The role of knowledge and perceived susceptibility in intentions to optimize fertility: findings from the International Fertility Decision-Making Study (IFDMS).

STUDY QUESTION: What is the role of knowledge, perceived vulnerability and level of risk of infertility in women's intentions to take action to improve their chance of becoming pregnant (i.e. by seeking medical and/or non-medical help and making lifestyle changes)? SUMMARY ANSWER: Women younger than age 35 were more likely to intend to take measures to improve their chance of conceiving when they were knowledgeable about fertility and felt susceptible to infertility; however, there was no such association in older women. WHAT IS KNOWN ALREADY: The majority of young adults wish to become parents but many are jeopardizing their chances by engaging in behaviours that decrease fertility (e.g. smoking, not seeking timely medical advice when faced with problems conceiving). Research is needed to establish what motivates people to take steps to optimize their chances of pregnancy. The Health Belief Model (HBM) postulates that knowledge and beliefs about susceptibility to infertility are critical in whether people will engage in fertility-optimizing behaviours. STUDY DESIGN, SIZE AND DURATION: This cross-sectional survey included 1345 childless women (trying to conceive and having never engaged in fertility medical treatment) from the International Fertility Decision-Making Study (IFDMS). PARTICIPANTS/MATERIALS, SETTING, METHODS: Infertility risk factors were determined using the FertiSTAT. The Cardiff Fertility Knowledge Scale (CFKS) assessed fertility knowledge. Perceived susceptibility was defined as whether a fertility problem was suspected. The outcome measure was intentions to optimize one's fertility by making lifestyle changes and/or seeking help. MAIN RESULTS AND THE ROLE OF CHANCE: In this study, 75.5% of women had an infertility risk factor and 60.3% suspected a fertility problem. The average correct score on the CFKS was 51.9%. Intentions to optimize fertility were lower among women who were heavy smokers (P < 0.05) and who had been trying to conceive for a year or over (P < 0.01), while intentions to optimize fertility were greater among those with a higher body mass index or greater knowledge and those who suspected a fertility problem (all P < 0.001). These overall effects were qualified in some subgroups. Heavy smokers were more likely to intend to seek medical help when they had greater knowledge (P < 0.001) and women having difficulty conceiving were more likely to intend to seek medical help if they felt susceptible to infertility (P < 0.001). Heavy smokers who were knowledgeable intended to change their lifestyle only when they felt they had a fertility problem (P < 0.01). Intentions to change were not dependent on knowledge and perceived susceptibility in older women. LIMITATIONS, REASONS FOR CAUTION: The data were cross-sectional and thus we cannot infer causality. The results may have been affected by the sample profile, which was biased towards high levels of perceived susceptibility and low levels of knowledge. WIDER IMPLICATIONS OF THE FINDINGS: To maximize impact, educational campaigns should take into account the presence and type of infertility risk factors in the target audience. STUDY FUNDING/COMPETING INTERESTS: Merck-Serono S. A. Geneva-Switzerland (an affiliate of Merck KGaA Darmstadt, Germany) and the Economic and Social Research Council (ESRC, UK) funded this project (RES-355-25-0038, 'Fertility Pathways Network'). L.B. is funded by a postdoctoral fellowship from the Medical Research Council (MRC) and the ESRC (PTA-037-27-0192). B.F. is funded by an interdisciplinary PhD studentship from the ESRC/MRC (ES/1031790/1). I.T. is an employee of Merck-Serono S.A. Geneva-Switzerland (an affiliate of Merck KGaA Darmstadt, Germany).

Cassandra's prophecy: a psychological perspective. Why we need to do more than just tell women.

