|
|
Articles
by
Cesar Coto |
Total Records (
6 ) for
Cesar Coto |
|
 |
|
|
|
Cesar Coto
,
F. Yan
,
S. Cerrate
,
Z. Wang
,
P. Sacakli
,
P.W. Waldroup
,
J. T. Halley
,
C.J. Wiernusz
and
A. Martinez
|
|
A study was conducted to evaluate the effects of dietary levels of calcium, nonphytate
P (NPP), phytase and 25-hydroxycholecalciferol (25-OH) on live performance and
bone development in male chicks fed a wheat-based diet. Dietary treatments consisted
of a 2 x 2 x 4 x 4 factorial arrangements with two levels of supplemental phytase
(0 or 1200 FTU/kg), two levels of 25-OH (0 or 69 µg/kg), four levels of
calcium (0.20% less than a 2:1 ratio of Ca to NPP; 2:1 ratio of Ca to NPP; 0.20%
Ca greater than a 2:1 ratio of Ca to NPP; 0.40% Ca greater than a 2:1 ratio of
Ca to NPP) and four levels of NPP (0.35, 0.40, 0.45 and 0.50%) for a total of
64 treatments. The primary basal diet used to mix all experimental diets was supplemented
with a complete vitamin mix containing 5500 IU of cholecalciferol. Each diet was
fed to two pens of six male chicks of a commercial broiler strain in electrically
heated battery brooders for three consecutive trials using the same diet mix for
a total of six replicates per treatment. At 18 d birds were weighed, feed consumption
determined and all birds killed for bone measurements. Toes from all birds within
a pen were removed and ashed. Tibiae from both legs were removed and scored for
incidence and severity of tibial dyschondroplasia and for incidence of calcium
or phosphorus rickets. Ca: NPP ratios and calcium levels similar or higher than
NRC (1994) recommendations appear necessary for adequate bird performance. Phytase
supplementation improved performance parameters such as FCR and body weight, whereas
the addition of 25-OH to diets already containing 5500 IU/kg of cholecalciferol
had a negative effect on FCR due to a possible hypercalcemia condition. Bone development
was improved by increasing phosphorus and calcium levels. Moreover, supplementation
with 25-OH and its combination with phytase were effective in enhancing bone development.
Increasing Ca levels consistently reduced leg abnormalities. Addition of 25-OH
helped to relieve leg problems when suboptimal calcium levels were supplied while
phytase supplementation was effective for this purpose when high Ca levels were
given. The addition of these additives could be seen as an strategy to alleviate
problems with suboptimal Ca: NPP ratios. |
|
|
|
|
Cesar Coto
,
F. Yan
,
S. Cerrate
,
Z. Wang
,
P. Sacakli
,
J.T. Halley
,
C.J. Wiernusz
,
A. Martinez
and
P.W. Waldroup
|
|
A study was conducted to evaluate the effects of dietary levels of calcium (Ca), nonphytate P (NPP), phytase (Phy) and 25-hydroxycholecalciferol (25-OH) on live performance and bone development in male chicks fed a corn-based diet. Dietary treatments consisted of a 2×2×4×4 factorial arrangements with two levels of supplemental phytase (0 or 1200 FTU kg-1), two levels of 25-OH (0 or 69 µg kg-1), four levels of Ca (0.20% less than a 2:1 ratio of Ca to NPP; 2:1 ratio of Ca to NPP; 0.20% Ca greater than a 2:1 ratio of Ca to NPP; 0.40% Ca greater than a 2:1 ratio of Ca to NPP) and four levels of NPP (0.35, 0.40, 0.45 and 0.50%) for a total of 64 treatments. The primary basal diet was supplemented with a complete vitamin mix containing 5500 IU of cholecalciferol. Each diet was fed to six replicates per treatment; each pen having 6 birds. At 18 d birds were weighed, feed consumption determined and all birds killed for bone measurements. Toes from all birds within a pen were removed and ashed. Tibiae from both legs were removed and scored for incidence and severity of tibial dyschondroplasia and for incidence of Ca or P rickets. Ca: NPP ratios and Ca levels similar or higher than NRC (1994) recommendations appear necessary for adequate bird performance. Phy supplementation improved FCR, whereas the addition of 25-OH to diets already containing 5500 IU kg-1 of cholecalciferol had a negative effect on FCR due to a possible hypercalcemia condition. Bone development was improved by increasing NPP and Ca levels. Moreover, supplementation with 25-OH was effective in reducing leg abnormalities. Addition of 25-OH helped to relieve leg problems when suboptimal Ca levels were supplied while Phy supplementation was effective for this purpose when high Ca levels were given. These additives could be seen as a strategy to alleviate problems with suboptimal Ca: NPP ratios.
