Hypocalcaemia due to nutritional calcium deficiency and hypoparathyroidism in an adult dog

A 13-year-old intact male poodle had suffered periodic tetanic crises for two months. It was cachectic and moderately dehydrated, and during the crises blindness, a stiff gait and behavioural changes were observed. Routine haematological and biochemical profiles showed that it was severely hypocalcaemic, with a corrected plasma calcium concentration of 1.13 mmol/litre (reference range 2.25 to 3 mmol/litre). The dog was fed a home-made diet composed of chicken and basmati rice cooked with a soup bouillon cube; an analysis of its daily allowance indicated that the dog was generally malnourished and received only 0.222 g of calcium per day rather than the 0.6 g it required. In addition, the dog had a low blood concentration of parathyroid hormone of 12 ng/litre (reference range 20 to 80 ng/litre). Supplementing the dog with calcitriol for four days and correcting its diet increased its blood calcium to the lower part of the reference range and resolved the clinical signs, although its parathyroid hormone concentration was still low one year later.     

Constraints under organic farming on French sheepmeat production: a legal and economic point of view with an emphasis on farming systems and veterinary aspects

Ovine meat production in France, which is continually regressing due to economic difficulties, is based on two main production systems. The first system is located in plains in which one part of the lambs born in the spring are fed grass, and the other part of the lambs are from out of the season parturitions following hormonal treatments and are fattened in sheep houses. The second system is represented by farms in the mountains using hardy breeds which have a natural faculty for out of the season breeding and whose lambs are fattened indoors, whatever the season of birth. Amongst the sanitary problems encountered, parasitism in particular of young animals, is crucial, especially for farms on plains practising grass fattening. These farmers systematically use conventional anthelmintic treatments, in particular against Moniezia and Strongyles. With organic farming, the limited number of conventional anthelmintic treatments is a strong constraint, especially for the management of young grass-fed animals. A study of 10 organic farming farms or farms converting to organic farming (six in the mountains and four in the plains) showed that the size of these farms is inferior to that of conventional ones and have technical performances which are comparable to the average with 20 to 30% extra over-prices on lamb sales. Despite this, the gross margins per ewe in organic farming are equal to the average of those for conventional farms. This is due to the high consumption of concentrate at a high cost (50 to 100% greater than that for conventional farms). Finally, to prevent sanitary risks, certain organic farmers use important amounts of feed supplements containing phytotherapy products whose costs burden a part of the financial results of the farm. On the contrary, other organic farmers are able, by adapting breeding and grazing managements, to significantly decrease animal health costs without increasing feed supplements nor decreasing zootechnical performances.     

The effects of induced parturition on the incidence of clinical disease and mortality in dairy cows from commercial herds in south-western Victoria

SUMMARY The effects of induced parturition on clinical disease and mortality of cows were studied in 51 winter-calving, pasture-fed, dairy herds in south-western Victoria. Parturition was induced when most cows were between 27 and 35 weeks of pregnancy. Control groups were selected from herdmates that were not induced to calve. The incidence of retained placenta was much greater among induced cows of all ages. The proportion of cows affected by any clinical disease other than retained placenta, and the incidence of mortality were much greater after induction among cows aged over 6 years but not among cows aged 3 to 6 years.     

Effect of Planting Date and Thermal Energy Intensity on Rate of Phosphorus and Potassium Accumulation by Maize (Zea mays L.)1

The effect of planting date and thermal energy intensity (TEI) on the rate of phosphorus (P) and potassium (K) accumulation by maize from a Hamerly clay loam soil (Aerie Calciaquoll) was examined with and without supplemental irrigation. Soil- and air-TEI expressed as growing degree days per day (GDD d^?1) were determined from hourly temperature measurements taken within each plot. Net K accumulation occurred during the vegetative growth stage, reached maximal rates of about 62.2 to 91.4 mg plant^?1 day^?1, and attained maximal accumulations ranging from about 1.15 to 2.3 g plant^?1. Accumulation of P occurred during vegetative and reproductive growth stages, reached maximal rates of about 4.6 to 10.3 mg and 6.5 to 12.1 mg plant^?1 day^?1, respectively and maximal accumulations of 0.175 to 0.27 g and 0.11 to 0.26 g plant^?1, respectively. During vegetative growth, K and nitrogen (N) accumulation characteristics were closely correlated with about 2 moles of N accumulated per mole of K. Maximal accumulation of K (and N) consistently preceded that of P by about 5.2 to 8.3 days and that of the plant dry weight by about 15.9 to 20.5 days during the vegetative growth stage. Time required to reach maximal accumulation during the reproductive growth stage, t_r followed the order N < P < dry weight for early plantings and followed the order N < P < dry weight for delayed plantings. Time coefficients for K and P accumulation were correlated closely with soil-TEI, but models of each coefficient relied on unique combinations of TEI. Time coefficients for dry matter accumulation were apparently unrelated to soil- or air-TEI.     

