Quantitative amino acid analysis of feedstuff hydrolysates by reverse phase liquid chromatography and conventional ion-exchange chromatography

Corn, soybean meal, and isolated soybean protein samples were acid-hydrolyzed and analyzed for amino acid content by reverse phase liquid chromatography (LC) and by conventional ion-exchange chromatography (IEC) using an amino acid analyzer. The former method employed pre-column derivatization with orthophthalaldehyde (OPTA)/ethanethiol and fluorescence detection. In the LC procedure, glycine and threonine were not resolved, and proline and cyst(e)ine were not detected. In general, amino acid values obtained by LC and IEC compared closely within and across feedstuffs, and both agreed well with published amino acid composition data. The notable exceptions were aspartic acid, glutamic acid, and alanine. Results of this study suggest that reverse phase LC with pre-column OPTA derivatization can be applied to accurately measure primary amino acids in individual feedstuffs.     

Nutritional value of a highly digestible sorghum cultivar for meat-type chickens

The nutritional value of a newly discovered sorghum mutant cultivar (P851171), with high in vitro protein digestibility, was compared to those of corn and two normal sorghums (P721N and 611Y) in two chick feeding trials. Although 8-20 day protein efficiency ratios and net protein ratios of all three sorghums were inferior to those of corn, P851171 and 611Y had markedly greater mean true amino acid digestibilities (TAAD) than either corn or P721N. In a subsequent 42-day experiment, all three sorghums supported weight gains equal to those of the corn-fed chicks. Feeding suboptimal levels of dietary protein resulted in reduced weight gains and no observed benefits of P851171 or 611Y. Furthermore, chicks fed P851171 exhibited poorer feed/gain values as compared to those fed the other cereals. It is possible that the starch content/carbohydrate profile of P851171 was inferior to that of the other sorghums, which offset its superior TAAD and resulted in poorer broiler performance.     

Evaluation and delivery of domestic animal health services in remote communities in the Northwest Territories: A case study of status and needs

Domestic animal health services are supplied to communities in Canada's Northwest Territories (NT) in diverse ways, including private veterinary practices in 2 of 33 communities, and by mail-order, fly-in, free clinics, and a government-coordinated lay vaccinator program in some of the other 31 communities. We evaluated delivery, needs, and potential uptake of domestic animal health services in the Sahtu Settlement Area, NT by offering free clinics for 225 dogs in 2008 and 2009; and administered questionnaires to 42 dog owners and 67 students in 2008. Owners indicated that 20% of dogs were neutered, 37% had had rabies vaccinations, and 29% had been dewormed. Physical examination of dogs demonstrated that 54% were "thin" and 4% were "emaciated." Owners and youth showed a range of attitudes toward dogs and supported improved domestic animal health services. Future services need to build on existing programs and collaborate with communities to ensure relevance, ownership, and sustainability.     

Effect of beta, beta'-tetramethyl-substituted hexadecanedioic acid (MEDICA 16) on laying hen performance and egg yolk lipid composition.

1. beta, beta'-tetramethyl-substituted hexadecanedioic acid (MEDICA 16), an inhibitor of hepatic cholesterogenesis and lipogenesis in rats, was orally administered to 24-week-old White Leghorn hens for a period of 16 d. Hens were fed maize-soya-bean meal diets containing 0, 1.5, or 3.0 g MEDICA 16/kg. 2. Although MEDICA 16 did not affect egg weight, yolk weight, egg cholesterol content, or the efficiency of food utilisation, egg production was significantly reduced in birds fed 3.0 g MEDICA 16/kg compared to those fed the other two diets. 3. Total yolk monounsaturated fatty acids were significantly higher in eggs of hens fed both inclusion rates of MEDICA 16 compared to those of the control birds. In contrast, egg yolk total polyunsaturated fatty acid content and the ratio of polyunsaturated to saturated fatty acids were both inversely related to the dietary content of MEDICA 16. 4. These results suggest that MEDICA 16 primarily altered hepatic fatty acid metabolism, but not cholesterol synthesis, in laying hens.     

