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The ovarian structures identified at the time of ET are important for the selection of recipients. In previous report, the first-wave dominant follicle, located ipsilateral to the corpus luteum on the ovary, was associated with reduced conception rate after artificial insemination. Thus, a similar locational relationship may affect conception rate during embryo transfer. Data from 297 transfers of fresh embryos to virgin heifers were analyzed aiming to check the effect of first-wave dominant follicle location in relation to the corpus luteum on conception rate using a multivariable logistic regression model with six confounders. The location of the first-wave dominant follicle in relation to the corpus luteum location had no significant effect on conception rate, suggesting that it is not necessary to consider the firstwave dominant follicle size and location in the ovaries for recipient selection.

Overproduction of free radicals is controlled by antioxidant defense mechanisms. These defense mechanisms are achieved by antioxidant enzymes such as catalase (CAT). The current study aimed to assess the changes in steroid hormones, oxidant/antioxidants biomarkers, lipid profiles/liver functions indices, renal function biomarkers and minerals metabolism in non-pregnant, lactating or pregnant one-humped she-camels (Camelus dromedarius) pre-synchronized with controlled internal drug releasing. The study also focused on the correlational relationships between steroid hormones and the oxidant/antioxidant biomarkers, lipid profiles and liver functions indices, renal functions and mineral metabolism in these she-camels. The study was conducted on apparently healthy dromedary she-camels (n = 60) during breeding season. A sexually active camel-bull was introduced to she-camels pre-synchronized with CIDR. Fifty to sixty days after natural mating, she-camels were examined for pregnancy. She-camels were divided into three main groups according to both pregnancy and lactation as following: pregnant (PREG, n = 38) which was kept as control one, non-pregnant and lactating (LACT, n = 8), and non-pregnant and non-lactating she-camels (NPREG, n= 14). Steroid hormones, i.e., progesterone (P4), estradiol (E2) and cortisol, oxidant indictors, i.e., malondialdehyde (MDA), antioxidant biomarkers, i.e., superoxide dismutase (SOD), total antioxidant capacity (TAC), CAT and reduced glutathione (GSH), lipid profiles indices, renal functions and related minerals were assessed. The present study confirmed the efficacy of using CIDR for synchronization in she-camels. Significant elevations in serum steroids hormones in PREG compare with LACT and NPREG. The highest concentrations of MDA as lipid peroxidation and oxidative stress indictors and lowest levels of antioxidant biomarkers except for SOD, i.e., TAC, CAT and GSH, were reported in PREG compared with LACT and NPREG. PREG showed the highest liver enzymes activities and lowest total protein values. Remarkable increases in serum concentrations of renal function parameters and phosphorous (P) were observed in PREG when compared with the other two groups. The investigated she-camels revealed significant correlation between steroid hormones and the oxidant biomarkers, antioxidant biomarkers, liver functions, renal functions and minerals metabolism parameters. P4 showed positive correlations with antioxidant biomarkers, i.e., TAC, CAT and GSH, and serum aspartate aminotransferase (AST) activities, whereas negative correlations were reported between P4 and renal functions biomarkers, i.e., blood urea nitrogen (BUN), creatinine (Cr) and creatinine kinase (CK), and minerals metabolism parameters, i.e., P and magnesium (Mg), in CIDR pre-synchronized she-camels. In contrast, E2 and cortisol showed negative correlations with antioxidant biomarkers, i.e., TAC, CAT and GSH, lipid profiles/liver functions indices, i.e., AST, alkaline phosphatase (ALP) and γ-glutamyl transferase (GGT), CK and Mg, however, positive correlations were demonstrated between E2 and cortisol, and MDA, Cr and P in investigated she-camels. In conclusion, the present study confirmed the efficacy of using CIDR for synchronization in she-camels. The highest MDA levels as indictors for oxidative stress and the lowest antioxidant levels, i.e., TAC, CAT and GSH, except for SOD in pregnant she-camels, were attributable to physiological oxidative stress as excellent compensatory responses observed in the PREG group to face such a physiologic stage. Moreover, lower P levels in non-pregnant she-camels would be contributed to failure of conception or early embryonic death. The investigated she-camels revealed significant correlations between steroid hormones and the oxidant indicators, antioxidant biomarkers, lipid profile indices and renal functions biomarkers that provided better understanding for physiological stress during pregnancy in camels.

