Follicular Dynamics and Oestrous Detection in Thai Postpartum Swamp Buffaloes (Bubalus bubalis)

This study characterized follicular activity and oestrous behaviour from 5 to 9 days post‐calving up to the 4th ovulation postpartum (pp) in 16 multiparous (range 2–7 parities) Thai swamp buffalo cows (Bubalus bubalis), aged 4–12 years and weighing from 432 to 676 kg. Ovarian follicular activity was examined by transrectal ultrasonography (TUS) every morning. Oestrous detection was performed twice daily by direct personal observation of behaviour and for presence of clear cervical mucus discharge and indirectly by video camera recording during 21 h/day. A follicular wave‐like pattern was present before the 1st ovulation leading to short oestrous cycles. Growth rates and maximum diameters of the ovulatory follicles did not differ between the 1st and 4th ovulations. However, growth rate for non‐ovulatory dominant follicles (DF) before the 1st ovulation was lower than for the ovulatory follicle (p < 0.05). In addition, the diameter of all ovulatory follicles (14.3 ± 0.46 mm, n = 39) was significantly larger (p < 0.01) than those of the preceding last but one non‐ovulatory DF (10.8 ± 0.20 mm, n = 5), but similar to the last preceding non‐ovulatory DF diameter (12.92 ± 0.96 mm, n = 14). Short oestrous cycles were most common between the 1st and 2nd ovulations (93.75%, 15/16 cows, 10.2 ± 0.38 days) decreasing in prevalence thereafter (50%, 3/6 buffaloes, 12.0 ± 1.53 days). Oestrous signs were relatively vague around the 1st ovulation pp to become more easily detectable thereafter. This study suggests that properly fed swamp buffaloes could be mated successfully within 2 months pp, at their 2nd spontaneous ovulation, provided oestrous detection is at least performed daily at 06:00–08:00 hour.     

Smooth Muscle Cells of the Bovine Cervical Stroma may have a Secretory, rather than a Contractile Function during Parturition

The bovine cervix contains a large amount of smooth muscle cells distributed over an outer muscular layer and within a stromal layer. The stromal layer exhibits no electromyographic (EMG) activity at parturition. This leads to the question whether the stromal smooth muscle cells of the bovine cervix are prepared to contract with parturition, or whether they have another function. To this end, cervical biopsies were repeatedly taken from 10 pregnant cows at day-185 and -275 of gestation, at spontaneous, uncomplicated calving and at 30 days after calving. The smooth muscle bundles of the stroma were immunohistochemically analysed (n = 5) with regard to their integrity and cellular density, and the degree of staining for connexin-43, smooth muscle actin α (SMA), desmin and vimentin. Additionally, the mRNA expression for connexin-43, SMA, desmin and vimentin was determined with RT-PCR (n = 5). The smooth muscle tissue was arranged in bundles, also at parturition. However, the cellular density of these bundles and the SMA mRNA expression were decreased at parturition. Additionally, the SMA staining and connexin-43 expression and staining remained constant during pregnancy and at parturition. This might indicate that stromal smooth muscle cells are not prepared to contract with parturition, in contrast to the myometrial smooth muscle cells. The smooth muscle cells, stained for SMA, also expressed vimentin, and the proportion of co-expression was increased at day-275 of pregnancy. This suggests that the stromal smooth muscle cells predominantly have a secretory function in cows.     

Vetch toxicosis in cattle grazing Vicia villosa ssp dasycarpa and V benghalensis

SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads.     

Production responses to internal parasite control in dairy cattle

A significant increase in milk production, averaging 164 litres per cow per lactation (a 4.8% increase), was seen after cows infected with gastrointestinal nematodes, paramphistomes and Fasciola hepatica were treated with broad-spectrum anthelmintics. Three hundred and ninety pairs of cows from eight herds with year-round calving were studied. One cow in each matched pair was given 7.5 mg/kg fenbendazole, 7.5 mg/kg levamisole hydrochloride and 15 mg/kg oxyclozanide in March, May and August of one year; the other cow in the pair received no anthelmintic. The number of nematode and trematode eggs was significantly decreased in the faeces of treated cows.     

