Soil and agronomic factors associated with cadmium accumulations in kidneys of grazing sheep

SUMMARY Mean concentration of cadmium (Cd) in kidneys of hogget sheep from 67 flocks grazing in the Agricultural Region of Western Australia was tested for association with soil, pastoral, climatic and nutritional factors. Hoggets grazing pastures on acidic soils and soils with a sandy-textured surface had higher Cd concentrations in kidneys than hoggets grazing pastures on more alkaline soils or soils with a clay-textured surface. Application of more than 100 kg of phosphatic fertiliser during the past 3 years to loamy soils was also associated with greater Cd concentration in kidneys of the grazing animals.     

Mild infectious laryngotracheitis in broilers in the southeast

During 2001, a mild infectious laryngotracheitis virus (ILTV) infection occurred in broiler flocks in the southeastern United States. Clinical signs included mild tracheitis, swollen sinuses, and conjunctivitis, with no increased mortality and minimal serologic response. Infrequent intranuclear inclusion bodies with or without syncytial cell formation were observed in eyelid, trachea, and larynx and in the chorioallantoic membrane of infected embryos. Immunohistochemistry and a nested infectious laryngotracheitis polymerase chain reaction (ILT PCR) were utilized to confirm the presence of ILTV nucleic acid in fixed tissues. In addition, 2-wk-old specific-pathogen-free (SPF) birds inoculated with field material exhibited the mild signs observed in broilers in the field. Tracheal swabs and tissues taken from these SPF birds were also positive by nested ILT PCR. Restriction fragment length polymorphism analysis of ILT PCR products indicated that ILT virus associated with mild respiratory disease in the southeast is related to the chicken embryo origin vaccine type strains.     

Comparative efficacy of enrofloxacin, oxytetracycline, and sulfadimethoxine for the control of morbidity and mortality caused by Escherichia coli in broiler chickens

The purpose of the present study was to compare the ability of enrofloxacin, oxytetracycline, and sulfadimethoxine to reduce morbidity and mortality caused by Escherichia coli (colibacillosis) in broiler chickens. The chickens were raised in 80 pens (20 birds per pen) with 20 pens representing each treatment group under simulated commercial conditions that produced a colibacillosis challenge scenario. Each group of 20 randomized pens (replicates) was given one of four water treatments. Chickens that received enrofloxacin had significantly less mortality (P < 0.01), lower average gross pathology (colibacillosis) scores (P < 0.01), and better feed-conversion ratios (P < 0.05) than did chickens that received either oxytetracycline or no medication. Chickens that received enrofloxacin had significantly less mortality and lower pathology scores than those that received sulfadimethoxine and numerically lower feed conversion than the sulfadimethoxine group. Results from the present study show that enrofloxacin is superior to oxytetracycline and sulfadimethoxine for the control of morbidity and mortality caused by E. coli in broiler chickens. Our findings will help veterinarians choose and prescribe the most efficacious antimicrobial when treating colibacillosis.     

The Use of Colonic Irrigation to Control Fecal Incontinence in Dogs With Colostomies

OBJECTIVE: To determine if once-daily colonic irrigation results in fecal continence for a 24-hour period in dogs with colostomies and if colonic volume increased in response to the irrigation. STUDY DESIGN: A prospective controlled experimental study. ANIMALS: Four intact male and one intact female mixed breed dogs. MATERIALS: All dogs received left end-on paralumbar colostomies. Four dogs received once-daily colonic irrigation for 8 weeks, whereas the control dog did not. Daily fecal weights were recorded for the length of the study in all dogs. Barium enema studies and volumetric studies were used to determine colonic volumes. RESULTS: Daily fecal weights were significantly decreased in treatment dogs compared with the control dog. Colonic volume increased in irrigated dogs in response to daily irrigation over the 8 week period of the study. CONCLUSIONS: Colonic irrigation resulted in significantly decreased fecal production over a 24-hour period. Therefore management of dogs with colostomies would be more practical and cost effective. It did not result in complete fecal continence in this study. Further clinical studies are indicated to determine if longer periods of irrigation would result in complete continence.     