Peripartum disorders in dairy cows negatively influence their productivity and reproductive performance. However, only a few reports have clearly indicated the influence of such disorders on the productivity and reproductive performance at a local-area or cow-level in Japan. This study aimed to elucidate the influence of diseases occurring within 60 days after calving on subsequent productivity and reproductive performance. Accordingly, a wide-area database on dairy production was used for epidemiological analysis; subsequently, multivariable analysis was performed to investigate the association of such diseases with productivity or reproductive performance in 6,545 cows from 178 farms in Fukuoka. We used 305-day energy-corrected milk (305 ECM) as an index of productivity and conception and culling as indices of reproductive performance. With regard to causality, mixed-effects model was used for analyzing the association between disease and productivity, and Cox proportional hazard model was used for analyzing the association between disease and reproductive performance. Compared to the disease absence group, the disease presence group demonstrated significantly lower 305 ECM [−154 kg; 95% confidence interval (CI), −229 to −79] and risk of pregnancy [hazard ratio (HR), 0.85; 95% CI, 0.80–0.91] and higher risk of culling (HR, 1.36; 95% CI, 1.17–1.59). These results indicate that, in Fukuoka, dairy cows affected by diseases within 60 days after calving exhibit lower productivity and reproductive performance. Therefore, proper dairy cow management during the peripartum period to prevent diseases during early lactation may maintain or improve productivity.

The purpose of this study is to compare the assessment of pre- and postpartum oxidative stress-related causal indicators and other metabolites in cows with postpartum subclinical ketosis (SCK). The prepartum serum malondialdehyde concentration and body condition score (BCS) were elevated in the SCK cows (n=17) compared to healthy controls (n=12), while the insulin sensitivity check index was lower in the SCK cows than in the controls. Oxidative stress is enhanced in cows with prepartum higher BCS, causing decreased insulin sensitivity, and may be associated with onset of postpartum SCK. However, paraoxonase alone might be insufficient to assess the antioxidant state because of no difference in pre- and postpartum activities between the two groups.

The study aimed to describe the changes in clinical findings and serum levels of gastrin, pepsinogen and chloride (Cl) in dairy cattle with displacement of the abomasum (DA) from day 0 until day 30 after surgery and to evaluate their diagnostic and prognostic value in evaluation of the abomasal func-tion. The study was conducted on DA cattle (n=25) belonging to dairy farms in Hokkaido area, Japan. Cows were examined and sampled at days 0 (surgery), 7 and 30. Based on blood β-hydroxybutyric acid (BHBA) at day 0, DA cows were classified into three categories; DA only (

Highlights • Epidemiological study of embryo transfers of japanese black (JB) embryos. • JB's bloodline combination was also found to be a risk factor for embryo fertility. • Success of JB embryo transfer may depend on differences in genetic background., The aims of this study were 1) to summarize the current status of Japanese Black (JB) embryo transfer into Holstein heifers, which is carried out on a commercial basis in Japan, and 2) to reveal fertility risk factors, including those from the environment (year and season of transfer), recipient (age, number of transfers, clinical status of the ovaries) and embryo (quality, stage, state, genetic background). We used data from 4467 JB fresh or frozen embryo transfers into Holstein heifers conducted by Zen-noh Embryo Transfer Center during 2016–2018, and the differences in fertility risk due to factors related to the environment, recipient, and embryo were statistically evaluated. Differences in fertility risk due to each variable were observed, leading to significant differences in fertility with respect to year of transfer, embryo quality, embryo state, and embryo breed. These results suggest that the fertility of JB embryos might depend on differences in genetic background. There have been no previous reports of differences in embryo fertility due to the differences among JB's bloodline combinations. In the future, overall reproductive efficiency must be monitored, including the effects of different bloodline combinations on the success of embryo recovery and transfer.

Serum concentrations of non-esterified fatty acids (NEFA) and very low-density lipoprotein (VLDL) in close-up dairy cattle were compared in relation to parity. Data were obtained from 37 nulli/primiparous (NP) and 24 multiparous (MU, parity: 2-7) cows between 14 days and 1 day prepartum. A positive correlation (r=0.684, P

Blood levels of progesterone (P4), estradiol-17β (E2), calcium (Ca), triglyceride (TG), and total protein (TP) were monitored in a captive female loggerhead turtle throughout a nesting season that included three 13- or 14-d internesting intervals. We observed the turtle's ovaries to monitor the appearance of shelled eggs, using ultrasonography, and compared the results of blood analyses and ovary observations. The blood P4 level remained low (

The study aimed to describe the pattern of changes in clinical findings and lipid metabolism profiles in dairy cattle with displacement of the abomasum (DA) from day 0 until day 30 after operation. The study was conducted on DA cattle (n= 25) belonged to dairy farms in Hokkaido area, Japan. Cows were examined and sampled at days 0 (operation), 7 and 30. They were clinically and biochemically examined to estimate BCS and many serum biochemical constituents such as lecithin:cholesterol acyltransferase (LCAT) and apolipoprotein B-100 (apoB-100), β-hydroxybutyric acid (BHBA), non-esterified fatty acids (NEFAs) and aspartate amino transferase (AST). Based on blood BHBA at day 0, DA cows were classified into three categories; DA only (

