of the scale of the herd lameness problem was compared with the prevalence detected by observation of the milking herd, and a questionnaire explored the barriers to lameness reduction. Ninety percent of farmers did not perceive lameness to be a major problem on their farm, although the average prevalence of lameness was 36%. For 62% of the sample, lameness was not the top priority for efforts made to improve herd health. Time and labour were important limiting factors for lameness control activities and financial constraints prevented farmers taking action on advice in 30% of cases. Farmers’ understanding the implications of lameness for the farm business was limited. Lameness reduction is restricted by farmers’ perception of lameness, but also by time, labour and finance; these issues need to be addressed at the industry level to support animal welfare improvement.     

Lameness prevalence and risk factors in organic and non-organic dairy herds in the United Kingdom

This study aimed to compare the prevalence of lameness on organic and non-organic dairy farms in the United Kingdom (UK) and to assess which cow and farm factors influenced lameness levels. Forty organic and 40 non-organic dairy farms across the UK were repeatedly visited over a 2.5 year period. On each visit all milking cows were locomotion scored, and information about farm housing, management and husbandry practices was recorded on-farm. Over the whole study, the mean herd lameness prevalence was 16.2%, 16.3% and 19.3% in the autumn, winter and spring observation periods, respectively. Lameness prevalence was lower (P=0.012) on organic farms compared to non-organic farms. Numerous specific factors were found to significantly influence the prevalence of lameness. This study provided evidence that organic management reduced herd lameness. It supported previous research which suggested that lameness is a serious problem on many farms in the UK and further emphasised the multi-factorial aetiology of lameness problems.     

Veterinary herd health and production control on dairy farms II. Index list on milk production and udder health

In a previous paper an introduction was presented to a veterinary herd health and production control program. This program consists of a basic system and a flexible system. The basic system is built up from a standard on-farm and program registration system and from farm visit activities. In the registration system four index lists play a key role. These index lists comprise all relevant farm aspects with regard to the efficiency of milk production, calf production and cow replacement. Problem analysis is performed by means of the flexible system which indicates to what extent action for problem solving is needed.This paper presents index list 1 on milk production performance and udder health. Both aspects are of crucial importance to the economic results achieved on the farm. The index figures in list 1 serve to signalize unwanted situations or problems in relation to the aspects mentioned on the other lists. Index figures are built up from data collected on the farm by both the farmer and the veterinarian, and they serve as the basis for further analysis, solving and prevention of problems.The development, significance and implementation of the index figures in list 1 are presented. Reference values are given where applicable.     

The incidence, cost and factors associated with foot lameness in dairy cattle in south-western Victoria

A survey of 73 dairy farms in south-western Victoria was conducted to assess the cost and mean herd incidence of foot lameness for the period from calving to the end of November, 1985, and to identify the herd, management and environmental factors associated with foot lameness. The mean herd size was 125 cows (range 82 to 220). Lameness occurred in 64 (88%) herds, and the mean herd incidence was 7.0% (range 0.0 to 30.9%). The main clinical signs associated with lameness were the presence of overworn and/or bruised soles, or stones lodged in the interdigital cleft. Factors associated with lameness were: property and herd size, age of cow, bail feeding, voluntary entry into the bails, and features of the farm track including its length, the presence of steep slopes, the type of surface material, presence and treatment of broken sections and maintenance including rolling history. The association of these factors with specific clinical signs was examined. The mean cost was estimated to be $42.90 per lame cow due to loss of production, treatment, the culling or death of lame cows, and extra man hours spent managing lame cows. It was concluded that the site, construction, maintenance and use of the farm track were of major importance to the incidence of lameness in herds in this area and recommendations for reducing lameness are made.     

