PubMed Health⌕ Search

Biomedical subjects

A Kunavongkrit

Publications and source records attributed to A Kunavongkrit.

18 recordsLinked to original sources
PubMed1992

Comparison of virus isolation, immunofluorescence and DNA probe hybridization for detection of pseudorabies virus in experimentally infected pigs.

Virus isolation, immunofluorescent staining and DNA probe hybridization, three techniques for the detection of pseudorabies virus (PRV) have been compared in pigs experimentally infected with the Thailand CB-1 strain PRV. The virus isolation and DNA hybridization detection demonstrated a good correlation in detecting infection in live animals by nasal swabbing. In white blood cells an earlier detection was seen with the DNA-hybridization techniques. Consistent results with all the three techniques tested were found in organ materials as nasal mucosa and tonsils as well as in the olfactory bulb.

Animals↗
PubMed1987

Increase of insulin and decrease of glucagon levels in response to total and fractionated weaning in sows.

The effect of weaning on plasma levels of insulin and glucagon as well as on plasma glucose levels was studied in sows after final weaning (all the piglets removed in week 5 of lactation) and fractionated weaning (7 out of 12 piglets removed in week 3 of lactation). Insulin levels rose from 24 +/- 6 to 106 +/- 22 microU ml-1 4 days after final weaning and from 11 +/- 1 to 128 +/- 20 microU ml-1 7 days after fractionated weaning. Glucagon levels fell from 60 +/- 20 and 42 +/- 8 to 35 +/- 10 and 24 +/- 5 pm in the two groups, respectively. Plasma glucose levels increased from 4.5 +/- 0.5 to 7.2 +/- 1.2 mM after fractionated weaning and remained unchanged after final weaning. One possible mechanism that can explain this pronounced insulin increase and decrease of glucagon is the elevation of plasma glucose, since milk is no longer emptied from the mammary gland and since insulin resistance occurs after weaning in rats. Another possible explanation could be a decreased number of insulin receptors in the mammary gland, since prolactin which is known to increase insulin receptors is decreased in weaned rats.

Animals↗
PubMed1986

Investigation into the use of prostaglandin F2 alpha (PGF2 alpha) and oxytocin for the induction of farrowing.

This experiment was conducted in order to compare the effects of injecting PGF2 alpha alone, PGF2 alpha with oxytocin and placebo on the induction of farrowing in swine and to compare the relative effects of 3 different dosages of oxytocin (10, 20 and 30 iu per animal) when combined with PGF2 alpha (10 mg). The findings revealed that animals treated with 30 iu oxytocin farrowed within 10.6 h which was similar to those receiving PGF2 alpha only (9.4 h), but shorter than control animals (53.6 h). Animals receiving 20 and 10 iu of oxytocin farrowed within 1.4 and 1.7 h, respectively. Difficult farrowings requiring manual assistance occurred in 30%, 30%, 50% and 10% of sows given 30 iu, 20 iu and 10 iu of oxytocin and in the control group, respectively. Thirteen of 73 sows treated with PGF2 alpha farrowed within 12.6 +/- 5.3 h. Stillbirths were highest (10.2%) in the control animals whilst in the others it was under 7%. Oxytocin at dosages of 20 and 10 iu, seemed most promising in terms of synchronising farrowing following PGF2 alpha treatment in swine. However, farrowing complications were more common in these groups.

Animals↗
PubMed1985

Plasma levels of oxytocin increase in response to suckling and feeding in dogs and sows.

The objective of the present study was to investigate whether oxytocin is released in response to feeding in analogy to the response induced by suckling. Therefore, repeated plasma samples were drawn from dogs and pigs during feeding and suckling and oxytocin levels were determined by radioimmunoassay. As expected suckling gave rise to immediate and short-lasting increases of oxytocin levels in both species. More surprisingly, feeding in female and male dogs as well as in lactating sows was accompanied by a similar-sized rise of oxytocin levels. The oxytocin peak sometimes occurred before the actual period of suckling or feeding, suggesting that the output of oxytocin had been conditioned to visual, olfactory or auditory stimuli associated with both types of situations. It is well known that oxytocin is released in lactating animals in response to touching of the teats. It is possible that also the presence of food in the gastro-intestinal tract activates neurogenic mechanisms which stimulates the release of oxytocin. Since oxytocin causes a release of insulin and VIP (vasoactive intestinal polypeptide), peptides which appear in the circulation following both suckling and feeding, it is suggested that oxytocin may be involved in the control of the suckling- and feeding-related output of these peptides.

