Public attitudes toward different management scenarios for "surplus" dairy calves.

As awareness grows, some traditional management practices used by the dairy industry will be questioned by members of the public. Therefore, to maintain its social license to operate, the industry needs to account for public perspectives when developing future directions. Our aims were to assess attitudes of members of the public toward the management of surplus calves not needed for milk production on dairy farms, and to assess how specific calf management practices might influence these attitudes. A mixed-methods questionnaire was developed and distributed online in the United States and in Canada. After reading an introductory paragraph stating that surplus calves are generally used for meat production, participants were randomly allocated into groups and read 1 of 4 scenarios that described different surplus calf management practices in more detail. The scenarios followed a 2 × 2 factorial design, and the factors that differed were the calf's age at slaughter (≤2 wk vs. ≥12 mo), and whether the calf was separated from the cow at birth or sometime later. Data representative of key census demographics from 998 participants were analyzed. Quantitative data analysis included descriptive statistics, nonparametric tests, generalized partial credit models, and linear regression models. For qualitative data, we used reliability thematic analysis. Overall, participants were slightly positive in their attitudes toward the introductory paragraph, and participants in the groups in which the calf was slaughtered after 12 mo of age often specifically linked their acceptance of the practice to the fact that the calves' lives had a purpose (i.e., contributing meaningfully to the beef supply). In contrast, only 3% of the participants regarded a slaughter age of <1 mo as appropriate. Participants in the groups in which calves were slaughtered within 2 wk after birth had more negative attitudes, and these attitudes declined even further when the calf was separated from the cow soon after birth. Besides the 2 main factors (age at slaughter and cow-calf separation), information on pasture access, the healthiness of the meat from the calves, and the exact age of slaughter were also considered important by participants to make a more informed decision about their view on surplus calf management. Overall, our results indicate that failure by the dairy industry to provide assurances that excess dairy calves have a reasonable length of life and that this life has purpose (i.e., contributes to the beef supply chain) places the industry at odds with public values. Also, as awareness grows, the practice of early cow-calf separation will be increasingly questioned by the public; failure to begin discussions on this topic will increase the risk that future decisions about this topic will be made in the absence of the farmer.

Microclimate and pasture area preferences by dairy cows under high biodiversity silvopastoral system in Southern Brazil.

The aim of this study was to evaluate the influence of microclimate on dairy cows' behaviors and their preferences for different pasture areas under high biodiversity silvopastoral system (SPSnuclei) in a subtropical climate. We surveyed three different pasture areas under SPSnuclei: shaded area around the nuclei (SAN), unshaded area around the nuclei (UAN), and all-day sunny area distant from the nuclei (SDN). In each area, the microclimatic variables were measured-air temperature (°C), relative humidity (%), illuminance (lux), wind speed (m/s), and soil surface temperature (°C). In addition, the diurnal behaviors of 39 Jersey dairy cows were evaluated. Grazing, standing rest, lying rest, standing rumination, and lying rumination were registered by scans every 10 min; drinking water was observed continuously. Microclimate differed (p < 0.05) among the SPSnuclei areas. Areas around the nuclei provided better conditions of air temperature (SAN, 31.05 °C; UAN, 31.92 °C; SDN, 33.39 °C), illuminance (SAN, 5665 lx; UAN, 61,065 lx; SDN, 75,380 lx), and soil surface temperature (SAN, 27.35 °C; UAN, 32.38 °C; SDN, 35.87 °C). The frequency of use of each SPSnuclei area by dairy cows was different (p < 0.01); the highest frequencies of the grazing (SAN, 12.6%; UAN, 4.8%; SDN, 11.1%), rumination (SAN, 21.7%; UAN, 3.1%; SDN, 1.9%), and rest (SAN, 35.6%; UAN, 5.4%; SDN, 3.7%) were registered in the areas around the nuclei. The microclimate of the high biodiversity silvopastoral system leads the animals to perform grazing, ruminating, and resting preferentially on the areas around the nuclei even with no shade.

Sampling strategies for assessing lameness, injuries, and body condition score on dairy farms.

