SAC Research

Animal Health Projects

The environmental consequences of using home-grown legumes as a protein source in pig diets

The overall aim of this proposal is to investigate the potential of using home grown legumes, such as peas and beans, in the diets of growing/finishing pigs in order to reduce the environmental burdens associated with their production. Emphasis will be placed on the consequences of legume inclusion on environmental burden (nutrient excretion and its influence on diffuse pollution from pig operations) but also on pig performance. Furthering knowledge and understanding of the nutritional value of homegrown vegetable proteins is of considerable importance and would also lead to further interest in the cultivation of new cultivars by plant breeders.

Centre of Excellence Management

Management of Centre of Excellence (Secretariat)

Innovative and practical breeding tools for improved dairy products from more robust dairy cattle

The objective of ROBUSTMILK is to develop new practical technologies to allow breeders to refocus their selection to include milk quality and dairy cow robustness and to evaluate the consequences of selection for these traits taking cognisance of various milk production systems.

Modelling consequences of selection strategies on animal performance and health

Using porcine reproductive and respiratory virus syndrome infection as example, a bio-mathematical simulation model will be developed that: (1) quantifies the genetic potential for growth, and effective immune response in pigs, (2) describes the non-linear interactions between genotype, nutritional environment and environmental stressors (physical, social and infectious) in growth and immune processes, (3) predicts performance and health state for pig populations in various environments, (4) predicts short- and long-term consequences of selection for performance or disease resistance on performance and on health in environments of different infection pressures, and (5) provides guidelines for breeders on designing more effective selection strategies.

Genetic regulation and genomic selection of energy balance traits in dairy cattle

This SGRERAD Development-funded project supports a collaboration with Iowa State university, USA, which is funded from a USDA grant. The project aims to develop genetic selection strategies to improve the lifetime productivity, efficiency and welfare of dairy cows. Declining performance in production traits, for example reproduction, health and longevity, has become a major concern of the dairy industry worldwide. Energy balance (the difference between energy intake and energy expenditure) is of prime importance as it links production and non-production traits, through a common pool of available energy. Energy balance is not included in current breeding programmes as it is difficult to meaure. The overall aim of this project is to define the genetic regulation of energy balance at quanitative and molecular levels, and to incorporate energy balance into selection programmes. The way this will be done will be first to estimate genetic parameters for energy balance and define relationships among energy balance, production and fertility traits. We will then identify quantitative trait loci influening energy balance and related traits. Finally we will apply genomic selection methods to estimate energy balnce breeding values from marker genotypes. The results from this project should have application to the dairy industry, as they will enable selection for non-production traits.

Optimise breeding programmes for the UK sheep industry by the inclusion of genotype and environmental interaction

Objective 1: Review the literature on the importance of GxE on genetic gain in model and farm animal species e.g. sheep Objective 2: Review the literature on the genetic basis of environmental variance (genetic robustness) in model and farm animal species e.g. sheep Objective 3: Develop a classification system for environments in the UK sheep industry Objective 4: Investigate the extent of GxE in sheep using existing data from experimental and commercial flocks. Examine level of GxE in cross breeds. Examine the use of reaction norm methods to model GxE in addition to random regression models for body weight traits Objective 5: Estimate GxE for performance (e.g. growth, carcass composition) and efficiency traits (e.g. litter size reared, faecal egg count) in industry breeding programmes Objective 6: Develop strategies to accommodate possible GxE interactions in breeding programmes to both improve genetic robustness as well as selection of sires for specific environments and/or management systems.

Expanding Indices - The effect of a difficult calving on the subsequent health and welfare of the dairy cow and calf

The aim of this project is to investigate the short- and long-term effects of difficult calvings on subsequent health, welfare and behaviour of both the calf and the cow. Difficult births have a range of well documented short-term effects on survival and viability in calves, and on disease susceptibility and production in the cow. The UK dairy industry proposes to reduce the prevalence of difficult calvings by implementing a grading system for all calvings. Calvings would then be graded from ‘easy’ through to ‘difficult’. The aim of this project is to determine how calvings at each grade affects the health and welfare of the cow and calf in the short- and long-term. Short-tem effects will be assessed by making detailed measures of injury and behaviour in the peri-natal period. Long-terms effects will be investigated by assessing disease susceptibility, viability and behaviour.

Expanding Indices - Genetic analysis of selected fitness traits in UK dairy cattle

This project aims to providr cattle breeders with information to use in selection decisions that will help to improve cow welfare, health and sustainability. The necessary indices and methods will be developed, tested and implemented in order to achieve this end. This project is designed to achieve this objective by delivering breeding values and redesigned indices to the industry for udder health, calving difficulty and longevity.

Breeding for improved welfare, health and sustainability by expanding the selection objectives in dairy herds

1: Purebreeding - providing cattle breeders with information to use in selection decisions Improving cow welfare, health and sustainability through selective breeding is likely to have a lasting benefit to the UK industry. The necessary indices and methods will be developed, tested and implemented in order to achieve this end. This project is designed to achieve this objective by delivering breeding values and redesigned indices to the industry for udder health, calving difficulty and longevity. 2: Resolving some crossbreeding issues Improvement in health traits in crossbred animals is also a key outcome of this project. Direct measurements on cows and calves and the evaluation of breeding values for these health traits in the beef context will be made. The cow/calf measurements will be used to model the interplay between cow and calf with respect to the key aspects of calving difficulty. This model will be used to advise farmers on aspects of size and dimensions of both cow and calf in relation to calving difficulty. 3: More detailed investigation of the new traits The welfare effects of these three traits are not completely understood. Neither are the long-term effects of calving difficulty and poor udder health. Detailed studies on SAC’s farms will be used to elucidate these effects. The results of these studies will be used to feed into the whole-farm economic model and welfare costs approach used in this study. In addition new welfare indicators of the traits will be developed for use as management tools on farms. 4: Estimating welfare and economic costs Welfare improvements need to be assessed in an objective framework and the welfare cost/benefit of a particular farm practice evaluated. In addition selection indexes require relative economic values for a unit improvement in a breeding goal. This project will deliver the necessary information to implement new selection indexes containing the welfare and health traits as well as welfare assessments of the improvements.

Development and validation of methods for the detection and identification of sorbitol-fermenting verocytotxin-producing Escherichia coli O157:H-

1. To develop an identification medium for SF E.coli O175:H- strains. 2. To refine a detection procedure for SF E.coli O175:H- strains with inclusion of the optimised identification medium in a standard method for laboratory testing. 3. To develop a multiplex OCR for identification of vt, rfbo157, eae, spfA genes in isolates of SF E.coli O157:H-. 4. To validate, with statistical analysis, the developed SF E.coli O157:H- detection procedure using six different food and clinical matrices. 5. To compare the validated detection procedure for SF E.coli O157:H- strains with the current laboratory protocols for the examination of human clinical specimens.