Improving high soy feed formulations for the Florida pompano Trachinotus carolinus through newer soy products and carbohydrase supplementation

Florida pompano perform well on soy‐based, low‐animal protein diets. These diets may be improved through the use of enzymes as a feed supplement or as pretreatment of the soy product prior to inclusion. Novel soy products produced through enzyme treatment or fermentation often have higher protein content and lower levels of indigestible carbohydrates. Two trials were conducted to evaluate the potential of enzyme supplements. The first trial evaluated the effects of carbohydrase supplementation to diets based on two different soybean meals (commodity or selectively bred meal). Pompano fed the selected soybean had significantly improved growth rates and feed efficiency, while enzymatic supplementation had no significant effect on fish performance. However, enzyme supplementation increased phosphorus and energy retention when added to diets based on commodity soybean meal. Carbohydrase supplementation improved dry matter digestibility in commodity soy‐based diets but had no significant effect on selected soybean‐based diets. The second growth trial consisted of an increasing inclusion of an enzymatically treated soybean meal product (NutriVance). Results indicate that NutriVance can replace the totality of commodity soybean without impacting fish performance. Digestibility of the commodity soy, NutriVance, and a fermented soybean meal (Pepsoygen) was also evaluated, with no detectable difference in digestibility values.     

Comparison of culling rates among dairy cows grouped on the basis of serologic status for bovine leukemia virus

OBJECTIVE: To determine the association between serologic status for bovine leukemia virus (BLV) and culling rates by use of survival times in a commercial Holstein dairy herd. DESIGN: Longitudinal study. ANIMALS: 593 milking cows. PROCEDURE: Cattle were tested for antibodies against BLV by use of agar gel immunodiffusion or ELISA 4 times each year from 1989 to 1993 and then annually through 1999. Dates of birth, first calving, and culling or death were obtained from Dairy Herd Improvement Association records. Most cows were enrolled in the study on the date of first calving. Survival times were compared among seropositive, seronegative, and seroconverted cows with the Kaplan-Meier method and a Cox regression model stratified on the basis of year of birth. RESULTS: Complete records were available for 593 of 685 (87%) cattle in the dairy herd during the study period. Median survival time for all cows was 31.7 months. Survival times, which correspond to cull rates, did not differ significantly between seropositive and seronegative cattle, whereas cattle that seroconverted during the study had a significantly longer survival time. Year of birth was positively and significantly associated with survival time. CONCLUSIONS AND CLINICAL RELEVANCE: BLV serologic status was not associated with cull rate as measured by survival time in this dairy herd. This finding is in contrast to results of studies that used survival analysis techniques; our results may influence management decisions concerning BLV.     

Epidemiologic investigation of seroprevalence of antibodies to Toxoplasma gondii in cats and rodents

OBJECTIVE: To provide an epidemiologic investigation of the seroprevalence of antibodies to Toxoplasma gondii in populations of cats and wild rodents in Rhode Island and to address the possible epidemiologic role of wild rodents in the spread of toxoplasmosis. ANIMALS: 200 cats and 756 small wild rodents. PROCEDURE: Serum samples were obtained from 84 cats in animal shelters and 116 cats in veterinary hospitals. Serum samples were also obtained from 756 small wild rodents from multiple sites in Rhode Island. Sera from rodents and cats were assayed for antibodies to Tgondii by use of the modified agglutination test RESULTS: Overall, 42% (84/200) of cats had serum antibodies to Tgondii. Seroprevalence was not significantly different between stray (50%; 42/84) versus client-owned (36%; 42/116) cats, between male (43%; 40/94) versus female (42%; 39/93) cats, or between indoor (26%; 7/27) versus outdoor (39%; 35/89) cats. Seroprevalence rate of trapped rodents was 0.8% (6/756). Six rodents captured in Washington County accounted for of the seropositive rodents. Four of 6 of the seropositive rodents were trapped at a single site in Washington County (an abandoned barn). Five stray cats, known to have resided at the same site in Washington County as 4 of the seropositive rodents, were also found to be seropositive for antibodies to T gondii. CONCLUSIONS AND CLINICAL RELEVANCE: Seroprevalence rate in rodents was not correlated with the seroprevalence rate in cats. Stray cats, especially those known to be feral, may be more likely to perpetuate the cat-mouse cycle of T gondii than client-owned cats.     

Effects of I.M. injections on serum creatine phosphokinase (CPK) values in dogs

Intramuscular injections of compounds of low irritancy (bicillin, valium, saline) were found to cause significant elevations in serum CPK in dogs. This route of treatment must therefore be avoided in clinical conditions where CPK values have diagnostic or prognostic importance.     

Time-delayed influence of urban landscape change on the susceptibility of koalas to chlamydiosis

Context

Infectious diseases are important in the dynamics of many wildlife populations, but there is limited understanding of how landscape change influences susceptibility to disease.

Objectives

We aimed to quantify the time-delayed influence of spatial and temporal components of landscape change and climate variability on the prevalence of chlamydiosis in koala (Phascolarctos cinereus) populations in southeast Queensland, Australia.

