The Relationship Among Vitamin C, β‐carotene,Vitamin A,Progesterone and Oestradiol 17‐β Concentrations in Plasma and Cyst Fluid of Holstein Cows with Ovarian Cyst

The aims of this study were to determine the concentrations of the progesterone, oestradiol‐17‐β, vitamin A, C and β‐carotene in plasma and cyst fluid and to relate these values with cystic diameter and membrane thickness of Holstein cattle with ovarian luteal cyst. 1650 Holstein cows were examined for the presence of the ovarian cyst and luteal and follicular cystic ovaries were obtained following slaughtering in personal slaughterhouse in Konya‐Turkey. 15 Luteal and 15 follicular cystic ovaries were distinguished by rectal palpation and by post mortem ultrasonographic examination. Plasma and cyst fluid, hormone and vitamin analyses were carried out by EIA method and spectrophotometric measurement respectively. Although there was no relationship between β‐carotene and vitamin A in plasma and cyst fluid of both cyst type and hormone concentrations, the vitamin C concentration of cyst fluid was found significantly higher in luteal cyst than in follicular cyst. Moreover, there is a positive correlation among values of the vitamin C concentrations of cyst fluid and cystic membrane thickness, plasma and the cyst fluid progesterone concentrations, but there is a negative correlation among the vitamin C concentrations of cystic fluid and oestradiol 17β levels of plasma and cyst fluid. In conclusion, vitamin C concentration of cyst fluid supported ultrasonographic and endocrinologic findings. Also, it can be postulated that vitamin C is probably effective on progesterone synthesis in the luteal tissue of cyst.     

Involvement of Plasma Progesterone, Oestradiol-17β and Cortisol in Ovulatory Response to Gonadotropin-releasing Hormone in Dairy Cows with Cystic Follicles

The aim of the present study was to examine the plasma concentrations of progesterone, oestradiol-17beta and cortisol in the cows with cystic follicle and to examine its relationship with the ovulatory response to gonadotropin-releasing hormone (GnRH). Eighty-five post-partum Holstein-Friesian cows with cystic follicles regardless of the presence of corpus luteum were studied. Follicular size, presence of corpus luteum and occurrence of ovulation were checked by palpation per rectum. Blood collection and palpation per rectum were conducted on days 0, 7 and 14. Gonadotropin-releasing hormone was administered at day 7. Plasma concentrations of progesterone, oestradiol-17beta and cortisol were determined. Progesterone concentrations of <3.2, 3.2-4.8 and >4.8 nmol/l were defined as low, intermediate and high, respectively. Sixty-three (74.1%) of 85 cows showed low (<3.2 nmol/l =1 ng/ml) progesterone concentrations on day 0. Only 40 (47.1%) of them showed low-low pattern of progesterone at days 0 and 7. In 27 (31.8%) of them, progesterone concentration had increased by day 14. Of 22 cows having high progesterone concentration (>/=4.8 nmol/l) on day 0, corpus luteum was not detected in 18 cows (21.2%). Only in 10 cows, cystic follicle disappeared after GnRH administration. However, only one of 27 cows in which progesterone pattern was low-low-high at days 0, 7 and 14 experienced ovulation of the cystic follicle. Significantly lower oestradiol-17beta concentration was found on day 7 in cows showing a low-low-low pattern than a low-low-high pattern of progesterone (43.0 +/- 4.6 vs 55.8 +/- 2.8 pmol/l, p < 0.05). There was no significant difference in cortisol concentration on any days (days 0, 7 and 14) between cows showing a low-low-low and low-low-high pattern of progesterone. These results suggest that approximately one-fifth of cows diagnosed to have ovarian cysts possess luteal cysts and that a high oestradiol-17beta concentration at the time of GnRH administration is involved in the subsequent ovulation of the follicle, although ovulated follicle may not be cystic.     

