Phytoremediation of pyrene in a Cecil soil under field conditions.

We evaluated the effects of annual ryegrass (Lolium multiflorum Lam.) and phosphorus (P) availability on the dissipation of pyrene added at a concentration of approximately 600 mg kg-1 dry soil in the top 7.5 cm of a Cecil loamy sand (fine, kaolinitic, thermic Typic Kanhapludults) in a 10-month experiment under field conditions in Clemson, South Carolina. Plastic canopies were installed to prevent flooding of plots and raindrop dispersion of pyrene. Treatment factors were pyrene, vegetation, and available P levels. Each of the eight treatments had four replicates. The soil was adjusted to low and high P concentrations (an average of 41 and 66 kg extractable P ha-1, respectively). After a 175-d lag period for all treatments, the rate of pyrene removal followed first-order kinetics. The first-order rate constant was significantly higher in nonvegetated (0.098 d-1) than vegetated treatments (0.034 d-1). These data suggest that the presence of easily biodegradable organic matter from plant roots slowed the removal rate of pyrene. The levels of available P did not affect the rate of pyrene dissipation. Pyrene decreased below the detection limit of 6.25 mg kg-1 dry soil in all treatments after 301 d.

Influence of Temperature and Wetting Period on Inoculum Production by Monilinia fructicola in Peach Twig Cankers.

Overwintering cankers in peach twigs caused by the brown rot fungus, Monilinia fructicola, were studied to identify the relationships of wetting period and temperature on sporulation. Sporulation was observed on blighted blossoms, peduncles, abscission scars, and cankers resulting from contact with infected fruits. The frequency of sporulation on overwintered infected tissues was greater at 15 and 23°C than at 4 or 11°C. Twelve hours of wetting was sufficient at all temperatures studied (5 to 23°C) for sporulation to occur, but the number of twig cankers supporting sporulation increased with time of wetting up to 72 h. Given the additional moisture requirements for spore germination, ingress, and infection, 17 to 30 h of wetting or high humidity during bloom may be needed for blossom blight to occur unless viable conidia are already present as a result of previous wetting periods.

Stability of dietary ascorbic acid and the effect of supplementation on reproductive performance of broiler breeder chickens.

1. The purpose of the study was to determine the stability of dietary ascorbic acid and the reproductive responses of broiler breeder chickens to supplemental 75 mg ascorbic acid/kg diet. 2. Six breeder flocks of 13,000 birds each were studied. Egg production, eggshell porosity, fertility, hatchability and plasma ascorbic acid were measured. 3. Storage of the diets under dry heat resulted in a linear decrease in ascorbic acid content and the rate of decline was 5-fold higher in the supplemented diet. 4. Differences were not detected between treatments in egg production, egg weight, eggshell porosity, fertility, hatchability or plasma ascorbic acid. 5. The results did not provide evidence of a beneficial reproductive response to the inclusion of ascorbic acid in commercial broiler breeder diets.

A retrospective analysis of factors contributing to calf mortality and dystocia in beef cattle.

Records of 2191 calvings from the Clemson University Beef Physiology Unit between 1981 and 1993 were analyzed to determine factors affecting malpresentation, mortality and dystocia. Only 20 (0.91%) parturitions involved malpresentation: posterior presentation (n = 14), leg deviations (n = 3), head deviations (n = 2) and breech birth (n = 1). Dystocia affected calf mortality within 24 h of birth (P < 0.05), with mortality increasing as the severity of dystocia increased. There was an overall 4.5% death loss within 24 h of birth, with 4 and 7% mortality rates for calves from multiparous and primiparous dams, respectively (P < 0.05). Mortality was higher for bull vs heifer calves (P < 0.05). Ninety-four percent of calvings were unassisted, while 6% were assisted births. Dystocia was greater (P < 0.01) in primiparous (17%) than in multiparous dams (4%). In births involving dystocia, 28.1% required mild traction, 69.3% required heavy traction and 2.6% required Cesarean section. Birth weights associated with normal births and mild traction (36 and 36 kg) were lighter than those associated with heavy traction and Cesarean section (40 and 42 kg, respectively; P < 0.05). In conclusion, malpresentations were too few to be of significance, and dystocia influenced mortality within 24 h of birth. Calf birth weight and parity of dam explained most of the observed variations in dystocia.