Our objective was to evaluate how sampling strategies (i.e., how many cows to sample and which animals to include) used in 4 dairy cattle welfare assessment programs affect the classification of dairy farms relative to thresholds of acceptability for animal-based measures. We predicted that classification performance would improve when more cows were sampled and when selecting from all lactating cows versus when some pens were excluded. On 38 freestall farms, we assessed all 12,375 cows for lameness, injuries on the tarsal (hock) and carpal joints, and body condition score and calculated the farm-level prevalence for each measure. Based on approaches used in the industry, we evaluated 6 sampling strategies generated using formulas with precision (d) of 15, 10, or 5% applied to either a single high-producing pen or all lactating cows; an additional sample was included with d = 10% applied to the entire herd, selecting lactating cows in proportion to their representation in the herd. For each sampling strategy, cow records were selected randomly (in 10,000 replicates) to calculate prevalence. The strategy of assessing all cows in the high-producing pen was also compared. Farms were classified as meeting (below) or failing to meet (above) thresholds of ≤15% moderate lameness; ≤20% moderate carpal or hock injuries; <10, <5, and ≤1% severe lameness; or injuries on the carpus or hock; and <5, <3, <1, or 0% thin cows. For each measure and threshold, we calculated pooled percent agreement, kappa, sensitivity, specificity, and positive and negative predictive value for each sampling strategy using true prevalence as the gold standard for herd classification. Across measures and thresholds, classification performance increased with the number of cows sampled [i.e., when narrower precision values (d = 5 vs. 10 vs. 15%) were used in the sample size calculation]. Because narrower precision values can dramatically increase sample size, assessment programs may need to consider both feasibility and the degree of misclassification they will accept. Applying the formula directly to lactating cows performed better than applying it to the entire herd and then selecting lactating cows in proportion to their representation in the herd. Farm classifications were similar whether cows in the hospital pen were included or excluded from the sample. Selecting all cows from the high-producing pen resulted in classifications similar to when including all lactating cows, suggesting that assessing cows from the high-producing pen may serve as an acceptable proxy for all lactating cows on the farm.

High biodiversity silvopastoral system as an alternative to improve the thermal environment in the dairy farms.

The aim of this work was to evaluate the influence of high biodiversity silvopastoral system (SPSnuclei) on microclimate and thermal comfort index thru a parallel with treeless pasture (TLP) during the four seasons of the year. Three conditions were determined for this study: shadowing area in SPSnuclei, sunny area in SPSnuclei, and sunny area in TLP. During two consecutive days in each season, the following microclimatic variables were collected: air temperature (°C), relative humidity (%), illuminance (lux), wind speed (m/s), and soil surface temperature (°C). The temperature and humidity index (THI) was calculated for each condition as indicative of thermal comfort. An influence analysis was carried out by generalized linear models to evaluate the system effects on the microclimatic variables. A confirmatory analysis was done with Wilcoxon-Mann-Whitney. Systems (SPSnuclei x TLP) influenced the microclimatic variables and THI (p < 0.05). The lowest means of air temperature, illuminance, wind speed, and soil surface temperature were found in SPSnuclei. As expected, autumn and winter presented a comfortable environment even on treeless pastureland. Only the SPSnuclei showed a comfortable environment for dairy production during spring. During summer, the TLP had a microclimate and thermal comfort index not suitable for dairy production already in the first hours of the day (THI between 79 and 85). We concluded that SPSnuclei provided better environment for pasture-based dairy production when compared to TLP. The high THI measured in TLP during summer could be a limiting factor on animal production.

Prevalence of lameness and leg lesions of lactating dairy cows housed in southern Brazil: Effects of housing systems.

