Predictive ability of selected subsets of single nucleotide polymorphisms (SNPs) in a moderately sized dairy cattle population.

Several studies have shown that computation of genomic estimated breeding values (GEBV) with accuracies significantly greater than parent average (PA) estimated breeding values (EBVs) requires genotyping of at least several thousand progeny-tested bulls. For all published analyses, GEBV computed from the selected samples of markers have lower or equal accuracy than GEBV derived on the basis of all valid single nucleotide polymorphisms (SNPs). In the current study, we report on four new methods for selection of markers. Milk, fat, protein, somatic cell score, fertility, persistency, herd life and the Israeli selection index were analyzed. The 972 Israeli Holstein bulls genotyped with EBV for milk production traits computed from daughter records in 2012 were assigned into a training set of 844 bulls with progeny test EBV in 2008, and a validation set of 128 young bulls. Numbers of bulls in the two sets varied slightly among the nonproduction traits. In EFF12, SNPs were first selected for each trait based on the effects of each marker on the bulls' 2012 EBV corrected for effective relationships, as determined by the SNP matrix. EFF08 was the same as EFF12, except that the SNPs were selected on the basis of the 2008 EBV. In DIFmax, the SNPs with the greatest differences in allelic frequency between the bulls in the training and validation sets were selected, whereas in DIFmin the SNPs with the smallest differences were selected. For all methods, the numbers of SNPs retained varied over the range of 300 to 6000. For each trait, except fertility, an optimum number of markers between 800 and 5000 was obtained for EFF12, based on the correlation between the GEBV and current EBV of the validation bulls. For all traits, the difference between the correlation of GEBV and current EBV and the correlation of the PA and current EBV was >0.25. EFF08 was inferior to EFF12, and was generally no better than PA EBV. DIFmax always outperformed DIFmin and generally outperformed EFF08 and PA. Furthermore, GEBV based on DIFmax were generally less biased than PA. It is likely that other methods of SNP selection could improve upon these results.

Fecal testosterone is elevated in high ranking female ibexes (Capra nubiana) and associated with increased aggression and a preponderance of male offspring.

We monitored fecal testosterone and progesterone levels in 26 adult ibexes (17 males, 9 females) in a captive herd Nubian ibex held on 250 ha tract to test if testosterone is associated with dominance. The ibexes were observed over a 20-month period, and including two mating seasons, during which time we collected fecal samples twice during early gestation and postpartum intervals and once during lactation and pre-rut season intervals. The social hierarchy was linear with age in adult males and nearly linear in adult females. High ranking males were in solitude, but females were aggregated with the kids in the presence of a dominant female. The testosterone concentration in the males in the pre-rut (211+/-12 ng/g; N=13; dominant male 296 ng/g) was significant higher than other seasons (P<0.05). High testosterone in dominant male at pre-rut was associated with a decrease in confrontations. The individuals with the highest average testosterone concentrations were the dominant male and female (166+/-82 ng/g; 130+/-32 ng/g, N=6, respectively). In females, testosterone was highest in during the post-partum interval and was associated with an increase in aggression. The three highest fertile ranking females had higher testosterone (119+/-14 ng/g vs. 92+/-18 ng/g, P<0.05) than the four subordinate females. The sex ratio of the offspring was 8M/3F for the three older females and 5M/7F for the younger females. In early gestation period, females with only male fetuses had higher testosterone than other gravidities (119+/-14 ng/g, N=6 vs. 91+/-18 ng/g, N=7, P<0.01). Progesterone was significantly higher in the eight multiparous pregnancies than in those with the five singletons (210+/-19 ng/g vs. 186+/-12 ng/g, P<0.02). We conclude that high testosterone in females is associated with an increase in aggressive confrontations in early- and mid-lactation. In contrast, increased testosterone during pre-rut in males is associated with fewer confrontations. In addition, the data support the hypothesis that higher ranking, older dimorphic female ungulates have higher testosterone concentrations and have more male births than subordinate females.

Thoracic outlet syndrome: a multidisciplinary problem with a perspective for microsurgical management without rib resection.

