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Efficiency of feeding Duddingtonia flagrans chlamydospores to control nematode parasites of first-season grazing goats in France.

A field trial, conducted over two consecutive years, was aimed at assessing the efficacy of the administration of spores of the nematophagous fungus Duddingtonia flagrans to young goats for the control of nematode parasite infections on a French commercial dairy goat flock. For both years, the first-year grazing kids were divided into two similarly managed groups (fungus and control groups): in 2003 a daily dose rate of 5 x 10(5) spores/kg body weight was given to the fungus-group animals, while in 2004 a daily dose rate of 10(6) spores/kg body weight was used; the other half of the kids, acting as control, did not receive the spores. Parameters measured every 3 weeks included nematode egg excretion, larval development in faecal cultures and pasture larval counts. Additionally, at the beginning, the middle and the end of each grazing season, the goats were weighed and blood samples for pepsinogen determination were collected. In 2003, similar results were recorded for all the measured parameters in the control and fungus groups. In contrast, in 2004, the kids receiving the spores showed lower faecal egg counts and pepsinogen levels at the end of the season and higher growth rate compared to kids of the control group.

Animals↗

Feeding method and health outcomes of children with cerebral palsy.

Disorders of feeding and swallowing are common in children with cerebral palsy. Feeding and swallowing disorders have significant implications for development, growth and nutrition, respiratory health, gastrointestinal function, parent-child interaction, and overall family life. Assessments need to be comprehensive in scope and centered around the medical home. Oral feeding interventions for children with cerebral palsy may be effective in promoting oral motor function, but have not been shown to be effective in promoting feeding efficiency or weight gain. Feeding gastrostomy tubes are a reasonable alternative for children with severe feeding and swallowing problems who have had poor weight gain.

Cerebral Palsy↗

Efficiency of feeding Duddingtonia flagrans chlamydospores to grazing ewes on reducing availability of parasitic nematode larvae on pasture.

Gastrointestinal nematodes are of concern in sheep production because of production and economic losses. Control of these nematodes is primarily based on the use of anthelmintic treatment and pasture management. The almost exclusive use of anthelmintic treatment has resulted in development of anthelmintic resistance which has led to the need for other parasite control options to be explored. The blood sucking abomasal parasitic nematode Haemonchus contortus causes severe losses in small ruminant production in the warm, humid sub-tropic and tropics. This study evaluated the effectiveness of a nematode trapping fungus, Duddingtonia flagrans, in reducing availability of parasitic nematode larvae, specifically H. contortus, on pasture. Chlamydospores of D. flagrans were mixed with a supplement feed which was fed daily to a group of crossbred ewes for the duration of the summer grazing season. A control group was fed the same supplement feed without chlamydospores. A reduction in infective larval numbers was observed in fecal cultures of the fungus-fed group. Herbage samples from the pasture grazed by the fungus-fed group also showed a reduction in infective larvae. There were no significant (P > 0.05) differences in overall fecal egg count, packed cell volume or animal weight between fungus-fed and control groups. Tracer animals were placed on the study pastures at the end of the study to assess pasture infectivity. Although tracer animals were only two per group, those that grazed with the fungus-fed group had substantially reduced (96.8%) nematode burdens as compared to those from the control group pasture. Results demonstrated that the fungus did have activity against nematode larvae in the feces which reduced pasture infectivity and subsequently nematode burdens in tracer animals. This study showed that D. flagrans, fed daily to grazing ewes, was an effective biological control agent in reducing a predominantly H. contortus larval population on pasture.

Animal Feed↗

Alleles of cytosolic phosphoenolpyruvate carboxykinase (PEPCK): trait association and interaction with mitochondrial PEPCK in a strain of White Leghorn chickens.

White Leghorn chickens from a nonselected closed population were typed for two RFLP located in the 3' end of the gene coding for cytosolic phosphoenol-pyruvate carboxykinase (PEPCK-C), a major control gene of gluconeogenesis. The two RFLP gave rise to three alleles (or haplotype classes), thus defining six genotypes. Feed efficiency (FE) and residual feed consumption (RFC) varied significantly among the genotypes and indicated that all three haplotypes differed from each other. FE is the ratio between feed consumption and egg mass produced, whereas RFC is the feed consumption after correcting for BW and egg production. There was significant interaction between PEPCK-C genotypes and mitochondrial PEPCK (PEPCK-M) genotypes defined by a single RFLP. The latter enzyme catalyzes the same reaction but is located in the matrix of the mitochondria and is encoded by a different nuclear gene. Interaction was evident from an analysis of the egg weight and egg specific gravity in the early phase of egg laying. It was such that the effect of the variation in one gene depended entirely on the genotype of the second gene. In addition, significant genotypic disequilibria were observed between two of the three alleles of PEPCK-C and between one of these alleles and the two RFLP alleles of PEPCK-M. This finding indicates variations of genes in the gluconeogenesis pathway may affect feed utilization and egg production traits, as well as reproductive fitness.

Alleles↗

Influence of breast feeding, and adapted and hydrolyzed formulas on biliary bile acids in newborn guinea pigs.