Relationship of high intensity step-up lighting to bone ash and growth plate closure of the tarso-metatarsus in turkeys

The reduced lameness observed in turkeys reared in a high intensity step-up (HISU) lighting programme as compared to a low intensity step-down (LISD) lighting regimen cannot be explained by differences in the inorganic matrix of the bone, because the proportions of bone ash, bone ash calcium, and bone ash phosphorus did not differ between lighting programmes. At 17 weeks of age, there was a significant difference in the proportion of closed growth plates in males reared on the HISU programme rather than on LISD lighting. These results support the hypothesis that HISU lighting reduces lameness by promoting earlier growth plate closure of long bones.     

Investigation, control and epizootiology of anthrax in a geographically isolated, free-roaming bison population in northern Canada.

In July 1993 anthrax caused significant mortality in an isolated, free-ranging population of bison (Bos bison athabascae) west of Great Slave Lake in the Northwest Territories. There was no previous record of anthrax in this area. An emergency response was undertaken to reduce the scale of environmental contamination and dissemination of anthrax spores and hence to reduce the likelihood of future outbreaks. One-hundred-and-seventy-two bison, 3 moose (Alces alces), and 3 black bear (Ursus americanus) carcasses were found. Visual detection of carcasses was enhanced with the use of an airborne, remote infrared sensing camera mounted externally on a helicopter. Fifty-five percent of the carcasses were located in forested or shrub-covered sites where detection would not have been likely without the thermal imaging equipment. Carcasses were disposed of by incineration and the sites were decontaminated with formaldehyde. Application of formaldehyde to carcasses prevented scavenging. The outbreak occurred after a prolonged period of drying between April and mid-July 1993 which followed several successive years of flooding of bison habitat. The "spore concentration hypothesis" provides the most conservative explanation for the occurrence of anthrax under the observed conditions.     

Assessment of egg nutrient compositional changes and residue in eggs,tissues, and excreta following oral administration of atorvastatin to laying hens

Laying hens were fed a control diet alone or with 0.06 g of atorvastatin, a synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, per 100 g of diet for 20 days. Compared to controls, egg yolks from treated hens contained greater amounts of amino acids and reduced levels of total fatty acids and cholesterol. In contrast, egg albumen amino acid contents were unaffected by dietary treatments. In a residue study, seven hens each received a single oral dose of approximately 20 microCi of [(14)C]atorvastatin. Approximately 71% of the radioactivity was recovered in the excreta and liver, whereas virtually no radioactivity was detected in kidney, heart, muscle, bile, plasma, or egg albumen at 15 days postdosing. Yolk radioactivity peaked at 4 days postdosing in six of the seven birds and was absent in eggs laid after day 10. Reminiscent of that of certain antibiotic drugs, the atorvastatin egg residue pattern appeared to coincide with the physiological pattern of daily yolk accretion within the ovary.     

Hydrolysate preparation for analysis of amino acids in sorghum grains: effect of oxidative pretreatment

Sorghum samples were either untreated or oxidized with performic acid (PA) before hydrolysis, and their amino acid contents were determined by cation exchange chromatography using an amino acid analyzer. HCl was used to destroy excess PA. Oxidative pretreatment of the samples resulted in increased yields of Cys (as cysteic acid), Met (as Met dioxide), and His, destroyed Tyr and Phe, and resulted in the appearance of an extraneous peak which most likely consisted of halogenation by-products (HBP) of Tyr and Phe. The destruction of Tyr and Phe occurred despite the presence of phenol, a halogen scavenger, in both the PA and hydrolysis reagents. The higher His values observed in all oxidized samples most likely resulted from the co-elution of His with Tyr and Phe HBP. It was concluded that the complete (except Trp) amino acid content of a feedstuff cannot be accurately determined from only one oxidized hydrolysate preparation by using this particular procedure.