Biomedical subjects

M D Olver

Publications and source records attributed to M D Olver.

8 recordsLinked to original sources

PubMed1998

Effects of sweet, bitter and soaked micronised bitter lupins on duckling performance.

1. The feeding value of sweet white lupins (Lupinus albus variety Hanli), bitter lupins (Lupinus angustifolius) and soaked micronised bitter lupins on male Pekin duckling performance was examined. 2. Four isocaloric and isonitrogenous diets were formulated with 1 containing no lupin and the other 3 containing 400 g/kg sweet, bitter or soaked micronised bitter lupins. The 3 lupin diets were then blended appropriately to produce 16 experimental diets containing 0, 50, 100, 200, 300 and 400 g/kg sweet, bitter and soaked micronised bitter lupins, and fed to Cherry Valley Super M Pekin ducklings for 6 weeks. 3. The feeding of bitter lupins to ducklings at 200, 300 and 400 g/kg diet resulted in a poorer performance (P < 0.01) with regard to body weight gain, food intake and food conversion ratio than feeding the control diet. Carcase moisture was higher and carcase fat content lower (P < 0.01) at the 400 g/kg concentration only. No significant differences were observed with carcase protein or carcase ash content. No significant differences were observed between treatments and the control when different amounts of sweet or soaked micronised bitter lupins were fed. 4. There were significant linear adverse responses (P < 0.01) with bitter lupins in most of the variables studied whereas no responses were observed with sweet or soaked micronised bitter lupins as the concentration of lupins in the diet increased. The soaked micronised bitter lupins performed as well as the sweet lupins, showing that the amount of bitter lupins used in duckling diets can be increased to 400 g/kg after this treatment.

Animal Nutritional Physiological Phenomena↗

PubMed1997

Effect of sweet lupins on duckling growth.

1. The feeding value of sweet White Lupin (Lupinus albus variety Buttercup) for Pekin (Cherry Valley) ducklings was evaluated in isocaloric and isonitrogenous diets formulated to contain 0, 100, 200, 300 and 400 g/kg lupins. Male and female ducklings were housed together and fed on starter diets from 0 to 3 weeks and finisher diets from 4 to 7 weeks. 2. Inclusion of sweet lupins at 400 g/kg diet (containing less than 0.1 g/kg alkaloids) had no deleterious effects (P < 0.05) on live weight, efficiency of food utilisation, dressed carcase weight and carcase fat content.

Adipose Tissue↗

PubMed1997

Effect of sweet, bitter and soaked micronised bitter lupins on broiler performance.

1. The feeding value for broilers of sweet white lupins (Lupinus albus variety Hanti), bitter lupins (Lupinus angustifolius) and soaked micronised bitter lupins was examined. 2. Four isocaloric and isonitrogenous diets were formulated; one contained no lupins and the other 3 contained 400 g/kg sweet, bitter or soaked micronised bitter lupins. The 3 lupin diets were blended appropriately to produce 16 experimental diets containing 0, 50, 100, 200, 300 and 400 g/kg sweet, bitter and soaked micronised bitter lupins, respectively, and these were fed to Ross broilers for 6 weeks. 3. The feeding of diets containing bitter lupins to broilers at 300 and 400 g/kg and soaked micronised bitter lupins at 400 g/kg resulted in significantly different body weights, food intakes, food conversion ratios, carcase moisture and carcase fat contents from those of birds fed on the control diet. No significant differences were observed with carcase protein or carcase ash contents. 4. There were significant linear adverse responses with bitter and soaked micronised bitter lupins in most of the parameters studied whereas no responses were observed with sweet lupins as the dietary inclusion rate of the lupins increased. The soaked micronised bitter lupins performed better than the bitter lupins showing that the amount of bitter lupins in broiler diets can be increased by this method.

Aging↗

PubMed1997

Effect of feeding clinoptilolite (zeolite) on the performance of three strains of laying hens.

1. One hundred and twenty 16-week-old single combed pullets of three strains were fed on a diet containing 135 g protein/kg with or without 50 g clinoptilolite/kg in a trial with 20 hens per treatment. Sterile river sand replaced clinoptilotile in the control diet in order to keep the diets isoenergetic. The hens were individually caged in a naturally ventilated laying house and fed one of the two diets for ten 28-d periods. 2. Significant dietary effects of feeding clinoptilolite were observed with number of eggs laid per hen, shell thickness, efficiency of food utilisation and droppings moisture content. No significant dietary effects between treatments were observed with body weight, age at first egg, egg weight. Haugh units, food intake/hen and rate of amino acid absorption of radioactive lysine and methionine into the bloodstream. Significant differences between strains were observed with regard to all parameters except food intake/hen. There were no significant strain X clinoptilolite interactions.

