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Bovine respiratory disease complex (BRD) causes considerable economic loss and biosecurity cost to the beef industry globally and also results in significant degradation to the welfare of affected animals. The successful treatment of this disease depends on the early, timely and cost effective identification of affected animals. The objective of the present study was to investigate the use of an automated, RFID driven, noninvasive infrared thermography technology to determine BRD in cattle. Sixty-five calves averaging 220 kg were exposed to standard industry practices of transport and auction. The animals were monitored for BRD using conventional biometric signs for clinical scores, core temperatures, haematology, serum cortisol and infrared thermal values over 3 weeks. The data collected demonstrated that true positive animals for BRD based on a gold standard including core temperature, clinical score, white blood cell number and neutrophil/lymphocyte ratio displayed higher peak infrared thermal values of 35.7±0.35 °C compared to true negative animals 34.9±0.22 °C (P<0.01). The study also demonstrated that such biometric data can be non-invasively and automatically collected based on a system developed around the animal's water station. It is concluded that the deployment of such systems in the cattle industry would aid animal managers and practitioners in the identification and management of BRD in cattle populations.

The role of the autonomic nervous system (ANS) in mediating eye temperature responses during painful procedures was examined in thirty 4-mo-old bull calves randomly assigned to 4 treatments: 1) sham handling control (C; n=8), 2) surgical castration (SC; n=6), 3) local anesthesia with sham handling (LAC; n=8), and 4) local anesthesia with surgical castration (LASC; n=8). Maximum eye temperature ( degrees C), measured by infrared thermography, heart rate (HR), and heart rate variability (HRV) were recorded continuously from 25 min before to 20 min after castration. The HRV was analyzed by examining segments of 512 interbeat intervals before and after treatments and comparing the root mean square of successive differences (RMSSD), high and low frequency (HF and LF, respectively) power, and the ratio of LF and HF powers (LF:HF). Jugular blood samples were analyzed for norepinephrine and epinephrine in C and SC treatments and for cortisol during all treatments. There was an immediate increase in HR following castration in SC (+15.3+/-2.8 beats/min) and LASC (+6.3+/-2.4 beats/min) calves. Eye temperature increased during the 20-min observation period in SC and LASC calves (+0.47+/-0.05 degrees C and +0.28+/-0.05 degrees C, respectively), and there was a small increase in C calves (+0.10+/-0.05 degrees C). Following castration in SC calves, there was an increase in RMSSD (+25.8+/-6.4) and HF power (+11.0+/-6.5) and LF:HF decreased (-2.1+/-0.7). Following castration in LASC, there was an increase in RMSSD (+18.1+/-4.9) and a decrease in LF power (-10.2+/-5.0). Cortisol increased above baseline within 15 min following treatment in both castrated groups, but was greater for SC calves (+18.4+/-2.3 ng/mL) than for LASC calves (+11.1+/-1.9 ng/mL). After castration, norepinephrine increased 3-fold and epinephrine increased by half in SC calves but not in C calves. There were no changes in HR, HRV, or cortisol responses to C or LAC treatments. Local anesthetic reduced, but did not eliminate, responses to surgical castration. The synchronized increase in catecholamine and HR responses immediately following SC treatment suggests the initial response was mediated by the sympathetic branch of the ANS. The subsequent changes in RMSSD, HF power, and LF:HF ratio indicated this was followed by an increase in parasympathetic activity. The use of HR, HRV, and infrared thermography measurements together provide a noninvasive means to assess ANS responses as indicators of acute pain in cattle.

Bovine respiratory disease (BRD) complex causes considerable distress to domestic livestock and economic hardship to the beef industry. Furthermore, the resulting extensive use of antimicrobial treatments is a growing concern from the perspective of facilitating antibiotic resistant microbes. The earlier detection of BRD would enable an earlier, more targeted treatment regime and earlier isolation of infected individuals. The objective of the present study was to investigate the use of non-invasive infrared thermography in the early detection of BRD in cattle. Studies were conducted on 133 head of weaned calves. Data demonstrated that infrared thermography was able to identify animals at early stages of illness, often several days to over one week before clinical signs were manifest. Data indicated that 4-6 days prior to the onset of clinical symptoms of BRD, greater positive and negative predictive values and test efficiency for infrared thermography (80%, 65% and 71%, respectively) compared to the industry standard practice of clinical scoring (70%, 45% and 55%, respectively).

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. 1997. Feedlot performance, carcass composition and meat quality of free-range reared pigs. Can. J. Anim. Sci. 77: 225-232. The effects of the housing system (confinement versus free-range) and season (summer versus winter) on growth performance, carcass composition and meat quality were determined from commercial pigs with known NN genotype at the halothane locus. Free-range-housed pigs reared from 25 to 105 kg required 16 ± 1.2 (SEM) more days to reach market weight compared with confinement-housed pigs. Housing did not affect feed requirements during the summer, but food consumption increased by 13.7% for free-range pigs during the winter. Confinement-reared pigs had a 0.75 ± 0.28 kg heavier commercial carcass weight than free-range-reared pigs. While there was no difference in carcass fat thickness, muscle depth was 2.4 ± 1.02 mm greater in free-range-reared pigs with increased predicted lean yield from 59.1 ± 0.24% to 59.8 ± 24%. Free-range-reared pigs had heavier butts, loins and hams, and lighter bellies, which increased their wholesale carcass value by 2.9%. Furthermore, they had greater dissected lean in the picnic (2.0%) butt (4.0%), loin (4.5%) and ham (2.0%) with no compromise to pork quality. If the wholesale price is adjusted for the increased lean content of each cut by an additive or multiplicative model, apparent value was further increased to 5.7 or 8.1%. While these results suggest a beneficial effect on carcass merit when rearing hogs in outdoor facilities, they further suggest potential benefits to carcass grading using developing technologies that recognize differences in carcass conformation. Nous avons étudié sur des porcs d'exploitation commerciale possédant le génotype NN au locus de sensibilité à l'halothane, les effets du système de logement, claustration ou parcours, et de la saison, été ou hiver, sur les performances de croissance, sur la composition de la carcasse et sur les qualités de la viande. Les sujets élevés en parcours à partir du poids de 25 à celui de 105 kg requéraient 16 ± 1,2 (ETM) plus de jours pour atteindre le poids de marché que les porcs élevés en claustration. Le mode de logement ne modifiait pas les besoins alimentaires durant l'été, mais en hiver la consommation augmentait de 13,7 % chez les porcs de parcours. L'élevage en claustration produisait des carcasses de 0,75 ± 0,28 kg plus lourdes que l'élevage en parcours. S'il n'y avait pas de différence relativement à l'épaisseur du gras dorsal, la profondeur du muscle était de 2,4 ± 1,02 mm supérieure chez les porcs de parcours, ce qui, du fait même, relevait le rendement en maigre prédit de 59,1 ± 0,24 % à 59,8 ± 0,24 %. Par ailleurs, le poids plus élevé des socs, des longes et des jambons et la moindre proportion de flancs accroissait de 2,9 % la valeur de carcasse au gros. En outre, les proportions respectives de maigre de dissection dans l'épaule picnic, dans le soc, dans la longe et dans le jambon des sujets éleves en parcours étaient de 2,0, 4,0, 4,5 et 2,0 % plus fortes sans effets négatifs sur la qualité ...