Use of cabergoline to treat primary and secondary anestrus in dogs

OBJECTIVE: To determine whether cabergoline would be safe and effective for induction of estrus in dogs with primary or secondary anestrus. DESIGN: Prospective case series. ANIMALS: 6 privately owned otherwise healthy pure-bred dogs with primary or secondary anestrus. PROCEDURE: Dogs were treated with cabergoline (5 microg/kg [2.3 microg/lb], p.o., q 24 h) until 2 days after the onset of proestrus. Follicular development was assessed by means of cytologic examination of vaginal smears; ovulation was assessed by measuring serum progesterone concentration 3 weeks after the onset of estrus. Five bitches were mated during behavioral estrus. RESULTS: All dogs had normal estrus periods, and all 5 dogs that were mated whelped normal litters. Mean duration of cabergoline treatment was 16 days. None of the dogs had any adverse effects associated with cabergoline administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of cabergoline is safe and effective for treatment for primary and secondary anestrus in dogs.     

Evaluation of different hormonal treatments on oestral and ovarian responses in Moroccan Beni Arouss goats during anoestrus and breeding season

The efficacy of eight combinations of fluorogestone acetate (FGA, 20 or 40 mg as intravaginal device during 11 days), equine chorionic gonadotropin (eCG, 300 or 500 UI injected 48 hr before FGA removal) and prostaglandin F_2α (cloprostenol, 0 or 50 μg injected 48 hr before FGA removal) aiming at induction and synchronization of oestrus and ovulation was evaluated during the anoestrus season in spring and during the breeding season in autumn in adult Beni Arouss goats. Oestrous behaviour was recorded between 12 and 60 hr after FGA removal. Blood samplings allowing to assess onset of the pre‐ovulatory LH surge and increase of progesterone as sign of an active corpus luteum were performed, respectively, between 20 and 60 hr and 3, 5, 8 and 15 days after FGA removal. No season‐related differences (spring vs. autumn) were observed for oestrous response (95% vs. 93%), pre‐ovulatory LH surge (94% vs. 84%) and luteal response after 3–8 and 11–15 days post‐treatment (respectively 92% vs. 66% and 92% vs. 98%). The onset of oestrus (21 [13–53] vs. 32 [12–54] hr) and LH surge (26 [20–60] vs. 38 [22–60] hr) occurred significantly later in autumn. FGA (40 vs. 20 mg) in autumn significantly delayed the onset of oestrus (36 [16–54] vs. 23 [12–47] hr) and LH surge (44 [26–58] vs. 33 [22–60] hr). Significant treatment‐related differences were recorded for onset of LH surge (earliest for 20 mg FGA, 300 IU eCG, 50 μg PGF_2α) and onset of luteal phase (latest for 40 mg FGA, 300 IU eCG, 50 μg PGF_2α). In conclusion, the hormone combinations tested appeared equally effective in terms of oestrous and ovulation rates. Season has influenced significantly the onset of oestrus and LH surge, and the high dose regimen of FGA delayed the ovarian response in autumn.     

Changes in luteinizing hormone pulse frequency and prolactin levels in bitches in response to estrus induction by cabergoline-its cases where it is delayed to induce estrus

The effect of estrus induction by cabergoline on gonadotropin and steroid hormone responses was examined in anestrous bitches. Eleven beagles were used in the study; seven were included in the estrus induction group and four were included in the spontaneous estrus group. Cabergoline was orally administered to the estrus induction group at 5 µg/kg once daily for four weeks, or until hemorrhagic discharge was detected. The inter-estrus interval in the estrus induction group was significantly shorter than the previous estrus interval. Bitches that showed proestrus within four weeks of treatment showed increased luteinizing hormone (LH) pulse frequency and, subsequently, increased estradiol (E₂) levels. Prolactin (PRL) levels declined promptly after treatment, except in one bitch that did not show proestrus during the cabergoline treatment period. There was a significant correlation between the time to proestrus induction and the reduction in PRL levels. A positive correlation was found between the LH levels two weeks after cabergoline administration and PRL reduction. This study demonstrates that an abrupt reduction in PRL is likely to be important for initiation of estrus in bitches. A reduction in PRL indirectly leads to an increase in LH pulse frequency, which regulates follicular development in bitches. However, if the period from the end of the previous estrus to the cabergoline treatment is short, it may take some time to show proestrus without increasing E₂ levels, even if the LH level increases after cabergoline administration.     

