Application of the speed-duration relationship to normalize the intensity of high-intensity interval training

The tolerable duration of continuous high-intensity exercise is determined by the hyperbolic Speed-tolerable duration (S-tLIM) relationship. However, application of the S-tLIM relationship to normalize the intensity of High-Intensity Interval Training (HIIT) has yet to be considered, with this the aim of present study. Subjects completed a ramp-incremental test, and series of 4 constant-speed tests to determine the S-tLIM relationship. A sub-group of subjects (n = 8) then repeated 4 min bouts of exercise at the speeds predicted to induce intolerance at 4 min (WR4), 6 min (WR6) and 8 min (WR8), interspersed with bouts of 4 min recovery, to the point of exercise intolerance (fixed WR HIIT) on different days, with the aim of establishing the work rate that could be sustained for 960 s (i.e. 4×4 min). A sub-group of subjects (n = 6) also completed 4 bouts of exercise interspersed with 4 min recovery, with each bout continued to the point of exercise intolerance (maximal HIIT) to determine the appropriate protocol for maximizing the amount of high-intensity work that can be completed during 4×4 min HIIT. For fixed WR HIIT tLIM of HIIT sessions was 399±81 s for WR4, 892±181 s for WR6 and 1517±346 s for WR8, with total exercise durations all significantly different from each other (P<0.050). For maximal HIIT, there was no difference in tLIM of each of the 4 bouts (Bout 1: 229±27 s; Bout 2: 262±37 s; Bout 3: 235±49 s; Bout 4: 235±53 s; P>0.050). However, there was significantly less high-intensity work completed during bouts 2 (153.5±40. 9 m), 3 (136.9±38.9 m), and 4 (136.7±39.3 m), compared with bout 1 (264.9±58.7 m; P>0.050). These data establish that WR6 provides the appropriate work rate to normalize the intensity of HIIT between subjects. Maximal HIIT provides a protocol which allows the relative contribution of the work rate profile to physiological adaptations to be considered during alternative intensity-matched HIIT protocols

The ‘surplus’ dairy calf: understanding dairy-beef supply chain relationships and the implications for calf welfare

Main Findings• Excess dairy-origin calves are increasingly being sold into the beef supply chain, rather thanbeing slaughtered at a young age. Calves are sold from the dairy farm of origin to dedicated calfrearing enterprises or to calf procurement companies who distribute calves to farms• We interviewed dairy farmers (calf producers), calf rearers and procurement companies to gainan insight into the basis of this relationship, calf care and information transfer. The implicationsfor calf health and welfare were extracted• Of those dairy farmers interviewed, the majority sold calves directly to calf rearers, which likelyreduces transport time and mixing between groups of calves, which may be detrimental for healthand disrupts social bonds of calves• Farmers do not like the term ‘surplus calf’. They viewed these animals as a valuable economicpart of their farming enterprises• The relationship between calf producers and calf rearers is based on personal reputation andtrust. Calf producers do not want to sell poor calves to calf rearers. As a result, calves destinedfor beef are more likely to receive the same standard of care and nutrition as other calves• There is the potential for data on health status, vaccination records and growth to be transferre

AW0521 - Determining potential impacts of Precision Breeding on Animal Welfare FINAL REPORT