BACKGROUND: Thoracic outlet syndrome (TOS) refers to a group of complex symptoms in the upper extremity caused by compression of the brachial plexus, subclavian artery and vein. Different surgical approaches were described for the management of TOS. There is, however, no "gold standard" procedure for this complicated and multidisciplinary problem. OBJECTIVES: This study evaluated the effectiveness of a microsurgical neurovascular decompression in the treatment of TOS. METHODS: 11 patients suffering from TOS (for 1.3 to 15 years after the beginning of the symptoms) were selected for a treatment of the complex symptoms of pain (diffuse or irradiated to the arm and hand), aching or paresthesia in the neck, shoulder, anterior chest, upper extremity and hand. Four of the 11 patients were suffering from signs of vascular compression. Eight patients showed slow progressive neurological deterioration (distribution of the ulnar nerve) with partial muscle atrophy. Patients underwent a microsurgical treatment using a supraclavicular approach followed by brachial plexus neurolysis, scalenectomy and release of the subclavian artery and vein without rib resection. Postoperative results were classified, using Am. J. Surg. (176: 215-218, 1998) scale (4), as good, fair and poor. RESULTS: Surgical results were studied, with a follow-up of 24 to 48 months. Prior to surgery, all patients had partial or severe limitation in physical activities. Post-operative follow-up showed that 9 (82%) of the 11 patients returned to normal everyday physical activities with a complete or significant relief of the symptoms (good results). In 2 patients (18%) the pain decreased and the use of medication was reduced (fair results). Eight of the 11 patients returned to full or partial employment. There were no cases of poor results in the study. CONCLUSION: Microsurgical neurovascular decompression of TOS without a removal of the cervical or first rib using a supraclavicular approach is an effective treatment method for a relief or complete release from symptoms and allows most patients to return to an active normal life.

In vitro binding interactions of oral bacteria with immobilized fructosyltransferase.

AIMS: The objective of the present study was to explore the role of immobilized fructosyltransferase (FTF) in adhesion process. METHODS AND RESULTS: We investigated real-time biospecific interactions between several types of oral bacteria and recombinant FTF immobilized on a biosensor chip, using surface plasmon resonance technology. Streptococcus mutans, Streptococcus sobrinus and Actinomyces viscosus demonstrated significant binding to FTF. Actinomyces viscosus had a greater binding to FTF, with 373 Resonance Units (RU), than the other tested bacteria. The binding level to FTF of Strep. sobrinus was 320 RU, whereas Strep. mutans and Streptococcus salivarious show binding of 296 and 245 RU, respectively. The binding sensograms displayed different profiles for the tested bacteria at various cell density, suggesting a different affinity to immobilized FTF. CONCLUSIONS: The results from this study suggest that FTF may influence bacterial adherence and colonization of the dental biofilm. SIGNIFICANCE AND IMPACT OF THE STUDY: The biomolecular interaction analysis enables real-time monitoring of the interaction between adhesions of intact bacteria and their ligands, which might be crucial in the initial phase of biofilm development in vivo.

The UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase gene is mutated in recessive hereditary inclusion body myopathy.

Hereditary inclusion body myopathy (HIBM; OMIM 600737) is a unique group of neuromuscular disorders characterized by adult onset, slowly progressive distal and proximal weakness and a typical muscle pathology including rimmed vacuoles and filamentous inclusions. The autosomal recessive form described in Jews of Persian descent is the HIBM prototype. This myopathy affects mainly leg muscles, but with an unusual distribution that spares the quadriceps. This particular pattern of weakness distribution, termed quadriceps-sparing myopathy (QSM), was later found in Jews originating from other Middle Eastern countries as well as in non-Jews. We previously localized the gene causing HIBM in Middle Eastern Jews on chromosome 9p12-13 (ref. 5) within a genomic interval of about 700 kb (ref. 6). Haplotype analysis around the HIBM gene region of 104 affected people from 47 Middle Eastern families indicates one unique ancestral founder chromosome in this community. By contrast, single non-Jewish families from India, Georgia (USA) and the Bahamas, with QSM and linkage to the same 9p12-13 region, show three distinct haplotypes. After excluding other potential candidate genes, we eventually identified mutations in the UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase (GNE) gene in the HIBM families: all patients from Middle Eastern descent shared a single homozygous missense mutation, whereas distinct compound heterozygotes were identified in affected individuals of families of other ethnic origins. Our findings indicate that GNE is the gene responsible for recessive HIBM.

Physical and transcriptional map of the hereditary inclusion body myopathy locus on chromosome 9p12-p13.

