Pregnancies from bovine oocytes matured and fertilized in vitro

Production of transgenic animals and embryo cloning are only a few examples of new biotechnological methods applied to animal embryos. All these techniques require large amounts of oocytes and early embryos. In many laboratory animals, embryos matured and fertilized in vivo are easily obtained, but with larger domestic species it requires laborious surgical procedures and the number of embryos obtained remains relatively small (Bracken et al. 1982). The in vitro maturation of follicular oocytes derived from slaughterhouse ovaries and their in vitro fertilization provides large numbers of oocytes and embryos with considerably less effort. The final proof of the success in the in vitro maturation and fertilization procedure is the birth of healthy progeny. Also the normal preimplantation development of the embryos gives useful information about the efficiency of the method employed.     

Resistance to drought of mollusks of the genus Bulinus, vectors of human and animal trematode infections in Senegal. II. Study under natural conditions in the North-Sudan area. Ecology and resistance to drought of Bulinus umbilicatus and B. senegalensis

The authors report on the results of a 2-year study on the ecology and resistance to drought of B. umbilicatus and B. senegalensis on 3 temporary ponds in the North-Sudan area (region of Tambacounda, Senegal). The variations in some abiotic factors like the temperature and the pH of water do not seem to have a strong influence on the ecology while rainfall has a great importance on the distribution and the density of molluscs. As a fact, the quantity of water and the drying out period of these ponds depend upon rain factors which rule the existence and the survival of the malacological fauna. In the second part of the rainy season, the population reaches its maximum, i.e., during the reproduction period. Monthly observations show that the relative abundance of B. umbilicatus is higher than that of B. senegalensis. These ponds are dry during 6 to 8 months per year. However the populations of molluscs regenerate regularly, a fact which presupposes a certain ability to resist drought. Some come through this period successfully, but the middle-sized ones (7 to 9.9 mm) resist better than others (70 to 80 per cent of the population). Immediately after the first rains they resume their activity and lay intensively in order to reconstitute the population. B. umbilicatus and B. senegalensis are potential intermediate hosts for human and animal trematode infections, but in the studied region only B. umbilicatus intervenes in the transmission of S. haematobium and S. curassoni which occurs between September and November. Under natural Sahel conditions the epidemiological cycle is short and everything happens within 4 to 6 months with the regeneration and the growth of the population of molluscs, its infestation and the transmission of trematode infections. The ecological behaviour of these molluscs in the North-Sudan region is very important in the epidemiology of human and animal trematode infections and requires a new controlling strategy. The destruction of molluscs is more effective and more economic at the end of the rain season, which is the beginning of the drying of ponds, a period in which they concentrate in the residual water pools.     

Prevalence of Cryptosporidium sp in equids in Louisiana

In 1985, 22 pony foals reared in a helminth-free environment were tested daily for oocysts of Cryptosporidium sp by use of fecal flotation. Oocysts were found in all foals. Oocysts were first observed in feces collected from foals 9 to 28 days after birth. The mean period of oocyst shedding was 10 days and ranged from 2 to 18 days in individual foals. Diarrhea was observed in 14 of 22 (64%) foals and began before the period of oocyst shedding. Fecal samples also were examined for other infective agents. Salmonella poona was isolated from 1 foal that did not have diarrhea, and coronavirus particles were observed in the feces of 2 foals with diarrhea. Cryptosporidium sp oocysts also were observed in feces of 2 of 17 Thoroughbred foals, 3 of 14 Quarter Horse foals, and 3 of 26 pony foals reared on pastures with their dams. Samples from pasture-reared foals were collected at irregular intervals. Of the 11 Cryptosporidium-positive fecal samples collected from pastured foals, 2 were from foals with diarrhea. A similar survey was conducted during the 1986 foaling season, using the same procedures. Examination of 300 samples from 58 Quarter Horse, Arabian, and pony foals did not detect oocysts. Daily examination of feces from 10 pony foals reared under helminth-free conditions for 30 days also failed to detect Cryptosporidium oocysts.     

Resumption of postpartum luteal function of primiparous, suckled beef cows exposed continuously to bull urine

The objective of this experiment was to determine if continuous exposure to bull urine alters resumption of ovarian cycling activity of primiparous, suckled beef cows. We tested the hypotheses that interval from urine exposure to resumption of luteal activity and proportions of cows that resume luteal activity by the end of the urine-exposure period do not differ between cows exposed to mature bull urine or steer urine. Thirty-eight Angus (A) x Hereford (H) cows, 4 mature A x H bulls and four 10-mo-old A x H steers, were used in this study. Cows were stratified by calving date, cow BW, calf BW, calf sex, dystocia score, and BCS; fitted with a controlled urine delivery device 2 wk before the start of treatments; and assigned randomly to be exposed continuously (24 h/d) to bull urine (n = 19) or steer urine (n = 19) beginning 40 d after calving. Urine was collected from bulls and steers every third day of the experiment. Blood samples were collected from cows starting on d 0 and every third day thereafter until the end of the exposure period (approximately 64 d). Likewise, controlled urine delivery devices were filled and refilled on the same schedule. Neither interval from urine exposure to resumption of luteal activity nor proportions of cows that resumed luteal activity during the urine-exposure period differed between cows exposed to bull urine or steer urine. We concluded that continuous exposure to mature bull urine does not affect resumption of luteal activity of primiparous, suckled beef cows.     