1. Introduction of the Genetic Technology (Precision Breeding) Act in 2023 paved the way for the use of precision breeding technologies (e.g., genome editing) in livestock in England. However, while recognising that there may be major benefits inferred by increased disease resistance and other traits, concern has been raised about the possible wider effects of the use of the technology on animal welfare. This project aimed to understand the current situation with respect to level of use and development of precision-bred animals and to consider what welfare indicators should be used to assess welfare in general, and for specific types of edits.2. A mapping and scoping phase indicated that few companies have initiated data collection or development of precision-bred animals that might be present in/be imported into England. The pig and fish sectors were the only sectors to indicate that development has commenced. Mapping suggested that the first animals are bred in research/university environments where animals are kept under the auspices of ASPA. Apart from the fish and pig sectors, the chicken, cattle and sheep sectors also expressed some interest in developing precision-bred animals in the near future (I.e.., in the next 5 years). For the equine sector, only a few stakeholders expressed some interest in using precison-breeding technologies to improve specific traits such as disease resistance or resilience to environmental stress, but there is no intention to use PB in equine breeding practice in the immediate future. 3. Expert consultation and a review of the literature indicated that the Five Domains Model was the most appropriate of current animal welfare models to use to build indicator lists. This model includes nutritional state, health, environmental responses, behavioural interactions and mental state. While most animal welfare assessment protocols assess the effects of housing and management on welfare outcomes for animals, it is biological functioning that is the most important aspect to assess in the precision breeding context.4. Welfare assessment indicator lists were drawn up for the three main species that are in the most advanced stage of use of precision breeding. These were pigs, poultry and salmon. Indicator lists were constructed that drew on industry handbooks, current animal welfare assessment schemes and relevant literature. These indicator lists aimed to facilitate a holistic assessment of overall animal welfare to detect changes in functioning across the Five Domains. The indicator lists contain welfare indicators that assess the animal across its EVID4 Evidence Project Final Report (Rev. 06/11) Page 3 of 21lifetime, compared with a control group of the same breed and same age and sex ratio. Three levels of assessment were considered: basic, enhanced and enhanced plus. The basic level of assessment does not fully cover the five domains in all three species, so SRUC strongly recommends that the enhanced level of assessment is adopted.5. In addition to the overall welfare assessment indicator lists, three cases studies were considered to determine how and when to add additional welfare indicators to these lists. The aim was to cover welfare-related traits and production-relate traits. To this end, the specific traits considered were PRRS virus, avian influenza and the hypothetical case of myostatin in fish. As animals carrying these edits are not available for inspection, a risk assessment was limited to ‘consequence characterisation’: ie., identifying possible consequences of gene editing on welfare. These case studies showed that a wider consideration of the edit and the pathways involved needs to be investigated. In addition to the overall holistic assessment using the Basic, Enhanced or Enhanced Plus levels, assessment using additional welfare indicators that are relevant to the specific edit may be required.6. Three webinars/workshops were held to present results to stakeholders. In addition, a meeting was held with equine stakeholders and numerous discussions were held with individual stakeholders to gain information on aspects of precision breeding

AW0521 - Determining potential impacts of Precision Breeding on Animal Welfare FINAL REPORT

1. Introduction of the Genetic Technology (Precision Breeding) Act in 2023 paved the way for the use of precision breeding technologies (e.g., genome editing) in livestock in England. However, while recognising that there may be major benefits inferred by increased disease resistance and other traits, concern has been raised about the possible wider effects of the use of the technology on animal welfare. This project aimed to understand the current situation with respect to level of use and development of precision-bred animals and to consider what welfare indicators should be used to assess welfare in general, and for specific types of edits.2. A mapping and scoping phase indicated that few companies have initiated data collection or development of precision-bred animals that might be present in/be imported into England. The pig and fish sectors were the only sectors to indicate that development has commenced. Mapping suggested that the first animals are bred in research/university environments where animals are kept under the auspices of ASPA. Apart from the fish and pig sectors, the chicken, cattle and sheep sectors also expressed some interest in developing precision-bred animals in the near future (I.e.., in the next 5 years). For the equine sector, only a few stakeholders expressed some interest in using precison-breeding technologies to improve specific traits such as disease resistance or resilience to environmental stress, but there is no intention to use PB in equine breeding practice in the immediate future. 3. Expert consultation and a review of the literature indicated that the Five Domains Model was the most appropriate of current animal welfare models to use to build indicator lists. This model includes nutritional state, health, environmental responses, behavioural interactions and mental state. While most animal welfare assessment protocols assess the effects of housing and management on welfare outcomes for animals, it is biological functioning that is the most important aspect to assess in the precision breeding context.4. Welfare assessment indicator lists were drawn up for the three main species that are in the most advanced stage of use of precision breeding. These were pigs, poultry and salmon. Indicator lists were constructed that drew on industry handbooks, current animal welfare assessment schemes and relevant literature. These indicator lists aimed to facilitate a holistic assessment of overall animal welfare to detect changes in functioning across the Five Domains. The indicator lists contain welfare indicators that assess the animal across its EVID4 Evidence Project Final Report (Rev. 06/11) Page 3 of 21lifetime, compared with a control group of the same breed and same age and sex ratio. Three levels of assessment were considered: basic, enhanced and enhanced plus. The basic level of assessment does not fully cover the five domains in all three species, so SRUC strongly recommends that the enhanced level of assessment is adopted.5. In addition to the overall welfare assessment indicator lists, three cases studies were considered to determine how and when to add additional welfare indicators to these lists. The aim was to cover welfare-related traits and production-relate traits. To this end, the specific traits considered were PRRS virus, avian influenza and the hypothetical case of myostatin in fish. As animals carrying these edits are not available for inspection, a risk assessment was limited to ‘consequence characterisation’: ie., identifying possible consequences of gene editing on welfare. These case studies showed that a wider consideration of the edit and the pathways involved needs to be investigated. In addition to the overall holistic assessment using the Basic, Enhanced or Enhanced Plus levels, assessment using additional welfare indicators that are relevant to the specific edit may be required.6. Three webinars/workshops were held to present results to stakeholders. In addition, a meeting was held with equine stakeholders and numerous discussions were held with individual stakeholders to gain information on aspects of precision breeding