Within the last few decades, the North American and European dairy industries have been collecting information about lameness and leg injury prevalence on dairy farms and have tried to develop solutions to mitigate these ailments. Few published articles report the prevalence of lameness and leg lesions in areas outside of those 2 regions, or how alternative housing systems, such as compost-bedded packs, affect the prevalence of these maladies. The objectives of this study were to compare the prevalence of lameness and leg lesions on confined dairies that used freestall, compost-bedded packs, or a combination of these 2 systems in Brazil. Data were collected in the autumn and winter of 2016 from 50 dairy farms located in Paraná state, including 12 compost-bedded pack dairies (CB), 23 freestall dairies (FS), and 15 freestall dairies that used compost-bedded packs for vulnerable cows (FS+C). A visit to the farm consisted of a management questionnaire, an inspection of the housing areas as well as the milking parlor, and an evaluation of all lactating cows as they exited the parlor for lameness (score 1-5), hygiene (score 0-2), body condition score (score 1-5), and hock and knee lesions (score 0-1). Median 1-way chi-squared test was used to compare production systems. We found no difference between farm types in management practices related to hoof health management or average daily milk production per cow [31 (29-33.9) kg/d; median (quartile 1-3)], percentage of Holstein cattle in the herd [100% (90-100%)], conception rate [35.8% (30.2-38%)], or pregnancy rate [15% (13.7-18%)]. The CB farms were smaller [85 (49.5-146.5) milking cows] than both the FS [270 (178-327.5) milking cows] and FS+C farms [360 (150-541.5) milking cows). The overall prevalence of severe lameness (score 4 and 5) across all farms was 21.2% (15.2-28.5%) but was lower on the CB farms [14.2% (8.45-15.5%)] in comparison to the FS [22.2% (16.8-26.7%)] and the FS+C farms [22.2% (17.4-32.8%)]. Less than 1% of all cows scored on CB farms were observed with swollen or wounded knees (or both), which was lower than either the FS or FS+C farms [7.4% (3.6-11.9%) and 6.4% (2.6-11.8%) of all cows scored, respectively]. The same pattern was found for hock lesions, where the farm-level prevalence within the 3 different housing types was 0.5% (0-0.9%), 9.9% (0.8-15.3%), and 5.7% (2.6-10.9%) for CB, FS, and FS+C farms, respectively. No differences between farm systems were observed for hygiene or body condition score. On average, 2.7% (0.8-10.9%) of lactating cows had a soiled side, 15.4% (2.1-37.4%) had dirty legs and 1.7% (0-9.3%) had dirty udders. The average herd-level body condition score across farms was 2.9 (2.9-3), with 0.86% of the all cows scored having a body condition score <2.5. These results indicate that lameness prevalence on confined dairies in Brazil is high and highlight the need for remedial changes in environmental design and management practices. We found that CB farms in this region had reduced lameness and lesions in relation to FS or FS+C dairies.

Citizens' views on the practices of zero-grazing and cow-calf separation in the dairy industry: Does providing information increase acceptability?

The primary aim of this study was to assess the influence of provision of information on lay citizens' opinions regarding 2 common management practices, zero-grazing and cow-calf separation. To aid in the interpretation of the findings, our secondary aim was to explore the awareness and opinions of Brazilian citizens about these practices. We surveyed a convenience sample of Brazilian citizens (192 men and 208 women), recruited in a public place, with the majority stating that they were largely unfamiliar with animal production and lived in urban environments. Participants were presented short scenarios with information on the primary production factors and welfare concerns for and against zero-grazing (n = 200) or cow-calf separation (n = 200). Participants were then asked to state their position (reject, indifferent, or support), and to provide the reason(s) justifying their position. Immediately following, participants were provided a short statement describing either zero-grazing or cow-calf separation, depending on what question they responded to in the first part. Two closed questions (Q) followed each of these statements: (Q1) "Are you aware of this practice?" with choices yes, somewhat, or no, and (Q2) "What is your position regarding this practice?" with choices reject, indifferent, or support. Only 31 and 33% of the respondents were aware of zero-grazing and cow-calf separation, respectively. Previous awareness of existence of practice did not influence levels of support. Provision of information resulted in more people rejecting the practices of zero-grazing and cow-calf separation. Participants' main justifications to reject zero-grazing and cow-calf separation focused on perceived negative effects of practices on farm animal welfare and product quality, and loss of naturalness. Survey participants, Brazilians living in urban environments, with little or no association with dairy production, were generally unaware that many cows do not have access to pasture and that cows are separated from their calf at birth. Independent of provision of additional information, most participants did not support these practices. Provision of brief explanatory information played a minor role in influencing people's views, but failed to result in general acceptance.

Readily Available Water Access is Associated with Greater Milk Production in Grazing Dairy Herds.