Altered Expression of 3β‐HSD,CYP17 and 17β‐HSD in the Foetal Porcine Gonads in Response to Anti‐androgen Flutamide Exposure

We investigated whether the limited access to androgens during late prenatal period alters expression of steroidogenic enzymes involved in androgen production: 3β‐hydroxysteroid dehydrogenase/Δ5‐Δ4 isomerase (3β‐HSD), cytochrome P450 17α‐hydroxylase/17,20‐lyase (CYP17) and 17β‐hydroxysteroid dehydrogenase type 1 (17β‐HSD1) or type 3 (17β‐HSD3) in the foetal porcine gonads. Pregnant gilts were injected with anti‐androgen flutamide (for seven days, 50 mg/day/kg bw) or corn oil (control) starting at 83 (GD90) or 101 (GD108) gestational day. To assess 3β‐HSD, CYP17 and 17β‐HSD1 or 17β‐HSD3 expression, real‐time PCR and immunohistochemistry were performed. In testes from flutamide‐treated foetuses, increased 3β‐HSD and CYP17 mRNA expression was observed in the GD90 group, while decreased 3β‐HSD and 17β‐HSD3 mRNA expression and increased CYP17 mRNA expression were found in the GD108 group. CYP17 and 17β‐HSD3 were localized in Leydig cells. Following flutamide administration, the intensity of CYP17 immunostaining was higher in both treated groups, while 17β‐HSD3 intensity was lower in the GD108 group. In ovaries from flutamide‐treated foetuses in the GD90 group, mRNA level for 3β‐HSD was elevated, but it was diminished for CYP17 and 17β‐HSD1. In the GD108 group, flutamide treatment led to lower mRNA level for 3β‐HSD but higher for CYP17. 3β‐HSD was found in granulosa cells, while CYP17 was localized within egg nests and oocytes of forming follicles. Following flutamide treatment, the intensity of 3β‐HSD and CYP17 immunostaining was higher in the GD90 and GD108 groups, respectively. Immunohistochemical staining for 3β‐HSD was restricted to the ovary. Concluding, diminished androgen action in the porcine foetal gonads during late gestation induces changes in steroidogenic enzymes expression, which may led to changes in gonadal function. However, it seems that androgens exert diverse biological effects depending on the gestational period.     

13,14‐Dihydro‐15‐Keto Prostaglandin F2α Release in Response to Oxytocin Challenge Early Post‐Partum in Anoestrous Nelore Cows Submitted to Temporary Calf Removal and Progesterone Priming

The study evaluated, in early post‐partum anoestrous Nelore cows, if the increase in plasma oestradiol (E2) concentrations in the pre‐ovulatory period and/or progesterone priming (P4 priming) preceding ovulation, induced by hormonal treatment, reduces the endogenous release of prostaglandin PGF₂αand prevents premature lysis of the corpus luteum (CL). Nelore cows were subjected to temporary calf removal for 48 h and divided into two groups: GPE/eCG group (n = 10) and GPG/eCG group (n = 10). Animals of the GPE/eCG group were treated with a GnRH agonist. Seven days later, they received 400 IU of eCG, immediately after PGF₂α treatment, and on day 0, 1.0 mg of oestradiol benzoate (EB). Cows of the GPG/eCG group were similarly treated as those of the GPE/eCG group, except that EB was replaced with a second dose of GnRH. All animals were challenged with oxytocin (OT) 9, 12, 15 and 18 days after EB or GnRH administration and blood samples were collected before and 30 min after OT. Irrespective of the treatments, a decline in P4 concentration on day 18 was observed for cows without P4 priming. However, animals exposed to P4 priming, treated with EB maintained high P4 concentrations (8.8 ± 1.2 ng/ml), whereas there was a decline in P4 on day 18 (2.1 ± 1.0 ng/ml) for cows that received GnRH to induce ovulation (p < 0.01). Production of 13,14‐dihydro‐15‐keto prostaglandin F₂α (PGFM) in response to OT increased between days 9 and 18 (p < 0.01), and this increase tended to be more evident in animals not exposed to P4 priming (p < 0.06). In conclusion, the increase in E2 during the pre‐ovulatory period was not effective in inhibiting PGFM release, which was lower in P4‐primed than in non‐primed animals. Treatment with EB promoted the maintenance of elevated P4 concentrations 18 days after ovulation in P4‐primed animals, indicating a possible beneficial effect of hormone protocols containing EB in animals with P4 priming.     