BACKGROUND: The type of feeding can differently influence bile acid ontogeny during the period of physiologic cholestasis that characterizes early human development. AIM: To investigate the effects of feeding from birth, conventional or partially protein hydrolyzed cow's milk formulas were compared with breast milk regarding bile acid concentration and the composition of gallbladder bile in newborn guinea pigs. METHODS: Forty newborn guinea pigs were allocated to one of three different feeding regimens: breast milk (n = 14), intact protein formula (n = 13) and partially protein hydrolyzed formula (n = 13). After 8 days, one third of the pups from each group was sacrificed; another third was sacrificed on the 14th day and the remainder on the 20th day of life. Bile acids in gallbladder bile were analyzed by gas chromatography/mass spectrometry and HPLC. RESULTS: During the first 2 weeks of life, weight gain was significantly higher in breast-fed than in artificially fed pups. An age-related increase in total biliary bile acid concentrations was evident for breast-fed and hydrolyzed formula-fed animals, but not for those fed intact protein formula. Breast-fed animals had the highest total biliary bile acid concentrations on day 20 of life, with significant increases in chenodeoxycholic and 7-oxo-lithocholic acid concentrations, which were absent in the other two groups. Concentrations of 7-oxo-lithocholic acid on day 8 were significantly higher in animals fed intact protein formula compared with breast-fed and partially protein hydrolyzed formula-fed animals. CONCLUSIONS: In newborn guinea pigs, breast feeding is associated with a marked increase in biliary bile acid concentrations, which was not observed in artificially fed animals. The higher biliary bile acid concentrations and better weight gain in our breast-fed animals may reflect a greater feed efficiency associated with natural feeding. Biliary bile acid composition on day 8 suggests more rapid intestinal bacterial bile acid biotransformation in animals fed intact protein formula compared to other feeding regimens.

Animals↗

Evaluation of recombinant porcine somatotropin on growth performance, carcass characteristics, meat quality, and muscle biochemical properties of Belgian Landrace pigs.

The dose related effects of recombinant porcine somatotropin (rpST) on growth, carcass characteristics, muscle properties, and meat quality were investigated in lean Belgian Landrace finishing pigs. Ninety-six pigs (48 barrows and 48 gilts) were injected daily with either vehicle, 1.5, 3, or 6 mg of rpST from 60 to 97.5 kg live weight. Each treatment group consisted of six pens of four pigs each (two of each sex). Pigs were given ad libitum access to a high-protein (20.4% CP) cereal-based diet. Administration of rpST increased (P less than .05) growth rate (16.3 to 25.4%) and improved (P less than .05) feed efficiency (16.9 to 29.4%). Feed consumption was reduced (12%; P less than .05) only in the 6 mg of rpST group. Liver, kidney, and heart weights were increased (P less than .05) in the 3 and 6 mg of rpST groups. Although the Belgian Landrace pigs are bred for superior carcass quality, rpST further improved (P less than .05) carcass composition at all dose levels as evidenced by a reduction (10 to 50%) in a number of subcutaneous fat depth measurements, an increase (10 to 20%) in longissimus muscle area, and an improvement in the lean cut:fat cut ratio. Rate of pH decline in the gluteus and longissimus muscles was similar, but rapid, in all groups (pH after 30 min = 5.74 to 5.94); the ultimate (24 or 72 h) pH was .15 to .2 pH units higher (P less than .05) in the pigs that received the 3 and 6 mg of rpST doses.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

Effects of placing cattle on feed at two-month intervals and housing on feedlot performance and carcass grades.

A 5-yr study was conducted involving the placement of yearling steers on feed at 2-mo intervals under three different housing systems. A total of 3,571 steers (180 pens) initially averaging 318 kg was used. Evaluations were made for DM intake, ADG, feed efficiency (FE), carcass quality (QG), and yield grades (YG). Cattle were assigned to either an open lot with overhead shelter (S), an open lot without overhead shelter (NS), or an open-front confinement building (C). Each treatment consisted of two lots of 20 steers each per interval per trial. Corn grain provided 85% of the energy; the remainder was supplied by corn silage and protein supplement. Cattle were fed 140 to 180 d to achieve an average slaughter weight of 500 kg. The main effects of year (Y), month (M), and housing (H) affected DM intake, ADG, FE, and final live weight (P less than .01). The interactions for Y x M, M x H and Y x M x H affected ADG (P less than .05). Month and H affected hot carcass weight (P less than .01). Year affected YG, and year and month affected QG (P less than .01). Month effects on DM intake and ADG indicated that cattle started in May had the highest intake and ADG (P less than .05) and that cattle started in November had the lowest (P less than .05) DMI and ADG. Month effects on FE indicated that cattle were most efficient when placed on feed during March, May, and July (5.82, 5.72, and 5.66 kg DM/kg gain; P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

Performance of male pigs immunized against GnRH is related to the time of onset of biological response.