In this cross-sectional study, we measured the association between water provision and milk production on intensively managed small-scale grazing dairy herds. Farms (n = 53) were categorized according to water provision as follows: (1) Restricted-cows did not have access to a water trough while on pasture; and (2) Unrestricted-cows had free access to a water trough while on pasture. Herd main breed and feeding practices were included in a model to assess the effect of water provision category on farm average milk yield/cow/d. The effect of pasture condition and environmental variables on milk production were also assessed, however were not retained on the final model. Herds provided with unrestricted access to drinking water produced on average 1.7 L more milk per cow/d (p = 0.03) than herds with restricted access to drinking water. Predominantly Holstein herds produced 2.8 L more milk per cow/d (p < 0.01) than non-Holstein herds. Each extra kg of concentrate offered per day increased milk yield by 1.1 L/cow/d (p < 0.01). In conclusion, providing free access to drinking water while grazing was associated with greater milk production.

Is gene editing an acceptable alternative to castration in pigs?

Male piglets are commonly castrated to eliminate the risk of boar taint. Surgical castration is the commonly used procedure and is known to induce pain. Gene modification targeted at eliminating boar taint in male pigs has been proposed as a possible alternative to surgical castration. The aims of this study were to explore public acceptability of this biotechnology using a mixed methods approach. Quantitative data to assess acceptability of 570 participants from southern Brazil were analysed with multinomial logistic regression models and Spearman correlations; qualitative responses of the reasons provided in support of their position were coded into themes. Just over half of the participants (56%) considered gene modification of male pigs acceptable. Acceptability was lower among participants who grew up in an agricultural environment (ρ = 0.02), but was not influenced by sex, age, religion, urban or rural living, or level of education. Acceptability of gene modification of male pigs as an alternative to surgical castration was positively related to the perception of benefits (r = -0.56, ρ<0.0001) and negatively related to the participant's perception of risks (r = -0.35, ρ<0.0001). Acceptability was not related to knowledge of basic concepts of genetic biotechnologies (r = 0.06, ρ<0.14), or to awareness of issues related to pig castration or boar taint (r = 0.03, ρ<0.44), both of which were low among participants. Participants that considered gene modification of pigs acceptable justified their position using arguments that it improved animal welfare. In contrast, those that were not in favour were generally opposed to genetic modification. Unforeseen downstream consequences of using genetic modification in this manner was a major concern raised by over 80% of participants. Our findings suggest that perceived animal welfare may encourage public support of gene editing of food animals. However, potential risks of the technology need to be addressed and conveyed to the public, as many participants requested clarification of such risks as a condition for support.

Lameness on Brazilian pasture based dairies - Part 2: Conversations with farmers and dairy consultants.

A farmer or a dairy consultant's ability to identify and properly treat lame dairy cows is key to managing lameness on farms. However, this ability is dependent on their knowledge and perceptions regarding lameness. To date these topics are poorly understood in all dairy systems. To our knowledge, this is the first study that uses a qualitative approach to describe the perception of lameness in Brazilian pasture-based dairy farms. The aim of this study was firstly, to contextualize farmers and dairy consultants' culture and knowledge on the topic of lameness and, secondly, to understand how these factors may influence lameness management on the farms. In-depth face-to-face semi-structured interviews were done with participating farm owners (n = 21) and dairy consultants (n = 13). Thematic analyses of the interview content provided evidence that the dairy community's overarching culture around lameness acts as a barrier preventing positive actions targeting lameness control and prevention. The emerging themes identified indicate that lameness is a vague, ill-defined concept among both farmers and dairy consultants working in this region. There was a shared belief that pasture-based systems have a low risk for lameness. Furthermore, the prevailing culture for tackling lameness was reactive, particularly in the case of lame cows affected by physical trauma or environmental factors. Treatment was frequently delayed and the misuse of antibiotics was evident. Described community culture was rationalised via the cognitive dissonance and health belief models. We suggest that increased dialogue, including educational efforts within the community, may lead to increased sensitivity of risk perception of lameness within the community and in turn trigger appropriate diagnosis and treatment of lame cows.

American Citizens' Views of an Ideal Pig Farm.

