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Title ANALYSIS RELATING TO CORPORA LUTEA AND TWO CONTINUOU BEEF CATTLE Author(s)KANAGAWA, Hiroshi; ISHIKAWA, Tsune CitationJapanese Journal of Veterinary Research, 28(4): 105- Issue Date 1981-01-31 DOI 10.14943/jjvr.28.4.105 Doc URL http://hdl.handle.net/2115/2203 Type bulletin File Information KJ00002374012.pdf Instructions for use Hokkaido University Collection of Scholarly and Aca

Jpn. J. Vet. Res., 28, 105-113 (1980) ANAL YSIS RELATING TO CORPORA LUTEA AND TWO CONTINUOUS ADMINISTRATIONS OF PMSG IN BEEF CATTLE Hiroshi KANAGAWA and Tsune ISHIKAWA Department of Veteri!lal'V Obstetrics Faculty of Veterinary l\edicine Hokkaido Uni'cersity, Sapporo 060, Japan (Received for publication, June 5, 1980) One hundred and eight beef cattle were divided into 2 groups of 54 cattle each. The 1st group was administered 2,000 IV of pregnant mare's serum gonadotrophin (PMSG) for the first treatment, and the same dose of PMSG was applied for the second treatment 54-257 days later. The 2nd group of 54 cattle received 1,600-2,500 IU of PMSG for the first treatment and a dose increase ranging from 100 to 1,000IU for the second treatment 36-206 days later. Both groups received the PMSG on Days 9-14 (estrus as Day 0), and 2 days after the administration of PMSG, 25 mg of prostaglandin F 2 a was injected intramuscularly. Two days after the prostaglandin F 2 a treatment, estrus detection was performed and the cattle were inseminated artificially. The animals were operated at midline under general anaesthesia at 5-7 days after estrus, and a number of corpora lutea were observed in situ. In the 54 cattle of the 1st group, the average number of corpora lutea was 15.6 after the first PMSG treatment, and 11.3 after the second. In the 2nd group, 13 cattle received a dose increase of 100-400 IV of PMSG for the second treatment, which resulted in the average number of 12.0 corpora lutea after the first PMSG treatment, and 8.3 after the second. Furthermore, 31 cattle received a dose increase of 500-750IU of PMSG for the second treatment, resulting in an average number of 6.6 corpora lutea after the first treatment, and 8.5 after the second. Finally, 10 cattle received a dose increase of 1,000IU of PMSG for the second treatment, which resulted in an average number of 6.5 corpora lutea after the first treatment, and 10.7 after the second. INTRODUCTION The transfer of fertilized embryos from one animal to another has long been considered a useful research tool among researchers in the field of animal reproduction. In recent years, the application of embryo transfer techniques to cattle has aroused interest in several countries. transfers. There are several technical difficulties of procedure in embryo Among these difficulties, reliable superovulation has been regarded as one of the most important factor. Many researchers have reported wide variations in individual ovarian responses and in the amount of ovulation in cattle after injections with

106 KANAGAWA, H. & ISHIKAWA, T. a standard dose of PMSG (ROWSON, '51 ; GORDON et ai., '62; HAFEZ et ai., '63 ;SCANLON et ai., '68; MAULEON et ai., '70; GORDON, '75). repeated in the following estrus cycles, it was ineffective. However, if PMSG administration was These results were in accord with the findings of WILLETT et ai. ('53) and other cattle researchers (HAFEZ et ai., '65; SAUMANDE & CHUPIN, '77). It has been suggested that gonadotrophins similar to PMSG simulated antigens which induced the formation of antibodies when injected into animals (NAKAHARA et al., '64; SCHAMS et al., '78). This reduction in ovulation after PMSG treatments IS an important factor in embryo transter when repeated treatments are needed. In this paper we report the results of an analysis relating to corpora lutea and 2 continuous administrations of PMSG in beef cattle. MATERIALS AND METHODS One hundred and eight cattle consisting of 46 Simmental, 25 Charolais, 20 Limousin and 17 other beef breeds were used. Ninety-two out of 108 cattle were heifers, and the remaining 16 were cows. The 108 beef cattle were used as shown in table 1; all demonstrated normal reproductive tracts as determined by rectal examination. For the first PMSG treatment, each animal was given a single intramuscular injection of 1,600-2,500IU of PMSG at Days 9-14 after estrus (estrus as Day 0), which was followed 48 hours later with intramuscular injections of 25 mg of prostaglandin F2IX or its analogue. The animals were then inseminated 2-3 times with frozen semen at 12 hour intervals during estrus (fig. 1). As shown in table 1, 4 different brands of PMSG from 4 companies, which were divided into 2 groups, were used in this study. The 1st group consisted of the same dose of PMSG (2,000 10) for the first and second treatment, while the 2nd consisted of dose increases ranging from 100-1,00010 of PMSG between the first (1,600-2,50010) and second (2,000-3,00010) treatments (tab. 2). On Days 5-7, following estrus and 48 hours fasting, the animals were anaesthetized, TABLE 1 PNISG used in this study PMSG First TREATMENT Second REMARKS* A 65 41 34 B 36 55 30 C 5 2 D 2 10 Total 108 108 * Same combination of PMSG between first and second treatments