In this study, the performance of male pigs immunized against GnRH was determined in relation to the onset of their biological response to the immunization. Pigs were immunized at 9 and 17 wk of age and were housed in a pen together with both a surgically castrated and an intact boar littermate. Feed intake was restricted to 2.8 to 3.2 times maintenance requirement for energy. Animals were weighed weekly and slaughtered at 108 kg BW. Depending on the time of onset of the response after immunization in terms of biological effects, immunized pigs were retrospectively grouped into two categories. One category consisted of the immunized pigs, which had undetectable or low levels of LH and testosterone at the time of booster immunization-known as "early" responding immunocastrates (E-IM, n = 8), whereas the "late" responding immunocastrates (L-IM, n = 7) had substantial LH and testosterone levels at that time. This dichotomy of the response to immunization also was reflected in testis weight, with 17 g and 40 g for E-IM and L-IM pigs, respectively. At slaughter, testis size and weight were reduced (P < 0.001) in the immunocastrated pigs as compared to the intact boars. Androstenone concentrations in backfat of all immunocastrated pigs were undetectable. Growth performance (i.e., ADG and feed efficiency [FE, g gain/kg feed]), was better in boars and L-IM pigs than in surgical castrates and E-IM pigs (P < 0.05). Average daily gain and FE did not differ between E-IM pigs and the surgical castrates, but intact boars performed better than L-IM (P < 0.02). There were no significant differences in carcass quality (backfat thickness and meat percentage) between boars and surgical castrates at slaughter. However, for both characteristics L-IM pigs and intact boars performed better (P < 0.03) than E-IM pigs. Thus, growth performance in L-IM is better than in either E-IM or surgical castrates.

Androstenes↗

Sunflower meal as a component of fat-supplemented diets for broiler chickens.

An experiment was conducted to determine the influence of diets containing sunflower meal (SFM; 32.6% protein and 18.4% crude fiber) with and without supplemental animal-vegetable (A-V) fat on performance of broiler chickens. A complete factorial arrangement of three levels of SFM (0, 10, or 20%) and two levels of A-V fat (0 or 6%) was used. Diets were fed for ad libitum access to broilers from 1 day to 7 wk of age. Body weight, feed consumption, and MEn of the diets were determined at 4 and 7 wk of age. Results show that the inclusion of 10 or 20% SFM had no effect on body weight gain but impaired (P less than .01) feed efficiency (FE; kilograms of feed consumed per kilogram of gain). The use of 6% A-V fat in the diet increased (P less than .01) weight gain and improved (P less than .01) FE at all levels of SFM in the diet. The extent of improvement in FE caused by 6% A-V fat was greatest with the 10% SFM diet. Nitrogen-corrected metabolizable energy decreased with each 10% increment of SFM and increased with the inclusion of 6% A-V fat in the diet; no interactions were observed.

Animal Feed↗

Effects of environment on growth, efficiency of feed utilization, carcass fatness, and their association.

The effects of environmental factors (house type, temperature, and type of watering system) on gain (G), feed consumption (FC), feed conversion (FCR), accumulation of abdominal fat (AF), and the association between FCR and AF of broilers were studied in a series of seven experiments. In addition, the adjustment of broilers to new housing environments and the factors affecting this adjustment were evaluated. The 4- to 7-wk G and FC were greater in groups raised at 21.1 C than 26.7 C. There were no consistent effects of environmental temperature on FCR (significantly reduced in 21.1 C groups compared with the 26.7 C groups in two of four trials) or in AF (significantly greater in 21.1 C groups than in 26.7 C groups in one of four trials). Environmental temperatures had no consistent effect on the relationship between FCR and AF. Both waterer types and environmental temperature affected the adjustment of broilers to placement in individual cages. Adjustment was better (less mortality and shorter periods of reduced FC) in the 21.1 C environment and when cup instead of trough waterers were provided. The 4- to 6-wk G and FC were reduced in the caged birds compared with the floor pen birds, but the FCR and AF were not consistently different. The initial (4-wk) BW significantly affected the 6-wk BW, G, FC, and FCR, but was not correlated with AF.

Adaptation, Physiological↗

Enhanced efficiency of feeding and mixing due to chaotic flow patterns around choanoflagellates.

The motion of particles and feeding currents created by micro-organisms due to a flagellum are considered. The calculations are pertinent to a range of sessile organisms, but we concentrate on a particular organism, namely Salpingoeca amphoridium (SA) (a choanoflagellate), due to the availability of experimental data (Pettitt, 2000). These flow fields are characterized as having very small Reynolds numbers, which implies that viscous forces dominate over inertial ones consistent with using the Stokes flow equations. The flow generated by the flagellum is modelled via the consideration of a point force known as a stokeslet. The interaction between the boundary, to which the organism is attached, and its flagellum leads to toroidal eddies, which serve to transport particles towards the micro-organism, promoting filtering of nutrients by the microvilli which constitute the cell's collar (the filtering mechanism in SA). It is our conjecture that the interaction of multiple toroidal eddies will lead to chaotic advection and hence enhance the domain of feeding for these organisms. The degree of mixing in the region around SA is investigated using chaotic and statistical measures to study the influence the flagellum has on the surrounding fluid. The three-dimensional particle paths around such organisms are also considered with the aim of showing that the plane within which they are situated is an attractor.

Animals↗