Validation of Scan Sampling Techniques for Lactating Sows Kept Outdoors

Scan sampling, observing animals at set intervals is often used by behaviorists to reduce labor inputs which are necessary with continuous sampling. The interval used when scan sampling sows housed outdoors on pasture should take into consideration the desired behavior to be collected. The objective of this study was to validate scan sampling intervals for sow behaviors and postures when sows were housed outdoors on pasture. Validation for the scanning interval was conducted on 23 sows. Sows were scanned every minute between 0730 and 1130 and then again between 1430 and 1830 by one trained observer on one day in May 2001 at the Sustainable Pork Farm. Six behavioral categories were measured; standing, feeding, head down (rooting and grazing), inactive (lying and sitting), drinking and walking. Scan samples could be taken out to as long as 60 minutes or as little as 15 minutes and still obtain accurate data for most behaviors. Validation of scanning intervals based on correlations for walking (0.81 vs. 0.34) and head down (0.98 vs. 0.85) were less (P \u3c 0.01) accurate at 15 min scan than when a 1-min interval was used. When LSMeans were compared, standing, head and walking became less accurate (P \u3c 0.05) at a 30 min scan compared to the 1 min scan control. For inactive behaviors there was no differences from 1 min scans until a 60 min scan (P = 0.03). In conclusion, when the period of scanning was shorter, a more precise prediction of behavior and postures was obtained. However, a balance must be struck between practical feasibility and accuracy when conducting 24 hours of behavioral observations in the field

Effects of shaded versus unshaded wallows on behavior, performance, and physiology of the outdoor lactating sow

The objectives of this study were to determine the effects of shading wallows during the summer months on lactating sow behavior, performance, and physiology. A total of 128 sows were used during warm weather (May to August 2001) to determine the effects of unshaded (control; n = 8) vs. shaded (SH; n = 8) wallows. Sows ranged over 6 parities and were fed a completely balanced sorghum-based diet. Behavioral data were collected by 15-min scan samples over a 24-h period/wk for a total of 16 wk. All sows were observed twice when litter age was 5 and 15 d, respectively. Respiration rates (breaths/min) were collected on 50 sows (control, n = 25; SH, n = 25) over an 8-wk period when the maximum temperature exceeded 32°C. Ten milliliters of clotted blood and 20 mL of whole blood were obtained by jugular puncture from each sow on the day of weaning to determine total white blood cells, acute phase proteins, packed-cell volume, and chemotaxis and chemokinesis. Descriptive water temperature profiles were measured by using data loggers positioned at 3 levels per wallow: surface water, shallow mud, and deep mud. Behavioral, postural, location, performance, and physiological measurements did not differ (P \u3e 0.05) among wallow treatments. Regardless of treatment, sows spent approximately 82% of their total time budget inside the farrowing hut and only approximately 7% of their total time budget in the wallow. A total of 428 piglets died, 219 in the control treatment and 209 in the SH treatment. The majority of piglets in both treatments died of crushing within the first 72 h after parturition, and most of the piglets had suckled. Shade kept the shallow water profile cooler during the hotter afternoon temperatures compared with the control wallows. In SH for both the shallow and deep mud profiles, temperatures were consistent throughout the day. In conclusion, sows spent a large percentage of their daily time budget inside the farrowing hut and spent only brief episodes in the wallow. Shading the wallow did not result in increased wallow use time or improvements in sow physiology and overall performance

Preweaning mortality in loose-housed lactating sows: Behavioral and performance differences between sows who crush or do not crush piglets

The majority of piglet deaths occur within the first 72 h after parturition, with crushing by the sow as the most common cause of preweaning mortality. The aim of this study was to compare the behavior and performance of sows that killed piglets (CR) to those that did not (NC) inside a farrowing hut within the first 72 h after parturition. A total of 336 sows and their litters were used for comparisons. CR sows had more (P \u3c 0.01) piglets born/litter and born alive/litter than NC sows. Mortality was higher (P \u3c 0.01) for CR sows, with most piglet mortality in the first 72 h and there was a trend (P = 0.06) for CR sows to wean fewer piglets/litter than NC sows (7.8 ± 0.20 versus 8.4 ± 0.26), respectively. Behaviors were collected by time-lapse video on 20 sows, 10 from each group. Four sow postures: walking, standing, sitting and lying; four sow behaviors: pawing, rooting, nursing interval and nursing duration; and one sow location: out of hut were recorded. NC sows had a longer (P = 0.03) parturition compared to CR sows. Time (min) spent outside the farrowing hut did not differ between groups over the first 2 days, but on day 3 NC sows spent more (P = 0.01) time outside of the farrowing hut (20.2 ± 4.7) compared to CR sows (40.4 ± 4.8). NC sows spent more time pawing (P \u3c 0.01) than CR sows (5.2 ± 0.41 min versus 1.7 ± 0.38 min) but no differences were found for all other behaviors (P \u3e 0.05). There were no (P \u3e 0.05) group differences for sow lying postures. One hour prior to piglet mortality 62.5% of CR sows moved from lying sternal to lying lateral, 25% moved from lying lateral to lying sternal and 12.5% of CR sows went from standing to lying lateral. In conclusion, CR sows spent more time inside the farrowing hut on day 3, spent more time lying on their sternum prior to crushing a piglet and the behavioral sequence associated with crushing piglets was a shift in lying postures rather than a transition from sitting or standing to lying

Establishing Trailer Ventilation (Boarding) Requirements for Finishing Pigs during Transport