The dietary regime of detritivorous fish from the River Jacaré Pepira, Brazil

The diet of detritivorous fish was analysed at four distinct habitats in a tropical river during the wet and dry seasons. Two methodologies were used to determine the diet of the fish: (1) the direct analysis of the stomach contents; and (2) the use of stable carbon isotopes. Both methods indicated food partitioning among the fish. The stomach contents showed what the fish had ingested when captured and the ¹³C isotope indicated what it had assimilated over a long period of time. The ¹³C isotope suggested the existence of sectional differences in the feeding of the detritivorous fish along the river. Plants employing the C₄ photosynthesis pathways seem to have little influence on the diet of these fish. This method proved to be more appropriate for the detection of the main food sources of the captured fish.     

Artificial reef placement: a red snapper,Lutjanus campechanus,ecosystem and fuzzy rule‐based model

Abstract This study on reef placement involves two aspects: (1) the development of a bioenergetics model for red snapper, Lutjanus campechanus (Poey), in Gulf of Mexico waters off the coast of Alabama, where significant numbers of artificial reefs are thought to exist, and (2) a fuzzy rough set model by which parameters determined from the bioenergetics model can provide a decision tool for optimally spacing artificial reefs during deployment. The bioenergetics and consumption rates of L. campechanus by age class foraging on artificial reefs in the Gulf of Mexico off the coast of Alabama provided input into the fuzzy rule‐based model. After conducting multiple simulations, highest certainty in optimal reef spacing was achieved for reef distances between 0.50 and 0.95 km such that no more than two fit within a 1‐km² area. Results can inform fisheries managers about placement of artificial reefs to affect the health and survival of reef‐associated species.     

Effect of practical diets with different protein levels on the performance of Farfantepenaeus paulensis juveniles nursed in a zero exchange suspended microbial flocs intensive system

Farfantepenaeus paulensis juveniles (72 ± 24 mg), were reared in a suspended microbial flocs system and fed practical diets containing increasing amounts of crude protein (250, 300, 350, 400 and 450 g kg^?1 CP). Development of microbial flocs was promoted by high aeration rates and fertilization with wheat bran and molasses. Flocs were composed of detritus in the form of flocculated matter colonized by heterotrophic bacteria, cocoid and filamentous cyanobacteria, flagellate and ciliate protozoa and rotifers. Proximate composition analysis of the suspended microbial floc showed CP levels of 304 g kg^?1. After 45 days, mean shrimp survival were above 89%, with no significant differences between treatments. Shrimp fed diets with 350 g kg^?1 or higher CP content achieved significant higher (P < 0.05) final weight (0.66–0.68 g), weight gain (0.58–0.61 g) and instantaneous growth rate (0.049–0.050), with feed conversion rates (2.17–2.30) significantly lower (P < 0.05). Results show that, when rearing is carried out in a suspended microbial flocs system, dietary CP levels can be kept at 350 g kg^?1. Furthermore, results confirm that microbial‐based systems allow shrimp culture without compromising the surrounding environment and shows the possible reduction of production costs and fish meal dependence.     

Transduction and Transplantation of Spermatogonia into the Testis of Ram Lambs through the Extra-testicular Rete

Spermatogonial transplantation will provide a new way to study spermatogenesis in domestic animals, disseminate male genetics and produce transgenic animals, if efficiency can be improved. We evaluated a 'surgical' method for transplanting donor cells into testes of ram lambs, where the head of the epididymis is reflected, and a catheter introduced into the extra-testicular rete testis. We also tested transduction of ram spermatogonia with a lentiviral (LV) vector as a means to identify permanent colonization, and introduce genes into donor cells. Eight ram lambs, 11- to 13-week olds, were the recipients: in five, spermatogonia were injected into one testis, and the contralateral testis was an un-manipulated control: in two, spermatogonia were injected into one testis and the contralateral was sham-injected: in one, both testes were injected. Six lambs received spermatogonia labelled with a cell-tracking dye and these were collected 1 or 2 weeks after transplantation; three lambs received spermatogonia transduced with a LV vector driving the expression of enhanced Green Fluorescence Protein and these were collected after 2 months. Donor cells were detected by immunohistochemistry in tubules of seven of nine recipient testes. Approximately 22% of tubule cross-sections contained donor cells immediately after transplantation, and 0.2% contained virally transduced cells 2 months after transplantation. The onset of spermatogenesis was delayed, and there were lesions in both injected and sham-injected testes. Despite the effects of the surgery, elongated spermatids were present in one recipient testis 2 months after surgery. The results suggest that, after modifying the surgical and transduction techniques, this approach will be a means to produce good colonization by donor spermatogonia in sheep testes.