The most salient psychological issue in the article 'Cassandra's prophecy' is the lack of fertility knowledge. This lack of knowledge exhibited by both Jane and the medical professionals resulted in a delay in trying to get pregnant and in seeking and receiving appropriate care, ultimately resulting in inadvertent childlessness. We identify five educational initiatives to increase fertility knowledge and personal awareness in order to promote informed decision-making about fertility health issues. These initiatives cover: (i) better sexual education for children; (ii) family planning for young adults that involves value and preference clarification about future parenthood goals; (iii) public health campaigns to increase awareness of the risk factors associated with reduced fertility; (iv) investigation of adherence to fertility guidelines within the medical profession; and (v) clearer information about the benefits and limitations of available fertility treatment. The future of fertility health care must be centred on providing people with information leading to informed choice about all aspects of their own fertility health. Empowerment may mean that people can better optimize their fertility health and be more likely to reach their parenthood goals.

Safety evaluation of combination vinblastine and toceranib phosphate (Palladia®) in dogs: a phase I dose-finding study.

Combining drugs with known single-agent activity that lack overlapping dose-limiting toxicities (DLT) and exert antitumour activity through different mechanisms could improve clinical outcome. As toceranib and vinblastine meet these requisites, a phase I trial was performed in combination in dogs with mast cell tumours. The DLT for the simultaneous combination was neutropenia and the maximally tolerated dose was vinblastine (1.6 mg m(-2) every other week) concurrent with toceranib (3.25 mg kg(-1) PO, every other day). This represents greater than a 50% reduction in dose intensity for vinblastine (compared with single-agent use) and as such does not support this combination based on current drug combination paradigms. Although a strict adherence to dose paradigms speaks against the combination, evidence of significant activity (71% objective response) and enhanced myelosuppression suggest additive or synergistic activity. A prospective randomized evaluation comparing this combination with standard single-agent treatments would seem prudent to interrogate this potential.

Development and preliminary validation of the fertility status awareness tool: FertiSTAT.

BACKGROUND: The aim of our research was to create a fertility status awareness tool (FertiSTAT) that would enable women to gain personalized guidance about reducing risks to their fertility and seeking timely fertility medical advice based on their own lifestyle and reproductive profile. METHODS: Independent risk factors associated with female fertility impairment were identified. Associations between risk indicator and fertility status were examined in 1073 women who completed the Fertility Risk Factors Survey (FRFS) online or in pregnancy termination, antenatal or infertility clinics in the UK, consisting of the FertiSTAT indicators; 49.58% (n = 532) were currently pregnant (78.82% > or = 12 weeks pregnant) and 15.66% (n = 168) were currently infertile (trying to conceive >12 or 6 months if >34 years of age). RESULTS: Twenty-two risk factors were identified from the literature review and expert Delphi consultation. Prevalence of risk factors in the validation sample was similar to general population. Most risks were independently associated with fertility status in logistic regressions and in the expected direction. Discriminant analysis demonstrated that the set of FertiSTAT indicators could correctly classify whether women were currently pregnant or infertile [chi(2)(19) = 204.209, P < 0.001] with a correct classification rate for the overall sample of 85.8% (326/380), 91.0% (n = 243/267) for the currently pregnant and 73.5% (n = 83/113) for the currently infertile. CONCLUSIONS: The main result was the generation of a self-administered, multifactorial tool that can enable women to get personalized fertility guidance. This research and the FertiSTAT provide foundational work for public health campaigns to increase awareness about fertility health.

Effects of zinc and sodium monensin on ruminal degradation of lysine-HCl and liquid 2-hydroxy-4-methylthiobutanoic acid.