Hereditary inclusion body myopathy (HIBM) is a group of neuromuscular disorders characterised by adult-onset, slowly progressive distal and proximal muscle weakness and typical muscle pathology. Previously, we have mapped the gene responsible for a recessive form of HIBM to chromosome 9p1 and narrowed the interval to one single YAC clone of 1 Mb in size. As a further step towards the identification of the HIBM gene, we have constructed a detailed physical and transcriptional map of this region. A high resolution BAC contig that includes the HIBM critical region, flanked by marker 327GT4 and D9S1859, was constructed. This contig allowed the precise localisation of 25 genes and ESTs to the proximal region of chromosome 9. The expression pattern of those mapped genes and ESTs was established by Northern blot analysis. In the process of refining the HIBM interval, 13 new polymorphic markers were identified, of which 11 are CA-repeats, and two are single nucleotide polymorphisms. Certainly, this map provides an important integration of physical and transcriptional information corresponding to chromosome 9p12-p13, which is expected to facilitate the cloning and identification not only of the HIBM gene, but also other disease genes which map to this region.

Functional importance of bovine myometrial and vascular LH receptors and cervical FSH receptors.

Bovine myometrium and cervix contain luteinizing hormone/human chorionic gonadotropin (LH/hCG) binding sites, LH receptor (LH-R) messenger RNA (mRNA), and LH-R protein. Expression of LH-R is dependent on the stage of the cycle. LH-R expression is high during the luteal phase but weak during the follicular phase. In both myometrium and cervix, LH activates both the adenylate cyclase and phospholipase C pathways, and the effect of LH on both pathways at each stage of the cycle is correlated with the amount of LH-R present in the tissue. Because activation of cyclic AMP (cAMP) is associated with myometrial quiescence, we suggest that LH activation of uterine cAMP could serve to keep the uterus quiescent during the luteal phase. On the other hand, in the uterine vein LH-R mRNA and LH-R are maximal during preestrus/estrus as opposed to the luteal phase. In the uterine vein, LH increases the expression of cyclooxygenase and production of both prostaglandin E2 (PGE2) and PGF2 alpha. Because PGF2 alpha is the physiological luteolytic signal in the cow, we suggest that this increase in prostaglandin production by the uterine vein is part of the physiological events leading to luteolysis. In addition to uterine LH-R, the bovine cervix at preestrus/estrus has high levels of follicle-stimulating hormone receptor (FSH-R) and its corresponding mRNA. As with LH-R, activation of FSH-R by FSH is associated with activation of a G protein-coupled receptor family that mediates the cAMP and inositol phosphate signaling pathways. Activation of these signaling pathways is associated with an increase in the expression of cyclooxygenase and production of PGE2. Because expression of the FSH receptor was maximal at the time of the FSH peak in the blood, we suggest a physiological role for FSH in the cervix relaxation and opening at estrus.

Actions of gonadotrophins on the uterus.

Binding sites for LH/hCG are found in the uterus of several species, including humans. In cattle and pigs, the LH receptor, its mRNA and LH receptor protein are present in the uterus throughout the oestrous cycle, and maximum expression occurs at the luteal phase. GnRH receptor is also expressed maximally in the human endometrium at the luteal phase. LH activates both the adenylate cyclase and phospholipase C pathways and increases the concentrations of cyclooxygenase and its products. Activation of LH receptors in the endometrium is associated with PGF production. In contrast, bovine uterine vein LH receptor mRNA and LH receptor concentrations are greatest during pro-oestrus-oestrus and LH increases the production of both PGE and PGF. FSH receptor and its mRNA are present in the bovine cervix and the concentrations are greatest at the time of the FSH peak value in the blood, indicating a physiological role for FSH in the relaxation and opening of the cervix. The presence of gonadotrophin and releasing factor receptors with a dynamic pattern in the endometrium, myometrium, oviduct and cervix of different species provides evidence that gonadotrophins and GnRH play a substantial role as molecular autocrine-paracrine regulators of the oestrous cycle and implantation.

Expression of functional luteinizing hormone (LH) receptor and its messenger ribonucleic acid in bovine endometrium: LH augmentation of cAMP and inositol phosphate in vitro and human chorionic gonadotropin (hCG) augmentation of peripheral prostaglandin in vivo.