Effect of restricted suckling on milk yield,composition and flow,udder health,and postpartum anoestrus in grazing Holstein cows

The effect of restricted suckling on milk yield and composition, udder health, and postpartum anoestrus in dairy cows in pasture-based systems, was studied in 32 Holstein multiparous cows and their calves. At calving, each cow–calf pair was randomly assigned to one of two treatments: restricted suckling (RS) of the cows by her own or another calf, twice daily for 30 min or artificial rearing (AR) of the calves with milk obtained from the bulk tank, offered twice a day in buckets. Treatments were applied until week 8 after calving. The diet of the cows consisted of direct grazing in improved pastures, corn silage and a commercial concentrate which was offered at milking. Milk production and composition, udder health, body condition score of the cows, body weight and milk intake of the calves were measured weekly, and the first postpartum ovulation was determined three times a week by ovarian ultrasonography. Cows with RS management had a lower machine-milked milk yield (17.9 vs. 24.8 kg/d), a lower fat percentage (3.21 vs. 4.11%) and 4% fat-corrected milk yield (16.2 vs. 25.7 kg/d), and also a lower average milk flow (1.35 vs. 1.76 kg/min) than cows in the AR treatment. There was no effect of treatment on milk protein percentage or udder health as measured by milk electrical conductivity. The interval from calving to first postpartum ovulation was shorter in the AR cows than in the RS cows (18.5 vs. 21.8 days). The RS calves consumed more milk (7.2 vs. 5.4 kg/d), gained more body weight (0.813 vs. 0.656 kg/d), and had a higher body weight at weaning (84.3 vs. 73.3 kg) than AR calves. Restricted suckling of grazing dairy cows had a negative effect on machine-milked milk yield, fat percentage and 4% fat-corrected milk yield, but had no effect on udder health or on improved weight gain and body weight at weaning of the calves.     

Effects of dietary scFOS on immunoglobulins in colostrums and milk of bitches

Fructo-oligosaccharides (scFOS) are prebiotic ingredients that improve protection against pathogens probably through promoting the growth of gastrointestinal bacteria-like Bifidobacteria and Lactobacilli: this stimulation may lead to a better development of immune repertoire and/or stimulation of the local immune response. According to the existence of the immune entero-mammary link, we were wondering if the dietary supplementation with scFOS could enhance the mucosal immunoglobulin level in mammary secretions. Results in this study show that bitches supplemented with scFOS exhibit higher colostrum and milk IgM content without concomitant effect on IgG1, IgG2 and IgA. In addition, intranasally immunized puppies exhibited a trend to higher Bordetella bronchiseptica-specific IgM immune response. The dietary supplementation with scFOS increased the IgM level in colostrums and milk of bitches by mechanisms which remain to be elucidated.     

Thyroid hormones and metabolic rate during induction of Vitamin B12 deficiency in goats

Vitamin B₁₂ deficiency was induced in 15 small East African goats by feeding cobalt deficient ^{Chloris guyana} hay (containing 0.02 mg of Co/kg dry matter) over a 25week experimental period. Cobalt was supplemented as an oral drench to supply 0.3 g of Co/goat/week to 15 treated goats. At intervals of 3–4 weeks, serum concentrations of Vitamin B₁₂ total thyroxine (TT₄), free tetra-iodothyronine (FT₄) and free tri-iodothyronine (FT₃) were determined by radioimmunoassay, while the rate of resting metabolism was determined by measuring the goats' rate of oxygen consumption.

Serum Vitamin B₁₂ concentration was significantly higher (p<0.01) in cobalt-treated (289.6 ± 40.76 pg/ml) than in control (142.8 ± 28.27 pg/ml) goats. The mean serum TT₄ concentration was signifieantly (p<0.01) higher in control (59.0 ± 1.70 nmol/l) than in cobalt-treated (51.6 ± 2.45 nmol/l) goats. However, the levels of FT₄, FT₃ and the rate of resting metabolism were unaffected by the goats' cobalt status. Furthermore, the goats did not lose weight or become anaemic.     