Plasma Inhibin Levels in Relation to Steroids and Gonadotrophins during Oestrous Cycle in Buffalo

The study was conducted on six Murrah buffalo synchronized and induced to oestrus. An indwelling catheter was placed in the jugular vein of each buffalo 4 days before the expected onset of the oestrus following the induced oestrus and blood samples were collected at 8 h intervals from each animal throughout the oestrous cycle. Plasma immunoreactive inhibin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol-17β and progesterone were estimated by radioimmunoassay to study the variations in the peripheral levels of these hormones and their inter-relationships in order to elucidate the feedback systems controlling them during the oestrous cycle of buffalo. Plasma inhibin levels ranged between 391.25 and 631.97 pg/ml during various phases of the oestrous cycle and were found to be higher than reported in cows. Peak LH and FSH levels during oestrus were 38.40 ± 9.21 and 24.04 ± 4.75 ng/ml, respectively and estradiol-17β and progesterone were 19.50 ± 5.51 pg/ml and 0.61 ± 0.25 ng/ml, respectively. The mean plasma inhibin concentration on the day of oestrus was 562.5 ± 18.9 pg/ml. Levels of FSH in the plasma showed three mid-cycle elevations which corresponded to comparatively lower inhibin and elevated estradiol-17β levels during the same period. From this observation it was deduced that both inhibin and estradiol-17β have a feed-back regulatory effect on FSH secretion in buffalo.     

Congenital Abnormality of the Vagina Complicated by Haemato‐Pyocolpos in a 1‐Year Labrador Retriever

A 1‐year‐old female Labrador retriever was referred with a few days history of haematic‐like vulvar discharge. Physical examination, vaginal inspection and palpation did not reveal any remarkable finding. Transabdominal ultrasound showed echogenic fluid accumulation in the vagina suggesting haemato‐pyocolpos. An exploratory laparotomy was performed: a well‐delimited ectasic vagina was identified. Ovariohysterectomy and partial vaginectomy and vaginoplasty were performed to spay the bitch and to remove the ectasic vagina. Post‐operative recovery and 12‐month follow‐up were uneventful. Clinical, morphological and histological findings were consistent with a congenital abnormality of the muscular layer of the vagina complicated by haemato‐pyocolpos. The disorganization of the vaginal tunica muscularis may have acted as locus minoris resistentiae in the vaginal wall. The organ was dilated and atonic due to the gradual accumulation of physiological fluids complicated by an overgrowth of genital bacteria. This congenital disorder has to be taken into account as differential diagnosis of haemato‐pyocolpos with vaginal discharge in young bitches.     

Comparative evaluation of metallic skin staples or polypropylene sutures for primary closure of teat wounds in sheep

ABSTRACT

Aims

To compare stainless steel staples and polypropylene suture material for primary closure of wounds after teat amputation in ewes and to assess progress of healing in the presence or absence of intramammary infection (IMI).     

Effects of Superovulation with oFSH and Norgestomet/GnRH‐Controlled Release of the LH Surge on Hormone Concentrations,and Yield of Oocytes and Embryos at Specific Developmental Stages

The objective of this study was to evaluate a new superovulation procedure with oFSH after temporary suppression of the endogenous LH surge by norgestomet followed by administration of GnRH, to collect bovine oocytes and embryos at specific developmental stages. Since 1999, our research group applies this superovulation procedure with controlled release of the endogenous LH surge. The objective of this study is to verify if this procedure is reliable for collection of oocytes and embryos at specific time points of development and if it produces a sufficient number of both oocytes and embryos of good quality. This procedure was validated regarding to hormonal characteristics, superovulatory response and both oocyte and embryo yield at different times of in vivo development. The results demonstrate that the procedure used to control the occurrence of the pre‐ovulatory LH surge was effective in 92% of the animals (n = 238) and even in 99% of the animals the oocytes and embryos were collected at the intended stage of development. The superovulatory response and both oocyte, embryo yield and quality were similar to the average yield in Europe reported by Association Européenne de transfert embryonnaire (AETE). In conclusion, this superovulation procedure provides a valid tool to collect oocytes and embryos at specific time points of development.