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Edinburgh of the Seven Seas, Saint Helena

Duthie C.-A.,Beef and Sheep Research Center | Rooke J.A.,Beef and Sheep Research Center | Troy S.,Beef and Sheep Research Center | Hyslop J.J.,SAC Consulting Ltd. | And 3 more authors.
Animal | Year: 2015

Adding nitrate to the diet or increasing the concentration of dietary lipid are effective strategies for reducing enteric methane emissions. This study investigated their effect on health and performance of finishing beef cattle. The experiment was a two×two×three factorial design comprising two breeds (CHX, crossbred Charolais; LU, Luing); two basal diets consisting of (g/kg dry matter (DM), forage to concentrate ratios) 520 : 480 (Mixed) or 84 : 916 (Concentrate); and three treatments: (i) control with rapeseed meal as the main protein source replaced with either (ii) calcium nitrate (18 g nitrate/kg diet DM) or (iii) rapeseed cake (RSC, increasing acid hydrolysed ether extract from 25 to 48 g/kg diet DM). Steers (n=84) were allocated to each of the six basal diet×treatments in equal numbers of each breed with feed offered ad libitum. Blood methaemoglobin (MetHb) concentrations (marker for nitrate poisoning) were monitored throughout the study in steers receiving nitrate. After dietary adaptation over 28 days, individual animal intake, performance and feed efficiency were recorded for a test period of 56 days. Blood MetHb concentrations were low and similar up to 14 g nitrate/kg diet DM but increased when nitrate increased to 18 g nitrate/kg diet DM (P<0.001). An interaction between basal diet and day (P<0.001) indicated that MetHb% was consistently greater in Concentrate – than Mixed-fed steers at 18 g nitrate/kg diet DM. Maximum individual MetHb% was 15.4% (of total Hb), which is lower than considered clinically significant (30%). MetHb concentrations for individual steers remained consistent across time. Concentrate-fed steers were more efficient (lower residual feed intake (RFI) values) than Mixed-fed steers (P<0.01), with lower dry matter intake (DMI) (kg/day) (P<0.001) and similar average daily gain (ADG). CHX steers were more efficient (lower RFI; P<0.01) than LU steers with greater ADG (P<0.01), lower DMI (/kg BW; P<0.01) and lower fat depth (P<0.001). ADG, BW or DMI did not differ across dietary treatments (P>0.05). Neither basal diet nor treatment affected carcass quality (P>0.05), but CHX steers achieved a greater killing out proportion (P<0.001) than LU steers. Thus, adding nitrate to the diet or increasing the level of dietary lipid through the use of cold-pressed RSC, did not adversely affect health or performance of finishing beef steers when used within the diets studied. © The Animal Consortium 2015 Source

Athanasiadou S.,Animal and Veterinary science Group
Veterinary Parasitology | Year: 2012

The dissection of the molecular interactions between nutrition and immunity to nematodes is of strategic importance to predict the risk of infection, define disease predisposition and develop sustainable measures for parasite control in ruminants. Despite the evidence on the effects of nutrition on the manifestations of immunity to gastrointestinal parasites at phenotypic level, the lack of progress on the characterisation of the molecular interactions is directly related to the current lack of appropriate tools for such advancements, including fully sequenced and annotated genomes and immunological tools for small ruminants. To overcome such constraints and achieve rapid progress in exploring the molecular interactions between nutrition and immunity to nematodes, it is proposed here that we capitalise more on the advancements in small mammal models. In this paper, first the literature deriving from growing animals is reviewed, where most evidence originates from primary infection models. The focus is then shifted on peri-parturient animals; the immunomodulatory effects of nutrition are investigated during re-infection. Finally, an approach is suggested on how advancements made in the rodent models, can be utilised in order to expand our understanding in sheep and provide specific examples on how this should work to address sustainable parasite control in ruminants. © 2012 . Source

Fleming P.A.,Murdoch University | Wickham S.L.,Murdoch University | Stockman C.A.,Murdoch University | Verbeek E.,Agresearch Ltd. | And 4 more authors.
Animal | Year: 2015

