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1.
This study was conducted to evaluate vitamin E injection and Se in a mineral supplement in late gestation on lamb survival and pre-weaning growth performance. Ewes were grouped in pens based on their fetal count and BW. The feed provided to ewes in late gestation included alfalfa hay, corn, and protein supplement according to NRC (1985) recommendations. Ewes in late gestation were assigned to a 2 × 2 factorial arrangement of treatments within fetal count (single, twin, and triplet + quad). Treatments were no vitamin E or 900 IU of vitamin E injected i.m. per week and 10 or 90 ppm of Se in a mineral supplement fed ad libitum. Within each pen of ewes (8 to 10 head), approximately one-half of the ewes received injectable E beginning 4 wk before the first expected lambing; the other one-half received no vitamin E. Vitamin E treatments ended at lambing time; however, ewes remained on their respective mineral sources during lactation. Lambs were provided access to creep (16% CP, 83% TDN, and fortified with 35,000 IU of vitamin E, 0.27 g of Se, and 50 g of chlortetracycline/909 kg of creep feed) initiated at an average 10 d of age to weaning. Weekly injection of 900 IU of vitamin E did not affect birth BW (BBW) of lambs. However, 90 ppm of Se fed ad libitum improved BBW of lambs (5.06 vs 4.88 kg, P<0.10) with all of the improvement occurring in lambs born to 6- to 7-yr-old ewes (P<0.01). Vitamin E increased (P<0.05) the pre-weaning performance of lambs from 1- to 2- and 6- to 7-yr-old ewes but did not improve the performance in lambs from 3- to 5-yr-old ewes. Multiple-birth lambs from ewes treated with vitamin E had increased survival in 1 of 2 experimental yr (P<0.05). Survival of single-birth lambs was not effected by vitamin E or Se treatment. These results demonstrate that supplementation of 90 ppm of Se fed ad libitum to ewes during late gestation and throughout lactation improved BBW of lambs from 6- to 7-yr-old ewes, and weekly injection of 900 IU of vitamin E to ewes during late gestation increased the pre-weaning growth of lambs from 1- to 2- and 6- to 7-yr-old ewes and may increase the survival of multiple-birth lambs.  相似文献   

2.
In vitro glucose uptake and protein synthesis were measured using serum from feedlot steers fed diets supplemented with organic Cr (OCr); glucose clearance was studied using sheep as a model. Treatments investigated for glucose uptake and protein synthesis were 1) control (0 ppm supplemental Cr), 2) 0.2 ppm supplemental OCr from high Cr yeast, and 3) 0.4 ppm supplemental OCr from high Cr yeast that contained 2,000 ppm Cr (2 mg Cr/g Saccharomyces cerevisiae yeast) added to a 90% concentrate feedlot diet. The form of OCr supplied by high Cr yeast is presumably a glucose tolerance factor (GTF), which potentiates the action of insulin, and consists of Cr3+ centrally bound to or associated with cysteine, glutamate, glycine, and nicotinic acid residues. Serum harvested from steers fed 0.2- and 0.4-ppm OCr diets increased (P<0.05) protein synthesis in primary bovine muscle cultures. Glucose uptake rate by muscle cell cultures was increased (P<0.09) by serum from OCr-supplemented steers. Treatments investigated for glucose clearance by lambs were 1) control (0 ppm supplemental Cr), 2) 0.2 ppm, 3) 0.4 ppm, and 4) 0.8 ppm supplemental OCr from high Cr yeast added to a 85% concentrate finishing diet. Glucose clearance in lambs was improved (P<0.05) by addition of 0.2 and 0.8 ppm OCr to the diet. These results are interpreted to suggest that increased carcass muscling in ruminants fed OCr-supplemented diets is a result of improvements in amino acid uptake and glucose metabolism within muscle cells.  相似文献   