Bovine endometrium contains LH/hCG binding sites and LH increases endometrial production of prostaglandin H synthase-2 (PGHS-2) and prostaglandin synthesis. This study showed that uterine endometrium contained both LH receptor mRNA transcript and a 93-kDa immunoreactive protein that bound to anti-rat LH receptor antibody. LH receptor and its mRNA were expressed maximally in the endometrium of cows from the luteal phase compared to the follicular phase of the estrous cycle. Furthermore, there was a response shown when incubation of endometrial minces from both pre-estrus/estrus and luteal phase (but not post-ovulatory phase) with LH or oxytocin (20 ng/ml) that resulted in a significant (p<0.02) increase in cAMP and total inositol phosphates. When Day 15 cows were injected i.v. with 3000 units hCG, the increase in peripheral 13,14-dihydro-15-keto PGF(2alpha) was 2.5-fold higher than saline controls or oxytocin. We conclude that LH stimulates endometrial cAMP and total inositol phosphates which results in increased formation of uterine PGHS-2 similar to LH effect on ovarian PGHS-2. The increased 13,14-dihydro-15-keto PGF(2alpha) production induced in vivo by injections of hCG indicates that LH may have a reinforcing role in luteolysis.

Gene integration into bovine sperm genome and its expression in transgenic offspring.

Transgenic bovine sperm were produced by restriction enzyme mediated insertion (REMI). REMI utilizes lipofection of linearized pEGFP and the corresponding restriction enzyme for integration into the sperm genomic DNA. The transgenic sperm were used in IVF to produce morula expressing GFP. When transgenic sperm were used for AI in two cows, the resultant calves expressed the exogenous DNA in their lymphocytes as determined by (a) PCR and RT-PCR; (b) specific emission of green fluorescence by GFP; and (c) Southern blot analysis. Data demonstrate that REMI is an efficient method for the production of transgenic sperm and corresponding offspring by AI or embryos by IVF.

LH/hCG receptors in the porcine uterus--a new evidence of their presence in the cervix.

High-affinity LH/hCG binding sites have been characterized in bovine, lepine, murine, human uteri and porcine myometrium and endometrium. In the present studies we analyzed these receptors in the porcine cervix. Radioreceptor ligand assays were performed with cell membrane preparations of the cervix which were analyzed for binding sites specificity, capacity and affinity. Corpus luteum and myometrium were used as positive control tissues. In the cervix there was little competition for receptor occupancy between hCG and porcine FSH (1.2%) or bovineTSH, porcine GH and porcine PRL (0.1%, 0.1% and < 0.001%; respectively) but porcine LH could completely inhibit the binding of [125I] hCG. There was not binding for LH/hCG in crude membrane preparations of kidney or skeletal muscle. The concentration (fmol/mg protein) of cervical LH/hCG receptor did not vary significantly during particular phases of the estrous cycle, except the early luteal phase (Days 6-7) when the level of LH receptors was very low (p < 0.05). The affinity of uterine LH/hCG binding sites in the cervix and the myometrium was not different from the affinity of LH/hCG binding sites in luteal cells. The porcine cervix as well as the myometrium contains a 75- and 48-kDa immunoreactive LH/cCG receptor proteins similar to corpus luteum. Southern blot of RT-PCR products performed to enhance the specificity and sensitivity of LH receptor transcripts determination in uterine tissues revealed that expected fragments of 740 and 470 bp were present in myometrium and corpus luteum. The cervix showed only 740 bp fragment. In situ hydridization showed the expression of mRNA for LH receptor in the epithelium of the cervix. Immunoreactive staining for LH/hCG receptors was also observed only in epithelial cells of the cervical tissue. Our studies are probably the first evidence demonstrating the specific LH/hCG binding sites in female cervix.

Follicle-stimulating hormone receptor and its messenger ribonucleic acid are present in the bovine cervix and can regulate cervical prostanoid synthesis.