Food animal production practices are often cited as having negative animal welfare consequences. The U.S. swine industry has not been exempt from such criticisms. Little is known, however, about how lay citizens who are not actively engaged in agricultural discussions, think about swine production. Thus, the aim of this study was to explore the views of people not affiliated with the swine industry on what they perceived to be the ideal pig/pork farm, and their associated reasons. Through an online survey, participants were invited to respond to the following open-ended question: "What do you consider to be an ideal pig/pork farm and why are these characteristics important to you?". Generally respondents considered animal welfare (e.g., space, freedom to move, and humane treatment), respondents considered the business operation role important for pork production (e.g., profitability, compliance with sanitary, environmental rules and regulations, and workers' rights), and naturalness (e.g., natural feeding, behaviours and life) important for pork production. Concerns relating to pigs' quality of life included space to move, feeding, contact with outdoors or nature, absence of pain, suffering and mistreatment. Perspectives were also raised regarding the ideal farm as a profitable business operation, clean, and with optimal sanitary conditions. Respondents also emphasized naturalness, frequently stating that pigs should have access to the outdoors, and rejected the use of hormones, antibiotics, and other chemicals for the purposes of increasing production. In summary, the findings of this study suggest that the U.S. swine industry should strive to adopt animal management practices that resonate with societal values, such as ensuring humane treatment, and the failure to do so could risk the sustainability of the swine industry.

Brazilian Citizens' Opinions and Attitudes about Farm Animal Production Systems.

The inclusion of societal input is needed for food animal production industries to retain their "social license to operate"; failure to engage with the public on this topic risks the long-term sustainability of these industries. The primary aim of this study was to explore the beliefs and attitudes of Brazilians citizens not associated with livestock production towards farm animal production. A related secondary aim was to identify the specific beliefs and attitudes towards systems that are associated with restriction of movement. Each participant was shown pictures representing two of five possible major food animal industries (laying hens, beef cattle, pregnant sows, lactating sows, and poultry meat). Participants were presented a six pages survey that included demographic questions plus two sets of two pictures and a series of questions pertaining to the pictures. Each set of pictures represented a particular industry where one picture represented a housing type that is associated with behavioural restrictions and the other picture represented a system that allowed for a greater degree of movement. Participants were asked their perceptions on the prevalence of each system in Brazil, then their preference of one picture vs. the other, and the reasons justifying their preference. Immediately following, the participant repeated the same exercise with the second set of two pictures representing another industry followed by the same series of questions as described above. Quantitative data were analysed with mixed effects logistic regression, and qualitative responses were coded into themes. The proportion of participants that believed animals are reared in confinement varied by animal production type: 23% (beef cattle), 82% (poultry), 81% (laying hens), and 60% (swine). A large majority (79%) stated that farm animals are not well-treated in Brazil. Overall, participants preferred systems that were not associated with behavioural restriction. The preference for free-range or cage-free systems was justified based on the following reasons: naturalness, animals' freedom to move, and ethics. A minority of participants indicated a preference for more restrictive systems, citing reasons associated with food security and food safety, increased productivity and hygiene. Our results suggest that the majority of our participants, preferred farm animal production systems that provide greater freedom of movement, which aligned with their perception that these systems are better for the animal. Our results provide some evidence that the current farm animal housing practices that are associated with restriction of movement, which are gaining traction in Brazil, may not align with societal expectations.

Prevalence and risk factors for transition period diseases in grazing dairy cows in Brazil.