Corpora lutea after P1HSG in cattle 107 TABLE 2 PlvISG doses and interval bet'lc'een first and second treattllents GROUP NUMBER OF ANIMALS EXAMINED PMSG TREATMENTS First Second INTERVALS I ]I Total 54 2,000IU 2,000IU 54-257 days 1,600 2,000 54 36-206 2,500 3,000 1,600 2,000 108 36-257 2,500 3,000 Previous estrus FIGURE 1 Previous estrus Procedure for PlvlSG tn:atment PMSG Induced Laparotomy & PGF 2 a estrus observation o 20 (days) o 5 10 15 20 (days) and the corpora lutea of each were examined via midventrallaparotomies. The number of corpora lutea in the two ovaries was then recorded. After the initial PMSG treatment, most of the animals were allowed at least two or more estruses, which occurred spontaneously. Each animal was given a second PMSG treatment between Days 9 and 14 in precisely the same manner as in the initial treatment. RESULTS Out of the 108 cattle, 98 of the animals which received 2,000IU of PMSG for the first treatment were selected for statistical analysis (fig. 2). The average number of corpora lutea differed significantly between the Simmental and the Limousin breeds (P < 0.05). As shown In table 3, the same batches and doses of PMSG were selected for both the first and second treatments. The number of corpora lutea after the second treatment was lower than that of the first treatment in all breeds. Table 4 shows the average number of corpora lutea among the 4 sub-groups of PMSG dosages. In sub-groups 1 and 2, the same dose, or an increased dose of PMSG for the second treatment, revealed a decreased number of corpora lutea, however, in sub-groups 3 and 4, an increase of 500-1,000 IV of PMSG for the 2nd treatment showed

108 KANAGAWA, H. & ISHIKAWA, T. FIGURE 2 Comparison of the number of corpora lutea for all breeds after the first treatment of PlvfSG*l NS * Simmental NS N=44 CL=10.2 Charolais NS NS N=22 CL=12.0 Limousin NS N=17 CL=15,4 Others N=15 CL=12.5 *1 Ninety-eight of the 108 cattle selected to receive 2,000 IU of PMSG for the first treatment were used for the analysis. NS Not significant * Significant (P<0.05) CL Average number of corpora lutea TABLE 3 A-verage number of corpora lutea between first and second PMSG treatments for all breeds*l BREEDS PARITY NUMBER OF ANIMALS EXAMINED First treatment A VERAGE NUMBER OF CORPORA LUTEA Second treatment Difference Simmental Charolais Limousin Others*2 11 13.1 7 16.1 5 23.4 6 16.2 8.9-4.2 9.0-7.1 19.5-3.9 14.0-2.2 Subtotal 29 17.2 12.9-4.3 -------- Mixed*3 Cows 5 13.8 11.2-2.6 Total and cows 34 16.5 12.5-4.0 *1 Out of the 108 animals, the 34 which had the same dose and source of PMSG for both the first and second treatments were selected for this table. *2 Including 2 Maine-Anjou, 2 Blonde d'aquitaine, 1 Murray Grey and 1 Chianina breeds *3 Including 2 Charolais, 2 Simmental and 1 Limousin breeds