Qualitative behavioural assessment (QBA) is based on observers' ability to capture the dynamic complexity of an animal's demeanour as it interacts with the environment, in terms such as tense, anxious or relaxed. Sensitivity to context is part of QBA's integrative capacity and discriminatory power; however, when not properly managed it can also be a source of undesirable variability and bias. This study investigated the sensitivity of QBA to variations in the visual or verbal information provided to observers, using free-choice profiling (FCP) methodology. FCP allows observers to generate their own descriptive terms for animal demeanour, against which each animal's expressions are quantified on a visual analogue scale. The resulting scores were analysed with Generalised Procrustes Analysis (GPA), generating two or more multi-variate dimensions of animal expression. Study 1 examined how 63 observers rated the same video clips of individual sheep during land transport, when these clips were interspersed with two different sets of video footage. Scores attributed to the sheep in the two viewing sessions correlated significantly (GPA dimension 1: r s=0.95, P<0.001, GPA dimension 2: r s=0.66, P=0.037) indicating that comparative rankings of animals on expressive dimensions were highly similar, however, their mean numerical scores on these dimensions had shifted (RM-ANOVA: Dim1: P<0.001, Dim2: P<0.001). Study 2 investigated the effect of being given different amounts of background information on two separate groups of observers assessing footage of 22 individual sheep in a behavioural demand facility. One group was given no contextual information regarding this facility, whereas the second group was told that animals were moving towards and away from a feeder (in view) to access feed. Scores attributed to individual sheep by the two observer groups correlated significantly (Dim1: r s=0.92, P<0.001, Dim2: r s=0.52, P=0.013). A number of descriptive terms were generated by both observer groups and used in similar ways, other terms were unique to each group. The group given additional information about the experimental facility scored the sheep's behaviour as more 'directed' and 'focused' than observers who had not been told. Thus, in neither of the two studies did experimentally imposed variations in context alter the characterisations of animals relative to each other, but in Study 1 this did affect the mean numerical values underlying these characterisations, indicating a need for careful attention to the use of visual analogue scales. © The Animal Consortium 2015. Source

Andreasen S.N.,Copenhagen University | Wemelsfelder F.,Animal and Veterinary science Group | Sandoe P.,Copenhagen University | Forkman B.,Copenhagen University
Applied Animal Behaviour Science | Year: 2013

The effort to develop methods for assessing animal welfare at farm level has grown dramatically since the end of the 1990s, culminating in the protocols developed by the European-wide project Welfare Quality® (WQ). However, these protocols are time consuming and lack transparency in how scores are aggregated into welfare outcomes. The current study investigates the potential of Qualitative Behavior Assessment (QBA), a much less time-consuming approach, to be used as a stand-alone integrative screening tool for identifying farms with compromised welfare before applying the full WQ protocol. QBA is a 'whole-animal' approach asking human observers to summarize animals' expressive demeanor and its context into descriptors such as relaxed, anxious, content or frustrated -terms which given their emotional connotation appear to have direct relevance to animal welfare. Two trained QBA-assessors, and one trained Welfare Quality® assessor visited 43 Danish dairy cattle farms at different times, the former focusing on QBA and the latter making a full WQ protocol assessment. The QBA scores were analyzed using Principal Component Analysis (correlation matrix, no rotation), and WQ protocol data were analyzed and integrated according to the WQ protocol. The resulting QBA and WQ protocol outcomes were correlated using non-parametric methods (Spearman Rank and Kendall W). Highly significant inter-observer agreement was found between the two QBA-assessors (P<0.0001). QBA scores showed some weak correlations to WQ measures but no meaningful pattern of relationship between these measures emerged. The present study does not support the application of QBA as a stand-alone welfare assessment tool capable of predicting the outcome of the larger WQ protocol. © 2012 Elsevier B.V. Source

Desire S.,Animal and Veterinary science Group | Turner S.P.,Animal and Veterinary science Group | D'Eath R.B.,Animal and Veterinary science Group | Doeschl-Wilson A.B.,Roslin Institute | And 2 more authors.
Animal | Year: 2016

Aggression at regrouping is a common issue in pig farming. Skin lesions are genetically and phenotypically correlated with aggression and have been shown to have a significant heritable component. This study predicts the magnitude of reduction in complex aggressive behavioural traits when using lesion numbers on different body regions at two different time points as selection criteria, to identify the optimum skin lesion trait for selection purposes. In total, 1146 pigs were mixed into new social groups, and skin lesions were counted 24 h (SL24h) and 3 weeks (SL3wk) post-mixing, on the anterior, centre and posterior regions of the body. An animal model was used to estimate genetic parameters for skin lesion traits and 14 aggressive behavioural traits. Estimated breeding values (EBVs) and phenotypic values were scaled and standardised to allow direct comparison across multiple traits. Individuals with SL24h and SL3wk EBVs in the least aggressive 10% of the population were compared with the population mean to predict the expected genetic and phenotypic response in aggressive behaviour to selection. At mixing, selection for low anterior lesions was predicted to affect substantially more behavioural traits of aggressiveness than lesions obtained on other body parts, with EBVs between −0.21 and −1.17 SD below the population mean. Individuals with low central SL24h EBVs also had low EBVs for aggressive traits (−0.33 to −0.55). Individuals with high SL3wk EBVs had low EBVs for aggression at mixing (between −0.24 and −0.53 SD below the population mean), although this was predicted to affect fewer traits than selection against SL24h. These results suggest that selection against anterior SL24h would result in the greatest genetic and phenotypic reduction in aggressive behaviour recorded at mixing. Selection for increased SL3wk was predicted to reduce aggression at mixing; however, current understanding about aggressive behaviour under stable social conditions is insufficient to recommend using this trait for selection purposes. © The Animal Consortium 2016 Source

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