Four nonlactating, mature, Holstein cows were fitted with ruminal cannula and used in a 4 x 4 Latin square-designed experiment to evaluate the impact of supplemental Zn and monensin on ruminal degradation of Lys and liquid 2-hydroxy-4-methylthiobutanoic acid (HMB). Cows were fed 4.54 kg (as fed) of alfalfa hay top-dressed with 4.54 kg (as fed) concentrate once daily. Concentrates were formulated to provide 0 or 500 mg/kg of Zn as ZnSO4 and 0 or 40 mg/kg of monensin in the total diet. Zinc supplementation provided approximately 22-fold greater dietary Zn than estimated by NRC requirements. On d 14 of each period, cows were dosed via the rumen cannula with 50 g of HMB and 100 g of Lys-HCl, and the concentrations of Lys and HMB were monitored every 0.5 h for 8 h. Supplemental Zn tended to decrease the proportion of acetate in ruminal fluid postfeeding and increased the proportion of propionate in ruminal fluid postfeeding. Supplemental Zn increased mean fluid passage rate from the rumen. Monensin decreased the proportion of acetate and increased the mean proportion of propionate in ruminal fluid, resulting in a decrease in the ratio of acetate to propionate. Monensin also increased the mean fluid passage rate from the rumen. Neither Zn nor monensin affected the apparent rate of ruminal disappearance of HMB or Lys. However, Zn and monensin interacted to alter the ruminal degradability of free Lys but not HMB. These data indicate that Zn and monensin may interact to alter ruminal degradability of free amino acids.

Effect of phytase addition and dietary calcium and phosphorus levels on plasma metabolites and ileal and total-tract nutrient digestibility in pigs.

Two experiments were conducted to determine the effect of phytase on plasma metabolites and AA and energy digestibility in swine. In Exp. 1, eight barrows (surgery BW = 52 kg) were fitted with steered ileocecal cannulas. The experiment was a Latin rectangle and the treatments were 1) corn-soybean meal diet adequate in Ca and P (0.5% Ca, 0.19% available P [aP]), 2) corn-soybean meal diet with reduced Ca and P (0.4% Ca, 0.09% aP), 3) Diet 1 with 500 phytase units/kg, or 4) Diet 2 with 500 phytase units/kg. Pigs were fed twice daily to a total daily energy intake of 2.6 x maintenance (106 kcal of ME/kg of BW(0.75)). For each ileal digesta sample, digesta samples were collected for two 24-h periods and combined for each pig. The combination of supplementing with phytase and decreasing the concentration of dietary Ca and P increased average ileal AA (P < 0.02), starch (P < 0.02), GE (P < 0.04), and DM (P < 0.03) digestibilities. In Exp. 2, a feeding challenge was conducted with barrows (eight per treatment; average BW of 53 kg). The treatments consisted of a corn-soybean meal diet or corn-soybean meal diet + 500 phytase units per kilogram of diet. In the diet with no phytase, Ca and aP were at 0.50% and 0.19%, respectively, and, in the diet with phytase, Ca and aP were each decreased by 0.12%. A catheter was surgically inserted into the anterior vena cava of each pig 6 d before the start of the feeding challenge. The barrows were penned individually, and the diets were fed for 3 d before the challenge. The pigs were held without feed for 16 h, and blood samples were obtained at -60, -30, and 0 min before the pigs were fed (2% of BW). Blood samples were then collected at 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 150, 180, 210, 240, 270, and 300 min after feeding. Glucose area under the response curve and plasma glucose, insulin, urea N, and total alpha-amino N concentrations were increased (P < 0.05) in pigs fed the diet with reduced Ca and P and the phytase addition. Area under the response curve for insulin, urea N, and total alpha-amino N; insulin:glucose; and plasma NEFA concentration, clearance, and half-life were not affected by diet. In conclusion, the combination of Ca and P reduction and phytase addition increased nutrient and energy digestibility in diets for pigs and increased plasma concentrations of glucose, insulin, urea N, and alpha-amino N.

Adult female rats defend "appropriate" energy intake after adaptation to dietary energy.