The aim of this cross-sectional study was to describe the incidence risk of dystocia, retained placenta (RP), pathological recumbence (down cow), the prevalence of metritis and subclinical ketosis (SCK), and the risk factors for SCK, metritis, and RP in grazing dairy herds in Southern Brazil. Fifty-three herds were visited 2-6 times from February to October of 2015. Body condition score (BCS), breed, days in milk (DIM), parity and disease status were recorded for each cow that was between 3 and 21 DIM at the time of the visits. Management practices were determined using a survey and environmental inspection was performed on each visit. SCK was identified if blood ß-hydroxybutyrate was ≥1.2mmol/L and metritis by inspection of the vaginal discharge; cows were assessed once between 3 and 21 DIM. Multilevel logistic regression models, controlling for farm as a random effect, were built to identify risk factors for each disease and to assess the proportion of variance at the herd and cow levels. Models were constructed based on causal diagrams and variable screening. Overall, prevalence of SCK and metritis and incidence risk of RP were 21, 11 and 14%, respectively. Reported incidence risk of down cow was 6% and displaced abomasum was 1%. The odds (OR; 95% CI) of a cow having SCK were higher in herds with high (>10%) incidence of down cows (2.7; 1.4-5.0), limited access to water (1.9; 1.1-3.1), Jersey cows (OR: 2.2; 1.2-4.1) and in cows that were in third or greater lactation (2.9; 1.4-5.5). BCS 3.0-3.5 decreased the odds (0.4; 0.2-0.8) of metritis, while DIM, RP and being in a herd with a dirty holding area increased the odds of metritis by 1.1 (1.1-1.2), 19.5 (9.9-38.3) and 2.1 (1.0-4.2) fold, respectively. Parity >2 and dystocia increased the odds of RP by 2.4 (1.2-4.6) and 3.0 (1.6-5.4) fold, respectively. Jersey breed, use of a maternity pen and keeping the newborn calf with the cow >12h decreased the odds of having RP by 0.1 (0.0-0.4), 0.5 (0.3-1.0) and 0.4 (0.2-0.8) times, respectively. The variation in disease occurrence was largely dependent on cow-level factors. However, herd level risk factors also influenced disease occurrence and should be considered in order to design better preventive transition period diseases protocols.

Effects of Degree and Timing of Social Housing on Reversal Learning and Response to Novel Objects in Dairy Calves.

Rodents and primates deprived of early social contact exhibit deficits in learning and behavioural flexibility. They often also exhibit apparent signs of elevated anxiety, although the relationship between these effects has not been studied. To investigate whether dairy calves are similarly affected, we first compared calves housed in standard individual pens (n = 7) to those housed in a dynamic group with access to their mothers (n = 8). All calves learned to approach the correct stimulus in a visual discrimination task. Only one individually housed calf was able to re-learn the task when the stimuli were reversed, compared to all but one calf from the group. A second experiment investigated whether this effect might be explained by anxiety in individually housed animals interfering with their learning, and tested varying degrees of social contact in addition to the complex group: pair housing beginning early (approximately 6 days old) and late (6 weeks old). Again, fewer individually reared calves learned the reversal task (2 of 10 or 20%) compared to early paired and grouped calves (16 of 21 or 76% of calves). Late paired calves had intermediate success. Individually housed calves were slower to touch novel objects, but the magnitude of the fear response did not correlate with reversal performance. We conclude that individually housed calves have learning deficits, but these deficits were not likely associated with increased anxiety.

Determinants of the annual pattern of reproduction in mature male Merino and Suffolk sheep: responses to a nutritional stimulus in the breeding and non-breeding seasons.

This study was designed to test whether an acute improvement in diet would increase gonadotrophin secretion and testicular growth in strongly photoperiod-responsive Suffolk rams and weakly photoperiod-responsive Merino rams in both the breeding (February-March) and the non-breeding (July-August) seasons. Mature rams (n = 5 or 6) of these breeds were fed a maintenance diet (0.9 kg chaff + 100 g lupin grain) or the same diet supplemented with 1.5 kg lupin grain for 42 days in each season. Lupin grain is a rich source of both energy and protein. Testosterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) were measured in plasma from blood sampled every 20 min for 24 h on Days -1, 12 and 35 relative to the change in feeding. In rams supplemented with lupins, body mass increased in both breeds in both seasons (P < 0.001). Scrotal circumference and LH pulse frequency increased with lupin supplementation in both seasons (P < 0.003) in Merinos, but only during the breeding season (P < 0.003) in Suffolks. Plasma FSH concentrations were affected by diet only during the breeding season, being elevated on Day 12 in lupin-supplemented rams of both breeds (P < 0.05). It was concluded that Merino rams exhibit reproductive responses to improved nutrition irrespective of time of the year, whereas Suffolk rams respond to nutrition only when the hypothalamic reproductive centres are not inhibited by photoperiod. Thus, Suffolks do respond to nutrition, just as Merinos do, but only when photoperiod allows. This difference between breeds appears to be a result of differences in the neuroendocrine pathways that control pulsatile gonadotrophin-releasing hormone secretion.