The incidence of peripartum disorders in dairy herds negatively influences productivity and reproductive performance. Concrete data from local areas are helpful for explaining the importance of peripartum management to dairy farmers. This study was conducted to clarify the association of culling and death rate within 30 days after calving with productivity or reproductive performance in 179 dairy herds in Fukuoka, Southern Japan. A database was compiled from the records of the Livestock Improvement Association of Japan, the Dairy Cooperative Association and the Federation of Agricultural Mutual Relief Association. In this study, we created a comprehensive database of dairy farm production data for epidemiological analysis and used a general linear mixed model to analyze the association of culling and death rate within 30 days after calving with milk production or reproductive performance. The database can be used to describe, analyze and predict the risk of production. A cross-sectional analysis with contrasts was applied to investigate the association of cows served by AI/all cows, pregnant cows/cows served by AI, days open, milk yield and somatic cell counts with culling and death rate within 30 days after calving. The days open value significantly increased with increasing rate of culling and death within 30 days after calving (P for trend

This study reports a viable means of identifying the vitellogenic cycle and limited estrus period in hawksbill turtles for the purposes of developing captive breeding program, based on the combination of blood metabolite parameters (triglyceride, total protein, and calcium levels), feeding status, and ovary condition. Follicle size of two focal captive females showed clear seasonal changes, with major development occurring between March and May (19.0-24.4 mm), and exceeding 25 mm between June and September. Triglyceride, total protein, and calcium levels dropped with follicular development and maintenance (March to October), and then began to rise when follicular retraction occurred from October onwards. The two focal turtles reduced food intake during intensive follicular development (April to May). These findings suggest that blood metabolite parameters and feeding conditions are inferred by the vitellogenic cycle. An additional 10 females exhibiting follicular development were mated with a single male for 7-day period between May and June. Follicle size was measured immediately prior to pairing, and a statistically significant difference in follicle size of 10 females was recorded between the seven failed (20.9 mm) and three successful (23.6 mm) mating events. This indicates follicle development is essential to successful mate and monitoring of vitellogenic cycle may help improve the success rates of captive hawksbill breeding programs.

The aim of this study was to characterize peripartum metabolic profiles, including the insulin sensitivity index, in cows diagnosed with subclinical ketosis (SCK) in the early stage of lactation. Cows that calved from January 2011 through December 2014 on a dairy farm with alarm level prevalence of SCK in Hokkaido, Japan (L’objectif de la présente étude était de caractériser les profils métaboliques péri-partum, incluant l’index de sensibilité à l’insuline, chez des vaches avec un diagnostic d’acétonémie subclinique (ASC) tôt en début de lactation. Les vaches qui ont mis bas entre janvier 2011 et décembre 2014 sur une ferme laitière avec une prévalence d’ASC à un degré d’alarme à Hokkaido, Japon (n = 175) ont été utilisées. Du sang et les pointages de condition corporelle (PCC) ont été obtenus au moment d’examens de santé réguliers lors de deux périodes consécutives, la première entre 14 et 2 j avant la parturition, et la seconde entre 3 et 14 j après la parturition. Les animaux ont été divisés en trois groupes lors de l’échantillonnage post-partum : un groupe ASC avec 35 vaches pluripares et 15 vaches primipares ayant des concentrations de β-hydroxybutyrate (BHBA) ≥ 1,2 mM sans signe clinique, un groupe malade avec 36 vaches pluripares et 9 vaches primipares qui ont reçu un traitement entre le moment de la parturition et la prise d’échantillon post-partum, et un groupe témoin composé de 49 vaches multipares et 31 vaches primipares avec des concentrations de BHA1,2 mM. L’indice quantitatif de sensibilité à l’insuline révisé pré-partum était significativement plus bas dans les groupes de vaches multipares ASC et vaches malades que dans le groupe témoin, démontrant ainsi une diminution de la sensibilité à l’insuline chez ces vaches mais pas chez les vaches primipares. L’ASC pré-partum était significativement plus élevé seulement dans les groupes ASC multipares et malade. La concentration pré-partum d’apolipoprotéine B-100 (ApoB-100) était significativement diminuée chez les vaches multipares du groupe malade, suggérant une lipidose hépatique. Inversement, les vaches primipares avaient une concentration plus élevée d’ApoB-100. La sensibilité à l’insuline diminuée en pré-partum chez les vaches ASC multipares et vaches malades était considérée pour faciliter la progression d’ASC à la suite de la mise-bas.(Traduit par Docteur Serge Messier).