Relationship of Peripheral Estrogens and Testosterone Concentrations to Sexual Behavior in Normal and Cystic Cows

Peripheral estrogens and testosterone values on each day of the estrous cycle in the plasma of normal cows (n=6) were compared to those in single serum samples from cystic animals. The highest plasma testosterone was detected on the day before estrus (day 20), and estrogen peaks were observed on days 16 and 20. Serum from cows (n=125) with cystic ovarian degeneration, previously classified as either anestrous or nymphomaniac, was assayed only for either estrogens or testosterone. Additional serum samples were collected from 39 cystic cows to measure both steroids. Almost all of the results from cystic animals were within or below the ranges recorded in the normal cows. No significant differences for either steroid was found between the anestrous or nymphomaniac groups (P>.05). Therefore, it was not possible to demonstrate any relationship between either hormone or behavioral pattern.     

Cystic Degeneration in Porcine Ovaries - Second Communication: Concentrations of Progesterone, Estradiol-17β, and Testosterone in Cystic Fluid and Plasma; Interpretation of the Results

Contents: The content of progesterone, estradiol-17β, and testosterone of plasma and cystic fluid was determined in 79 sows with ovarian cysts. The average progesterone concentration of sows with dark corpora lutea (CL) was higher than of sows with pale or absent CL (39.4 vs. 8.7 vs. 8.0 ng/ml plasma; p < 0.001; and 7512 vs. 3644 vs. 2723 ng/ml cystic fluid, respectively; p < 0.001). The cystic fluid of animals with oligocystic ovaries (10 cystslanimal) had a significant higher progesterone concentration in comparison to potycystic animals (7200 vs. 3682 ng/ml; p < 0.001). Testosterone and estradwl-17β levels in plasma and in cystic fluid of polycystic animals were significantly higher in comparison to oligocystic animals (Plasma-Testosterone: p < 0.01; Plasma-Estradwl: p < 0.05; Cyst-Testosterone: p < 0.01; Cyst-Estradiol: p < 0.001). In oligocystic ovaries testosterone in cysts exceeded the estradiol-17β levels, whereas in polycystic ovaries the situation was vice versa (p < 0.001).
It is suggested that cystic ovarian degeneration in the sow is not exclusively a gradually progressing process, rather then a complex syndrome with three components, were characterized by a separate course of development (oligocystic, polycystic. oligo-polycystic syndrome).     

Effect of β‐Carotene Supply During Close‐up Dry Period on the Onset of First Postpartum Luteal Activity in Dairy Cows

The aim of this study was to examine the effect of β‐carotene supply during the close‐up dry period on the onset of first postpartum luteal activity in dairy cows. Twelve cows were supplied with 2000 mg of β‐carotene (20 g Rovimix^®β‐Carotene containing 10%β‐carotene; DSM Nutrition Japan K.K., Tokyo, Japan) by oral administration daily from day 21 before expected calving date to parturition. Fourteen cows (control) did not receive β‐carotene supplementation. Blood samples were obtained on days 21, 14 and 7 before expected calving date and on days 1, 7, 14, 21 postpartum. When the plasma progesterone concentration exceeded 1 ng/ml by day 21 postpartum, luteal activity was assumed to have been initiated. The result showed that serum β‐carotene concentrations in the β‐carotene cows were higher than in the control cows during the experimental period (p < 0.01). The number of cows with the onset of luteal activity by day 21 postpartum was 9/12 in the β‐carotene cows and 4/14 in the control cows (p < 0.05). Retinol, certain metabolic parameters and metabolic hormones concentrations did not differ between β‐carotene and control cows. In addition, serum retinol concentration in β‐carotene cows without luteal activity was lower than in β‐carotene cows with luteal activity (p < 0.05), and serum gamma‐glutamyl transpeptidase concentration in β‐carotene cows with luteal activity (p < 0.05) and control cows without luteal activity (p < 0.01) was higher than in control cows with luteal activity. In conclusion, β‐carotene supply during the close‐up dry period may support the onset of luteal activity during early lactation in dairy cows.     