Influence of tallow and Aspergillus oryzae fermentation extract in dairy cattle rations.

Objectives were to determine the effects of adding 3 g/d of Aspergillus oryzae fermentation extract to diets with or without 5.6% added tallow. Twenty-eight Holstein cows (mean = 98 d of lactation) were assigned to a randomized block experiment in a 2 x 2 factorial arrangement of treatments. Treatments were the basal diet 1) without tallow or extract, 2) with extract but no tallow, 3) with tallow but no extract, and 4) with tallow and extract. Milk production, dry matter intake, 3.5% fat corrected milk, digestibility of neutral detergent fiber in the total tract were depressed for cows fed tallow. Addition of fermentation extract did not stimulate fiber digestion or milk production of cows fed diets with or without fat. Addition of extract did not overcome depression of fiber digestibility by cows fed tallow.

Interaction of dietary fat and acid detergent fiber diets of lactating dairy cows.

Twenty multiparous and 4 primiparous cows averaging 32 DIM were used in an experiment with a 2 x 2 factorial design for 12 wk to determine whether the response to supplemental choice white grease in the diet was augmented with higher fiber. Treatments were 1) 21% ADF with no added fat; 2) 21% ADF plus 6% added fat; 3) 28% ADF with no added fat; and 4) 28% ADF plus 6% added fat. Addition of fat decreased milk fat percentage and tended to decrease milk protein percentage. An interaction of fat by fiber by week for milk fat percentage suggested that ruminal fermentation was disrupted as the trial progressed when fat was included in the lower fiber diet. This disruption did not occur with the higher fiber diets. Yields of milk and FCM were not affected by treatment. There was no fat by fiber interaction for milk yield, which suggested that the yield response to fat was unaffected by fiber concentration. There were no treatment interactions for results of ruminal fermentation. Fiber increased ruminal acetate and the ratio of acetate to propionate but lowered molar percentages of propionate. Supplemental fat decreased acetate and increased propionate. The ratio of acetate to propionate was significantly decreased when fat was fed.

Effect of ergovaline, loline, and dopamine antagonists on rat pituitary cell prolactin release in vitro.

Cultured rat pituitary cells were studied to: determine the effects of ergovaline and loline on in vitro prolactin release; delineate the agonistic activity of these alkaloids at the D2 dopamine receptor, using 2 selective D2 dopamine receptor antagonists; and compare the efficacy of 2 dopamine receptor antagonists in reversing effects of the treatments on in vitro prolactin secretion. Ergovaline reduced in vitro prolactin release by at least 40% (P < 0.05) at concentrations of 10(-4), 10(-6), and 10(-8) M. However, loline reduced (P < 0.05) prolactin release only at the highest concentration, 10(-4) M. Two standard dopamine agonists, dopamine and alpha-ergocryptine, were used to verify that the inhibitory control mechanisms of in vitro prolactin release were intact. Both compounds reduced prolactin release by at least 40% for concentrations of 10(-4), 10(-6), or 10(-8) M. Selective D2 dopamine receptor antagonists (10(-6) M), domperidone and sulpiride, reversed (P < 0.05) the effect of loline on in vitro prolactin release. However, only domperidone (10(-6) M) was able to reverse (P < 0.05) the effect of ergovaline and only at the lowest ergovaline concentration (10(-8) M). Domperidone was more effective (P < 0.05) in reversing the prolactin-suppressing effect of alpha-ergocryptine than was sulpiride. The dose-response curve for domperidone (cubic fit, P < 0.0001) indicated a threshold concentration (10(-7) M) for reversal of alpha-ergocryptine's (10(-8) M) effect on prolactin release. However, at similar concentration of sulpiride (quadratic fit, P < 0.007), a threshold level was not obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcass and meat sensory traits of steers finished on fescue and clover, summer forage, or for different periods in drylot.