3.
Four ruminally and duodenally cannulated Suffolk wether lambs (34.5 +/- 2 kg initial BW) were used in a 4 x 4 Latin square designed experiment to compare effects of supplemental ruminally degradable protein (RDP) vs. increasing amounts of supplemental ruminally undegradable protein (RUP) on ruminal characteristics and site and extent of digestion in lambs. Lambs were fed a basal diet of crested wheatgrass hay (4.2% CP) for ad libitum consumption, plus 1 of 4 protein supplements: isolated soy protein (RDP source) fed to meet estimated RDP requirements assuming a microbial efficiency of 11% of TDN (CON) or corn gluten meal (RUP source) fed at 50, 100, or 150% of the supplemental N provided by CON (C50, C100, and C150, respectively). Neither NDF nor ADF intake was affected (P >/= 0.18) by protein degradability, but they increased or tended to increase (P /= 0.26) for CON and C100, but increased (P /= 0.33) by protein degradability. However, true ruminal N digestibility was greater (P = 0.03) for CON compared with C100. Ruminal ammonia concentrations were greater (P = 0.002) for CON compared with C100 lambs, and increased (P = 0.001) with increasing RUP. Microbial N flows were not affected (P >/= 0.12) by protein degradability or increasing RUP. Likewise, neither ruminal urease activity (P >/= 0.11) nor microbial efficiency (P >/= 0.50) were affected by protein degradability or level of RUP. Total tract OM, NDF, and ADF digestibility was greater (P 相似文献   

4.
Objectives of this study were to evaluate synchronization, conception, and pregnancy rates of heifers synchronized with melengestrol acetate (MGA)-prostaglandin F2α (PGF2α,), Select Synch, or Select Synch preceded by MGA (MGA-Select Synch). Heifers in the MGA-PGF2α group (n = 209; BW = 378 kg) received MGA (0.5 mg/ d per heifer) for 14 d and PGF2α (25 mg) 19 d later. Select Synch heifers (n = 213; BW = 374 kg) received gonadotropin-releasing hormone (GnRH; 100 μg) followed by PGF2α (25 mg) 7 d later. The MGA-Select Synch heifers (n = 210; BW = 373 kg) were fed MGA (0.5 mg/d per heifer) for 7 d, GnRH (100 μg) the day following the last MGA feeding, and PGF2α (25 mg) 7 d after GnRH. More (P<0.01) heifers were in estrus 1 to 4 d before PGF2a administration in both the Select Synch (20%) and MGA-Select Synch (24%) groups than in the MGA-PGF2α (4%) group. Pregnancy rates for heifers in estrus early (d 1 to 4 before PGF2α) were greater (P<0.05) for both Select Synch (55%) and MGA-Select Synch (63%) compared with MGA-PGF2α heifers (18%). Synchronization rate (detected after PGF2α) was greater (P<0.01) for MGA-PGF2α heifers (86%) compared with Select Synch (66%) and MGA-Select Synch (68%) heifers; however, conception rate did not differ (P=0.13) and averaged 72, 63, and 62% for MGA-PGF2α, Select Synch, and MGA-Select Synch heifers, respectively. Select Synch (52%), MGA-Select Synch (58%), and MGA-PGF2α protocols (61%) provided similar (P=0.18) overall AI pregnancy rates; however, more heifers were in estrus before PGF2α administration in protocols using GnRH.  相似文献   