Progesterone Profiles in the Caudal Vena Cava and Jugular Vein in Response to Pulsatile Luteinizing Hormone Stimulation Induced by GnRH Treatment During the Mid-luteal Phase in Lactating Dairy Cows

The aim of this study was to examine whether increased frequency of luteinizing hormone (LH) pulses influences luteal progesterone (P₄) secretion by measuring progesterone concentrations at the secreted (caudal vena cava) and circulating levels (jugular vein) in lactating dairy cows. Cows received six intravenous administrations of 2.5 μg of GnRH (gonadorelin acetate, n=4) or 2 ml saline (n=3) at 1-h intervals on 12.4 ± 0.4 (mean ± SE) days after ovulation. Blood samples were collected from the caudal vena cava and jugular vein every 12 min for 12 h (6 h before and after treatment). During the 6 h after treatment, frequency of LH pulses (5.3 ± 0.3 and 3.0 ± 0.0 pulses/6 h) and mean LH concentration (0.50 ± 0.06 and 0.38 ± 0.05 ng/ml) were greater (P<0.05) in GnRH-treated cows than in saline-treated cows. Mean P₄ concentration and amplitude of P₄ pulses in the caudal vena cava during the 6 h after treatment were greater (P<0.05) in GnRH-treated cows than in saline-treated cows, but the frequency of P₄ pulses was not different between the groups. Mean P₄ concentration in the jugular vein during the 6 h after treatment was also higher (P<0.05) in GnRH-treated cows than in saline-treated cows (7.0 ± 1.3 and 5.4 ± 0.9 ng/ml). These results indicate that the increased frequency of LH pulses stimulates progesterone secretion from the functional corpus luteum and brings about higher P₄ concentrations in the circulating blood in lactating dairy cows.     

Effect of Oestrous Synchronization with Estradiol 17β and Progesterone on Follicular Wave Dynamics in Dairy Heifers

An experiment was designed to evaluate the effects of estradiol‐17β (E17β) on follicular wave dynamics and ovulatory response in Holstein heifers receiving either a progestogen ear‐implant (Crestar^®; Intervet International b.v. Boxmeer, The Netherlands) or an intravaginal progesterone‐releasing device [controlled internal drug release‐bovine device (Eazibreed, CIDR‐B^®; Bodinco BV, Alkmaar, The Netherlands)]. For comparison, another group of heifers was also synchronized using Crestar plus an injection of estradiol valerate (EV) and norgestomet as recommended by the pharmaceutical company. Twenty 20–22‐month‐old cycling Holstein heifers were allocated to one of the following treatment groups at random stages of the oestrous cycle: (I) simultaneous insertion of Crestar and intramuscular injection of 3 mg norgestomet and 5 mg EV (Crestar 9 + EV 9); (II) simultaneous insertion of Crestar and intramuscular injection of 5 mg E17β (Crestar 9 + E17β 9); (III) insertion of Crestar followed 2 days later by intramuscular injection of 5 mg E17β (Crestar 9 + E17β 7); or (IV) insertion of CIDR‐B device followed 2 days later by intramuscular injection of 5 mg E17β (CIDR 9 + E17β 7). The CIDR‐B or Crestar implants were removed after 9 days and all heifers received 500 μg Cloprostenol (Estrumate^®, Pitman‐Moore Nederland BV, Houten, The Netherlands). Ovarian ultrasonographic examinations were performed once daily during the synchronization period using a B‐mode scanner equipped with a 7.5 MHz linear‐array transrectal transducer. In addition, heifers were scanned every 12 h after implant/device withdrawal until 3 days after ovulation in order to monitor follicular activity, detect ovulation and subsequent early luteal formation. Detection of oestrus was performed every 6 h for 4 days after device/implant removal. Oestrus was observed 24–32 h before ovulation in all heifers. The mean hours interval from treatment withdrawal to ovulation was not significantly different (84.0 ± 16.5, 77.6 ± 4.1, 73.6 ± 4.1 and 64.0 ± 4.4 h for treatments I, II, III and IV, respectively; p > 0.1). However, the variance for heifers treated with EV + norgestomet was significantly larger (Levene’s Test; p < 0.01) than those treated with E17β. All E17β treatments resulted in dominant follicle suppression and a new wave emerged 4.1 days after treatment compared with 6.6 days for the EV + norgestomet treatment (p < 0.05). The time from emergence of the new ovulatory wave to ovulation was longer for the new wave that emerged after E17β treatment (9.2 ± 0.3 days) than after EV + norgestomet treatment (6.9 ± 0.4 days; p < 0.05). The results of this study suggest that the four treatments used were effective in inducing synchronous behavioural oestrus and ovulation. However, a higher degree of oestrus and ovulation synchrony was observed in heifers treated with E17β than in heifers treated with EV + norgestomet. Synchronization treatments with exogenous E17β or EV + norgestomet at the time of progestin device insertion (Crestar or CIDR‐B) or 2 days later in heifers can regulate a different emergence pattern of ovarian follicular development in randomly cyclic heifers. The E17β was effective in inducing follicular suppression and resulted in the consistent emergence of a new follicular wave.     