Behavioural characteristics of dairy cows with lameness in Taranaki, New Zealand

AIM: To investigate possible relationships between the incidence of lameness in dairy cows, and walking order from the paddock into the milking shed, milking order, and dominance structure in the herd. METHODS: Ten dairy herds from the Taranaki region in New Zealand, with an average herd size of 183 cows, were observed during early, mid and late lactation. Each observation period consisted of five observations within 1 week, totalling 15 observations per farm. Three observers recorded the daily movement of cows between paddocks and the milking shed at each of three different locations. Additionally, the dominance structure of 21 cows per herd, randomly selected at the beginning of the study, was determined at the beginning of each of the three observation periods, on the basis of antagonistic behaviour. RESULTS: Within herds, walking and milking order showed a Kappa value of 0.31, reflecting fair agreement beyond chance. Based on the multivariate model, an increased risk of lameness was found for cows that walked or were milked in the last quarter of the herd (OR=1.8 and 1.5, respectively) compared with animals that walked/were milked in the first three quarters of the herd. The dominance structure of the randomly selected animals remained stable during the course of the lactation. High dominance animals tended to walk at the front of the herd and get milked first, whereas low dominance animals tended to walk at the back of the herd and get milked last. Although lameness was not significantly related to the dominance group, this could have been due to the low power of the study. CONCLUSIONS: The results of the study suggested that there is a relationship between the position of the animal in the herd and the risk of lameness in dairy cows, but that the strength of this relationship varied between herds. CLINICAL RELEVANCE: Walking/milking order was a risk factor for conditions causing lameness in dairy cows, and for the effective management of herd lameness problems it is important for farmers to be aware of this relationship.     

Studies in the control of bowie in lambs

AIM: To investigate possible relationships between the incidence of lameness in dairy cows, and walking order from the paddock into the milking shed, milking order, and dominance structure in the herd.

METHODS: Ten dairy herds from the Taranaki region in New Zealand, with an average herd size of 183 cows, were observed during early, mid and late lactation. Each observation period consisted of five observations within 1 week, totalling 15 observations per farm. Three observers recorded the daily movement of cows between paddocks and the milking shed at each of three different locations. Additionally, the dominance structure of 21 cows per herd, randomly selected at the beginning of the study, was determined at the beginning of each of the three observation periods, on the basis of antagonistic behaviour.

RESULTS: Within herds, walking and milking order showed a Kappa value of 0.31, reflecting fair agreement beyond chance. Based on the multivariate model, an increased risk of lameness was found for cows that walked or were milked in the last quarter of the herd (OR=1.8 and 1.5, respectively) compared with animals that walked/were milked in the first three quarters of the herd. The dominance structure of the randomly selected animals remained stable during the course of the lactation. High dominance animals tended to walk at the front of the herd and get milked first, whereas low dominance animals tended to walk at the back of the herd and get milked last. Although lameness was not significantly related to the dominance group, this could have been due to the low power of the study.

CONCLUSIONS: The results of the study suggested that there is a relationship between the position of the animal in the herd and the risk of lameness in dairy cows, but that the strength of this relationship varied between herds.

CLINICAL RELEVANCE: Walking/milking order was a risk factor for conditions causing lameness in dairy cows, and for the effective management of herd lameness problems it is important for farmers to be aware of this relationship.     

Investigating herds with lameness problems.

Many dairy herds have unusual or exceptionally serious lameness problems. Based on published observations of risk factors for specific disease problems, along with the author's experience, this article describes a systematic way to approach and evaluate lameness problems. It is important to define the etiologic diagnosis because preventive or corrective measures depend on the cause of the herd problem. Compound etiologies and complex risk factor interactions are the norm in this sometimes frustrating endeavor.     

Prevention and control of lameness in dairy cattle

The prevention and control of lameness are essential if a dairy herd is to return a profit. Breeding, feeding, housing, and management practices are all involved, and errors or omissions in any of these areas can result in catastrophic lameness. An accurate diagnosis and proper treatment are necessary to minimize losses when lameness occurs.     

A case study of lameness in three dairy herds

All cases of lameness that occurred in cows from three dairy herds between August 198'3 and July 1990 were examined every 2 weeks from the onset of lameness until the lesions resolved. The incidences of herd lameness were 38%, 22% and 2%. Some 186 clinical lesions were identified in 134 cases of lameness in 120 cows. Sole bruising (42%) and white line separation (39%) were the most frequently diagnosed conditions. Lateral digits of the hind limbs were the most affected. The mean time from the onset of lameness to clinical recovery was 27 days and to lesion recovery was 35 days. The peak incidence of lameness occurred during winter for autumn-calving cows and during the late spring for spring-calving cows. The onset of lameness was associated with the stage of lactation and wet weather conditions. Survival analysis revealed that the probability of an individual cow lasting in the milking herd for any specified period of time without becoming lame was highly associated with both her herd environment and her age. Total lactation yields of milk, milk fat and milk protein were lower for cows suffering from lameness than for herd-mates matched on age and proximity on calving date (P<0.05). Reproductive performance was also poorer in lame cows than in their herd-mates.     