During a 3-yr period 184 steers were allotted to five treatment groups. Group 1 steers were pastured on fescue-clover and slaughtered in the spring at approximately 540 d of age. Group 2 steers were pastured on fescue-clover then placed on summer pasture regimens and slaughtered at approximately 620 d of age. Group 3 steers were treated the same as Group 2 then placed in the drylot for 45 d. Group 4 steers were treated the same as Group 2 steers then placed in the drylot for 75 d. Group 5 steers were placed in drylot after weaning and conditioning and were slaughtered at endpoints that corresponded with those for Group 3. Steers selected for slaughter at each endpoint were those evaluated to have reached the most optimum slaughter weight and finish by project personnel. Carcasses of steers from fescue-clover and summer pasture had lower yield grades and a lower quality grade than carcasses of steers from drylot (P < .05). Carcasses of steers from fescue-clover and summer pasture had a more yellow fat covering than carcasses of steers that received a concentrate (Treatments 3, 4, and 5, P < .0001). Fescue-clover- and summer pasture-fed steers had a higher percentage of lean and a lower percentage of fat in the 9-10-11th rib section than did steers that received concentrate (P < .005). Chemical analysis of the lean tissue of the 9-10-11th rib section indicated that summer pasture-fed steers had a lower percentage of ether extract and higher percentage of moisture than the lean tissue from steers that received concentrate (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Lactational response of Jersey cows to bovine somatotropin administered daily or in a sustained-release formulation.

Twenty-four Jersey cows were administered either 0 or 15.5 mg of bST/d or 310 mg of bST/14 d to determine the effect on milk yield, milk composition, feed intake, and body weight. Administration of bST was from wk 14 through 42 postpartum. Cows were housed in a tie-stall barn and fed for ad libitum intake a TMR adjusted to one of two energy protein densities according to milk yield. Milk yield of cows administered bST daily or by sustained-released vehicle increased 27.6 and 24.7%, respectively, over that of control cows; FCM increased by 30.3 and 26.7%. Percentages of fat and protein in milk were unaffected by bST treatment. Dry matter intake of cows administered bST was greater than that of control cows, whether expressed as kilograms per day or as a percentage of body weight. Apparent efficiency of yield increased in cows administered bST. No significant change in body weight occurred; however, cows administered bST had lower body condition scores at 42 wk postpartum. This trial demonstrated comparable effects of bST on lactational performance when administered daily or in a 14-d sustained-release vehicle.

Use of trenbolone acetate and estradiol in intact and castrate male cattle: effects on growth, serum hormones, and carcass characteristics.

The effects of anabolic implant on growth, carcass characteristics, and serum hormones were examined in 30 young bulls and steers fed a growing diet then a finishing diet. In a 2 X 3 factorial arrangement, steers and bulls received an implant of trenbolone acetate (TBA), TBA and estradiol-17 beta (E2), or no implant. Blood samples were taken serially (every 20 min for 6 h) at intervals during the growing and finishing phases. Percentage of DM, fat, protein, and ash and Warner-Bratzler shear test were measured and taste panel evaluations of the 9-10-11 rib section were obtained. Treatment with TBA and E2 increased weight gain in steers but not in bulls. There were no differences in feed efficiency, serum growth hormone (GH), and cortisol concentrations between bulls and steers or between treated groups and controls in bulls or steers, although during the finishing phase mean GH concentrations in treated steers were twofold higher than in controls and were similar to those in the bull groups. Serum insulin-like growth factor-I (IGF-I) increased twofold during the growing phase, then remained at that level. Steers implanted with TBA and E2, which had the highest gains among the steer groups, had the highest serum GH and IGF-I. Longissimus steaks from bulls treated with TBA alone or TBA and E2 were comparable to steaks from steers in the shear test. Taste panelists found steaks from TBA- and E2-treated bulls to be similar in tenderness and connective tissue to steaks from steers.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth and hormonal response of intact and castrate male cattle to trenbolone acetate and estradiol.