Plasma Concentrations of 13, 14‐Dihydro‐15‐keto‐Prostaglandin F2α, Progesterone and Cortisol During Periparturient Period in Yaks (Poephagus grunniens L.)

An attempt was made to determine plasma concentrations of, 13, 14‐dihydro‐15‐keto‐prostaglandin F_2α (PGFM), cortisol and progesterone during periparturient period in yak. Plasma PGFM level showed an increasing trend beginning day 5 prior to parturition (0.48 ± 0.14 ng/ml) and increased steeply thereafter to reach a peak level (17.16 ± 1.31 ng/ml) on the day of parturition. The levels, then, declined sharply on day 1 postpartum to reach 1.20 ± 0.40 ng/ml and thereafter declined gradually over the days to reach 0.28 ± 0.09 ng/ml on day 20 postpartum and this level was maintained with fluctuation within narrow limits thereafter till conclusion of the blood sampling on day 90 post‐calving. The plasma progesterone concentration on days 7 and 6 before parturition was high (2.10 ± 0.10 and 2.12 ± 0.10 ng/ml, respectively). The level then decreased gradually and abrupt fall was observed 1–2 days before parturition and became basal on day of parturition (0.24 ± 0.04 ng/ml). This basal level was maintained till the end of the blood sampling on day 90 postpartum. Plasma cortisol level showed an increasing trend beginning day 2 prior to parturition (2.36 ± 0.65 ng/ml) and increased steeply thereafter to reach a peak level (26.65 ± 5.28 ng/ml) on the day of parturition. The levels, then, declined gradually over the days and touched 2.36 ± 0.25 ng/ml on day 3 postpartum and this level was maintained with fluctuation within narrow limits thereafter till day 7 post‐calving.     

Clinical Response in Anestrous Dairy Cows with High or Low Blood Progesterone Levels to Treatment with the PGF Analog Alfaprostol*