OBJECTIVE: To determine if adult female rats adapt to lower and higher dietary energy density. RESEARCH METHODS AND PROCEDURES: Study 1 compared high-fat (56%), high-energy density (HD) (21.6 kJ/g) and high-fat (56%), low-energy density (LD) (16.0 kJ/g) diets before surgery (two groups, 2 weeks, n = 16) and after surgery [ovariectomy (O) Sham (S); 2 x 2 factorial, n = 8; 6 weeks]. The second study (no surgery) compared high-fat (60.0%), high-energy (22.0 kJ/g) and low-fat (10.0%), low-energy (15.1 kJ/g) diets (n = 8). RESULTS: In study 1, food intake was similar for the first 2 weeks, but rats on the LD diet consumed less energy, gained less weight, and had lower nonfasted serum leptin (all p < 0.0001) than rats on the HD diet. After surgery, rats on the LD and HD diets had similar weight gain, but rats on the LD diet consumed more food (p < 0.0001) and less energy (p < 0.009). O rats consumed more food and gained more weight (p < 0.0001) than S rats. Results from study 2 were similar to those from study 1. DISCUSSION: The results demonstrated that O and S surgery rats and rats with no surgery adjust their food intake to defend a level of energy intake. This defense only occurred after a 2-week adaptation period. The major differences in final body weights and abdominal fat resulted from the initial 2 weeks before adaptation to energy density. Rats fed higher-energy diets seemed to "settle" at a higher level of adiposity, and rats fed lower-energy diets consumed more food to increase energy consumption.

Influence of dietary carnitine in growing sheep fed diets containing non-protein nitrogen.

The influence of supplemental L-carnitine was investigated in growing sheep fed rations containing non-protein nitrogen (NPN). The experiment was conducted as a randomized block design with a 2x2 factorial arrangement of treatments. Lambs (77.4kg BW, n=24) were fed a total mixed ration (12.1-13.6% CP) with two levels of L-carnitine (0 or 250ppm) and two levels of NPN (urea contributing 0 or 50% of total dietary N) for a 50-day period. Jugular blood samples were collected at 0, 1, and 3h post-feeding, and ruminal fluid samples were collected at 1h post-feeding, during days 1, 8, 29, and 50 of the experiment. Average daily gain (121 versus 214g) was lower (P<0.0001) in lambs fed the NPN diets. Lambs consuming diets containing NPN had higher (P<0.0001) ruminal fluid pH (6.6 versus 5.9), ruminal ammonia N (4.8 versus 2.8mmol/l), and plasma ammonia N (177.1 versus 49.5µmol/l) than lambs not fed NPN. Additionally, lambs fed the NPN diets had lower plasma urea N (14.5 versus 17.5mmol/l; P<0.003) and thyroxine (T(4)) concentrations (65.8 versus 78.4ng/ml; P<0.02), and lower T(4):triiodothyronine (T(3)) ratio (37.9 versus 43.9; P<0.02). Plasma glucose concentrations were higher (P<0.05) in lambs fed L-carnitine (3.83 versus 3.70mmol/l). Two oral urea load tests (OULT 1 and OULT 2) were conducted during the 50-day trial. Urea solutions (0.835g/kg(0.75) BW) were administered as oral drenches. During the OULT 1 (day 10), plasma ammonia N and glucose concentrations were highest (P<0.0001) in the lambs fed NPN with L-carnitine compared with lambs fed control, L-carnitine, and NPN diets. During the OULT 2 (day 50), plasma ammonia N was highest (P<0.0001) in the NPN and NPN with L-carnitine groups compared with the control and L-carnitine groups. Plasma glucose was lowest (P<0.04) in the NPN with L-carnitine group compared with the NPN and L-carnitine groups, but did not differ (P>0.10) from the control group. Plasma urea N levels in both OULT 1 and OULT 2 were lower (P<0.0001) in the NPN and NPN with L-carnitine groups compared with the control and L-carnitine groups. In the present experiment, production and plasma criteria were affected by NPN incorporation in the diets. Production criteria were not affected by inclusion of L-carnitine in the diet, however, L-carnitine reduced experimentally induced hyperammonemia by day 50 of the trial.

Effects of dietary inclusion of chromium propionate and calcium propionate on glucose disposal and gastrointestinal development in dairy calves.