This study presented information about the semen evaluation of captive male hawksbill sea turtles, Eretmochelys imbricata, based on an extended 15-mo study using the electro-ejaculation technique. In particular, we demonstrated that hawksbill sperm, which is underactive just after ejaculation, was activated by the presence of urine. The findings are useful for developing optimal semen collection techniques for future artificial insemination programs of hawksbill turtles.

To develop ovulation induction techniques, we investigated the effects of follicle- stimulating hormone (FSH) administration on ovulation in captive hawksbill turtles Eretmochelys imbricata. Porcine FSH preparation was administered by intramuscular injection to four hawksbill turtles with fully-developed follicles (21.6–23.8 mm, measured using ultrasonography) in July or August 2009. Blood samples were obtained and subjected to plasma progesterone measurement, and ovaries and oviducts were observed by ultrasonography just before, and 1–6 days after, FSH administration. One day after the administraion, the plasma progesterone concentration significantly increased from the basal level (

Blood estrone sulfate (E(1) S), estrone (E(1) ), estradiol (E(2) ) and progesterone (P(4) ) in newborn piglets were measured to clarify the relationships among birth and placental weight, vitality of offspring and litter size. First, the association between vital status (normal, weak and stillborn) from 165 newborn piglets of 18 litters and steroid concentrations; second, steroid concentrations from 152 newborn normal piglets and litter size; and third, steroid content in fetal placenta from 50 newborn normal piglets of six litters and litter size, were investigated. In the normal group, the birth and placental weight were significantly higher than those in the other groups. Blood E(1) S levels in the stillborn group were significantly lower, whereas E(1) , E(2) and P(4) were significantly higher compared to the normal group. Blood and placental E(1) S levels in the small litter group were significantly higher than those in the other groups. However, there was no significant difference among the three litter size groups in the levels of steroid hormones in maternal blood. These results indicate that vitality of newborn piglets is related to E(1) S concentration of neonate, to birth weight and placental weight. However, steroid hormone concentrations of newborn piglets were greatly affected by the number of littermates.

The genetic structure of Aphis gossypii Glover (Hemiptera: Aphididae) populations was characterized using microsatellite analysis of insects sampled from pear and citrus orchards at three locations in the summer seasons of 2001 and 2003. These data will enable more precise forecasting of infestation and will be of value to the development of better control methods. In total, 89 genotypes were found in 500 aphid samples. The diversity indices in aphid populations on pear trees fluctuated but showed a decrease with time in citrus orchards. Japanese aphid populations have greater variation in their microsatellite loci than African, European, or Southeast Asian populations. Approximately half of the genotypes were found in only one colony, whereas the remainder were identified in two or more colonies. Fifteen genotypes appeared in different years, in samples from different areas, or on different host plants. Our data suggest the existence of aphid populations with pear-adapted genotypes and with a permanent parthenogenetic life cycle. Some of the genotypes included genes conferring resistance to pirimicarb and pyrethroid insecticides. Japanese A. gossypii populations may maintain their large genetic variation through differences in their life cycles.

In field screening tests of synthetic pheromone candidates for Japanese sesiid species, a mixture of (3Z,13Z)-octadecadien-1-ol and (3Z,13Z)-octadecadienyl acetate successfully attracted male moths of Glossosphecia romanovi, a harmful pest of vine trees. The GC-EAD and GC-MS analyses of the pheromone gland extract revealed that the female moths produced the alcohol and acetate in a ratio of about 20:1, in addition to three other minor structure-related components.

To clarify the physiological changes of sperm morphology in active Thoroughbred stallions during the breeding season, we examined the dismount semen collected from the penile urethra immediately after service. The spermatozoa were analyzed for relationships between the morphology and the stallion's age or the number of services. Seasonal variation was apparent in the rate of the sperm tail abnormalities, spermatozoa with cytoplasmic droplets, appearance of medusa cells, and sperm head length. Area and width of the sperm head correlated negatively with age (P

In 2003, gall midge larvae of the genus Resseliella (Diptera: Cecidomyiidae) were found infesting the cores of Japanese pear, Pyrus pyrifolia (Rosaceae), in Fukushima Prefecture, Japan. Symptoms of infestation are similar to those noted previously for Japanese pear in Japan and Korea. From 2007 to 2008, gall midge larvae that were similar to those found in Fukushima Prefecture were detected in Tottori and Shimane Prefectures, Japan under the bark of Japanese pear. Based on morphological comparison with known congeners associated particularly with Rosaceae in the Palaearctic region and those occurring in Japan, we concluded that the gall midge infesting Japanese pear is a new species of Resseliella. DNA sequencing data also supported this conclusion. This new species seems to be identical to the ‘pear codlin midge’ reported previously from Japan and Korea. We describe the gall midge as Resseliella yagoi sp. nov. and provide information on host plant cultivars, distribution, behavioral and life history traits, and pest status.