The hypothesis that FSH regulates the bovine cervical prostaglandin E(2) (PGE(2)) synthesis that is known to be associated with cervical relaxation and opening at the time of estrus was investigated. Cervical tissue from pre-estrous/estrous, luteal, and postovulatory cows were examined for 1) the presence of bovine (b) FSH receptor (R) and its corresponding mRNA and 2) the effect of FSH on the PGE(2) regulatory pathway in vitro. The presence of bFSHR mRNA in the cervix (maximal during pre-estrus/estrus) was demonstrated by the expression of a reverse transcription (RT) polymerase chain reaction (PCR) product (384 base pairs) specific for bFSHR mRNA and sequencing. Northern blotting revealed three transcripts (2.5, 3.3, and 3.8 kilobases [kb]) in cervix from pre-estrous/estrous cows. The level of FSHR (75 kDa) was significantly higher (p < 0.01) in Western blots of pre-estrous/estrous cervix than in other cervical tissues. There was a good correlation between the 75-kDa protein expression and its corresponding transcript of 2.55 kb throughout the estrous cycle as described by Northern blot analysis as well as RT-PCR. Incubation of FSH (10 ng/ml) with pre-estrous/estrous cervix resulted in a 3-fold increase in the expression of FSHR and a 2-fold increase in both G protein (alpha(s)) and cyclooxygenase II. FSH (5-20 ng/ml) significantly increased (p < 0.01) cAMP, inositol phosphate (p < 0.01), and PGE(2) (p < 0.01) production by pre-estrous/estrous cervix but not by cervix at the other stages. We conclude that bovine cervix at the time of the peripheral plasma FSH peak (pre-estrus/estrus) contains high levels of FSHR and responds to FSH by increasing the PGE(2) production responsible for cervical relaxation at estrus.

Luteinising hormone receptor kinetic and LH-induced prostaglandin production throughout the oestrous cycle in porcine endometrium.

The present studies were performed to determine the LH/hCG receptor concentration and to evaluate the LH effect on prostaglandin production in porcine endometrium throughout the oestrous cycle. LH/hCG receptors in cell membrane preparations of the endometrium were found from days 12-14 and 15-16 of the oestrous cycle but not in preparations from days 6-7 and 18-20 using the ligand radioreceptor assay. Western blot analysis revealed, however, that the endometrium from all stages of the oestrous cycle contains a 75-kDa immunoreactive LH receptor protein similar to corpora lutea. The incubation of endometrial explants with LH (0, 1, 10 and 100 ng x mL(-1)) resulted in an increase of 13,14-dihydro-15-keto-PGF2alpha accumulation in a dose-dependent manner on days 5, 10, 14 and 16 of the oestrous cycle. The most effective dose was 10 ng LH x mL(-1) on days 5-16, but the strongest effect was found on days 14 and 16 (7.40 +/- 0.14 versus 12.75 +/- 1.40 and 5.67 +/- 0.35 versus 9.4 +/- 1.25 ng x 100 mg(-1) tissue/6 h, respectively; P < 0.01). It was also observed that 10 and 100 ng x mL(-1) of LH significantly increased cyclo-oxygenase expression to 135.2 and 123.5% respectively, above the control value (P < 0.01) on day 16 of the oestrous cycle. Our data suggest that LH receptors are of physiological significance in the porcine endometrium, since LH induces cyclooxygenase synthesis and increases prostaglandin production.

Expression of functional luteinising hormone receptor and its messenger ribonucleic acid in bovine cervix: luteinising hormone augmentation of intracellular cyclic AMP, phosphate inositol and cyclooxygenase.

The effect of luteinising hormone (LH) on bovine cervical tissues from three phases of the estrous cycle was studied. It was found that in the luteal phase cervix contained an LH receptor mRNA transcript and the 93 kDa LH receptor protein. Incubation of cervical minces from luteal phase with LH significantly increased (P < 0.05) the intracellular concentrations of LH receptor protein, cAMP, inositol phosphate (IP) and cyclooxygenase as well as the production of prostaglandin (PG) E2 (but not PGF2alpha). In contrast in the pre-oestrus/oestrus or post-ovulatory cervix, the signal for the transcript for LH receptor and the LH receptor protein was significantly lower than luteal cervix (P < 0.05) and the tissue did not respond to LH. We conclude that bovine cervix at luteal phase has high levels of LH receptor mRNA and receptor protein associated with the protein coupled receptor family that mediates cAMP and IP signalling responses. The receptors are coupled to PG synthase and generate cervical PGE2.

Castration prevents calcium channel blocker-induced gingival hyperplasia in beagle dogs.