Specifically, this study aimed to establish the effects on mortality and morbidity of boarding levels (amount of side-wall trailer ventilation) for finishing pigs in mild weather (8.80 ± 0.30 °C, 71.70% ± 1.12% humidity). Pigs from commercial finishing sites were transported in 302 pot-bellied trailers to commercial processing plants. Measures collected at the processing plant were rates of dead on arrival (DOA), non-ambulatory, non-injured (NANI), non-ambulatory, injured (NAI), and total dead and down (D&D). Boarding levels (% that side walls were closed off with inserted boards) were divided into 3 bins: low, medium, and high, and outside temperature was divided into 4 bins \u3c5 °C, 5.10–10 °C, and 10.10–15 °C and \u3e15 °C. Average rates of DOA, NANI, NAI, and D&D were approximately 0.30%, 0.12%, 0.04%, and 0.46%, respectively. The D&D was highest when boarding level was low with temperatures \u3c5 °C (p \u3c 0.05). However, variations in boarding level (medium and high boarding) in the temperature range of 5.10 °C to 23.30 °C did not affect pig losses

Thermally-stable amorphous metal thin films

Amorphous metal thin films (AMTFs) are of potential use for metal-insulator-metal (MIM) tunnel diode applications due to their ultra-smooth surfaces, a consequence of their amorphous microstructure. The objective of this thesis is to design a thermally-stable AMTF capable of maintaining MIM tunnel diode performance after a post-deposition anneal in excess of 500 °C. The following guidelines are employed in the design of a thermally-stable AMTF: (i) The amorphous metal should be composed of three or more elements with the highest concentration being a refractory metal. (ii) Constituent elements should have a wide distribution of atomic radii, with at least a 12% difference in size between any two elements. (iii) A large negative heat of mixing should exist among elemental constituents. (iv) At least one constituent element should be a metalloid, such as Si. Using these guidelines three AMTFs - TaNiSi, TaMoSi, and TaWSi- are investigated and are found to be thermally-stable to the extent that their crystallization temperature is greater than 600 °C. TaWSi is found to have the highest crystallization temperature, i.e., ∼ 1000 > 900 °C, and is used in the fabrication of a thermally-stable MIM diode which exhibits Fowler-Nordheim dominated tunneling even after being subjected to a post-deposition anneal at 525 °C

Establishing Bedding Requirements during Transport and Monitoring Skin Temperature during Cold and Mild Seasons after Transport for Finishing Pigs

The broad aim of this study was to determine whether bedding level in the transport trailer influenced pig performance and welfare. Specifically, the objective was to define the bedding requirements of pigs during transportation in commercial settings during cold and mild weather. Animals (n = 112,078 pigs on 572 trailers) used were raised in commercial finishing sites and transported in trailers to commercial processing plants. Dead on arrival (DOA), non-ambulatory (NA), and total dead and down (D&D) data were collected and skin surface temperatures of the pigs were measured by infrared thermography. Data were collected during winter (Experiment 1) and fall/spring (Experiment 2). Total D&D percent showed no interaction between bedding level and outside air temperature in any experiments. Average skin surface temperature during unloading increased with outside air temperature linearly in both experiments (P \u3c 0.01). In conclusion, over-use of bedding may be economically inefficient. Pig skin surface temperature could be a useful measure of pig welfare during or after transport

Derivation and validation of murine histologic alterations resembling asthma, with two proposed histologic grade parameters

<p>Abstract</p> <p>Background</p> <p>The objective was to define murine histologic alterations resembling asthma in a BALB/c OVA model and to suggest grading criteria. Identified were six salient histologic findings in lungs with putative allergic inflammation: 1) bronchoarterial space inflammation; 2) peri-venular inflammation; 3) inflammation about amuscular blood vessels; 4) inter-alveolar space inflammation, not about capillaries; 5) pleural inflammation; and 6) eosinophils within the inflammatory aggregates. An initial study comprised six groups of twelve mice each: 1) stressed, control; 2) stressed, sensitized; 3) stressed, challenged; 4) not physically stressed, control; 5) not physically stressed, sensitized; 6) not physically stressed, challenged. A second study comprised four experimental groups of twenty mice each: 1) stressed, control; 2) stressed, challenged; 3) not physically stressed, control; 4) not physically stressed, challenged. A third study evaluated two grading criteria, 1) the proportion of non-tracheal respiratory passages with inflammatory aggregates and 2) mitoses in the largest two non-tracheal respiratory passages, in five groups of five mice each, evaluated at different times after the last exposure.</p> <p>Results</p> <p>The first study suggested the six histological findings might reliably indicate the presence of alterations resembling asthma: whereas 82.4% of mice with a complete response had detectable interleukin (IL)-5, only 3.8% of mice without one did; whereas 77.8% of mice with a complete response were challenged mice, only 6.7% of mice without complete responses were. The second study revealed that the six histological findings provided a definition that was 97.4% sensitive and 100% specific. The third study found that the odds of a bronchial passage's having inflammation declined 1) when mitoses were present (OR = 0.73, 0.60 - 0.90), and 2) with one day increased time (OR = 0.75, 0.65 - 0.86).</p> <p>Conclusion</p> <p>A definition of murine histologic alterations resembling asthma in the BALB/c OVA mouse was developed and validated. The definition will be of use in experiments involving this model to ensure that all mice said to have undergone an asthmatic attack did indeed reveal allergic pulmonary inflammation. Proposed grading criteria should be further evaluated with additional studies using physiologic measures of attack severity and increased airway resistance.</p