A case study of lameness in three dairy herds

All cases of lameness that occurred in cows from three dairy herds between August 1989 and July 1990 were examined every 2 weeks from the onset of lameness until the lesions resolved. The incidences of herd lameness were 38%, 22% and 2%. Some 186 clinical lesions were identified in 134 cases of lameness in 120 cows. Sole bruising (42%) and white line separation (39%) were the most frequently diagnosed conditions. Lateral digits of the hind limbs were the most affected. The mean time from the onset of lameness to clinical recovery was 27 days and to lesion recovery was 35 days. The peak incidence of lameness occurred during winter for autumn-calving cows and during the late spring for spring-calving cows. The onset of lameness was associated with the stage of lactation and wet weather conditions. Survival analysis revealed that the probability of an individual cow lasting in the milking herd for any specified period of time without becoming lame was highly associated with both her herd environment and her age. Total lactation yields of milk, milk fat and milk protein were lower for cows suffering from lameness than for herd-mates matched on age and proximity of calving date (p<0.05). Reproductive performance was also poorer in lame cows than in their herd-mates.     

The effects of liveweight loss and milk production on the risk of lameness in a seasonally calving,pasture fed dairy herd in New Zealand

Dairy herd managers have attempted to increase and maintain profits by selectively breeding dairy cattle for high production. Selection for milk production may have resulted in a tendency for greater liveweight (LW) loss postpartum. This study aimed to: (1) determine if excessive LW loss and milk yield in the first 50 days in milk (DIM) was associated with the development of lameness after 50 DIM, and (2) estimate the incidence risk of lameness in this herd attributable to excessive liveweight loss. The dataset comprised details from 564 mixed age cows from a single, seasonally calving, pasture fed dairy herd in New Zealand.     

Effects of conformation and management system on hoof and leg diseases and lameness in dairy cows.

Foot and leg disorders that result in lameness tend to increase with more confined management systems and increased production. Many factors affect hoof health, including genetics, conformation, diet, contagious agents, hygiene, housing systems, animal behavior, and management. This article describes relationships between hoof health and some of these factors as well as methods for prevention of lameness on a herd basis.     

Veterinary herd health and production service on dairy farms IV. Index list on calf rearing and cow culling

The Herd Health and Production Service program for use in veterinary dairy practice is comprised of a basic and a flexible system. The basic system is a uniform system of data recording, standard veterinary activities and problem detection. In problem detection 4 index lists play a key role. The 4 comprise of the parameters or index figures that are relevant in monitoring the efficiency of milk production, calf rearing and cow replacement. Data on milk production, health status and reproduction of both individual animals and the herd are collected by the farmer and the veterinarian and transformed into index figures.This paper introduces index list “3”, with index figures for the monitoring of calf rearing and cow culling as parts of a herd health program. The development, implementation and significance of the index figures are presented. The index figures serve to detect unsatisfactory farm situations or problems in calf rearing and in cow culling. They trigger further investigation and aid the solution to and prevention of problems. Relationships with farm parameters mentioned in other index lists are also considered. Objectives and reference values where applicable are provided.     

Prevalence of lameness and of associated claw disorders in Greek dairy cattle industry

The aim of this study was to assess the prevalence of lameness as well as the prevalence of claw–horn disruptions, abnormal claw shape and dermatitis in lame cows in Greek dairy farms and to evaluate their risk factors. Forty dairy farms were visited twice, during winter and during summer, and the lameness of milking cows was scored using a 5-point scale. In total 760 cows were lame (lameness score ≥ 3) and were further examined to identify macroscopically the claw disorders. The herd size, the trimming and footbathing frequency, the floor surface, the cleanness of the herd, the scraping frequency and the disinfectant used in the footbaths were recorded. The mean lameness prevalence was 18.7% and that of claw disorders observed in the lame cows was 75.4% for abnormal claw shape, 30.2% for dermatitis and 30.6% for claw–horn disruptions. Large herd size and the absence or only once per year trimming were associated with increased risk for the presence of lameness.