Animals↗
PubMed1984

Influence of suckling and feeding on insulin, gastrin, somatostatin and VIP levels in peripheral venous blood of lactating sows.

Blood samples were collected in peripheral venous blood of seven lactating sows, when their piglets were suckling. In four of the experiments samples were also taken when the sows were fed a meal. Gastrin, insulin, somatostatin and VIP levels were measured by radioimmunoassay. Insulin levels increased by approximately 100% for about 10 min in response to suckling, in some experiments even before the suckling occurred, i.e. when the sows saw, heard and smelled their piglets. In four of the sows suckling caused a biphasic twofold increase in gastrin levels - one immediate peak which lasted for a few min and a second peak of longer duration (about 30-60 min), whereas gastrin levels remained unchanged in three animals. Somatostatin levels usually reflected gastrin levels in a reciprocal way. Thus, a biphasic decrease of somatostatin levels occurred in the high gastrin responders. In contrast, somatostatin levels increased in the experiments, in which gastrin levels did not change. Immediate and short-lasting (a few minutes long) increases of VIP levels were also induced by suckling. Large litters and long suckling periods appeared to be related to greater changes of the levels of all the peptides measured. Feeding influenced insulin, gastrin and somatostatin levels in the same way as did suckling from both a qualitative and a quantitative point of view. In contrast, VIP levels were not increased by feeding. The possible functional effects of the suckling-induced release of gastrointestinal hormones and possible mechanisms of their release are discussed.

Animals↗
PubMed1984

Laparoscopy in post partum sows with special emphasis on the effects of uterine manipulation on the release of prostaglandin F2 alpha.

One hundred laparoscopies were performed on 30 primiparous post partum sows and complications during and after examinations recorded. Nineteen of these animals were separated into two groups and subjected to different treatments: group 1 (10 sows), with conventional laparoscopy; group 2 (nine sows) with two minutes extra manipulation of the uterus after laparoscopy. Blood was sampled before and after the operations. The plasma was analysed for its content of 15-keto-13,14-dihydroprostaglandin F2 alpha by radioimmunoassay. The results indicate that laparoscopies were successful and can be used in post partum sows during lactation and after weaning without any severe complications. In some sows laparoscopy alone or laparoscopy followed by manipulation of the uterus for two minutes caused a peak of the prostaglandin metabolite. However the height and duration of this peak were not sufficient to influence reproductive performance in pigs.

Animals↗
PubMedDate not supplied

Ovulation rate and embryonic migration in cross-bred gilts.

The object of the investigation was to compare the activity between left and right ovaries in gilts slaughtered after their 1st, 2nd, 3rd or 4th detected oestrus and to relate the incidence of embryonic migration to the total number of foetuses present. The study comprised 254 cross bred gilts (Swedish Landrace X Swedish Yorkshire) not returning to oestrus within 24 days after A.I. with frozen semen. The gilts were slaughtered 5-8 weeks after A.I. The genital tracts were examined within two hours after slaughter. The number of corpora lutea and the number of normally developed foetuses were recorded. The results indicated that the left ovary had a higher ovulation rate than the right (P less than 0.001). The left ovary was also heavier than the right (0.01 less than P less than 0.05). The number of corpora lutea increased from oestrous number 2 to 4 (2 vs 4, 3 vs 4, 0.01 less than p less than 0.05). The oestrous number did not significantly influence the fertilization rate. The incidence of embryonic migration increased with increasing number of foetuses (0.01 less than p less than 0.05). Migration from left to right and from right to left occurred with the same frequencies.

Animals↗