GROUP TABLE 4 Number of corpora lutea and animals between first and second treatments A VERAGE NUMBER OF NUMBER OF ANIMALS FOR INCREASED NUMBER OF CORPORA L UTE A SECOND TREATMENT --. --------------- SUB-GROUP DOSE OF PMSG ANIMALS r'yifference FOR SECOND EXAMINED First Second Increased Same Decreased after second TREATMENT treatment treatment CL CL CL treatment () I 1 o IU 54 15.6 11.3-4.3 (42.0) 13 1 40 2 100-400 13 12.0 8.3-3.7 (40.9) 3 0 10 l[ 3 500 30 6.8 8.5 +1.7 (55.6) 17 1 12 4 750-1,000 11 6.5 10.7 +4.2 (48.7) 8 1 2 Total 108 10.2 9.7-0.5 (48.7) 41 3 64 CL: Corpora lutea TABLE 5 Relation bet'lc'cen inter'l'al and number of corpora l!ltea NUMBER OF ANIMALS AT A VERAGE NUMBER OF CORPORA LUTE A INTERV AL BET\tVEEN NUMBER OF SECOND TREATMENT FIRST AND SECOND ANIMALS First Second Increased Same Decreased TREATMENTS EXAMINED* Difference Second/First treatment treatment CL CL CL 54-66 days 9 14.5 8.1-6.4 5.9% 1 0 8 70-79 9 15.4 17.6 +1.2 114.3 3 0 6 80-- 87 11 17.1 12.5-4.6 73.1 4 0 7 90-98 7 17.4 10.1-7.3 58.0 1 1 5 102-257 18 14.3 9.7-4.6 67.8 3 0 15 ------_.. Total 54 15.6 11.3-4.3 72.4 12 1 41 * Out of the 108 animals, the 54 which received the same dose of PMSG (2,000 IU) for both the first and second treatments were selected for this table. ('"\ :::l < :::l... :;:: "".,<,. "'\ \:),... ""... "" N \0

------ 110 KANAGA W A, H. & ISHIKAWA, T FIGURE 3 Statistical analysis het'ween PlvISG dose and number of corpora lutea I (OIU) * * NS N=54 42.0% 11 (100-400 IU) * NS N=13 40.9% n (500IU) NS N=30 n(750-1,000 IU) N=l1 66.2% 55.6% * NS % IU Significant (P < 0.05) Not significant Increase of corpora lute a after second treatment Increased dose of PMSG for second treatment TABLE 6 Statistical analysis*1 of corpora lutea between first and second P]!'lSG treatments of Simmental cattle PMSG DOSE NUMBER OF GROUP BREEDS FOR SECOND TREATMENT INTERVAL ANIMALS EXAMINED I Simmental Same 54-79 days 6 IT Simmental Same 80-174 14 IT Simmental Increased 36-156 26 RESULTS - ---- * NS NS *1 * NS x 2 test on corpora lutea between first and second treatments Significant (P < 0.05) Not significant an increased number of corpora lutea. Figure 3 provides an evidence that a dosage of between 400 and 500 IU of PMSG had an effect on the proportion of corpora lutea. The relation between the administration intervals and the average number of corpora lutea is shown in table 5. The number of corpora lutea increased slightly at 70-79 days, however, there was no significant difference between this interval and the average number of corpora lutea. The Simmental breed was selected in order to examine the difference in the number of corpora lutea between the first and second treatments by the x 2 test. Table 6 shows that there was a significant difference between the first and second treatments when

Corpora lut('a after Pl11SG in cattle 111 the interval between the two treatments was 54-79 days (P<0.05), however, there was no significant difference when the interval was 80-174 days, nor was there any difference when the dose was increased during the 36-156 days interval. DISCUSSION The ability of PMSG to induce multiple ovulations has led to the wide scale use of the hormone for stimulating superovulation for the purpose of embryo transfer in cattle. A reduced ovulation rate in cattle given repeated PMSG administrations has been recorded by several researchers (HAFEZ et ai., '65; SAUMANDE & CHUPIN, '77). It has been suggested that PMSG simulates antigens which induce the formation of antibodies, however, NEWCOMB et ai. (,79) have suggested that antibodies to PMSG are unlikely to be formed when normal levels of PMSG are administered to cattle, and that it is also unlikely that the high steroid levels which appear after the first PMSG treatment impaire follicle development. In this study we observed the expected reduction of corpora lutea at the second treatment of PMSG, however, a dose increase of 500 IV or more of PMSG did not affect their reduction. To explain the reduction of ovarian response to repeated PMSG treatments, some investigators have put forth the possibility that antibodies to PMSG are formed (NAKAHARA et al., '64; SCHAMS et ai., '78). The possibility also exists that the reduced response to repeated treatments is attributable to individual immunity to either the FSH or to the LH moieties of PMSG, since PMSG contains both FSH and LH biological activities. NEWCOMB et al. ('79) have reported the significant effect of PMSG doses (1,000 and 2,000IU) after the second treatment, although they did not show evidence that the ovarian response was affected by the PMSG batch used. In this study, there was a significant difference when the PMSG dose was increased by 500IU or more, however, our standard PMSG dose was approximately 2,000IU, and there was no significant difference when the dose was increased by 100-40010. Reduction of the ovarian response of cattle to repeated superovulation treatments has been recorded by several authors (HAFEZ et ai., '65; SAUMANDE & CHUPIN, '77;. It is well known that the dosage and the interval between the two PMSG treatments are important factors. In general, immunological antibodies in animals are reduced by a titer or disappear completely after certain periods. NAKAHARA et al. (,61) have reported that anti-pmsg was negative 100 days after the PMSG injection. It has been suggested that the injection of exogenous gonadotrophin may result in the temporary loss of specific hormone receptors. The repeated treatment of beef cattle with PMSG in this study indicated that a dose increase of 500 10 or more for the second PMSG treatment had a significant effect, and that an interval of 70 days or more from the first treatment was effective. There was no increase in the number of corpora lutea when 100-