5.
Yearling Angus bulls (n = 325) were allotted by BW into six pens of equal size. One of three dietary treatments consisting of 1) dietary Zn at 40 ppm, all supplied by zinc sulfate (ZnS); 2) dietary Zn at 40 ppm with 33.3% supplied by zinc proteinate and 66.6% supplied by ZnS (ZnPS); or 3) dietary Zn at 60 ppm, all supplied by ZnS (ZnHi) was delivered to two pen replicates. Initial and final liver biopsies were collected and analyzed for Zn concentration. Scrotal circumference and BW measures were collected at the start and conclusion of the trial. Semen from bulls intended for public sale (n = 167) was collected and evaluated for motility and morphological abnormalities. Bulls with percent normal sperm cell counts < 70% or with motility scores less than fair (motility scores = poor, fair, good, and very good) were considered classification deferred (CD). Following 126 d of treatment, bulls on the ZnHi treatment had a greater (P=0.06) increase in liver Zn concentration than bulls on the ZnS treatment, but not bulls on the ZnPS treatment (P=0.18) (‒9.8, 1.2, and 20.6 ppm for ZnS, ZnPS, and Zn Hi, respectively). No differences in scrotal circumference or ADG were detected. Bulls receiving ZnPS had higher (P<0.05) percent normal sperm cells than did bulls receiving ZnS, but not bulls receiving ZnHi (55.5, 68.9, and 62.5% for ZnS, ZnPS, and ZnHi, respectively). The frequency of CD was less (P<0.05) for bulls on ZnPS and ZnHi treatments than for bulls on the ZnS treatment. In all fertility measures observed in this trial, bulls receiving the ZnPS rated greatest, followed by bulls on ZnHi, and lastly by bulls on ZnS.  相似文献   

6.
Two experiments were conducted to determine the effects of supplemental zinc (Zn) from an organic and an inorganic source on growth performance, serum Zn concentrations, and immune response of beef calves. Treatments consisted of: i) control (no supplemental Zn), ii) Zn sulfate, or iii) Zn–amino acid complex. Zinc sources were supplemented to provide 360 mg of Zn/d. Experiment 1 was a 28-d study using 84 steers (240 ± 1.5 kg) fed bermudagrass hay (21 mg Zn/kg DM) with 1.8 kg/d of the appropriate corn-based supplement. In Exp. 2, 75 heifers (176 ± 2.5 kg) were fed bermudagrass hay (38 mg Zn/kg DM) and the supplements for 140 d. In Exp. 1, ADG was greater (P<0.05) from d 15 to 28 in calves fed supplemental Zn-amino acid compared with those fed Zn sulfate, but ADG did not differ (P>0.10) among treatments for the entire 28-d study. In Exp. 2, there was no effect (P>0.10) on ADG as a result of Zn supplementation. In Exp. 2, Zn-supplemented heifers had a greater response (P=0.06) to phytohemagglutinin 24 h after an intradermal injection. In Exp. 2, calves supplemented with Zn–amino acid complex had a greater antibody response to a second vaccination for bovine respiratory syncytial virus than did control or Zn sulfate-supplemented calves (treatment by day interaction, P=0.06). There was not a consistent benefit of supplemental Zn on growth of calves, but there was a positive impact of supplemental Zn on some immune-response measurements.  相似文献   

7.
A study was conducted to compare the effects of three supplemental zinc sources on beef steers grazing winter annual pasture and during receiving in a feedlot. In southern Arkansas, 84 steers were weighed (BW = 216 ± 1.5 kg), bled via jugular puncture, and randomly assigned to 12 bermudagrass pastures (0.81 ha each) that had been overseeded with wheat, rye, and annual ryegrass (7 steers per pasture; 116 d of grazing) on January 15; the steers were allowed to graze until May 11. Steers were fed 0.45 kg daily of corn-based supplement containing 103 mg zinc from ZnSO4, zinc amino acid complex (ZnAA), or zinc polysaccharide (ZnPOL) during the entire grazing period. On May 12, steers were shipped to a research feedlot (14 h; 1,016 km; 6.9% BW shrink) in northeast New Mexico. In the feedlot, the same groups of steers were fed a receiving diet (steam-flaked milo) that contained the same zinc sources as fed during the grazing period. Dietary concentrate was increased from 75 to 85% of dietary DM weekly. Data were analyzed as a completely random design; least squares means were separated using contrast. Steer BW on d 28 and 84 of the grazing period were greater (P<0.05) for cattle fed ZnAA and ZnPOL than for steers fed ZnSO4; however, ADG over the 116 d of grazing and ending BW did not differ (P>0.28) among zinc sources. In the feedlot, steer BW, ADG, and feed efficiency did not differ (P>0.05) among zinc sources. Serum zinc concentrations did not differ (P>0.05) among zinc sources at any point in time. We conclude that early in the grazing period, ZnAA and ZnPOL improved steer BW compared with ZnSO4; however, no differences were noted among zinc sources later in the grazing period or during receiving in the feedlot.  相似文献   