The clinical use of the neuromuscular blocking agent rocuronium in dogs

Objective The aim of this study was to characterize the onset and duration of action of the aminosteroid muscle relaxant rocuronium in dogs under clinical conditions. Study design Prospective single dose trial. Animals Twenty‐three dogs aged between 6 months and 12 years, weighing between 5.5 and 61.5 kg admitted to the University of Liverpool Small Animal Hospital between January and March 2000, and undergoing elective surgical procedures under general anaesthesia. Materials and methods Following induction of general anaesthesia, neuromuscular function was evaluated using train‐of‐four (TOF) stimulation. An initial dose of 0.4 mg kg^?1 rocuronium was administered intravenously (IV) and neuromuscular blockade was monitored by visually assessing the number of responses (twitches) to TOF stimulation (train‐of‐four count: TOFC). Incremental doses of 0.16 mg kg^?1 rocuronium were administered as indicated, when at least two twitches of the TOFC had returned. Results Rocuronium (0.4 mg kg^?1) abolished all responses to TOF stimulation in all dogs. The mean time to onset of neuromuscular blockade (complete abolition of all twitches) was 98 ± 52 seconds. Neuromuscular blockade (absence of all twitches to return of all four) lasted 32.3 ± 8.2 minutes. Incremental doses of 0.16 mg kg^?1 had a mean duration of action of 20.8 ± 4.9 minutes and up to seven increments were shown to be noncumulative. The effects of rocuronium were readily antagonized with neostigmine and atropine. Small transient increases in arterial blood pressure, which occurred in three dogs after the administration of rocuronium, were the only cardiovascular side‐effects observed. Conclusions Rocuronium is an effective nondepolarizing neuromuscular blocking agent in the dog, with a rapid onset of neuromuscular block after intravenous administration and an intermediate duration of action. Clinical relevance Rocuronium produced a neuromuscular block with similar characteristics to those obtained with vecuronium, thus apparently offering little advantage over vecuronium. However, its availability in aqueous solution and a longer shelf‐life increases convenience.     

The use of the nondepolarizing neuromuscular blocking drug cis-atracurium in dogs

Objective This clinical trial attempted to evaluate the potency, onset and duration of action of cis‐atracurium in dogs. Animals Twenty dogs aged between 1 and 15 years and weighing between 15 and 85 kg admitted for a variety of elective, surgical procedures under general anaesthesia. Materials and methods Following induction of general anaesthesia, the effects of an intravenous loading dose of cis‐atracurium (0.1 mg kg^?1) were evaluated by counting visual responses to train of four (TOF) nerve stimulation. Incremental doses of 0.02 or 0.04 mg kg^?1 cis‐atracurium were administered when the first of four responses to TOF stimulation was present. Results An initial dose of 0.1 mg kg^?1 eliminated all four TOF responses in 18 out of 20 dogs. The same dose, repeated 10 minutes later in two animals in which blockade was incomplete, abolished all responses. In dogs receiving 0.1 mg kg^?1 cis‐atracurium neuromuscular blockade lasted 27.2 ± 9.3 minutes. Up to six incremental doses were given in individual animals; incremental doses appeared to be noncumulative. No untoward side‐effects were observed with the use of this drug. There was considerable variation between individuals in response to cis‐atracurium. Conclusions Cis‐atracurium is an effective neuromuscular blocking agent in the dog, although its potency varies. Clinical Relevance Further studies are required to determine whether observed differences in potency are related to age, breed or sex. Cis‐atracurium may prove useful in dogs with impaired renal and or hepatic function.     

Unilateral uterine torsion secondary to an inflammatory endometrial polyp in the bitch

A 9-year-old bitch was presented because of lethargy and abdominal distension. Abdominal ultrasound revealed an enlarged, fluid-filled uterus and associated mass. Subsequent exploratory laparotomy revealed unilateral uterine torsion involving the mass. Recovery following ovariohysterectomy was uneventful and the histopathological diagnosis was of a benign endometrial inflammatory polyp. Reports of uterine torsion in the English-language literature are reviewed to identify factors associated with the incidence of uterine torsion. The aetiology of the cystic endometrial hyperplasia/pyometra complex and its possible role in the development of inflammatory polypoid lesions in the bitch is also discussed.     