112 KANAGAWA, H. & ISHIKAWA, T. 400 IU of PMSG were injected and less than 70 days had expired before the second PMSG treatment. ACKNOWLEDGEMENTS A part of this study was performed at the laboratory of Modern Ova Trends Limited, Ontario, Canada. The statistical analysis was carried out at Hokkaido University Computing Center. This work was supported in part by a Grant-in-Aid from the Ministry of Education, Culture and Science, Japan. We thank Miss F. KURODA for the preparation of the manuscript. REFERENCES 1) GORON, 1. (1975): Problems and prospects in cattle egg transfer Irish Vet. J., 29, 21-62 2) GORDON, 1., WILLIAMS, G. & EDWARDS, J. (1962): The use of serum gonadotrophin (PMS) in the induction of twin-pregnancy in the cow J. Agric. Sci., 54, 143-200 3) HAFEZ, E. S. E., JAINUDEEN, M. & LINDSAY, D. R. (1965): Gonadotropin-induced twinning and related phenomena in beef cattle Acta Endocrinol., Suppl. 102, 5-43 4) HAFEZ, E. S. E., SUGIE, T. & HUNT, W. L. (1963): Superovulation and related phenomena in the beef cow 1I Effect of oestrogen administration on production of ova J. Rep rod. Ferti!., 5, 381-338 5) MAULEON, P., MARIANA, J.-C., BENOIT, M., SOLARI, A. & CHUPIN, D. (1970): The effect of different PMSG and HCG doses injected during the follicular phase of the oestrous cycle on the number and yield of ovulations in French Friesian cattle Ann. Biol. Anim. Biochem. Biophys., Suppl. 1, 31-46 6) NAKAHARA, T., YAMAUCHI, M. & KATAOKA, A. (1961): Studies on the antihormone against human chorionic gonadotrophin (Anti-HCG) in cattle I Experimental formation of the antihormone against human chorionic gonadotrophin in cattle Jpn. J. Anim. Reprod., 7, 27-32 (in Japanese with English summary) 7) NAKAHARA, T., YAMAUCHI, M., KATAOKA, A. & KANEDA, Y. (1964): Studies on the antihormone against gonadotrophin in cattle Proc. 5th Int. Congr. Anim. Rep rod. A. 1., Tl-ento, 2, 338-342 8) NEWCOMB, R., CHRISTIE, W. R, ROvVSON, L. E. A., W AL TERS, D. E. & BOUSFIELD, \V. E. D. (1979): Influence of close, repeated treatment and batch of hormone on ovarian response in heifers treated with PMSG J. Rep rod. Fertil., 56, 113-118 9) ROWSON, L. E. A. (1951): Methods of inducing multiple ovulation in cattle J. Endocrinol., 7, 260-270 10) SAUMANDE, J. & CHUPIN, D. (1977): Superovulation: A limit to egg transfer in cattle Theriogenology, 7, 141-149 11) SCANLON, P., SREENAN, ]. M. & GORDON, 1. (1968): Hormonal induction of superovulation in cattle J. A_gric. Sci., 70, 179-182 12) SCHAMS, D., MENZER, c., SCHALLENBERGER, E., HOFFMAN, B., HAHN, ]. &

Corpora lutea after PAIse; In rattle 113 HAHN, R. (1978): Some studies on pregnant mare serum gonadotrophin (PMSG) and on endocrine responses after application for superovulation in cattle In: Control of reproduction in the cow Ed. SREENAN, J. M., 122-143, The Hague: Commission of the European Communities 13) WILLETT, E. L., BUCKNER, P. ]. & MCSHAN, W. H. (1953): Refractoriness of cows repeatedly superovulated with gonadotrophins J. Dairy Sci., 36, 1083-1088