Effects of castration and anabolic implants on weight gain, rib soft tissue composition and serum hormones were studied in cattle using a completely random design with a 2 x 2 factorial arrangement. Half of 16 bulls and 16 steers (Angus or Angus x Brahman) aged 9 mo and weighing 290 kg were treated with an implant (200 mg trenbolone acetate and 24 mg estradiol). Half of each group were not treated with an implant. A growing diet was fed for 95 d and half the animals in each group were slaughtered. Animals in the treated groups were reimplanted with trenbolone acetate and fed a finishing diet for 84 d and slaughtered. Percentage dry matter, fat and protein were determined on soft tissue from the 9-10-11th rib. Two blood samples were collected from each animal every 2 wk. Serum was assayed for five hormones. During the growing phase, untreated and treated bulls and treated steers gained more weight and had leaner rib sections that untreated steers (P less than .05); after the finishing phase, there were no differences among groups. Untreated steers had lower insulin-like growth factor (IGF-I) and higher cortisol concentrations during both phases of growth than untreated bulls did (P less than .05). Treatment with implants increased IGF-I concentrations in steers during both phases and reduced cortisol during the finishing phase.(ABSTRACT TRUNCATED AT 250 WORDS)

Fatigue properties of acrylic bone cement: S-N, P-N, and P-S-N data.

The determination of the fatigue properties of a material is a fundamental criteria in the engineering design process. The fatigue properties are governed by a number of factors, one of which is the inherent scatter in the data. In order to take into account this scatter in the results, the concept of the probability of failure (P) is introduced and interconnected with the well known stress (S) versus number of cycles to failure (N) data. This report determines the S-N curve, P-N curve, and P-S-N contour for the three leading acrylic bone cements: Surgical Simplex P, Zimmer LVC, and Zimmer Regular. Tensile specimens were fabricated according to ASTM D638 specifications and tested in uniaxial, zero-tension fatigue. The resulting stress versus number of cycles to failure data was subjected to a nonlinear least-squares analysis to determine the mathematical expression of the fatigue curve. Statistical analysis showed excellent fit of the data to the predicted curve for estimation of the endurance limit of each cement. The results indicated that Zimmer LVC had the highest endurance limit while the limit of Simplex-P and Zimmer Regular were significantly lower. No significant difference was noted in the endurance limit between Simplex-P and Zimmer Regular. The probability of failure at each stress level was determined with respect to fatigue distribution functions. Using the normal distribution function and previous S-N data, the P-S-N contour was generated for each cement. The P-S-N contour fully describes the fatigue characteristics of the material.

A study of the source of estradiol-17 beta in the bull.

A study was designed to determine if the bull testes secretes estradiol-17 beta, as has been reported for several other species. Two experiments were conducted. In the first experiment, five Angus-sired crossbred bulls were fitted with catheters in the spermatic and jugular veins and sampled every 15 min for six hours. One was bled from three cannula, the third being in the spermatic artery. In the second experiment, these same bulls were castrated and jugular vein blood was collected at timed intervals for two hours. Plasma samples were assayed for estradiol-17 beta (E2) and testosterone (T) using highly specific radioimmunoassays. This experiments gave evidence that: a. Concentrations of E2 were significantly lower (P less than .05) in the jugular vein than the spermatic vein in each of the five bulls, although the mean concentration for all bulls was not great for either vein nor was the difference great between the two veins. In confirmation of past studies, T concentration in the jugular vein was much lower than in the spermatic vein in each bull as was overall mean. b. Removal of the testes caused E2 to decrease during the 25 min post-castration but the difference was not significant (P greater than .05), whereas T decreased 4-fold (P less than .01). During the next 95 min., the concentrations of both hormones increased 3- and 6-fold, respectively, as did cortisol concentration. It is concluded that the bull testes secretes E2, but the secretion is minor to that of T and that another source of both hormones can be the adrenal gland, such as during stress.(ABSTRACT TRUNCATED AT 250 WORDS)

Fatigue testing of acrylic bone cements: statistical concepts and proposed test methodology.