河南省郑州市某宠物医院2例犬巴贝斯虫病的诊治

犬巴贝斯虫病是一种由硬蜱传播的犬血液寄生虫病,以春、夏季节多发,患病犬出现高热、黄疸、尿液发红、严重贫血、消瘦、精神萎靡等临床症状。选取河南省郑州市某宠物医院的2例犬巴贝斯虫病例进行分析,总结了犬巴贝斯虫病的诊治方法。     

A Pharmacokinetic Comparison of Meloxicam and Ketoprofen following Oral Administration to Healthy Dogs

Ketoprofen (KTP) and meloxicam (MLX) are non-steroidal anti-inflamatory drugs used extensively in veterinary medicine. The pharmacokinetics of these drugs were studied in eight dogs following a single oral dose of 1 mg/kg of KTP as a racemate or 0.2 mg/kg of MLX. The concentrations of the drugs in plasma were determined by high-performance liquid chromatography (HPLC). There were differences between the disposition curves of the KTP enantiomers, confirming that the pharmacokinetics of KTP is enantioselective. (S)-(+)-KTP was the predominant enantiomer; the S:R ratio in the plasma increased from 2.58 +/- 0.38 at 15 min to 5.72 +/- 2.35 at 1 h. The area under the concentration time curve (AUC) of (S)-(+)-KTP was approximately 6 times greater than that of (R)-(-)-KTP. The mean (+/- SD) pharmacokinetic parameters for (S)-(+)-KTP were characterized as Tmax = 0.76 +/- 0.19 h, Cmax = 2.02 +/- 0.41 microg/ml, t1/2el = 1.65 +/- 0.48 h, AUC = 6.06 +/- 1.16 microg.h/ml, Vd/F = 0.39 +/- 0.07 L/kg, Cl/F = 170 +/- 39 ml/(kg.h). The mean (+/- SD) pharmacokinetic parameters of MLX were Tmax = 8.5 +/- 1.91 h, Cmax = 0.82 +/- 0.29 microg/ml, t1/2lambda(z) = 12.13 +/- 2.15 h, AUCinf = 15.41 +/- 1.24 microg.h/ml, Vd/F = 0.23 +/- 0.03 L/ kg, and Cl/F = 10 +/- 1.4 ml/(kg.h). Our results indicate significant pharmacokinetic differences between MLX and KTP after therapeutic doses.     

The effect of the use of norethisterone acetate to control oestrus in Greyhound bitches on subsequent racing performance and fertility

It has been shown that norethisterone acetate (Norlutin-A—Parke-Davis), when used for a 4-week course starting in prooestrus, is capable of controlling oestrus in Greyhound bitches (Prole, 1974). A study of their racing performance will give some measure of objective assessment of the effect of this progestagen. The subsequent breeding history of some of the bitches is also discussed.
Résumé. On a montré que Norlutin-A (Norlutin-A — Parke-Davis), est capable d'avoir contrôle sur l'œstrus chez les lévriers femelles (Prole, 1974) quand on l'utilise pour un traitement de quatre semaines, commençant par le prœstrus. Une étude de leur performance à la course donnera quelque mesure de l'évaluation objective de l'éffet de ce progestagène. On discute aussi des cas subséquents d'élevage de qualeques-unes de ces femelles.
Zusammenfassung. Es hat sich erzeigt, dass Norlutin-A (Norlutin-A — Parke-Davis) wenn in einer vier Wochen langen Behandlungserrie angewendet, fähig ist Oestrus in Windhündinnen zu kontrollieren (Prole 1974). Eine Studie ihrer Rennleistung gibt einen Massstab von objectiver Schätzung über die Wirkung von diesem Progestagen. Der spätere Zuchtverlauf von einigen dieser Hündinnen wird ebenfalls diskutiert.