Research has shown that trace elements, such as Se, Mn, and Zn, can alter reproductive functions. The aim of the current study was to evaluate the sperm quality index (SQI) and sperm viability as affected by various levels and sources of Se, Mn, and Zn when added in vitro to broiler breeder semen. In vitro treatments consisted of the following sources and levels of minerals: Control, no minerals added to sperm; seleno L-methionine, 4 levels ranging from 8.78 to 7,896 microg/L; sodium selenite, 4 levels ranging from 8.78 to 7,896 microg/L; MnSO4, 8 levels ranging from 6,500 to 65,000 mg/L; Zn 180 (Zinpro Corporation), 4 levels ranging from 0.65 to 650 mg/L; and ZnSO4, 4 levels ranging from 0.65 to 650 mg/L. The addition of 7,896 microg of sodium selenite/L to semen was detrimental to sperm motility. Also, MnSO4 adversely affected SQI and sperm viability at concentrations of 6,500 mg/L and greater. Sperm viability was decreased when 650 mg/L of Zn 180 was added to semen. Sperm motility was depressed by exposure to Zn 180 at 650 mg/L and ZnSO4 at 65 and 650 mg/L. Our results suggest that these trace minerals must act at the reproductive tissue level during spermatogenesis to improve semen quality. Direct in vitro application of these elements to semen appears to be detrimental to spermatozoa.

1. Ross 308 broiler breeder hens were given diets containing 0 or 25 mg L-carnitine/kg from 21 weeks of age.2. Hens were inseminated with semen from Ross broiler breeder males and subsequent growth performance and carcase traits, of progeny obtained from hatches at 30, 35 and 37 weeks of age, were evaluated.3. Progeny were hatched in a common facility and separated by gender. Experimental treatments employed for the 30-, 35- and 37-week hatches, respectively, were: hen diet and progeny gender (16 replications with two subplots); hen diet, progeny diet (0 and 50 mg L-carnitine/kg of diet) and progeny gender (16 replications with 4 subplots); and hen diet and progeny diet (high and low density; 16 replications with two subplots).4. Females had lower growth rate and less breast meat, but greater proportions of carcase fat and breast meat than males. Growth performance measurements of progeny were not affected by hen L-carnitine, but hen L-carnitine decreased abdominal fat in progeny. Increasing diet density in the chick diets increased growth and carcase weights. Hen and progeny dietary L-carnitine interacted to increase male mortality. However, dietary hen L-carnitine decreased carcase fat and increased breast meat in progeny fed on high nutrient density diets.5. In conclusion, L-carnitine in the diet of hens affected carcase traits of their progeny.

The Thr needs in 3 commercial broiler strains (A, multipurpose; B, high yield; C, high yield) known to differ in terms of feed intake, growth rate, and breast yield were evaluated. Birds were randomized across 96 floor pens (12 birds/pen), received a common diet from d 1 to 20, and were fed graduations of Thr (0.52 to 0.87% total Thr in 0.07% increments) from d 21 to 42. Treatments (3 × 6 factorial) were replicated 5 or 6 times. The corn, soybean meal, and peanut meal test diet contained 0.43 and 0.96% digestible Thr and Lys, respectively. An additional group of strain C birds (6 pens) was maintained on a corn-soybean meal diet containing surfeit Thr (0.73% of diet). Birds fed the corn and soybean meal diet performed similarly (P < or = 0.05) to birds fed peanut meal diets. A feed conversion interaction (P < or = 0.05) occurred indicating that strain C was more sensitive to Thr deficiency than strains A and B. The abdominal fat interaction (P < or = 0.05) indicated that strain A had more relative abdominal fat than strains B and C. All strains differed (P < or = 0.05) in terms of BW gain (A, 78.2; B, 75.1; C, 72.9 g/d). Strain C had the lowest (P < or = 0.05) feed intake, which resulted in the lowest (P < 0.05) Thr intake, but it had the highest (P < or = 0.05) breast meat yield. Most parameters tested yielded quadratic (P < or = 0.05) models whereby Thr estimates could be predicted. Namely, BW gain and breast meat yield resulted in total Thr estimates (95% of maximum response) of 0.74 and 0.71%, respectively, which are in close agreement with the 1994 NRC (0.74%). The plasma Thr sigmoid response verified the former estimates. Analysis of strain intercepts and slopes as affected by Thr differed (P < or = 0.05) in terms of feed intake but not BW gain or breast meat yield. The 21 to 42 d Thr need across strains was estimated as 0.74% total or 0.65% digestible. Because dietary Lys was not in excess of the bird’s needs, the former digestibility estimate equated to a Thr/Lys of 0.68.

