Establishing Bedding Requirements on Trailers Transporting Market Weight Pigs in Warm Weather
Simple Summary Transport is an inevitable process in the modern swine industry. Trailers transporting pigs are bedded with straw, wood shavings, corn stover, or sand. Excess bedding may detrimentally affect the micro-environment inside the trailer during warm weather and in turn negatively affect animal based measures and transport losses. These experiments aim to determine the amount of bedding that is ideal for market weight pig transport during warm weather. Abstract During warm weather, incorrect bedding levels on a trailer transporting market weight pigs may result in heat stress, fatigue, and death. Two experiments were conducted in June and July of 2011; Experiment 1 used 80 loads (n = 13,887 pigs) to determine the effects of two bedding levels (3 (68.1 kg) or 6 bags (136.2 kg) of wood shavings/trailer [each bag contained 22.7 kg, 0.2 m3]) on pig measures (surface temperature, vocalizations, slips and falls, and stress signs). Experiment 2 used 131 loads (n = 22,917 pigs) to determine the effects of bedding (3 vs. 6 bags) on transport losses (dead, sum of dead- and euthanized- on arrival; non-ambulatory, sum of fatigued and injured; total transport losses sum of dead and non-ambulatory). Bedding did not affect surface temperature, vocalizations, or slips and falls (p = 0.58, p = 0.50, and p = 0.28, respectively). However, pigs transported on 6 bags/trailer had 1.5% more stress signs than pigs transported on 3 bags/trailer (p < 0.01). No differences were observed between bedding levels for non-ambulatory, dead, or total transport losses (p = 0.10, p = 0.67, and p = 0.34, respectively). Within the context of these experiments, bedding level did not result in deleterious effects on pig measures or transport losses. However, using more bedding may result in higher costs to the industry. Therefore, 3 bags of bedding/trailer may be used when transporting market weight pigs during warm weather in the Midwestern U.S.
Effects of the Truck Suspension System on Animal Welfare, Carcass and Meat Quality Traits in Pigs
Simple Summary Transportation is a complex stressor in which animals are exposed to a series negatively stimuli, such as vibration, new environmental conditions, variation in temperature and humidity, social mixing, noises among other poor factors, which can result in welfare problems and economic losses such as increased skin lesions, poorer pork quality traits. Transport stress may be reduced through a vehicle suspension system that provides a much smoother ride during transport, and consequently is less aversive to pigs. However, air suspension systems are more expensive and have bigger maintenance costs. This increase in transportation cost must be supported by the benefits from improvements in quality of freight transport; otherwise, the truckers will be paying unnecessarily for a similar or equivalent ride quality. Thus, finishing pigs were assessed after transport to slaughter by the same two double-decked trucks using two types of commercial vehicle suspension, leaf-spring and air suspension, to compare effects on blood cortisol and lactate at exsanguination, behaviour during lairage, and carcass (skin lesions) and pork quality traits. The use of leaf-spring suspension system negatively affects the welfare of pigs due to the increased carcass damage and resulted in poorer pork quality traits. Abstract The objective of this study was to assess the effects of two types of commercial suspension (leaf-spring (LS) vs. air suspension (AS)) installed on two similar double-decked trucks on blood cortisol and lactate concentration, lairage behavior, carcass skin lesions and pork quality traits of 120 crossbred pigs. The suspension type neither influenced pig behaviour in lairage nor blood cortisol and lactate concentrations (p > 0.10). However, when compared with the AS suspension system, the use of LS increased the number of skin lesions in the back and thigh (p = 0.03 and p = 0.01, respectively) and produced thigh with lower pHu (p < 0.001) and yellower colour (higher b* value; p = 0.03), and paler back muscles (subjective colour; p < 0.05), with a tendency to lower pH (p = 0.06). Therefore, the use air suspension system can improve carcass and meat quality traits of pigs transported to slaughter.
Hapten inhibition of passive antidextran dextran anaphylaxis in guinea pigs. Role of molecular size in anaphylactogenicity and precipitability of dextran fractions.
High titred antidextran antisera have been raised in rabbits by prolonged immunization with soluble conjugates between isomaltose oligosaccharides or dextran mw 4,400 and bovine serum albumin in complete Freund’s adjuvant. Guinea pigs sensitized with such antisera exhibited anaphylactic shock on i.v. challenge with fractions of hydrolyzed B512 dextran. The severity of anaphylaxis depended on the amount of sensitizing antibody and the dose and molecular size of the challenging dextran fraction. In maximally sensitized animals, fractions of mw 3,600 or larger were anaphylactogenic and smaller molecular size fractions were nonanaphylactogenic. In submaximally sensitized animals, dextran fractions of mw 10,500 or less were foundnonanaphylactogenic. In addition, nonanaphylactogenic dextran fractions produced desensitization, i.e. protection from anaphylaxis due to subsequent or simultaneous injection of more high molecular and anaphylactogenic dextran fractions. When the molar ratio in a mixture of nonanaphylactogenic/anaphylactogenic fractions was about 7.6, protection was complete with reduction of mortality from 100 to 0%. A molar ratio of 1.9, corresponding to a 13-percent by weight admixture of nonanaphylactogenic dextran, still significantly reduced mortality from 100 to 50%. From the ability to form precipitates with antidextrans and to elicit anaphylaxis in sensitized guinea pigs, and from the absence of these properties, the approximate molecular size range of bivalent and monovalent dextran B512 fractions was found to correspond to mw 3,600 and mw 1,430, respectively. The practical applicability of hapten inhibition is discussed.