Food waste in primary production: Milk loss with mitigation potentials

Sources and quantities of milk loss in primary production are presented in this paper through an analysis of results from a 2018 survey. Responses from 43 dairy farms in Scotland showed that milk losses occurred due to withdrawal periods for veterinary treatment, parlor infrastructure, and lapses in management routine. A partial life cycle assessment detailed flows of milk from cow to farm gate and captured farm inputs such as imported feeds and fertilizers. Incidence of animal health events such as mastitis, that routinely lead to milk withdrawal were quantified alongside strategies carried out by farmers to reduce milk loss. Treatment for mastitis accounted for 76% of all milk withdrawal days and the remaining 24% stemmed from therapies for health events such as uterine disorders and lameness. Withdrawal periods for mastitis treatments averaged 4.5 days, with a mean incidence of 20% of cows in a herd. Across all farms, an average of 98.2% of total milk produced was sold, 0.66% was purposely retained, 0.55% was rejected due to antibiotic residues, 0.5% was lost from parlor to bulk tank infrastructure and a further 0.09% was rejected by the processor. Carbon footprints found greenhouse gas (GHG) emissions averaged 0.849 kg CO2e/kg across farms for the milking herd. A scenario of 20% fewer withdrawal days reduced GHG's on average by 0.6%. Additional mitigation was attained by reductions in milk loss from parlor infrastructure and the bulk tank, and this showed a 1% reduction in GHG emissions could be achieved through higher volumes of milk sales. Categorizing responses by management system type highlighted differences in proportional losses between all year round housed and conventional grazing regimes. The most predominant health disorder leading to milk withdrawal was mastitis, however losses due to other health events and parlor infrastructure were not insignificant on Scottish dairy farms

AW0521 - Determining potential impacts of Precision Breeding on Animal Welfare FINAL REPORT

1. Introduction of the Genetic Technology (Precision Breeding) Act in 2023 paved the way for the use of precision breeding technologies (e.g., genome editing) in livestock in England. However, while recognising that there may be major benefits inferred by increased disease resistance and other traits, concern has been raised about the possible wider effects of the use of the technology on animal welfare. This project aimed to understand the current situation with respect to level of use and development of precision-bred animals and to consider what welfare indicators should be used to assess welfare in general, and for specific types of edits.2. A mapping and scoping phase indicated that few companies have initiated data collection or development of precision-bred animals that might be present in/be imported into England. The pig and fish sectors were the only sectors to indicate that development has commenced. Mapping suggested that the first animals are bred in research/university environments where animals are kept under the auspices of ASPA. Apart from the fish and pig sectors, the chicken, cattle and sheep sectors also expressed some interest in developing precision-bred animals in the near future (I.e.., in the next 5 years). For the equine sector, only a few stakeholders expressed some interest in using precison-breeding technologies to improve specific traits such as disease resistance or resilience to environmental stress, but there is no intention to use PB in equine breeding practice in the immediate future. 3. Expert consultation and a review of the literature indicated that the Five Domains Model was the most appropriate of current animal welfare models to use to build indicator lists. This model includes nutritional state, health, environmental responses, behavioural interactions and mental state. While most animal welfare assessment protocols assess the effects of housing and management on welfare outcomes for animals, it is biological functioning that is the most important aspect to assess in the precision breeding context.4. Welfare assessment indicator lists were drawn up for the three main species that are in the most advanced stage of use of precision breeding. These were pigs, poultry and salmon. Indicator lists were constructed that drew on industry handbooks, current animal welfare assessment schemes and relevant literature. These indicator lists aimed to facilitate a holistic assessment of overall animal welfare to detect changes in functioning across the Five Domains. The indicator lists contain welfare indicators that assess the animal across its EVID4 Evidence Project Final Report (Rev. 06/11) Page 3 of 21lifetime, compared with a control group of the same breed and same age and sex ratio. Three levels of assessment were considered: basic, enhanced and enhanced plus. The basic level of assessment does not fully cover the five domains in all three species, so SRUC strongly recommends that the enhanced level of assessment is adopted.5. In addition to the overall welfare assessment indicator lists, three cases studies were considered to determine how and when to add additional welfare indicators to these lists. The aim was to cover welfare-related traits and production-relate traits. To this end, the specific traits considered were PRRS virus, avian influenza and the hypothetical case of myostatin in fish. As animals carrying these edits are not available for inspection, a risk assessment was limited to ‘consequence characterisation’: ie., identifying possible consequences of gene editing on welfare. These case studies showed that a wider consideration of the edit and the pathways involved needs to be investigated. In addition to the overall holistic assessment using the Basic, Enhanced or Enhanced Plus levels, assessment using additional welfare indicators that are relevant to the specific edit may be required.6. Three webinars/workshops were held to present results to stakeholders. In addition, a meeting was held with equine stakeholders and numerous discussions were held with individual stakeholders to gain information on aspects of precision breeding