In order to determine the fatigue behavior of a material, a standard procedure and methodology must be proposed and validated. This article describes a standard test method and statistical analysis for describing the fatigue properties of acrylic bone cement. It is proposed that bone cement fatigue data can be subjected to probability of failure (P) analysis and the establishment of a distribution function describing the data. It is also proposed that an Olgive type curve can be used to describe the stress (S) vs. cycles to failure (N) data. These two data sets can then be combined to determine the P-S-N relationship which fully describes the fatigue characteristics of the material.

Breed structure of Senepol cattle.

Data were collected by the Virgin Islands Beef Cattle Improvement Program and the Virgin Islands Agricultural Experiment Station staff to establish the breed structure of the Senepol cattle. Data for the analysis were limited to the two Virgin Islands Senepol breeders with the most complete and largest set of records, representing approximately 65% of the entire Senepol population. Inbreeding (F) and coancestry relationship coefficients (rAB) and the theoretical inbreeding (FT) were determined from each data set and for the combined data from both farms, for each year, ranging from 1947 to 1984 for Annaly Farms, and from 1967 to 1984 for Castle Nugent Farm. The data sets for both farms were examined for the possibility of separation into families. Actual F within the Senepol population was relatively low, averaging less than 1.00%. Some separation into families occurred within Annaly Farms' cattle. The F and FT decreased (1.6 to 0.7% and 1.0 to 0.2%, respectively) as population numbers increased. The low F was accomplished through the breeding programs and exchanges of animals between farms on the island.

Sex differences in plasma cortisol and growth in the bovine.

Tame, pubescent beef calves (six bulls; six heifers) were used to examine the relationship between sex, increase in body weight (BW) and plasma cortisol (C). In bulls (B), plasma testosterone (T) was also examined. The two groups were fed a concentrate to 1.5% BW and Coastal bermudagrass hay ad libitum. From 7 to 12 mo of age, at 28-d intervals, the animals were weighed and jugular vein blood was collected every 15 min for 6 h. Onset of puberty was determined weekly by measuring scrotal circumference in B and assaying for plasma progesterone in the heifers (H). Acceptable growth occurred in both B (.83 kg/d) and H (.67 kg/d). These growth rates were different (P less than .02). Plasma C concentrations were significantly different between the sexes over the time span examined. Whereas C remained between 1.6 and 1.8 ng/ml between 7 and 12 mo of age in B, C rose from 2.9 to 6.0 ng/ml in H. The experiment means for B and H were 2.8 +/- .3 (mean +/- SE) and 5.7 +/- .4 (P less than .01). There were significant correlations between plasma C and age or weight in H, but not in B. Mean plasma T in B was greatest at 9 and 10 mo of age (1.4 and 1.3 ng/ml) and lowest at 7 and 12 mo of age (.76 and .74 ng/ml). Plasma T was not correlated with plasma C or age. The lower plasma C concentrations in B compared with H is commensurate with the greater growth that occurred in B.(ABSTRACT TRUNCATED AT 250 WORDS)

Induced gonadotropin release in adrenocorticotropin-treated bulls and steers.