Field surveys and light trap catches of Nezara viridula and N. antennata (Hemiptera: Pentatomidae) in Shikoku and Chugoku Districts, Japan showed that N. viridula is now distributed along the northern coastline of Shikoku District, and in Yamaguchi Prefecture, and along the northern coastline of Shimane Prefecture, south of Izumo, Chugoku District. The present data together with previous reports suggest that the northward range expansion of N. viridula is possibly due to global warming because the monthly mean temperature for January in newly invaded areas has exceeded 5°C in recent years, for example, since 1986 in Fukuoka, below which the winter mortality of N. viridula adults becomes higher. Around the northern limit of N. viridula in Shimane Prefecture, it was not found in April‐August 2008 because the monthly mean temperature for January 2008 fell below 5°C, below which the winter mortality of N. viridula becomes higher. Thus, the northern limit retreated depending on winter temperature. We confirmed the absence of N. viridula from 1979 until August 2008 in Izumo, Shimane Prefecture, and in 2007‐2008 in Tottori Prefecture. Most areas along the southern seacoast in Shikoku District were occupied only by N. viridula, suggesting that it has replaced N. antennata by interspecific mating. In the Chugoku District, no area was occupied only by N. viridula, but it was more abundant than N. antennata in southern Yamaguchi Prefecture, indicating that N. viridula is now replacing N. antennata in that area.

In a previous study, we found two amino acid substitutions, Ser431Phe and Ala302Ser, in the Drosophila Ace paralogous acetylcholinesterase (AP-AChE) genes from pirimicarb-resistant Aphis gossypii. Ser431Phe is responsible for the development of pirimicarb resistance and Ala302Ser may play a role in insensitivity to organophosphorus insecticides. In this study, we developed the two types of molecular diagnostics for detecting these mutations. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)-based method was developed to detect the Ser431Phe and Ala302Ser mutations. A PCR amplification of specific alleles (PASA) method, designated to detect Ser431Phe mutations allowed the three genotypes to be discriminated more rapidly and simply than by PCR-RFLP. Genotyping of samples collected from Japanese pear and Satsuma mandarin orchards in Japan was carried out using PCR-RFLP. We revealed that the genetic composition of the A. gossypii orchard population changes with time without exposure to insecticide and that molecular diagnostics are useful for monitoring the development of insecticide resistance. Although both mutations were frequently detected in field populations, pirimicarb-resistant aphids did not seem to always constitute a large proportion in field populations in Japan. We found several individuals which had Ser302 without Phe431. This finding denies the concept that this genotype is inviable from the viewpoint of enzymatic kinetics.

Reproductive efficiency and performance in dairy cattle has been declining over the last 20 years in Japan. Recently, this has resulted in serious problems in dairy herds. There have been changes in the animals themselves and in the animal's environment, e.g. the genetic potential for milk yield has improved, the herd size of dairy farms has been expanding, the housing system of dairy cattle has been changing from tie stall to free stall, and total mixed ratio (TMR) feeding systems have become widespread. It is not clear whether the animals have adapted adequately to these environmental changes. Up till now, reproductive management has been undertaken by monitoring animal performance and/or hormonal treatments, and this has resulted in acceptable reproductive performance. However, conception and pregnancy rates have continued to decline, and the calving to calving interval has continued to extend. Consequently, the average parity and the average age at culling in dairy cattle have been declining. The most common causes of culling in dairy cattle are reproductive disorders in Japan. Therefore, in future, prevention of reproductive disorders will be required for both reproductive efficiency and animal welfare. During late pregnancy and the transition from the pregnant, non-lactating state to the non-pregnant, lactating state, dramatic changes are occurring in the dam including an increase in the fetal-placental mass and calving. Thus, the demand for energy, protein and minerals by the conceptus increases, the space within the abdominal cavity and the rumen capacity decreases due to the increased volume of the conceptus, the local immunological relationship between the fetal and maternal placenta dramatically changes, and physiological homeostasis is activated to adapt to these changes. If cattle can't maintain homeostasis before calving, the incidence of reproductive diseases will be greatly increased. We have been examining reproductive, nutritional and immunological factors to predict the occurrence of reproductive disorders as early as possible and to develop strategies to prevent them. It is unlikely that all dairy farms in Japan will be able to improve reproductive performance with general advice, due to the wide variation in feeding systems and management in Japan. Therefore, specific advice needs to be tailored to each herd, based on management systems employed within each herd. We have proposed that it is important to identify common risk factors across herds, to use these factors as an index for disease control and reproductive management and finally to demonstrate the relationship between these factors and fundamental improvement of the reproductive efficiency. We propose this approach with the aim of providing a breakthrough in improving reproductive performance in dairy cattle in Japan. The focus of this review will be that such an approach is important for improvement of the reproductive efficiency in Japanese dairy cows.