|
|
|
|
|
Zurong Wang
,
Sandro Cerrate
,
Cesar Coto
,
Fenglan Yan
and
P.W. Waldroup
|
|
This study was conducted to evaluate the bioavailability
of an organic copper source, MINTREX® Cu, compared with reagent
grade Cu sulfate as a source of Cu in broiler diets. Nutritionally
complete basal diets were supplemented with either copper sulfate or
MINTREX Cu to provide diets with 0, 10, 25, 50, 125, 250 and 500 mg
kg-1 of supplemental Cu. Fifty commercial broiler strain (Cobb
500) male chicks were placed in each of 48 pens. Each diet (except for 500
mg kg-1) was fed to four replicate pens. The 500 mg
kg-1 level was fed to two replicate pens for each source. There
were two feeding phases including starter (0-21 d) and grower (21-35 d).
At the end of each phase, birds were weighed by pens and two birds per pen
(four birds per pen for the 500 mg kg-1 levels) were killed to
take liver and tibia samples for analysis of Cu concentration. Overall,
there was no effect of Cu source or dietary Cu concentration on feed
conversion or mortality. At 14 d the birds in the MINTREX treatment
weighed significantly more than the birds in the Cu sulfate treatment.
High Cu concentrations markedly decreased (p<0.0001) body weight
regardless of Cu sources in both phases. Elevated dietary Cu concentration
significantly increased (p<0.01) tibia ash Cu concentration for both Cu
sources in both phases; however there was no good linear relationship
between tibia Cu accumulation and non-zero Cu consumption. There were
marked effects (p<0.05) of Cu source, concentration and their
interaction on 14 d dry liver Cu concentration. Based on dry liver Cu
concentration regressed on non-zero copper consumption, the relative
bioavailability of MINTREX Cu was 111.63% for 14 d and 110.71% for 35 d
when bioavailability of reagent grade Cu sulfate was set as 100%. This
indicated that MINTREX Cu source has greater biological availability than
reagent grade Cu sulfate for broilers. |
|
|
|
|
Zurong Wang
,
Sandro Cerrate
,
Cesar Coto
,
Frances Yan
and
Park W. Waldroup
|
|
A study was conducted to evaluate the use of constant or
increasing levels of Distillers Dried Grains with Solubles (DDGS) in diets
for broilers. Diets were formulated for starter (0-14 d), grower (14 to 35
d) and finisher (35 to 42 d) periods to contain 0, 15, or 30% DDGS. Diets
were formulated on digestible amino acid basis to meet current U.S.
poultry industry nutrient levels and were maintained isocaloric and
isonitrogenous. Varying levels of DDGS were fed during the study; with
some birds receiving a constant level while others received increasing
amounts as the bird aged. The DDGS levels used in the study were as
follows (starter-grower-finisher, %): 1) 0-0-0; 2) 0-15-15; 3) 0-15-30; 4)
0-30-30; 5) 15-15-15; 6) 15-15-30; 7) 15-30-30; 8) 30-30-30. Starter diets
were crumbled, while grower and finisher diets were pelleted. Each of the
dietary treatments was fed to four replicate pens of 25 birds each. Body
weights and feed consumption were determined at 14, 35 and 42 d of age. At
the conclusion of the study five representative birds were processed for
dressing percentage and parts yield. The results indicated that increasing
DDGS levels had a trend to reduce the weight:volume ratio and visually
decreased pellet quality. Diets containing 15% DDGS could be fed
throughout the entire feeding period of 1 to 42 d of age with no adverse
effects on live performance or carcass composition when diets were
formulated on a digestible amino acid basis. Inclusion of 30% DDGS in the
diet reduced the weight:volume ratio and markedly reduced pellet quality.