Two experiments were conducted to evaluate Ile responses in female broilers. In experiment 1, dietary Ile was 0.42 or 0.72% total of diet. Diets were fed to 3 broiler strains: multipurpose Arbor Acres+, high-yield Ross 508, and high-yield Ross 708. In experiment 2, dietary Ile dose responses (0.42 to 0.82% total of diet in 0.08% increments) were evaluated. A corn-soybean meal control (0.70%) diet was used in experiment 2 (6 replications). No Ile x strain interactions occurred. Feeding broilers 0.42% Ile suppressed (P < 0.05) BW gain, feed intake, feed conversion, and breast and thigh yields. Arbor Acres+ strain had a higher BW gain and feed intake (P < 0.05) than the Ross 508 and 708 strains. Differences (P < 0.05) among strains were observed in breast and drumstick yields; Ross 708 broilers had increased breast and drumstick yields in comparison to birds from the Arbor Acres+ and Ross 508 strains. Birds fed surfeit Ile in the titration diets grew as well as (P < 0.05) the birds fed the control diet. Quadratic responses (P < 0.05; 95% of response) were obtained for BW gain (0.67%), feed intake (0.66%), feed conversion (0.68%), and breast meat yield (0.63`%). The 30- to 42-d Ile need for female broilers is between 0.63 and 0.68% of total diet (0.59 to 0.64% digestible Ile).

This research was conducted to evaluate immunity (experiments 1 to 3), cardiac function, and ascities resistance (experiment 4) of progeny chicks from broiler breeders fed diets differing in trace metal level and source. Broiler breeders received a control diet (75 mg of Zn and 83 mg of Mn added/kg of diet), the control diet supplemented with inorganic Zn (75 mg/kg of diet) and Mn (80 mg/kg of diet), the control diet supplemented with organic Zn (75 mg/kg of diet) and inorganic Mn (80 mg/kg of diet), or the control diet supplemented with organic Zn (75 mg/kg of diet) and Mn (80 mg/kg of diet) in experiments 1, 2, and 3. In experiment 4, the control diet and diet supplemented with organic sources of Zn and Mn were fed to broiler breeders. Immune organ weights, circulating granulocytes vs. agranulocytes, CD4 and CD8 positive T cells, cutaneous basophil hypersensitivity, and antibody titers to SRBC and breeder vaccinations were measured in progeny. Some supplemental mineral treatments increased (P < or = 0.05) cutaneous basophil hypersensitivity and relative bursa weight. All supplemental mineral treatments increased (P < or = 0.05) relative thymus weight. In experiment 4, electrocardiograph, pulse oximetry, heart rate, hematocrits, ventricle weights, and ascites incidence were measured in progeny reared in a cold-stress environment. The supplemental organic minerals increased (P < or = 0.05) left ventricle plus septum and total ventricular weights. Although progeny ascites incidence did not differ between breeder mineral treatments, breeders fed supplemental Zn and Mn sired progeny with improved cardiac functional capacity and some improvements in immunity.

S Wednesday, July 28, 2004 POSTER PRESENTATIONS * Author Presenting Paper

A concern of nutritionists and live production personnel is to improve early flock livability and growth rate of broilers. Improvements in progeny performance through trace metal supplementation in the hen's diet may be a method to accomplish this. The focus of this experiment was to evaluate live performance and carcass parameters of progeny from broiler breeders fed diets containing different levels and forms of Zn and Mn. Cobb 500 breeders received a control diet or diets containing supplemental Zn and Mn from inorganic sources, amino acid complexes, or a combination of the two. Body weight gain, feed conversion ratio, livability, percentage carcass without giblets, percentage abdominal fat, and percentage breast meat were measured on the progeny of 37-wk-old breeders. Feeding broiler breeders supplemental Zn and Mn from amino acid complexes improved livability of progeny without affecting growth or carcass characteristics. In conclusion, future research should address progeny carryover of Zn and Mn to improve livability during stress or disease conditions.