胚胎移植技术的应用及其发展

动物胚胎移植首次成功(Heape 1891)距今已近一百年了。在这期间,又有多种动物胚胎移植试验成功,技术也不断改进。但是,进展较大的还是近二十年间。1981年Betterid-ge总结了胚胎移植历史,列出了13种动物胚胎移植首次成功的时间和试验者[兔1891Heape;大鼠1933 Nicholas;绵羊1934Warwick等;山羊(自身重移植)1934Warwick等;小鼠1942 Fekete＆Lit-tle;奶牛(流产)1949 Umbaugh;山羊1949 Warwick＆Berry;奶牛1951Willett等;猪1951 Kvasnickii;奶牛     

An update on Reproductive Technologies with Potential Short-Term Application in Pig Production

Over the past decade, there has been an increase in the development and/or in the improvement of emerging reproductive technologies in pigs. Among emerging reproductive technologies with potential short-term application in pig production are: artificial insemination with low number of spermatozoa, cryopreservation of spermatozoa and embryos, sperm sexing, and non-surgical embryo transfer. The following review will give emphasis to recent advancements in these reproductive technologies that are starting to show possibilities of serious applications under field conditions.     

Retained Functional Integrity of Bull Spermatozoa after Double Freezing and Thawing Using PureSperm® Density Gradient Centrifugation

The main aim of this study was to compare the motility and functional integrity of bull spermatozoa after single and double freezing and thawing. The viability and morphological integrity of spermatozoa selected by PureSperm density gradient centrifugation after cryopreservation of bovine semen in two commercial extenders (Experiment 1) and the function of bull spermatozoa before and after a second freezing and thawing assisted by PureSperm selection (Experiment 2) were examined. On average, 35.8 +/- 12.1% of sperm loaded onto the PureSperm density gradient were recovered after centrifugation. In Experiment 1, post-thaw motility and acrosome integrity were higher for spermatozoa frozen in Tris-egg yolk extender than in AndroMed, whether the assessments were made immediately after thawing [80.4 +/- 12.7 vs 47.6 +/- 19.0% motile and 78.8 +/- 8.3 vs 50.1 +/- 19.5% normal apical ridge (NAR), p < 0.05] or after preparation on the gradient (83.3 +/- 8.6 vs 69.4 +/- 15.9% motile and 89.5 +/- 7.2 vs 69.1 +/- 11.4% NAR, p < 0.05). For semen frozen in Tris-egg yolk extender, selection on the PureSperm gradient did not influence total motility but significantly improved the proportion of acrosome-intact spermatozoa. After the gradient, both the total motility and percentage of normal acrosomes increased for spermatozoa frozen in AndroMed (Minitüb Tiefenbach, Germany). In Experiment 2, there was no difference in sperm motility after the first and second freeze-thawing (82.9 +/- 12.7 vs 68.8 +/- 18.7%). However, the proportion of acrosome-intact spermatozoa was significantly improved by selection through the PureSperm gradient, whether measured by phase contrast microscopy (78.9 +/- 9.7 vs 90.4 +/- 4.0% NAR, p < 0.05) or flow cytometry (53.4 +/- 11.7 vs 76.3 +/- 6.0% viable acrosome-intact spermatozoa, p < 0.001). The improvement in the percentage of spermatozoa with normal acrosomes was maintained after resuspension in the cooling extender and cooling to 4 degrees C (88.2 +/- 6.2) and after re-freezing and thawing (83.6 +/- 6.56% NAR). However, flow cytometric assessment of the sperm membranes revealed a decline in the percentage of viable spermatozoa with intact membranes after the second freezing and thawing compared with after gradient centrifugation (76.3 +/- 6.0% vs 46.6 +/- 6.6%, p < 0.001) to levels equivalent to those obtained after the first round of freeze-thawing (53.4 +/- 11.7% viable acrosome-intact spermatozoa). Sperm movement characteristics assessed by computer-assisted analysis were unaffected in the population selected on the PureSperm gradients but declined after cooling of the selected and extended spermatozoa to 4 degrees C. There was no further change in these kinematic measurements after the cooled spermatozoa had undergone the second round of freeze-thawing. These results demonstrate that bull semen can be frozen and thawed, followed by a second freeze-thawing cycle of a population of spermatozoa selected by PureSperm, with retained motility and functional integrity. This points to the possibility of using double frozen spermatozoa in bovine artificial insemination programmes and to the potential benefits of PureSperm density gradient centrifugation for the application of cryopreserved bull spermatozoa to other biotechnological procedures such as flow cytometric sex sorting followed by re-freezing and thawing.     

Low-Dose Insemination in Pigs: Problems and Possibilities

Low-dose AI procedures are required by the pig industry to efficiently utilize emerging sperm technologies, such as cryopreservation and sex-sorting. Currently, several different procedures for inseminating with a low or very low number of spermatozoa have been described. Deep intrauterine insemination allows the deposition of the spermatozoa in the depth of the uterine horn, allowing a significant reduction in the number of spermatozoa inseminated with maintenance of optimal reproductive performance. Intra-oviductal laparoscopic insemination has been recently applied in pigs. This technique has proved to be applicable with diluted and sex-sorted spermatozoa. This review discusses several problems encountered during the development of deep intrauterine insemination and intra-oviductal laparoscopic insemination of pigs and provides potential solutions for the practical application of both the technologies.