Contents: In a controlled field trial, 211 anestrous dairy cows with palpable corpora lutea were treated once with a luteolytic dose of the PGF analog alfaprostol (1.5 mgl 100 kg bw) or with a placebo solution. In cows not responding with heat within 10 d, the same treatment was repeated. All cows showing heat were bred. Blood progesterone values were determined at the days of treatment, 2 or 3 d thereafter and at breeding. As reported previously, 109 of 199 cases available for final evaluation showed initially high progesterone values (>6.36 nmol/L) and responded to one or two treatments with heat (alfaprostol us placebo: 96.6% us 48.0%). Breeding resulted in an overall pregnancy rate of 71.4% us 3 7.2%. Of the ninety cows showing initially low blood levels of progesterone (<6.36 nmol/L), 93.5% responded to the first or second alfaprostol treatment with heat versus 27.3% of the placebo treated controls. Breeding of these cows resulted in an overall pregnancy rate of 69.6% (alfaprostol) us 27.3% (placebo). Cows with low progesterone levels treated with alfaprostol once or twice responded with a higher level of heat than anticipated from silently cycling animals. This indicates that the well described gonadotropin releasing effects of PGF in cattle may have resulted in the stimulation of follicular growth, followed by overt or covert estrus, ovulations, conceptions and the formation of corpora lutea. Inhalt: Klinische Ergebnisse der Behandlung mit einem Prostaglandin F Analog, Alfaprostol, bei Milchkühen mit hohem oder niedrigem Blutprogesteronspiegel In einem doppelten Blindversuch erhielten 211 anöstrische Milchkühe, die ein palpier-bares Corpus luteum aufwiesen, eine luteolytische Behandlung mit 1.5 mg/100 kg KGW des PGF Analogs Alfaprostol oder eine Plazeboinjektion. Bei Kühen, die innerhalb von 10 Tagen keine Brunst erkennen lieβen, wurde diese Behandlung wiederholt. Alle Kühe, die in Brunst kamen, wurden besamt. Blut für Progesteronbestimmungen wurde am Tag der Behandlung, am 2. oder 3. Tag danach und am Tag der Besamung entnommen. Serumprogesteron wurde rnit einem RIA bestimmt. Wie schon früher berichtet, wiesen 109 von 199 Fällen, die zur Endauswertung zur Verfügung standen, am Tage der Behandlung einen hohen Progesteronwert auf (<6.36 nmol/L) und reagierten auf die 1. oder 2. Behandlung mit Brunst (Alfaprostol : Plazebo=96.6% : 48%). Die Besamung resultierte in einer Trächtigkeitsrate von 71% für Alfaprostol und von 37.2% für Plaze-bobehandlung. Von den 90 anöstrischen Kühen rnit niedrigem Progesteronwert bei Behandlungsbeginn (<6.36 nmol/L) reagierten 93.5% mit Brunst auf die 1. oder die 2. Behandlung mit Alfaprostol, aber nur — wie zu erwarten — 27.3% der mit Plazebo behandelten Tiere; 69.6% (Alfaprostol) und 27.3% (Plazebo) wurden tragend. Kühe mit niedrigem Progesteronspiegel reagierten somit auf die PGF-Behandlung, entgegen den Erwartungen, ebenso mit einem hohen Prozentsatr an Brunst und nachfolgender Konzeption. Es ist bekannt, daβPGF bei Kühen Gonadotropine freirusetzen vermag. Dieser Effekt könnte für die Anregung von Follikelwachstum, Brunst oder Stillbrün-stigkeit, Ovulation, Konzeptionen und die Bildung von Gelbkörpern verantwortlich gemacht werden.     

Dietary supplementation of β‐hydroxy‐β‐methylbutyrate in animals – a review

The leucine metabolite β‐hydroxy‐β‐methylbutyrate (HMB) has been studied by many researchers over the last two decades. In particular, the utility of HMB supplementation in animals has been shown in numerous studies, which have demonstrated enhanced body weight gain and carcass yield in slaughter animals; positive immunostimulatory effect; decreased mortality; attenuation of sarcopenia in elderly animals; and potential use in pathological conditions such as glucocorticoid‐induced muscle loss. The aim of this study was to summarize the body of research on HMB supplementation in animals and to examine possible mechanisms of HMB action. Furthermore, while the safety of HMB supplementation in animals is well documented, studies demonstrating efficacy are less clear. The possible reasons for differences in these findings will also be examined.     

Effects of β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin in β‐carotene‐deficient Japanese Black cows

Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG₁, but colostral IgM, IgG₂, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG₁, IgA and IgM concentrations in cows, but plasma IgG₁ concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG₁ concentrations in β‐carotene‐deficient cows.     