Underfeeding the amino acid Thr may result in suboptimal growth and carcass development, and overfeeding my result in increased diet cost. Adequate knowledge of Thr may be more important in finishing broilers due to increased feed consumption and increased maintenance needs. However, published reports on Thr in the finishing period (d 42 to 56) are few, and recommended requirement estimates vary from 0.60 to 0.75% total Thr. This study was conducted to better understand Thr needs during the 42-to-56-d period in broilers reared in different environmental conditions. Live performance and carcass responses of Cobb male broilers as affected by graduations of Thr were evaluated in clean or dirty floor pen environments. Quadratic responses for live performance and breast meat weight were generated for birds reared in the clean environment and ranged from 0.63 to 0.68% total Thr (0.56 to 0.61% digestible Thr). In contrast, birds reared in the dirty environment responded to Thr in a positive linear manner for live performance and carcass traits. One explanation for birds responding to higher levels of Thr in the dirty environment might have been an increased Thr need for gastrointestinal function.

Sound knowledge of amino acid needs for heavy broilers is critical in order to optimize profitability in the further processing market. Although research has delineated requirement estimates for the most limiting amino acids for heavy males, research concerning amino acid needs for females for the further processing market is limited. This study examined Thr, the third limiting. amino acid, needs in. Cobb 500 females from 42 to 56 d of age.Experiment l demonstrated that birds fed the test diet (corn, soybean meal, and peanut meal based) containing added Thr to 0.66% performed as well as birds receiving a traditional corn and soybean meal diet formulated to contain 0.66% Thr. Experiment 2 (0.45 to 0.80% total. Thr in 0.07% increments) and experiment 3 (0.52 to 0.72% total Thr in 0.04% increments) were conducted to establish dose responses to Thr for growth and carcass responses. Threonine had minimal effects on carcass attributes (experiments 2 and 3). A total dietary Thr level of 0.60% supported good growth in experiment 2. In experiment 3, however; good growth was attained in birds fed a total dietary Thr level of 0.67% of diet. These results indicate that the 1994 NRC Thr recommendation (0.68% of diet) from 42 to 56 d is safe for female broilers.

Better environmentally controlled broiler houses have resulted in many integrated broiler operations using the same dietary feed formulations in winter and summer months due to only minor differences in environmental temperature in the broiler house. Much research has addressed broiler nutrient needs in thermoneutral vs. hot temperature conditions, but research evaluating nutrient needs of broilers during moderate temperature conditions (tunnel-ventilated houses during summer months) is lacking. This study evaluates the impact of increasing dietary Lys and other essential amino acids, and the addition of dietary sodium bicarbonate in high and moderate temperature conditions. Experiment 1 was conducted in batteries and evaluated broiler nutritional responses (d 20 to 40) in hot-cyclic temperature conditions (26 to 34°C). Experiment 2 was conducted in floor pens and evaluated broiler nutritional responses (d 37 to 49) in environmental temperature ranges that mimic a tunnel-ventilated broiler house during summer months (26 to 31°C). In both experiments, dietary treatments had minimal impact on live performance and breast meat yield. Lower mortality (P < 0.06), however, was observed in broilers fed the low CP diet in the hot temperature environment.

SUMMARY Sound knowledge of amino acid needs for heavy broilers is critical in order to optimize profitability in the further processing market. Although research has delineated requirement estimates for the most limiting amino acids for heavy males, research concerning amino acid needs for females for the further processing market is limited. This study examined Thr, the third limiting amino acid, needs in Cobb 500 females from 42 to 56 d of age. Experiment 1 demonstrated that birds fed the test diet (corn, soybean meal, and peanut meal based) containing added Thr to 0.66% performed as well as birds receiving a traditional corn and soybean meal diet formulated to contain 0.66% Thr. Experiment 2 (0.45 to 0.80% total Thr in 0.07% increments) and experiment 3 (0.52 to 0.72% total Thr in 0.04% increments) were conducted to establish dose responses to Thr for growth and carcass responses. Threonine had minimal effects on carcass attributes (experiments 2 and 3). A total dietary Thr level of 0.60% supported good growth in experiment 2. In experiment 3, however, good growth was attained in birds fed a total dietary Thr level of 0.67% of diet. These results indicate that the 1994 NRC Thr recommendation (0.68% of diet) from 42 to 56 d is safe for female broilers.