1. The purpose of this study was to investigate testosterone's role on the calcium channel antagonist oxodipine-inducing gingival hyperplasia in a dog model. 2. Two experiments were conducted using castrated and intact male dogs. Oxodipine was administered orally for 90 days, at a dose of 24 mg/kg/day. In the first experiment, the occurrence of gingival hyperplasia was evaluated. In the second, the gingival index (GI) and gingival hyperplasia index (GHI) were recorded and correlated with serum levels of testosterone. 3. A significant positive correlation between GI, GHI and plasma testosterone was noted. Castrated dogs were injected with testosterone, 4 months after the start of oxodipine treatment, while in the non-castrated dogs, administration of oxodipine was stopped. Castration correlated with lack of GH, while testosterone injection to the same dogs was associated with an increase of GI and GHI. 4. Since it is known that testosterone receptors are present in the gingiva, it is proposed that oxodipine-induced gingival hyperplasia could be mediated by the calcium channel blocker on plasma testosterone levels.

Relationship between peripheral estrogen concentrations at insemination and subsequent fetal loss in cattle.

In a survey on pregnancy rate and embryonic losses in dairy cattle on 6 Israeli farms, cows (n = 78) were divided into 3 groups on the basis of ultrasonography at 21 d post insemination; pregnancy diagnosis at 40 to 50 d post insemination and blood progesterone (P4) levels at 21 d. The groups were either pregnant (P4 level > 1.0 ng/ mL); not pregnant (P4 < 0.5 ng/mL), or showed early embryo loss (P4 > 1.0 ng/mL and the presence of an embryonic vesicle on D 21 but later returned to estrus or were found not pregnant on D 40 to 50). On the day of insemination, peripheral estrogen was significantly higher (P < 0.05) in the early embryo loss group (15.3 +/- 1.1 pg/mL, n = 27) than in pregnant (9.4 +/- 0.6 pg/mL, n = 26) or not pregnant (9.6 +/- 0.7 pg/mL, n = 25) group. The cows on 3 farms which were fed 1 to 2 kg/d of vetch (Vicia sativa), an estrogenic legume, had higher estrogen concentrations on the day of insemination than cows (2 farms) fed other legumes (13.7 +/- 0.64, n = 58 vs 10.7 +/- 0.8 pg/mL, n = 42; P < 0.01). On one of the 3 farms, vetch was replaced with alfalfa after the first year. Following the cessation of vetch feeding the estrogen concentrations in the blood decreased from 32 +/- 5 pg/mL to 14 +/- 2 pg/mL (n = 9). These data suggest that high peripheral estrogen on the day of insemination is associated with early embryonic loss. These data also indicate that estrogen concentrations on the day of insemination can be influenced by diet.

Expression of functional luteinizing hormone (LH) receptor and its messenger ribonucleic acid in bovine uterine veins: LH induction of cyclooxygenase and augmentation of prostaglandin production in bovine uterine veins.

We have previously reported that bovine endometrium contains LH/human CG binding receptors and LH induces cyclooxygenase and prostaglandin production in the bovine endometrium. The present study investigated 1) whether bovine uterine vein and artery contain LH receptor messenger RNA (mRNA) and receptor protein and 2) whether LH can regulate the formation of vasoactive eicosanoids by the uterine vein. The uterine vein endothelium, but not the uterine artery, contained LH receptor mRNA transcript essentially identical to that found in the bovine corpus luteum. The uterine vein endothelium also contained a 95-kDa immunoreactive receptor protein that bound to rat anti-LH receptor antibody in Western blots. The LH receptor mRNA and LH receptor were maximally expressed in the uterine vein from cows in proestrus/estrus compared with cows in luteal or postovulatory phases. Incubation of endothelial minces of uterine vein with LH resulted in a 2-fold increase in cyclooxygenase concentration as determined by Western blot using an antibody to ram seminal vesicle cyclooxygenase. The increase in cyclooxygenase was maximal in cows in proestrus/estrus compared with postovulatory and luteal phase cows. Incubation of proestrous/estrous uterine vein or artery minces with LH or mellitin (a phospholipase A2 stimulator) caused increased production of eicosanoids. In the uterine vein, LH caused a significant increase in both PGF2alpha (basal 4.1 +/- 0.4 vs. 5.7 +/- 0.4 ng/100 mg x 6 h, P < 0.01; N = 9 cows) and PGE2 (basal 5.7 +/- 0.3 vs. 7.7 +/- 0.8 ng/100 mg x 6 h, P < 0.01; N = 6 cows) but had no effect on prostaglandin production by the artery. Mellitin increased PGF2alpha production by both uterine vein and artery minces but had no effect on PGE2 production in either tissue. Addition of steroids (progesterone, estradiol) or cytokines (tumor necrosis factor-alpha, IL-6) to the uterine vascular tissues had essentially no effect on prostanoid production. In summary, bovine uterine vein from proestrous/estrous cows expressed the LH receptor and its mRNA. Expression of the receptor may have physiological significance as LH induces cyclooxygenase and increases prostaglandin release in the uterine vein. The maximal stimulation of the receptor and its mRNA at proestrus/ estrus may serve to increase the amounts of prostanoids reaching the regressing corpus luteum either directly by increasing prostanoid production or indirectly by increasing the blood flow to the ovary.