8.
Two experiments were conducted to determine effects of supplemental ruminally degradable protein (RDP) vs. increasing amounts of supplemental ruminally undegradable protein (RUP) on intake, apparent digestibility, N retention, and nutrient flux across visceral tissues in lambs fed low-quality forage. Lambs were fed a basal diet of crested wheatgrass hay (4.2% CP) for ad libitum consumption, plus 1 of 4 protein supplements: isolated soy protein (RDP source) fed to meet estimated RDP requirements (CON), or corn gluten meal (RUP source) fed at 50, 100, or 150% of the supplemental N provided by CON (C50, C100, and C150, respectively). In Exp. 1, 12 lambs (29.9 +/- 2.7 kg) were used. Forage OM intake was not affected (P = 0.46) by protein degradability or by increasing RUP (P >/= 0.31). Apparent total tract OM digestibility was not affected (P = 0.10) by protein degradability, but increased (P /= 0.40) by protein degradability or level of RUP. In Exp. 2, 16 catheterized lambs (32 +/- 5 kg) were used. Net release of ammonia-N from the portal-drained viscera (PDV) was greater (P = 0.02) for CON than for C100 and increased linearly (P = 0.002) as RUP increased. Net uptake of ammonia-N by liver was not affected (P = 0.23) by protein degradability, but increased linearly (P = 0.04) as RUP increased. Net urea-N release from liver was not affected (P >/= 0.49) by protein degradability or level of RUP. Net uptake of urea-N by PDV was greater (P = 0.02) for C100 compared with CON and increased (P = 0.04) with increasing RUP. Neither net release from PDV nor hepatic uptake of alpha-amino N were affected (P >/= 0.12) by protein degradability or level of RUP. Hepatic ammonia-N uptake accounted for 82, 38, 98, and 79% of net urea-N release from the liver for CON, C50, C100, and C150, respectively. Hepatic alpha-amino N uptake for all treatments greatly exceeded that required for the remaining urea-N release by the liver, suggesting that alpha-amino N may serve as a temporary means of storing excess N by liver between supplementation events. The pattern of net release or uptake of N metabolites between supplementation events requires further investigation.  相似文献   

9.
Although pigs will readily consume wet food waste (FW), the high moisture content contributes to spoilage and feeding management problems. The use of a dry, processed FW product was compared with a traditional corn and soybean (CS) diet using growing swine in two performance trials and one digestibility trial. The FW diet contained approximately 20% processed FW (DM basis). In Trial 1, 24 gilts (76.4 kg) housed in eight replicated pens (four pens per treatment) were fed in a 6-wk trial. Intake, BW gain, feed efficiency, and carcass characteristics were compared. Feed intake and BW gain averaged 3.4 and 3.6 kg of DM/d and 0.87 and 0.85 kg/d for gilts fed traditional and FW diets, respectively. There were no differences in these or any other measurements (P>0.05). In Trial 2, 12 barrows (84.3 kg) housed in four replicated pens (two pens per treatment) were fed in a 6-wk trial. Intake, BW gain, feed efficiency, and carcass characteristics were compared. Feed intake and BW gain averaged 3.1 and 3.3 kg of DM/d and 0.62 and 0.71 kg/d for barrows fed traditional and FW diets, respectively. Four growing gilts (68.2 kg) were used to compare digestibility in a crossover design. There were no differences (P>0.10) for DM, CP, ADF, or NDF digestibility when feed intake averaged 1.9 kg of DM/d for both FW and CS diets. The use of up to 20% processed FW may be suitable in commercial swine diets.  相似文献   