Measurement of C‐reactive protein and Prostaglandin F2α Metabolite Concentrations in Differentiation of Canine Pyometra and Cystic Endometrial Hyperplasia/Mucometra

Canine pyometra is a dioestrus period disease in which systemic inflammatory response syndrome (SIRS) is a common outcome due to the response of the body to the bacterial infection. The purpose of this study was i) to differentiate canine pyometra and cystic endometrial hyperplasia (CEH)/mucometra by measuring serum C‐reactive protein (CRP) and prostaglandin F_2α metabolite (PGFM) concentrations in blood and ii) to compare serum concentrations of CRP and PGFM in bitches with a pathological uterus (pyometra or CEH/mucometra) to concentrations in bitches with a healthy uterus. Mean CRP concentrations were found significantly higher (p < 0.001) in dogs with pyometra compared to those with CEH/mucometra or healthy uterus. However, no statistical difference could be detected between the groups for mean PGFM concentrations. Mean white blood cell count (WBC), alkaline phosphatase (ALP) and total protein concentrations were found significantly higher (p < 0.001) in dogs with pyometra. Escherichia coli was the most frequently isolated microorganism from dogs with pyometra (64.3%). Edwardsiella spp. was detected in a single case of pyometra for the first time. In conclusion, our results demonstrate that serum CRP concentrations were increased in dogs with pyometra and thus we conclude that serum CRP concentration but not PGFM might be useful as a marker to differentiate a case of CEH/mucometra from pyometra in female dogs. To the authors' knowledge, this is the first report in which Edwardsiella spp. has been isolated in the canine uterus.     

Correlation of Whole Blood Concentrations of Acetoacetate, β-Hydroxybutyrate,Glucose and Milk Yield in Dairy Cows as Studied Under Field Conditions

The whole blood concentrations of acetoacetate (AA concn), β-hydroxybutyrate (BHB concn) and glucose (gluc concn) of 662 Ayrshire and Friesian dairy cows were measured and their milk yield during the indoor-housing period was recorded. Simple correlations among these parameters were evaluated. The correlation between the AA concn and the BHB concn (r = 0.869) was statistically highly significant (P < 0.001), as were the correlations of the logarithmic value of the AA concn with the gluc concn (r = —0.471) and with the milk yield (r = 0.259), and the correlation between the BHB concn and the glue concn (r = —0.288). The milk yield was found also to be associated with the BHB concn and the glue concn (P< 0.001). The associations between each pair of blood parameters were highly significant, too (P < 0.001). The AA concn was taken to be at least as good an indicator of the energy status of dairy cows as the BHB concn and the gluc concn. The AA concn is not diet-derived like the BHB concn and not as stress-sensitive as the blood concentration of free fatty acids and its diurnal variation is not as wide as the BHB concn and the gluc concn in subclinically ketotic cows. Thus the AA concn may be used as a proxy of the energy status and the ketotic stage of dairy cows under field conditions.Key words: acetoacetate, ß-hydroxy butyrate, glucose, energy status, dairy cattle     

β‐hydroxy‐β‐methyl butyrate promotes leucine metabolism and improves muscle fibre composition in growing pigs

The aim of this study was to investigate the effects of excess leucine (Leu) vs. its metabolites α‐ketoisocaproate (KIC) and β‐hydroxy‐β‐methyl butyrate (HMB) on Leu metabolism, muscle fibre composition and muscle growth in growing pigs. Thirty‐two pigs with a similar initial weight (9.55 ± 0.19 kg) were fed 1 of 4 diets for 45 days: basal diet, basal diet + 1.25% L‐Leu, basal diet + 1.25% KIC‐Ca, basal diet + 0.62% HMB‐Ca. Results indicated that relative to the basal diet and HMB groups, Leu and KIC groups exhibited increased Leu concentrations and decreased concentrations of isoleucine, valine and EAAs in selected muscle (p < 0.05) and had lower mRNA levels of MyHC I and higher expression of MyHC IIx/IIb (p < 0.05), and there was no significant difference between the basal and HMB‐supplemented groups. Moreover, the mRNA expression levels of AMPKα and UCP3 were higher but the myostatin mRNA levels were lower in the soleus muscle of the HMB group than those from other groups (p < 0.05). These findings demonstrated that doubling dietary Leu content exerted growth‐depressing effects in growing pigs; dietary KIC supplementation induced muscular branched‐chain amino acid imbalance and promoted muscle toward a more glycolytic phenotype; while dietary HMB supplementation promoted the generation of more oxidative muscle types and increased muscle growth specially in oxidative skeletal muscle, and these effects of HMB might be associated with the AMPKα‐Sirt1‐PGC‐1α axis and mitochondrial biogenesis.     