The objective of this study was to evaluate the efficiency of gonadotropin releasing hormone (GnRH) and GnRH doses in synchronizing follicular wave emergence as a pretreatment for superovulation in cattle. Fourteen Holstein-Friesian cows 6 days from estrus were randomly assigned to receive 100 microg (n=4), 50 microg (n=5), or 25 microg (n=5) of GnRH. Superovulation was induced with injections of porcine FSH (pFSH) twice daily, decreasing the dose (total 42 AU) over 5 days beginning 2.5 days after receiving GnRH. On the 7th and 8th injections of pFSH, 750 microg of PGF(2alpha) was also given. With the exception of one cow that was given 50 microg of GnRH, ovulation was induced in all cows from the three groups and the new follicular wave emergence was observed. The total number of follicles for the 25 microg GnRH group was less than that observed for the 100 microg GnRH group (P0.05), although there were no differences between the 100 microg, 50 microg and 25 microg GnRH groups with respect to the number of preovulatory follicles (or=10 mm) and CL. The numbers of normal embryos were greater for the 25 microg GnRH group than the 100 or 50 microg GnRH groups (P0.01); however, the numbers of ova/embryos did not differ significantly between the three groups. These results suggest that 25 microg of GnRH was sufficient to induce ovulation and follicular wave emergence. On day 6 of the estrous cycle, a reduction of the dose of GnRH to synchronize follicular wave emergence as a pretreatment for superstimulation promotes transferable embryos.

Reproductive diseases after parturition are a serious problem in dairy cattle. It is important to predict postpartum reproductive diseases early and to develop prophylaxis. The objectives of this study were to demonstrate changes in the peripheral blood concentration of interleukin-6 (IL-6) before parturition, which was mainly produced by T helper 2 type (Th2) cells, and to investigate a correlation between the IL-6 concentration and the occurrence of the postpartum retained placenta, endometritis and/or follicular cyst in dairy cattle. Twenty-seven Holstein-Friesian cows were used for this study. Thirteen had no clinical disease, 8 had retained placenta, 4 were diagnosed with endometritis by vaginal inspection, and 2 were diagnosed with follicular cyst by rectal palpation at 1 and 2 months after parturition. Blood samples were collected 60 days pre- and post-partum. They used for IL-6, progesterone (P(4)) and estradiol-17beta (E(2)) concentration determination. This study showed that the IL-6 concentration prepartum was higher than postpartum. Low levels of IL-6 and P(4) in peripheral blood prepartum tended to affect retained placenta and a high level of IL-6 prepartum tended to affect endometritis. These results indicate that measurement of change in the IL-6 concentration during pregnancy is one useful tool for predicting crisis in postpartum reproductive diseases in dairy cattle.

We investigated the therapeutic effects of a progesterone releasing intravaginal device (PRID) on cystic ovarian disease (COD) and reproduction performance of cows. The possible influence of PRID on metabolic and/or health status was also examined. A total of 40 Holstein-Friesian cattle, with ovarian cystic structures,or =2.5 cm in diameter, persisting for more than 7-14 days, without a corpus luteum (CL) were used for the study. PRID or placebos were inserted into the vagina for 12 days. Five animals lost the intravaginal device before removal and one was culled. Based on plasma progesterone concentration on the day of treatment, 20 (17 PRID and 3 placebos) of the remaining 34 cows had follicular cysts (progesteroneor =1 ng/ml) and 14 (10 PRID and 4 placebos) had luteal cysts (progesterone1 ng/m l). Fourteen (82%) of the PRID-treated follicular cystic cows responded with formation of a CL within 14 days after treatment, and an overall conception rate of 53.8%. Likewise, 70% of the treated luteal cystic cows responded with CL formation and 71.4% conception rate. No significant differences were observed in hematocrit (Ht), white blood cell count and serum levels of glucose, blood urea nitrogen, aspartate aminotransferase, and alanine aminotransferase, between the day of PRID insertion and removal, in animals with follicular and luteal cysts. PRID treatment resulted in ovulation 2-4 days later and formation of a CL in cows that recovered.