Methods

We used data collected over 14 years (n = 9078 records) from a koala hospital along with time-lagged measures of landscape change and rainfall to conduct spatial and temporal analyses of the influence of landscape and environmental variables on prevalence of chlamydiosis and koala body condition.

Results

Areas with more suitable habitat were associated with higher levels of disease prevalence and better body condition, indicating that koalas were less likely to be impacted by chlamydiosis. More intact landscapes with higher proportions of total habitat are associated with a reduction in prevalence of chlamydiosis and a decrease in body condition. Increased annual rainfall contributed to a decrease in prevalence of chlamydiosis and an increase in body condition. Urbanization was associated with an increase in disease, however the effects of urban landscape change and climate variability on chlamydiosis may not manifest until several years later when overt disease impacts the population via effects upon body condition and reproductive success.

Conclusions

Our study highlights the importance of effects of landscape change and climate variability on disease prevalence in wildlife. This recognition is essential for long-term conservation planning, especially as disease often interacts with other threats.

     

Use of salmon by‐product meals as a replacement for anchovy meal in practical diets for the Pacific white shrimp (Litopenaeus vannamei)

A series of trials were conducted with Pacific white shrimp Litopenaeus vannamei, to evaluate the efficiency of two salmon meals as compared to anchovy meal. The basal diet contained 200 g/kg anchovy meal, which was systematically replaced (0%, 50%, 75% and 100%) with salmon meal on an isonitrogenous basis. Another two diets were formulated with a hydrolysed salmon meal to replace 50% and 100% anchovy meal. Each diet was randomly fed to four replicate groups of 25 and 30 shrimp per tank in clear (indoor) and green (outdoor) water trials, respectively. The results showed that growth performance and feed conversion ratio were not statistically different when salmon meal replaced anchovy meal in both trials. However, when hydrolysed salmon meal was used to replace 100% of the anchovy meal, growth performance of the shrimp significantly decreased. The four kinds of fish meal (anchovy, salmon by‐product meals and menhaden) were evaluated in an ingredient digestibility trial using the 70:30 replacement technique. In general, dry matter, energy, protein and individual amino acids digestibility of salmon meal were significantly higher than those of menhaden and anchovy meal. Results of this study demonstrated that salmon meals are a good protein sources which can replace anchovy meal.     

The Current State of Solar Modeling

Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations.     

The effects of between-row (alley widths) and within-row spacings ofGliricidia sepium on alley-cropped maize in Sierra Leone

The effects of spacings between hedgerows (alley widths) and the spacings of trees within hedgerows ofGliricidia sepium on growth and grain yield of maize were investigated at Senehun in southern Sierra Leone. Four between-row spacings (2, 4, 6 and 8 m) were combined with three within-row spacings (0.25, 0.50 and 1.00 m) in a split block design. Maize, at densities of 20,000, 40,000 and 53,333 plants ha^–1, was established in the alleys and also as pure crops. N, P and K fertilizers were applied to all plots before pruning of the trees began. When pruning started, only the pure maize plots received fertilizer; prunings from the hedgerows were returned to the appropriate alleys in the other plots.Plots with the highest maize populations consistently gave the best yields before pruning started, but lower populations gave improved yields after pruning. Yields of maize increased with increasing alley widths before the start of pruning, after which the narrower alleys of 2 and 4 m outyielded the wider ones by almost double, probably because of the large amount of nutrients applied in prunings. Lack of light limited grain yields before the start of pruning, when there was some shading by the hedgerows. Alleys of 2–4 m wide, planted no closer than 0.50 m within rows, resulted in more than twice the yields of maize than in the 8-m alleys planted at 0.25 m within rows, once the hedgerows were well established and were being managed.     

Immune response of pigs inoculated with virulent pseudorabies virus and pigs inoculated with attenuated or inactivated pseudorabies virus vaccine before and after challenge exposure

Pseudorabies virus (PRV) antibodies, detectable by indirect radioimmunoassay (IRIA), serum-virus neutralization test (NT), or microimmunodiffusion test (MIDT) were developed within 8 days after pigs were inoculated with virulent PRV or attenuated PRV vaccine. Indirect radioimmunoassay and NT titers in pigs inoculated with virulent PRV were developed at the same rate, with IRIA titers being higher than NT titers. Pigs inoculated with attenuated or inactivated PRV vaccine developed peak mean prechallenge NT antibody titers of 4 and 1 (reciprocals of serum dilutions), respectively. Pigs inoculated with attenuated PRV vaccine had peak mean prechallenge IRIA antibody titers of 6, whereas pigs inoculated with inactivated PRV vaccine had mean IRIA antibody titers of 64. Challenge exposure of swine inoculated with attenuated or inactivated PRV vaccine elicited quantitatively equivalent responses, as measured by IRIA or NT, which were higher than prechallenge titers. There were no false-positive IRIA, NT, or MIDT results obtained when sera from nonvaccinated, nonchallenge-exposed pigs were tested. It appears that the PRV infection status of a seropositive swine herd could be ascertained by serologically monitoring several representative animals from a herd, using the NT. If 2 or more tests of representative animals at 14-day intervals were done and the mean NT titer was 4 or less, it could be concluded that the herd was vaccinated against, but not infected with, virulent virus.