The objective of this study was to determine the effect of trucking of Porcine Stress Syndrome (PSS) heterozygous (Nn)- and homozygous-negative (NN) pigs under a hot environmental temperature (30°C and 36°C). Rectal temperature, respiratory rate, and levels of serum glucose, lactic acid, thyroxine and cortisol before and after transportation were determined in each pig. Rectal temperatures of Nn and NN pigs gained significantly (P<0.05) at the loading than before transport. During transportation, rectal temperatures of Nn pigs were higher (P<0.01) than those of NN pigs on the 36°C-loading truck, whereas on the 30°C-loading truck, they were not different. Before the transportation, respiratory rates of Nn pigs tended to be higher than those of NN pigs in either of the thermal conditions, 30°C or 36°C. Serum glucose increased after transportation in both genotypes (P<0.05). Serum lactic acid was not affected by loading pigs on the truck. In contrast, Serum thyroxine and cortisol levels increased significantly after the transportation (P<0.05 and P<0.01, respectively). The gain of rectal temperature indicated that pigs were suffering from a severe stress by being loaded on to truck in a hot environment. The present study suggests that the response of pigs to the transportation is dependent on genotype, particularly at 36°C.

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The objective of this study was to examine the effects of reactive oxygen species (ROS) produced by a xanthine (X)-xanthine oxidase (XO) generating system on the motility of boar spermatozoa in the process of freezing-thawing, and to evaluate the ability of the antioxidants to protect sperm from this challenge.
The sperm rich fraction was diluted with the pre-diluent and stored for 3hrs at room temperature, and then divided into 6 tubes before centrifugation. Precipitated sperm in each tube was suspended in one of the following lactose-egg yolk diluents added antioxidants. 1) Lactose-egg yolk (control), 2) X (0.6mM)-XO (0.05U/ml), 3) X-XO and catalase (Cat) (150U/ml), 4) X-XO and super oxide dismutase (SOD) (150U/ML), 5) X-XO and glutathione (GSSG) (1.5mM) or 6) X-XO and hypotaurine (HT) (10mM). Each group of sperm was cooled to 5°C and then added the 2nd diluent including glycerol and OEP. Finally diluted semen was packaged in the maxi-straw and then frozen in liquid nitrogen vapor. It took about 2hrs from the exposure of ROS to freeze.
After the semen was thawed at 45°C, it was diluted with the thawing-diluent and incubated at 37°C for 60 minutes to observe the motility. The results were expressed as the mean±S. E. of 9 ejaculates from 3 boars.
Frozen-thawed sperm with X-XO alone was significantly low in revival rate in incubation compared to the control group. The revival rate of the X-XO and catalase group in incubation was significantly high compared to that of the X-XO alone group. Also high revival rates were obtained in both groups of X-XO and SOD, and X-XO and hypotaurine after incubation showed significantly high values in the sperm with X-XO and catalase, and with X-XO and hypotaurine compared to that of the X-XO alone group.
These results indicate that ROS adversely affect motility in the process of freezing and thawing of boar sperm. Catalase completely inhibited the decline of motility in the presence of X-XO indicating that hydrogen peroxide is the primary ROS affecting sperm motility. Hypotaurine is also valuable to inhibit adverse effect of ROS.

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We investigated the effect of the motility of frozen-thawed boar semen on the conception rate and the number of fetuses. Semen used in this experiment was collected from 12 boars in the 4th generation of selection experiment for Duroc pig at Miyagi Prefecture Animal Industry Experimental Station. Boar semen was treated by the current method and samples were frozen using a programed freezer. The diluent was changed to modena. We conducted artificial insemination (AI) using frozen-thawed boar semen which had different motility. And sows were slaughtered to count the number of fetuses 28-44 days (avg. 33.7±5.5 days) later after AI. While the conception rate and the number of fetuses were 58.3% and 6.4 in the case of the low motility (45-55%) frozen-thawed boar semen, those were 91.7% and 9.4 in high motility (70-80%) frozen-thawed boar semen. The results suggested the possibility that the conception rate and the number of fetuses were improved by using high motility (70-80%) frozen-thawed boar semen. The conception rate and average litter size in field conception experiment by using frozen-thawed boar semen of high motility (60% or more) were 46.2% and 7.8, respectively.

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