The effect of adrenocorticotropin hormone (ACTH) on plasma cortisol and on gonadotropin releasing hormone (GnRH)-induced release of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone was determined in nine Holstein bulls and 12 Holstein steers. Treatments consisted of animals receiving either GnRH (200 micrograms, Group G), ACTH (.45 IU/kg BW, Group A) or a combination of ACTH followed 2 h later by GnRH (Group AG). Group G steers and bulls had elevated plasma LH and FSH within .5 h after GnRH injection and plasma testosterone was increased by 1 h after GnRH injection in bulls. In Group A, plasma cortisol was elevated by .5 h after ACTH injection in both steers and bulls, but plasma LH and FSH were unaffected. In Group A bulls, testosterone was reduced after ACTH injection. In Group AG, ACTH caused an immediate increase in plasma cortisol in both steers and bulls, but did not affect the increase in either plasma LH or FSH in response to GnRH in steers. In Group AG bulls, ACTH did not prevent an increase in either plasma LH, FSH or testosterone in response to GnRH compared with basal concentrations. However, magnitude of systemic FSH response was reduced compared with response in Group G bulls, but plasma LH and testosterone were not reduced. The results indicate that ACTH caused an increase in plasma cortisol, but did not adversely affect LH or FSH response to GnRH in steers and bulls. Further, while testosterone was decreased after ACTH alone, neither ACTH nor resulting increased plasma cortisol resulted in decreased testosterone production in the bull after GnRH stimulation.

Performance of calves fed milk replacer once daily at various fluid intakes and dry matter concentrations.

Ninety-six Holstein calves were fed 1 of 12 liquid diets once daily under two feeding options. Diets consisted of milk replacer (22% crude protein, 10% fat) fed at fluid intakes of 6, 8, and 10% body weight and dry matter concentrations of 10, 13, 16, and 19%. Feeding options consisted of calculating fluid intake and dry matter concentration based on initial weight and holding this constant through weaning or adjusting weekly according to change in body weight. Water and a complete calf starter (minimum 15% crude protein) were available ad libitum. Calves were weaned abruptly at 4 wk of age and observed until 6 wk of age for immediate postweaning performance. Fluid intake and dry matter concentration had a positive effect on weight gain during wk 0 to 4. However, during the immediate postweaning period, gain decreased in calves previously fed replacer at the higher intake. Overall gain (wk 0 to 6) was not affected by fluid intake or dry matter concentration. Starter intake decreased with increasing fluid intake or dry matter concentration during wk 4 and wk 0 to 4. Total intakes of dry matter were not affected by treatment. Incidence of scours increased linearly with dry matter concentration, and both fluid intake and dry matter concentration had a positive linear effect on fecal score and duration of scours. Feeding option had no effect on any measures. Calves fed replacer containing between 10 and 13% dry matter and offered at 8% body weight had fewer intestinal disturbances during the replacer feeding period and obtained recommended gains over the entire 6 wk.

Prolactin and luteinizing hormone (LH) release throughout the postpartum period in the suckled first-calf beef cow.

A study was performed to examine the release patterns of prolactin and LH of young beef cows with one (single calf) or two calves (double calf) throughout the postpartum interval. The effect on prolactin release of intramuscular and intra-carotid administration of lergotrile and intra-carotid administration of L-dopa was also examined. In approximately 50% and 65% of the cases, no prolactin release could be detected after the beginning of or during the suckling stimulus in cows with one or two calves respectively. LH plasma concentrations remained constant throughout the experiment in all animals. The chosen intramuscular lergotrile treatment lowered plasma prolactin concentrations to baseline levels but had no effect on the length of the postpartum interval. No effect on prolactin release was observed by the given intra-carotid treatments of both lergotrile and L-dopa. First postpartum estrus was observed on days 67 and 88 in the single and double calf cows respectively. The number of suckling periods did not change during the postpartum period but their duration decreased during the same period. These results demonstrate that in at least half of the cases the suckling stimulus does not cause a release of prolactin from the pituitary in the young beef cow. Also, the inhibitory effect of suckling on the resumption of ovarian cyclic function postpartum appears to be of a quantitative nature and mediated by a factor other than prolactin.