Impact of early social housing on the play behavior of neonatal and post-weaning dairy calves

We aimed to assess the impact of early life housing and play experiences on neonatal and weaned calves play behavior. A total of 96 female dairy calves were recruited from four Scottish dairy farms and assigned to individual (n = 48), paired (n = 24) or group (n = 24) housing at birth. Play behavior was measured using IceTag accelerometers (Peacock Technology, UK) during two experimental periods in the same cohort of calves, at neonatal and weaned stages. A mixed-effects negative binomial regression analysis was used to assess how early social housing influences the play behavior of neonatal and weaned calves. The analysis also considered the impact of early play on the play behavior of weaned calves. Calves housed in paired or group pens from birth performed significantly more neonatal play compared to calves housed individually from birth. No lasting effect of early life housing on weaned calf play behavior was observed. There was no correlation between counts of neonatal and weaned calf play. Calves with lower neonatal playfulness showed a numerical increase in play behavior after weaning compared to those with higher neonatal playfulness. These findings add to the growing body of literature indicating that early life social housing provides a more positive welfare experience for pre-weaned dairy calves. The study also highlights the need for future research to understand the impact of rearing experiences and different management systems on play behavior in weaned calves

Combined effects of time spent in physical activity, sedentary behaviors and sleep on obesity and cardio-metabolic health markers: a novel compositional data analysis approach

<div><p>The associations between time spent in sleep, sedentary behaviors (SB) and physical activity with health are usually studied without taking into account that time is finite during the day, so time spent in each of these behaviors are codependent. Therefore, little is known about the combined effect of time spent in sleep, SB and physical activity, that together constitute a composite whole, on obesity and cardio-metabolic health markers. Cross-sectional analysis of NHANES 2005–6 cycle on N = 1937 adults, was undertaken using a compositional analysis paradigm, which accounts for this intrinsic codependence. Time spent in SB, light intensity (LIPA) and moderate to vigorous activity (MVPA) was determined from accelerometry and combined with self-reported sleep time to obtain the 24 hour time budget composition. The distribution of time spent in sleep, SB, LIPA and MVPA is significantly associated with BMI, waist circumference, triglycerides, plasma glucose, plasma insulin (all p<0.001), and systolic (p<0.001) and diastolic blood pressure (p<0.003), but not HDL or LDL. Within the composition, the strongest positive effect is found for the proportion of time spent in MVPA. Strikingly, the effects of MVPA replacing another behavior and of MVPA being displaced by another behavior are asymmetric. For example, re-allocating 10 minutes of SB to MVPA was associated with a lower waist circumference by 0.001% but if 10 minutes of MVPA is displaced by SB this was associated with a 0.84% higher waist circumference. The proportion of time spent in LIPA and SB were detrimentally associated with obesity and cardiovascular disease markers, but the association with SB was stronger. For diabetes risk markers, replacing SB with LIPA was associated with more favorable outcomes. Time spent in MVPA is an important target for intervention and preventing transfer of time from LIPA to SB might lessen the negative effects of physical inactivity.</p></div