A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use.

Various adverse effects of endocrine disruptors on the reproductive organs of male animals have been reported. We found that UDP-glucuronosyltransferase (UGT) activities towards bisphenol A, testosterone and oestradiol were significantly decreased in liver microsomes prepared from adult male Wistar rats administered with the endocrine disruptor bisphenol A (1mg/2 days for 2 or 4 weeks). However, suppression of the transferase activities was not observed in female rats, even after bisphenol A treatment for 4 weeks. Diethylstilbestrol, which is well known as an endocrine disruptor, had the same effects, but p-cumylphenol had no effect on UGT activities towards sex hormones. Co-administration of an anti-oestrogen, tamoxifen, inhibited the suppression of the transferase activities by bisphenol A. Western blotting analysis showed that the amount of UGT2B1, an isoform of UGT which glucuronidates bisphenol A, was decreased in the rat liver microsomes by the treatment. Northern blotting analysis also indicated that UGT2B1 mRNA in the liver was decreased by bisphenol A treatment. The suppression of UGT activities, UGT2B1 protein and UGT2B1 mRNA expression did not occur in female rats. The results indicate that bisphenol A treatment reduces the mRNA expression of UGT2B1 and other UGT isoforms that mediate the glucuronidation of sex hormones in adult male rats, and this suggests that the endocrine balance may be disrupted by suppression of glucuronidation.

The objectives of this study were to show changes of blood parameters for nutrition during pregnancy and to examine the relationships between the blood parameters and calf birth weights, calf viability, time required for expulsion of fetal membrane, and the fetal membrane weights. Forty-one Holstein Friesian pregnant cows were used. The duration of the dry period was 74 ± 2 (SEM) days. The average milk yield (4% FCM) per cow per lactation for 305 days was 9,795 ± 146 kg. Mean gestation length, body weight of cows at parturition, and cotyledonary weight were 283.7 ± 0.5 days, 761 ± 11 kg, and 1562 ± 33g, respectively. Mean birth weights were 47.4 ± 1.1 kg for female, and 49.8 ± 0.8 kg for male calves. Of the 41 cows, 10 had weak calves and 13 had retained fetal membranes (RFM). No significant effects of parity, bull, lactation length, milk yield, gestation length, cows' body weights, and gender of calves on the cotyledonary and calf birth weights, incidences of neonatal weakness and RFM were shown. Cows showing low plasma glucose and TP concentrations in mid and late lactation periods had lower calf birth weights and cotyledonary weights, and a higher incidence of neonatal weakness. Likewise, cows with low glucose, cholesterol and Ca concentrations in plasma during the late dry period had a higher incidence of RFM. The results indicate that low intake of energy and protein during late lactation and early dry periods adversely affects feto-placental development, leading to neonatal weakness and RFM. Low intake of energy and Ca during the dry period may also cause RFM.

This study was carried out to investigate changes in pituitary response to GnRH on gonadotrophin secretion in prepubertal heifers. A total of 50 prepubertal Holstein-Friesian heifers were treated with 1 μg/kg GnRH intravenously at 1, 2, 4, 6 and 8 months of age, and plasma samples were collected from the jugular vein at 0 to 360 min after GnRH treatment. Plasma concentrations of LH and FSH were measured by RIA. Increase in concentrations of LH and FSH, induced by GnRH, were observed in all heifers from 1 month of age, and the concentrations of LH and FSH at 30 min after GnRH treatment were significantly greater than those before GnRH treatment in heifers of all ages. The time from the GnRH administration to the appearance of the peak of LH and FSH rise was similar at each age and, was prolonged with age. The peak concentration and the amount of release from the pituitary of LH rise increased with age, while those of FSH had a tendency to decrease with age. These results indicate that the pituitary gland already has reactivity to GnRH in heifers by 1 month of age, that the capacity of LH release to GnRH in the pituitary gland develops with age, and that the regulatory mechanism for the secretion of LH and FSH develops differently in prepubertal heifers. This study suggests that the development of the capacity to secrete LH secretion in response to GnRH in the pituitary gland before puberty is one of the factors for deciding the time of the onset of puberty in heifers.