Determinants of the annual pattern of reproduction in mature male Merino and Suffolk sheep: modification of responses to photoperiod by an annual cycle in food supply.

Rams of a 'Mediterranean breed' (Merino) and a 'temperate breed' (Suffolk) were compared to determine how much of the differences between their reproductive seasons is owing to variation in their responses to photoperiodic and nutritional cues. In a previous study, both nutritional and photoperiodic inputs were held constant, and it was found that the two breeds show similar endogenous rhythms and, when the animals are challenged with a Mediterranean photoperiodic cycle, these endogenous rhythms are similarly modified. The present study tested whether an annual cycle in the supply of forage might modify the patterns that are generated by the interaction between photoperiod and endogenous rhythms. Both breeds were subjected to a simulated 'Mediterranean' annual cycle in photoperiod (10L:14D to 14D:10L) and provided with either constant food supply or a simulated 'Mediterranean' annual cycle in food supply. In Merino rams, testicular growth responded to photoperiod, but nutrition dominated those responses. In Suffolk rams, changes in testicular size can be completely out of phase with changes in body mass because they are driven primarily by photoperiod, with only subtle responses to changes in diet. The cycle of testicular growth in the Suffolk was driven by changes in the secretion of gonadotrophins (follicle-stimulating hormone concentrations and luteinizing hormone pulse frequency). By contrast, in the Merino, the nutritionally driven seasonal cycle of testicular growth was associated primarily with changes in body mass and this relationship could not always be explained by changes in gonadotrophin secretion. Melatonin secretion was not affected by food supply. Thus, the 'Mediterranean' and 'temperate' genotypes have similar endogenous rhythms that are similarly modified by photoperiod but, with respect to seasonal changes in nutrition, they differ in both the nature of their reproductive response and the physiological mechanisms that mediate those responses.

Minimizing aggression during mixing of gestating sows with supplementation of a tryptophan-enriched diet.

Gestation stalls are criticized for its negative physical and psycho-physiological effects on sow welfare. Group housing benefits sow well-being and when planned properly can minimize aggression during mixing. This study aimed to evaluate the effect of short-term feeding of a TRP-enriched diet at a concentration of 220% the control (CTL) diet, on aggressiveness at mixing of sows at 4weeks of gestation. Treatment diets were fed for 7 consecutive days; from days 1 to 5 sows were housed in stalls, early in the morning on day 6 sows were grouped by parity and assessed until day 7. Eighteen pens with 4 sows each (n=72) of similar parity were assigned to CTL and TRP treatments. Sows' behaviors were recorded daily for 12h, from days 1 to 7. Inactive and active behaviors (alert, walking (pen), rooting, feeding, drinking, eliminating), stereotypic behaviors (bar biting and sham-chewing), and postures (standing, sitting, lying) were assessed by 10-minute scan sampling. Occurrence of agonistic interactions, number of actions such as bites, head knocks and pursuits and their sum per interaction were recorded for each pen using 2-h continuous behavioral observation, at days 6 and 7. Skin lesion scores were assessed from each sow at day 5 and at 48h post-mixing, using a sow body map subdivided into anterior, central and posterior body regions. A linear mixed model with day as repeated measure, stall or pen as experimental unit, tested the fixed effects of treatment, day, period within day, their interactions, and block by treatment interaction; stall (trt) or pen (trt) as appropriate was used as random effect. Blood concentration of TRP was higher on the mixing day in TRP-fed sows compared to baseline (76%) and CLT-fed sows at mixing (79%; P<0.05), while serotonin concentration did not differ between treatments (P>0.05). The TRP-enriched diet was effective in reducing sham-chewing in stall housed sows of parity 5-9 (P<0.05). In pens, TRP-fed sows spent more time rooting (TRP=28.0 vs. CTL=20.7±1.0%; P<0.05) and consequently less time lying down than CTL-fed sows (TRP=56.1 vs. CTL=65.1±2.0%; P<0.05). The total number of offensive actions per interaction was greater in the morning than afternoon for both days (P<0.05), but this was less evident in TRP-fed compared to CTL sows mainly on the morning following mixing (3.4 vs. 7.2±1.0, respectively; Trt∗period (day)=P<0.05). The average lesion score was lower in the anterior body region of TRP-fed compared to CTL sows (2.1 vs. 2.5±0.2; P<0.05), the most affected area during fights. The TRP-enriched diet reduced sow aggression while increasing behavioral activity, as evidenced by more time rooting and standing while sows had fewer offensive actions per agonistic interaction and lower skin lesion score 48h post-mixing. A TRP enriched diet provided to gestating sows for a short period prior to social mixing and continued for a short time after is an effective means of reducing aggression and improving the welfare of sows during group formation.