Genetic partitioning of variation in ovulatory follicle size and probability of pregnancy in beef cattle

The objectives of this research were to partition variation in ovulatory follicle size into genetic and nongenetic components and to assess the utility of ovulatory follicle size as an indicator trait associated with reproductive success in beef cattle. Data were collected during the years 2002 to 2005 from 780 beef females that ranged in age from 1 to 12 yr (mean of 2.4 observations per female). Data were analyzed with a multiple trait Gibbs sampler for animal models to make Bayesian inferences from flat priors. A chain of 500,000 Gibbs samples was thinned to every 200th sample to produce a posterior distribution composed of 2,500 samples. Heritability estimates (posterior mean +/- SD) were 0.16 +/- 0.03 for follicle size and 0.07 +/- 0.02 and 0.02 +/- 0.01 for pregnancy rate as a trait of the female and service sire, respectively. Posterior means of genetic correlations were all <0.10, with 0.00 contained within the respective 90% probability density posterior intervals. Results indicate that whereas follicle size is of greater heritability than pregnancy rate, its usefulness to improve reproductive rate is greatest as an ancillary phenotype in multiple trait selection.     

Pemphigus foliaceus in 91 dogs

A retrospective study of 91 dogs with pemphigus foliaceus was performed. Clinical signs of the disease included crusts (n=79), pustules (n=36), and alopecia (n=33). Lesions were most common on the trunk (n=53), inner pinnae (n=46), face (n=37), and foot pads (n=32). Cytological evaluation revealed acantholytic keratinocytes in 37 of 48 dogs. Results of combination treatment with prednisolone and azathioprine were comparable to results with prednisolone therapy alone. More than half of the dogs achieved remission with appropriate therapy, and another 25% significantly improved.     

Effects of supplementing pregnant heifers with methionine or melatonin on the anatomy and other characteristics of their lateral hind claws

Three groups of four primiparous Holstein-Friesian heifers were fed throughout pregnancy either a control diet or that diet supplemented with either 5 to 6 g per day of rumen-protected intestinally available methionine or 25 mg melatonin. They were euthanased three days after calving. The dietary supplements had no effect on the impression hardness or the concentrations of cysteine and methionine in samples of claw horn collected from a range of sites, or on the areas of erosion in the sole and heel. Significant differences were recorded for the hardness of the horn in the order wall >sole >heel. These differences were associated with higher concentrations of cysteine and lower concentrations of methionine in samples of horn from the dorsal wall than in samples from the prebulbar region of the sole. There were no significant differences attributable to the dietary supplements in the soft tissue anatomy of the solear dermis and epidermis.     

The effect of ingredients in dry dog foods on the risk of gastric dilatation-volvulus in dogs

Using dry dog food label information, the hypothesis was tested that the risk of gastric dilatation-volvulus (GDV) increases with an increasing number of soy and cereal ingredients and a decreasing number of animal-protein ingredients among the first four ingredients. A nested case-control study was conducted with 85 GDV cases and 194 controls consuming a single brand and variety of dry food. Neither an increasing number of animal-protein ingredients (P=0.79) nor an increasing number of soy and cereal ingredients (P=0.83) among the first four ingredients significantly influenced GDV risk. An unexpected finding was that dry foods containing an oil or fat ingredient (e.g., sunflower oil, animal fat) among the first four ingredients were associated with a significant (P=0.01), 2.4-fold increased risk of GDV. These findings suggest that the feeding of dry dog foods that list oils or fats among the first four label ingredients predispose a high-risk dog to GDV.     

Development and psychometric testing of an instrument designed to measure chronic pain in dogs with osteoarthritis

OBJECTIVE: To develop and psychometrically test an owner self-administered questionnaire designed to assess severity and impact of chronic pain in dogs with osteoarthritis. SAMPLE POPULATION: 70 owners of dogs with osteoarthritis and 50 owners of clinically normal dogs. PROCEDURES: Standard methods for the stepwise development and testing of instruments designed to assess subjective states were used. Items were generated through focus groups and an expert panel. Items were tested for readability and ambiguity, and poorly performing items were removed. The reduced set of items was subjected to factor analysis, reliability testing, and validity testing. RESULTS: Severity of pain and interference with function were 2 factors identified and named on the basis of the items contained in them. Cronbach's alpha was 0.93 and 0.89, respectively, suggesting that the items in each factor could be assessed as a group to compute factor scores (ie, severity score and interference score). The test-retest analysis revealed kappa values of 0.75 for the severity score and 0.81 for the interference score. Scores correlated moderately well (r = 0.51 and 0.50, respectively) with the overall quality-of-life (QOL) question, such that as severity and interference scores increased, QOL decreased. Clinically normal dogs had significantly lower severity and interference scores than dogs with osteoarthritis. CONCLUSIONS AND CLINICAL RELEVANCE: A psychometrically sound instrument was developed. Responsiveness testing must be conducted to determine whether the questionnaire will be useful in reliably obtaining quantifiable assessments from owners regarding the severity and impact of chronic pain and its treatment on dogs with osteoarthritis.