Induction of superovulation using human menopausal gonadotriphin (hMG) in Japanese Black cattle can result in the recovery of a higher percentage of high quality embryos compared with that using porcine follicle stimulating hormone (FSH). In order to clarify the endocrinological mechanism involved in this discrepancy, 30 superovulation sessions of 17 Japanese Black cattle were studied. Fifteen cattle were super-stimulated with hMG (total 600 IU), and the remaining 15 cattle were given FSH (total 20 mg). The plasma profiles of LH, estradiol-17beta (E2) and progesterone (P4) were correlated, and the embryo quality was investigated. The total number of ova recovered and the number of transferable embryos tended to be larger in the hMG-treated group than in the FSH-treated group. The percentage of excellent embryos tended to be higher in the hMG-treated group than in the FSH-treated group (54.3 and 28.7%, respectively, p < 0.10). The E2 level increased during the first 3 days after the initial administration of either hMG or FSH and was higher in the hMG-treated group than in the FSH-treated group (p < 0.05). During this period, the E2 level could be categorized into one of the following three types according to whether it increased or decreased and according to the degree of increase or decrease: (1) increase by a factor of 1.2 or more (quick increase type) (2) slight increase by a factor less than 1.2 (slow increase type), and (3) no increase (unstable increase type). In the group treated with hMG, 66.7% of the animals (10 of 15 cattle) showed a quick increase in the E2 level. However, in the FSH-treated group, 40% (six of 15) of the animals showed a slow increase in the E2 level. The plasma LH level increased dramatically 8 h prior to the peak level in both the hMG- and FSH-treated groups, and then it returned to the basal level 12 h later. After the administration of prostaglandin (PG)F2alpha, the LH peak level was attained within 44 h in 80% of the animals in the hMG-treated group, whereas in the FSH-treated group, the LH peak level tended to be reached later. The P4 level did not increase during the period of hMG or FSH treatment and decreased drastically following administration of PGF2alpha. After the onset of oestrus, the P4 level was higher in the hMG group than in the FSH group, and 5 to 7 days after oestrus, the level remained higher in the hMG group than in the FSH group (p < 0.05). After the first 3 days of hMG administration, the E2/P4 ratio was higher than that after FSH administration. Furthermore, on the day following PGF2alpha administration, the ratio was significantly higher in the hMG group than in the FSH group (p < 0.05). These results indicate that superovulation in cattle given hMG results in a significant increase in plasma E2 during the first 3 days and that the increase in the plasma P4 level is larger a few days after oestrus and thereafter compared with FSH-induced superovulation. Therefore, such plasma level profiles may be related to the increased recovery rate of high quality embryos.

This study was carried out to investigate changes in gonadotrophin secretion in response to estradiol, and to clarify the change of the positive feedback action of estradiol in prepubertal heifers. Four prepubertal Holstein-Friesian heifers were treated with 2 μg/kg estradiol benzoate intramuscularly at 1, 3, 5, 7 and 9 months of age, and plasma samples were collected every 3 h for 36 h after estradiol treatment. Plasma concentrations of LH, FSH and estradiol were measured by RIA. The changes in peripheral estradiol concentration after estradiol treatment were similar in pattern with peaks at 3 h in all ages. LH and FSH rise induced by estradiol were observed in heifers after 3 months of age, and the time from the estradiol administration to the appearance of the peak of gonadotrophin rise gradually shortened with the age. The peak concentration of LH rise increased, while the concentration of FSH rise did not change with age. These results indicate that the hypothalamus and pituitary gland already have reactivity to estradiol in heifers by 3 months of age, and that estradiol positive feedback action on LH secretion develops with age in prepubertal heifers. We concluded that the development of estradiol positive feedback action on LH secretion before puberty may be one of the essential factors for deciding the time of the onset of puberty in heifers.

This study was designed to clarify the characteristics of changes in plasma concentrations of reproductive hormones in heifers from birth to puberty. Weekly or daily hormonal changes were observed in 39 heifers. Daily changes in the concentration of follicle-stimulating hormone (FSH) demonstrated a consistent cycle of hormone changes over a 7- to 8-day period in heifers from approximately 10 days to 9 months old. Weekly changes in reproductive hormones showed that there were three brief periods in heifers between birth and puberty in which dramatic changes occur. The first period was the first week after birth, during which a reciprocal relationship between steroid hormones and gonadotropins was observed. At birth, the concentrations of steroid hormones were higher than those at any other age. These hormone levels rapidly decreased within the first week after birth. Gonadotropin levels, however, increased from birth to 1 week of age. The second period of major change was at approximately 4 weeks of age when there was an increase in the concentrations of luteinizing hormone (LH), estradiol-17β, testosterone, and immunoreactive inhibin. The third period was the last 5 weeks before the first ovulation, when there was an increase in the concentrations of estradiol-17β followed by an increase in (LH). These results suggest that regular hormone changes start from 10 days after birth and that the periods from birth to 4 weeks of age and the last 5 weeks before the first ovulation in heifers are important to the development of reproductive functions before puberty.