10.
Using growing calves (n = 368) grazing mature forage in three 84-d experiments, one objective was to compare the effects of feeding molasses-based liquid supplements containing urea (U) alone or combined with fish solubles (FS), fish meal (FM), or feather meal (FE) on performance, and blood metabolites. Another objective was to evaluate the effects on these criteria of adding carnitine to these supplements to provide 1 g·h−1·d−1 L-carnitine. Including FM or FE in the mixture improved (P<0.05) supplement consumption in two experiments and improved growth rate in all experiments. Carnitine improved the growth rate when U was the only protein source, but reduced growth rate when FM was included in the liquid supplement (P<0.05). During the growth phase, plasma ammonia N (PAN) was higher (P<0.05) when U was the only protein source as compared with FM or FE. Carnitine did not influence these metabolic parameters. During the metabolic phase of each experiment, calves similar to those used in the growth phase were dosed via stomach tube with 3 g liquid supplement/kg BW. Ruminal and blood samples were collected at 0, 0.5, 1, 2, and 4 h after dosing. Ruminal ammonia N, PAN, and plasma urea N (PUN) concentrations were higher (P<0.05) when calves were dosed with U or FS supplement than when dosed with FM or FE supplements. Calves dosed with liquid supplement containing carnitine had lower (P<0.05) concentrations of ruminal ammonia N and PAN. Carnitine reduced (P<0.05) PUN in one experiment and increased (P<0.05) PUN in another. Branched-chain volatile fatty acids were increased (P<0.05) by dosing with FS or FM supplements. Including ruminally undegradable protein sources (FM or FE) in liquid supplement improved intake and performance and was related to reduced ruminal ammonia N, PAN, and PUN. Carnitine fed in liquid supplement also reduced ruminal ammonia N and PAN concentrations.  相似文献   

11.
Forty-eight Angus and Angus-cross steers (initial BW = 657 ± 5.7 kg) were used in a 2 × 2 factorial design to determine whether feeding an anionic diet or high dietary concentrations of a soluble calcium (Ca propionate) source or both would alter Ca metabolism and subsequently longissimus tenderness. Treatments consisted of 1) control, 2) 4% Ca propionate (CaProp), 3) 2% NH 4Cl (anionic diet), and 4) CaProp plus 2% NH4Cl. Experimental diets were fed for 7 d prior to slaughter. Steers were individually fed using electronic Calan gate feeders. Blood samples were obtained on d 3 and 7 at 2 h post feeding for plasma Ca determination. A striploin steak was obtained from each carcass at 48 h post harvest for muscle Ca analysis and Warner-Bratzler shear force (WBSF) determination. Addition of CaProp or NH4Cl to the high concentrate finishing diet reduced (P < 0.01) ADG and DMI during the 7-d feeding period. The anionic diet reduced ADG to a greater extent than did CaProp. Average daily gain and DMI were lowest for steers fed both NH4Cl and CaProp, indicating that their effects were additive. Carcass characteristics were not affected by CaProp, but the anionic diet tended to reduce hot carcass weights (P=0.13) and longissimus areas (P=0.09). Plasma Ca concentrations were slightly greater in steers fed CaProp on d 3 (P < 0.10) and 7 (P < 0.01) of the study. The anionic diet did not affect plasma Ca. Muscle Ca concentrations and WBSF values were not affected by either CaProp or the anionic diet. Results indicate that beef tenderness was not enhanced in steers fed a diet high in CaProp or those fed an anionic diet.  相似文献   

12.
The objective was to determine the effects of duration of progestin exposure prior to gonadotropin treatment on the synchronization of estrus and fertility in gilts. Gilts were fed daily a complete diet containing 15 mg Regu-mate® (Intervet America Inc., Millsboro, DE) for 14 (n = 19) or 18 (n = 18) d. Twenty-four hours after the last feeding of Regu-mate®, all gilts received an i.m. injection of P.G. 600® [400IU pregnant mare serum gonadotropin (PMSG) and 200 IU human chorionic gonadotropin (hCG); Intervet America Inc.]. Gilts were bred artificially 12 and 24 h after first detection of standing estrus. More 18-d (33.3%) than 14-d treated gilts (5.3%) were in estrus on the peak day (d 4.0) after P.G. 600® injection (P=0.02). The percentage of gilts displaying estrus < 7 d after P. G. 600® injection was greater (P=0.06) for the 18-d treatment (88.9%) than for the 14-d treatment (63.2%). Farrowing rate tended to be greater (P=0.17) for gilts exposed to Regu-mate® for 18 d (75%) compared with 14 d (50%). Total pigs born (P=0.43), pigs born live (P=0.63), stillborns (P=0.62), and total litter weight (P=0.52) were similar between groups. The number of mummified fetuses tended to be higher (P=0.11) for gilts in the 18-d treatment group (0.8 ± 0.2) compared with the 14-d treatment group (0.2 ± 0.3). In summary, the precision of estrus synchronization and reproduction was greater in gilts given P.G. 600® after 18 d compared with 14-d Regu-mate® treatment.  相似文献   