In experiment 1, 21 male Holstein calves (43.9 kg) were fed only milk replacer at 1.4% of their body weight as dry matter for 6 wk. Dietary treatments included a commercial milk replacer (22% protein, 15% fat) containing (dry basis) either 6.4% Ca propionate or 6.4% dextrose (control) and either 0 or 0.5 mg/kg of supplemental Cr as Cr propionate. Neither Cr nor Ca propionate affected body weight gain; however, Ca propionate tended to increase the growth of the entire foregut measured after slaughter at 6 wk of age. A Minimal Model glucose tolerance test indicated that insulin sensitivity was not affected by treatment. However, calves fed Cr had higher glucose disappearance indexes than controls when propionate was not fed (0.013 vs. 0.019 units) but similar clearance when propionate was included (0.018 vs. 0.018 units, Cr x P interaction). The area under the glucose response curves after propionate-loading tests was much greater for calves fed the Cr versus control replacer when propionate was not present; however, when propionate was included, the response was less dramatic. In experiment 2, 25 Holstein calves were used to study performance and metabolic responses when milk replacer, and then postweaning starter, were supplemented with 0.5 mg/kg of Cr as Cr propionate. The metabolic responses of these calves were not affected by treatment. Overall, combined data suggested that supplemental Cr may improve glucose effectiveness; however, these responses seemed to be attenuated by supplemental propionate.

Influence of intravenous L-carnitine administration in sheep preceding an oral urea drench.

Two experiments were conducted to investigate the effect of i.v. administration of L-carnitine on selected metabolites in sheep and to determine the feasibility of using L-carnitine to ameliorate the deleterious effects of hyperammonemia in sheep. In Exp. 1, i.v. L-carnitine solutions were administered at three levels in a replicated Latin square: 0 (CONT), 6.36 (CAR 1), and 12.72 (CAR 2) mmol L-carnitine/kg x (75) BW using Suffolk ewes (n = 6; average BW 75+/-3 kg). Plasma L-carnitine concentration was increased (P<.05) by treatment (51.9 vs 102.3, and 96.4 micromol/L in CONT, CAR 1, and CAR 2, respectively). Plasma glucose concentration was elevated (P<.05) in CAR 2 and CAR 1. Plasma NEFA concentration was highest (P<.05) in CAR 2. Area under the response curve for glucose was greater (P<.02) in CAR 2. In Exp. 2, Suffolk ewes (n = 16; average BW 48+/-2 kg) were used in a randomized complete block design with a 2x2 factorial treatment arrangement to determine the effects of i.v. L-carnitine administration during an oral urea load test (OULT). L-Carnitine (0 and 6.36 mmol/kg x (75) BW) was administered i.v. at 30 min, and an oral urea drench (50% wt/vol; 0 and 300 mg/kg BW) was administered at 60 min. Plasma L-carnitine was increased (P<.0001) by i.v. L-carnitine. Plasma ammonia N was highest (P<.0001) in the UREA treatment compared with the CONT, CARN, and CARN + UREA treatments (148 vs 95, 101, and 108 micromol/L, respectively). Intravenous L-carnitine administration influenced plasma glucose and NEFA concentrations in sheep and, when administered 30 min preceding an OULT, prevented the development of subclinical hyperammonemia in sheep.

Performance and metabolic responses of young dairy calves fed diets supplemented with chromium tripicolinate.

Forty-two Holstein calves were used to study performance and metabolic responses when milk replacer and then postweaning starter were supplemented with 1 ppm of Cr as Cr-tripicolinate. From birth through 8 wk of age, supplemental Cr tended to improve the growth performance of bull calves but not of heifer calves. Starter intake and feed efficiency were not affected by supplemental Cr. From 1 to 5 wk of age, plasma cortisol concentrations sampled just prior to feeding decreased, and concentrations of insulin-like growth factor-I increased. All calves appeared to become less sensitive to insulin as they aged. From 1 to 5 wk of age, plasma glucose and insulin concentrations gradually diverged for all calves; glucose concentrations decreased, and insulin concentrations increased. In addition, glucose clearance rate, measured by i.v. glucose tolerance tests, was more rapid when calves were 2 wk of age than when calves were 8 wk of age. The glucose clearance rate was greater in heifer calves than in bull calves but was not affected by supplemental Cr. Entry of plasma glucose following an i.v. propionate load was also greater in heifer calves than in bull calves but was not affected by supplemental Cr. Plasma nonesterified fatty acids were lower in calves fed milk replacer or starter supplemented with Cr than in control calves, although this effect diminished as calves aged. This finding was considered to be indirect evidence of enhanced insulin sensitivity in calves fed milk replacer or starter supplemented with Cr. Overall, data suggested that supplemental Cr-tripicolinate had minor effects on the metabolism and growth performance of conventionally managed dairy calves. The most notable effects occurred during the initial few weeks of life.