Expression of VEGFR and PDGFR‐α/‐β in 187 canine nasal carcinomas

Radiotherapy represents the standard of care for intranasal carcinomas. Responses to tyrosine kinase inhibitors (TKIs) have been reported but data on expression of target receptor tyrosine kinases (rTKs) is limited. This study characterizes the expression of vascular endothelial growth factor receptor (VEGFR), platelet‐derived growth factor receptor (PDGFR)‐α and PDGFR‐β in canine intranasal carcinomas. Histological samples from 187 dogs were retrieved. Immunohistochemistry was performed using commercially available antibodies. Expression of rTKs was classified into weak, moderate or intense and additionally recorded as cytoplasmic, membranous, cytoplasmic‐membranous, nuclear or stromal. VEGFR was expressed in 158 dogs with predominantly moderate expression (36.9%) and a cytoplasmic‐membranous expression pattern (70.9%). PDGFR‐α was detected in 133 with predominantly weak expression (57.9%) and cytoplasmic pattern (87.9%). PDGFR‐β was identified in 74 patients with a predominantly moderate expression (17.6%) and cytoplasmic expression pattern (63.5%). Co‐expression of rTKs was common. These results confirm expression of VEGFR, PDGFR‐α and PDGFR‐β in canine intranasal carcinomas and support the utility of TKIs.     

Tachypnea and Antipyresis in Febrile Horses after Sedation with α2‐Agonists

Background: Signs of tachypnea after sedation of febrile horses with α₂‐agonists have been noted previously but have not been further investigated. Objectives: To examine the effects of xylazine and detomidine on respiratory rate and rectal temperature in febrile horses and to investigate if either drug would be less likely than the other to cause changes in these variables. Animals: Nine febrile horses and 9 healthy horses were included in the study. Methods: Horses were randomly assigned to sedation with xylazine 0.5 mg/kg or detomidine 0.01 mg/kg. Heart rate and respiratory rate were recorded before sedation and at 1, 3, and 5 minutes after injection. Hourly measurements of rectal temperature were performed starting before sedation. Results: All febrile horses experienced an episode of tachypnea and antipyresis after sedation. Rectal temperature in the febrile group was significantly lower at 1, 2, and 3 hours after sedation. In several measurements, the decrease was >1°C. Respiratory rate in the febrile group was significantly increased after sedation. All febrile horses were breathing >40 breaths/min and 3 horses >100 breaths/min 5 minutes after sedation. No differences were noted between the 2 treatments. No significant changes in respiratory rate or temperature were noted in the reference group. Conclusions and Clinical Importance: Febrile horses can become tachypneic after sedation with detomidine or xylazine. The antipyretic properties of α₂‐agonists need consideration when evaluating patients that have been sedated several hours before examination.     

The Central Effect of β‐Endorphin and Naloxone on The Biosynthesis of GnRH and GnRH Receptor (GnRHR) in The Hypothalamic‐Pituitary Unit of Follicular‐Phase Ewes

The effects of prolonged, intermittent infusion of β‐endorphin or naloxone into the third cerebral ventricle of follicular‐phase ewes on the expression of genes encoding GnRH and GnRHR in the hypothalamus and GnRHR in the anterior pituitary gland (AP) were examined by an enzyme‐linked immunoabsorbent assay. Activation or blockade of μ‐opioid receptors significantly decreased or increased the GnRH concentration and GnRHR abundance in the hypothalamus, respectively, and affected in the same way GnRHR quantity in the AP gland. The changes in the levels of GnRH and GnRHR after treatment with β‐endorphin as well as following action of naloxone were reflected in fluctuations of plasma LH concentrations. On the basis of these results, it is suggested that β‐endorphinergic system in the hypothalamus of follicular‐phase ewes affects directly or via β‐endorphin‐sensitive interneurons GnRH and GnRHR biosynthesis leading to suppression in secretory activity of the hypothalamic‐pituitary axis.