13.
The aim of this study was to investigate the development of the pupillary light reflex and menace response in neonatal lambs and goat kids. Thirty lambs and 33 kids were assessed daily from birth until the pupillary light reflex and menace response had become established. All animals had a controlled pupillary light reflex within 20 h of birth. Lambs and kids had developed menace responses by 8 ± 3 and 14 ± 2 days, respectively. The Mann–Whitney test revealed a significant difference (P < 0.001) in the ages at which lambs and kids developed a menace response. Male kids developed this response significantly (P = 0.006) later than females. There was no sex difference in the menace response in the lambs. Overall, the findings indicated that lambs develop a menace response earlier than kids, and female kids develop this response more rapidly than their male counterparts.  相似文献   

14.
Supplement placement can be used to manipulate livestock grazing patterns. The objective of this case study was to compare the effect of low-moisture blocks (LMB) and range cake (barley-based cylindrical cubes, 2 cm in diameter, and 2 to 8 cm long) supplementation on cattle grazing patterns in Montana foothill rangeland. One group of nonlactating cows (n = 79) was fed cake 3 times per week (1.8 kg · cow−1 · feeding−1), and the other group (n = 81) had continuous access to LMB in separate pastures using a crossover design. Movement patterns of cows were recorded with global positioning system collars during four periods (2 wk · period−1) during autumn. Range cake was fed on accessible areas, and LMB were placed in higher and steeper terrain. Intake of LMB averaged (mean ± SE) 318 ± 50 g · d−1. Cows fed LMB (8.07° ± 0.20°) were observed on steeper slopes (P = 0.08) than cows fed range cake (6.96° ± 0.19°). Forage utilization decreased as slope increased to a greater degree when range cake was fed than when LMB was fed (P = 0.001). Cows spent more time (P = 0.05) within 100 m of LMB (274 ± 23 min · d−1) than at range cake feeding sites (67 ± 24 min · d−1). Strategic placement of LMB on high, steep terrain appears to be a more practical and effective approach than traditional hand-feeding range cake on intermediate terrain to improve uniformity of cattle grazing on rugged rangeland.  相似文献   

15.
Mixed breed steers (n = 96; 211 ± 1.48 kg) were used for a 35-d trial to determine the effects of amprolium and supplemental thiamin on thiamin status and growth performance of stressed cattle. Amprolium at 0 or 5 mg/kg initial BW and thiamin at 0 or 140 mg/kg DM were fed in a 2 × 2 factorial arrangement of treatments. Amprolium was top-dressed on the daily feed for the first 21 d of the study; each steer had 50-cm bunk space available. Steers were kept in 3.7 m × 30.5 m drylots (n = 16; 6 steers per pen and 4 pens per treatment) and were fed a corn, soybean meal, cottonseed hull-based total mixed ration. A pen was used as the experimental unit. Steers fed amprolium had increased ADG from d 0 to 7 (P<0.01). Supplemental thiamin tended to increase ADG from d 0 to 21 (P<0.10). Blood thiamin monophosphate (TMP) concentrations were affected by a sampling day × supplemental thiamin interaction (P<0.001). Blood TMP concentrations were increased by supplemental thiamin on d 7, 14, 21, and 28 (P<0.001) and tended to be increased on d 35 (P=0.08). A sampling day × amprolium interaction was detected for TMP (P<0.05) and blood thiamin pyrophosphate (TPP; P<0.05) concentrations. Blood TMP and TPP concentrations were decreased on d 14, 21, and 28 (P<0.05) in the steers fed amprolium, but amprolium did not affect (P>0.10) TMP and TPP concentrations on d 7 and 35. Thiamin supplementation had no effect on the number of coccidial oocysts in feces, but steers fed amprolium had reduced numbers of coccidial oocysts (P<0.05). Supplemental thiamin and amprolium did not improve overall ADG, ADFI, or gain to feed for the 35-d trial.  相似文献   