A survey of management practices that influence performance and welfare of dairy calves reared in southern Brazil.

Here we report dairy calf management practices used by 242 smallholder family farmers in the South of Brazil. Data were collected via a semi-structured questionnaire with farmers, inspection of the production environment and an in-depth interview with a sample of 26 farmers. Herds had an average of 22.3 lactating cows and an average milk production of 12.7 L/cow/day. Calves were dehorned in 98% of the farms, with a hot iron in 95%. Male calves were castrated in 71% of the farms; methods were surgery (68%), emasculator (29%), or rubber rings (3%). No pain control was used for these interventions. In 51% of the farms all newborn male calves were reared, sold or donated to others; in 35% all newborn males were killed on the farm. Calves were separated from the dam up to 12 h after birth in 78% of the farms, and left to nurse colostrum from the dam without intervention in 55% of the farms. The typical amount of milk fed to calves was 4 L/day until a median age of 75 days. In 40% of the farms milk was provided in a bucket, in 49% with bottles, and in 11% calves suckled from a cow. Solid feeding in the milk-feeding period started at a median age of 10 days. Calves were housed individually in 70% of the farms; in 81% of the farms calves were housed in indoor pens, in 6% in outdoor hutches and in 13% they were kept on pasture. Diarrhoea was reported as the main cause of calf mortality in 71% of the farms. Farmers kept no records of calf disease, mortality, or use of medicines. Changing the scenario identified in this survey is essential to support the sustainable development of dairy production, an activity of great economic and social relevance for the region.

Separation from the dam causes negative judgement bias in dairy calves.

Negative emotional states in humans are associated with a negative (pessimistic) response bias towards ambiguous cues in judgement tasks. Every mammalian young is eventually weaned; this period of increasing nutritional and social independence from the dam is associated with a pronounced behavioural response, especially when weaning is abrupt as commonly occurs in farm animals. The aim of the current study was to test the effect of separation from the cow on the responses of dairy calves in a judgement task. Thirteen Holstein calves were reared with their dams and trained to discriminate between red and white colours displayed on a computer monitor. These colours predicted reward or punishment outcomes using a go/no-go task. A reward was provided when calves approached the white screen and calves were punished with a timeout when they approached the red screen. Calves were then tested with non-reinforced ambiguous probes (screen colours intermediate to the two training colours). "GO" responses to these probes averaged (± SE) 72±3.6% before separation but declined to 62±3.6% after separation from the dam. This bias was similar to that shown by calves experiencing pain in the hours after hot-iron dehorning. These results provide the first evidence of a pessimistic judgement bias in animals following maternal separation and are indicative of low mood.

Minimising the stress of weaning of beef calves: a review.

Weaning of beef calves is usually done abruptly and early compared to the natural weaning of the species, and is associated with simultaneous exposure of calves to a range of social and environmental stressors. Behavioural and physiological responses to weaning indicate detrimental effects on the welfare of these animals. The development and assessment of weaning methods aiming at reducing or avoiding this problem must be supported by scientific knowledge of the morphological, physiological and psychological mechanisms involved in the establishment, maintenance and braking of the cow-calf bond. Solutions also depend on the understanding of the various stressors associated with weaning, among which are the change in diet, cessation of nursing, separation from the dam, the change to a new spatial environment and the need for social reorganization following removal of the adults from the group. This review discusses these issues and assesses the effectiveness of the methods so far proposed for improving the welfare of beef calves during the weaning period.