Birds fed diets with 30% DDGS during the starter or grower periods had
reduced body weight, elevated feed conversion and typically had reduced
breast meat yield, compared to birds fed diets with 15% DDGS or birds fed
the control diet with no DDGS. Feeding DDGS for the last seven days prior
to slaughter after being fed diets with 15% during starter or grower
period might possibly be acceptable in terms of body weight gain and feed
conversion but still resulted in a significant reduction in breast meat
yield. It is possible that some of the essential amino acids that were not
considered in the formulation of the diets may become marginal or
deficient in diets with 30% DDGS. Further studies are suggested to
evaluate needs for these amino acids in diets with high levels of DDGS. |
|
|
|
|
Cesar Coto
,
S. Cerate
,
Z. Wang
,
F. Yan
and
P.W. Waldroup
|
|
A study was conducted to evaluate the carryover effect of maternal vitamin D level and source on performance and bone development of the progeny. Breeder hens were fed a vitamin D deficient diet for two months to deplete stores. After this period, experimental diets in a factorial arrangement were fed to the hens with five levels of cholecalciferol (0, 300, 600, 1200 and 2400 IU/kg) and two levels of 25OHD3 (HyD) (0 and 68 μg/kg) for a total of 10 treatments. At the end of two months on the experimental diets two sets of eggs were hatched. The progeny obtained were placed in battery brooders to 21 days by maternal diet and received a common diet. The first hatch received a diet with no vitamin D supplement whereas the second hatch received a diet with the same nutrient composition but containing 5500 IU/kg of cholecalciferol. The first set of birds responded to the maternal diet supplementation of vitamin D mostly during the first week post hatch with no clear pattern in later stages. The progeny receiving 5500 IU/kg of vitamin D in the diet responded to the maternal vitamin D supplementation even at 21 days and in a clearer trend. Feed conversion and body weight improved as the cholecalciferol level increased and with the inclusion of HyD in the maternal diet. The response when HyD was added was more noticeable at low levels of cholecalciferol supplementation with no difference at higher levels in the hens diet. Bone development of the progeny was improved with the addition of HyD in the maternal diet; this response was not influenced by increasing levels of cholecalciferol in the breeder diet. This study confirms the importance of the maternal vitamin D carryover for an adequate development of the progeny. Certainly, the vitamin D carryover effect did not overcome the effect of supplementing vitamin D directly in the progenys diet but it was capable of improving the performance of the progeny even three weeks post-hatch when a high level of cholecalciferol (5500 IU/kg) was present in the diet of the progeny. A carryover effect of HyD when added to the maternal diet was observed in this study, thus the feasibility of using the metabolite to supply vitamin D to the developing embryo was confirmed. |
|
|
|
|
Cesar Coto
,
S. Cerate
,
Z. Wang
,
F. Yan
,
Y. Min
,
F.P. Costa
and
P.W. Waldroup
|
|
A study was conducted to evaluate the effect of the vitamin D level and source on the performance of broiler breeders and the deposition of this vitamin in egg yolk. Pullets reaching sexual maturity were depleted of vitamin D stores by feeding a vitamin D deficient diet during an eight week period. Following depletion, an experimental design was utilized consisting of a 5 x 2 factorial arrangement with four levels of dietary cholecalciferol (0, 300, 600, 1200 and 2400 IU/kg) and two levels of 25-hydroxycholecalciferol (25-OH, supplied as HyD) (0 and 68 μg/kg) for a total of 10 treatments. Each experimental diet was fed to two pens with 10 hens and 2 roosters that each received the experimental diets. Levels of 25-OH in plasma and in egg yolk were measured right after the depletion period and during the experimental phase. Performance parameters such as body weight, hen-day production, egg-shell thickness and egg mass were measured weekly. After the depletion period the level of 25-OH in plasma and egg yolk was below the detection limit confirming the depletion status. During the experimental phase the amount of 25-OH in plasma and egg yolk was higher as the cholecalciferol increased. When HyD was fed the level of 25-OH in plasma and egg yolk was higher than obtained when cholecalciferol was fed. Increasing levels of cholecalciferol improved egg shell thickness, hen-day production and egg mass. The addition of HyD improved egg-shell thickness, hen-day production and egg mass. The effect of HyD on performance was more noticeable at low levels of cholecalciferol with no difference at higher levels of cholecalciferol in the diet. |
|
|
|
|
|
|