16.
The objective of this study was to evaluate synchronization and pregnancy rates of beef heifers supplemented with 0.91 kg of whole sunflower seeds for 0, 30, or 60 d before AI. Beef heifers from four locations (n = 1,014) were assigned by BW to treatment (within location) and randomly to AI sire. Heifers at Location 1 (n = 176; mean BW = 332 kg) received either 0- or 60-d sunflower seed treatments. Heifers at Location 2 (n = 397; mean BW = 334 kg) were fed sunflower seeds for 0, 30, or 60 d. Heifers at Locations 3 (n = 211; mean BW = 345 kg) and 4 (n = 230; mean BW = 343 kg) received 0- or 30-d sunflower seed treatments. Within location, diets were formulated to be isocaloric and isonitrogenous. All heifers received melengesterol acetate (0.5 mg/d per head) for 14 d followed 19 d later by an injection of prostaglandin F2a (PGF) (25 mg). Heifers were bred by AI according to the AM/PM rule except on d 3 when all heifers that had not exhibited estrus were artificially inseminated in mass. Neither 72-h estrous response nor pregnancy rate was affected (P>0.10) by 30- or 60-d sunflower feeding. In summary, feeding 0.91 kg of whole sunflower seeds for either 30 or 60 d before AI did not improve estrous response or pregnancy rate when compared with controls.  相似文献   

17.
The objective of this study was to evaluate the effect of forage concentration on sorting, nutrient intake and feeding behaviour of growing lambs. Twelve weaned lambs were exposed, in a crossover design with 7‐day periods, to each of two treatment diets: (i) lower‐concentrate diet (LC; 40.0% concentrate) and (ii) a higher‐concentrate diet (HC; 60.0% concentrate). Alfalfa hay was used as forage source. Sorting was determined by subjecting fresh feed and ort samples to particle separation and expressing the actual intake of each particle fraction as a percentage of the predicted intake of that fraction. Lambs sorted against long particles (>19 mm) on both treatments. On the LC diet, lambs sorted for medium particles, whereas animals fed the HC diet did not sort for or against medium particles. Lambs sorted for fine particles (<1.18 mm) on both treatments (p < .05). The extent of sorting for the fine particles was greater on the LC diet compared with the HC diet (p < .05). Dry matter intake was increased by increasing the concentrate content of the diet. Intake per visit and eating rate increased, and total chewing time was decreased in lambs fed HC diet. In conclusion, lambs sorted most against the longest particles and for the fine particles. Furthermore, feed sorting behaviour is affected by the forage level, and lambs sorted more for the fine particles in the LC diet.  相似文献   

18.
A comparative slaughter experiment was conducted with 28 Spanish kids (BW = 20.6 kg) fed a hay-based diet to determine the effects of supplemental energy and protein on growth rate, body composition, and ruminal and blood metabolites. After 84 d, kids were harvested, digesta contents removed and empty body weighed and ground. Samples were freeze-dried and analyzed for DM, CP, ether extract, ash, and gross energy. All kids had increased BW gains. However, unsupplemented kids lost empty BW and weight of all body components except ash. Kids supplemented with energy or protein increased (P<0.05) empty BW, body water, protein, fat, ash, and gross energy when compared with unsupplemented kids. The percentages of body water and ash decreased (P<0.05) when supplemental energy or protein was fed. The percentage of body protein was reduced (P<0.05) by supplemental energy and unaffected (P=0.81) by supplemental protein. Supplemental energy reduced (P<0.05) ruminal acetate and increased (P<0.05) propionate and butyrate. Supplemental protein increased (P<0.05) concentrations of ruminal ammonia N, plasma urea N, and all ruminal volatile fatty acids. Regression equations suggest that intake of 144 kcal of ME and 6.0 g of CP per kilogram of empty BW0.75 are necessary to maintain empty BW.  相似文献   