Infertility in a cryptorchid bull: a case report.

A unilateral cryptorchid bull stationed in an AI center for 3.5 yr was studied to determine if maintaining such a bull could be justified. The following parameters were determined: quantity and quality of the ejaculates, basal and stimulated plasma testosterone concentrations, and the histology and testosterone concentrations of the testicles. The bull produced 232 ejaculates of which 125 (53.8%) were immediately discarded; the rest (107 ejaculations) were processed into pellets. Two of the 107 frozen ejaculates (2%) were found to be of excellent quality, 37 were (34.5%) of good quality, 45 were (42%) of satisfactory quality and 23 were (21.5%) of poor quality. Treatment of the calf with GnRH and hCG at 4 and 5 mo of age did not initiate the descent of the retained testicle. Testosterone concentrations measured at 14 mo, after hCG stimulus, indicated that the bull had impaired steroidogenesis when compared with 2 control bull calves. Post mortem examination revealed a small left testicle in the inguinal canal and a normal right testicle as well as normal secondary sex glands. During the breeding period at the AI center, the bull's peripheral testosterone concentrations decreased from 2.2 to 0.95 ng/ml Testosterone concentrations in the parenchymal tissue of the scrotal testicle were higher than in the parenchyma of the retained testicle (98.2 vs 53.9 ng/g). In contrast, the epididymis of the scrotal testicle had a lower testosterone concentration than the epididymis of the retained testicle (10.8 vs 33. 0 ng/g). On histological examination no spermatozoa were found in the retained testicle, the Sertoli cells showed fat degeneration, and fibrotic tissue surrounded the tubuli seminiferi. No pathological changes were found in the normal scrotal testicle. In conclusion, no justification was found for maintaining such a bull in the AI center for breeding purposes.

Regulation of bovine cervical secretion of prostaglandins and synthesis of cyclooxygenase by oxytocin.

Prostaglandin E2 (PGE2) can cause softening of the bovine cervix at oestrus when receptors for oxytocin (OT) are maximally present, indicating a relationship between OT and PGE2 production. It was therefore determined whether OT can stimulate prostaglandin synthesis or induce cyclooxygenase expression in cervical external os segments obtained from pre-oestrous-oestrous cows. Tissues were minced and incubated (50-100 mg mL[-1] 6 h[-1]) in the presence of OT (10 ng mL[-1]), progesterone (P4) (5 ng mL[-1]) and/or indomethacin (5 microg mL[-1]). It was found that OT stimulated basal PGE2 (7.79+/-1.22 ng 100 mg[-1], mean+/-s.e.m.; n = 6) in external os segments from pre-oestrous-oestrous cows (P < 0.03), whereas P4 and indomethacin inhibited basal and OT-stimulated PGE2 production (P < 0.05). Basal prostaglandin F2alpha (PGF2alpha) production was minimal (<1 ng 100 mg[-1]) and OT had no effect on its production. Expression of cyclooxygenase was measured by Western blot analysis following incubation of the tissue (100 mg 1.5 mL[-1] 3 h[-1]) in the presence of OT (10 ng mL[-1]) and in the presence of P4 (5 ng mL[-1]). It was found that OT stimulated the induction of cyclooxygenase II (79+/-10%; n = 7, P < 0.05). In contrast, P4 inhibited the basal expression of this enzyme (-40+/-5%, n = 7, P < 0.05) in the presence or absence of OT. It is concluded that, in vitro, OT stimulates PGE2 synthesis by the bovine cervix at oestrus and that this effect is mediated by cyclooxygenase.