Animals↗

PubMed1997

Effect of choice feeding on the performance of broilers.

1. Male broilers from, 21 to 56 d of age were fed their diet either mixed as pellets or mash, or as separate ingredients presented on a free-choice basis, to determine whether feeding method affected growth, carcase composition or profitability to 56 d of age. 2. The 12 treatments were: 2 completely balanced diets fed as mash or pellets, 8 choice fed diets containing maize or sorghum as the energy source (whole or mash) and protein concentrate (pellets or mash) and 2 unbalanced mixed mash diets containing 50% grain (maize or sorghum) plus 50% protein concentrate. 3. For the choice treatments, one food, grain (maize or sorghum) or protein concentrate (mash or pellets), was placed in each feeder. Broilers fed the complete pelleted or mash diet received the diet in both feeders. Food consumption was recorded weekly. Broilers were weighed at 42 and 56 d of age. 4. There were no significant differences between treatments and the pelleted control diet with regard to body weight, food consumed, food efficiency, carcase, ash, dressing percentage and mortality. 5. Choice fed broilers receiving the energy source as whole grains had larger gizzards while the higher protein diets (50/50) resulted in a higher carcase moisture and protein but lower carcase fat than the broilers fed the pelleted control diet. 6. The main advantage of choice feeding appears to be the economical savings of feeding whole grains as the energy source.

Analysis of Variance↗

PubMed1995

Effect of restricted feeding during the rearing period and a "forced moult" at 40 weeks of production on the productivity of Pekin breeder ducks.

1. Six males and 24 female Cherry Valley Pekin ducklings were randomly allocated to each of 12 pens to test the effects of quantitative food restriction during the rearing period on the subsequent reproductive performance. At the end of the laying period (60 weeks) a "forced moult" was introduced and its effect on a further 40 weeks production investigated. 2. The 3 rearing treatments were 50% of ad libitum intake from 3 to 20 weeks; 75% of ad libitum intake from 3 to 20 weeks and ad libitum intake throughout. During the laying period (20-60 weeks) and post forced-moult period (60-100 weeks) duck breeder pellets were fed ad libitum to all groups. 3. Highly significant (P < or = 0.01) differences in favour of the restricted groups over the ad libitum-fed groups were observed in most of the responses studied. The following were the main advantages of food restriction: lower lifetime food intake, lower carcase fat content at 20 weeks, delay in sexual maturity, higher egg production, higher peak and terminal production, higher fertility, higher hatchability of eggs set and lower mortality. Egg mass and hatchability of fertile eggs was not influenced by food restriction in this experiment. The use of a "forced moult" showed that it could be of economical importance. 4. Difference between treatments in respect of absolute and relative visceral masses were also investigated. The absolute masses of the intestine, heart, gizzard and liver all decreased as the degree of food restriction increased. The relative visceral masses showed the opposite trend with the exception of the heart which showed no significant differences between treatments.

Aging↗

PubMed1989

Effect of feeding clinoptilolite (zeolite) to three strains of laying hens.

1. One hundred and twenty 16-week-old, single combed pullets of three strains were fed on a diet containing 160 g protein/kg with or without 50 g clinoptilolite/kg in a trial with 20 hens per treatment. Sterile river sand replaced clinoptilolite in the control diet in order to keep the diets isonergetic. 2. The hens were individually caged in a naturally-ventilated laying house and fed on one of the two diets for ten 28-d periods. 3. No significant dietary effects between treatments were observed with respect to body weight, age at first egg, egg weight, Haugh scores or food intake/hen. 4. Significant dietary effects in favour of clinoptilolite feeding were noticed with the number of eggs laid per hen, shell thickness, efficiency of food utilisation, droppings moisture content and mortality. 5. Significant differences between strains were observed with respect to all measurements taken except food intake/hen d.

Aluminum Silicates↗

PubMed1989

Sodium bentonite as a component in layer diets.

1. Two hundred and forty Amber-link pullets were individually caged in a naturally-ventilated laying house and fed one of four isoenergetic, isonitrogenous diets containing 0, 20, 40 or 80 sodium bentonite/kg for 44 weeks. 2. No significant dietary effects were observed between treatments with regard to body weight at 20 or 64 weeks, age at first egg, egg weight, Haugh score or egg shell thickness. 3. Significant positive linear responses were observed with live weight at first egg (P less than 0.01), food consumed/hen d (P less than 0.05) and faecal moisture percentage (P less than 0.01). Significant negative linear (P less than 0.01) responses were observed with bacterial counts in the proximal and distal ends of the intestine. 4. A significant negative quadratic (P less than 0.05) response was noticed with egg production per hen. 5. A significant negative cubic (P less than 0.01) response was found with food conversion ratio (g food/g eggs).

Animal Feed↗