19.
Three 5-wk growth trials involving 288 weanling pigs were conducted to assess the efficacy of three feed additives as alternatives to antimicrobial feed additives. In Trial 1, a mannanoligosaccha-ride (MOS) source was evaluated with the antimicrobial feed additive carbadox. Treatments included 1) a control diet, 2) a diet containing MOS (0.3% during wk 1 and 0.2% for wk 2 through 5), 3) a diet containing carbadox (55 ppm), and 4) a diet containing both additives. For the 5-wk trial, ADG was 446, 450, 489, and 489 g, and ADFI was 770, 769, 840, and 826 g for Treatments 1 through 4, respectively. No effects of MOS supplementation and no interaction effects of MOS and carbadox were observed (P>0.40). Dietary addition of carbadox resulted in an 8% increase in feed consumption and a 9% improvement in growth rate (P<0.01). In Trial 2, a probiotic consisting of Bacillus licheniformis and subtilis was assessed. Treatments included 1) a control diet, 2) a diet containing Bacillus additive (0.1%), 3) a diet containing carbadox (55 ppm), and 4) a diet containing both additives. Overall ADG was 483, 458, 521, and 503 g, and ADFI was 779, 759, 818, and 795 for Treatments 1 through 4, respectively. Overall there was no Bacillus × carbadox interaction (P>0.40). A slight reduction in growth rate with Bacillus supplementation was observed (P<0.05). Carbadox improved growth rate by 9% and improved feed conversion efficiency by 4% (P<0.01). In Trial 3, increasing dietary levels of a polyaspartate biopolymer product (PAB) (0, 100, 200, and 400 ppm) were assessed. Overall ADG was 502, 491, 491, and 513 g, and ADFI was 889, 836, 823, and 866 for the 0, 100, 200, and 400 ppm PAB treatments, respectively. There was a quadratic change in ADFI with increasing PAB level (P<0.06), but no other effect of PAB was observed. Under the conditions of these trials, no improvements in growth performance with the alternative feed additive products were observed. The antimicrobial feed additive carbadox was effective in improving weanling pig growth performance.  相似文献   

20.
Two experiments were conducted (Exp. 1, n = 63; Exp. 2, n = 72) using Angus x Hereford cows grazing Oklahoma dormant tallgrass prairie to determine the effects of increasing supplemental undegradable intake protein (UIP) on performance. In each experiment following parturition (February and March), cows were blocked by body weight, body condition score (BCS), and calving date and randomly assigned to one of four dietary treatments. For Exp. 1, supplements provided 396 g/d of degradable intake protein (DIP) with increasing amounts of UIP (211, 274, 337, and 400 g/d, respectively). For Exp. 2, supplements provided 281 g/d of DIP with 142, 196, 248, and 301 g/d UIP, respectively. Cows were individually fed 1.59 kg supplement 6 d/wk. Body weight and BCS were determined biweekly until the end of supplementation (Exp. 1, 37 + 1.5 d; Exp. 2, 45 + 1.2 d). Milk production was estimated 30 and 45 d postpartum. Plasma progesterone concentrations were quantified weekly to determine interval to first normal luteal function (PPI). Weight loss, BCS, and PPI were not influenced by treatment. In Exp. 2, there was a linear (P<0.08) decrease in weight gain of calves post-treatment to weaning as supplemental UIP increased, and a quadratic effect (P<0.06) of additional UIP on milk production at 30 d postpartum. In these experiments, metabolizable protein requirements were met by microbial protein, forage UIP, and a minimum of 142 g of supplemental UIP.  相似文献   

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