Seasonal effects of supplemental fat or undegradable protein on the growth and metabolism of Holstein calves.

One summer (heat stress) and one winter (neutral conditions) trial were conducted to assess the effects of varied amounts of RUP and fat on the growth and metabolic responses of calves. In each trial, 190-kg Holstein calves (n = 45) were fed a basal diet of corn and cottonseed hulls supplemented with soybean meal (control) or supplemented with raw or roasted whole soybeans or the basal ration plus prilled hydrogenated tallow either with or without a mixture of feather meal and blood meal. Prilled tallow was more detrimental to fiber digestion and growth performance than were whole soybeans, especially during summer. During winter, calves fed a high (49%) percentage of the dietary CP as RUP had similar BW gain and efficiency of feed usage as did calves fed a moderate percentage (39%), but, during summer, calves fed the high percentage of RUP had greater BW gain and efficiency than did calves fed moderate percentages of RUP. Ruminal concentrations of VFA were parallel to digestibilities of fiber in the total tract. Ruminal concentrations of ammonia or blood concentrations of urea were not consistent with the concentrations of RDP fed. Concentrations of glucose, NEFA, insulin, and thyroid hormones in the blood were primarily affected by season. Data suggested that a higher percentage and AA quality of RUP improved the growth of calves during summer but not during winter.

Dietary protein and energy restriction in mares: rapid changes in plasma metabolite and hormone concentrations during dietary alteration.

Two diets consisting of bermudagrass hay and a corn-cottonseed hull-based supplement were formulated to provide either 100% (control) or 50% (restricted) of the protein and energy requirements for maintenance for mature mares. Twelve light horse mares were fed the control diet for 7 d, and then at 0800 on d 0, six mares were switched to the restricted diet. All diets were fed as two equally sized meals at 0800 and 1600. At 0800 on d 7, mares receiving the restricted diet were switched back to the control diet. Relative to control mares, mares switched to the restricted diet had reduced plasma concentrations of glucose (P = .005) and insulin (P = .09) in response to the two restricted meals on d 0. However, concentrations of both glucose and insulin returned to control levels (P > .1) within 1 h after the consumption of the control diet on d 7. Dietary restriction increased (P = .009) plasma NEFA concentrations within the first 24 h, and NEFA concentrations remained elevated (P < .001) in restricted mares until the mares were returned to the control diet on d 7. Meal-induced increases (P < .05) in plasma concentrations of glucose, insulin, urea N, glucagon, and thyroxine were observed. These results emphasize the importance of early sampling when monitoring plasma constituents during nutrient alterations and indicate that prefeeding responses of plasma constituents alone may not fully explain the metabolic consequences of nutrient restriction.

Feed deprivation of mares: plasma metabolite and hormonal concentrations and responses to exercise.

Twelve light horse mares were fed a control diet that provided 100% of their maintenance protein and energy requirements for 7 d and were then either continued on the control diet or totally deprived of feed (with access to water) for 3 d . Plasma samples were drawn twice daily throughout the experiment, at 15-min intervals for 9 h beginning 45 h after feed removal, and at 10-min intervals around an exercise bout beginning 73 h after feed removal. Feed deprivation increased (P < or = .06) whole blood beta-hydroxybutyrate and plasma NEFA, urea N, L-lactate, and glucagon concentrations, decreased (P = .02) IGF-I concentrations, and did not change (P > .1) plasma glucose insulin, prolactin, triiodothyronine, and thyroxine concentrations. Exercise increased (P < .05) plasma NEFA, prolactin, and growth hormone (GH) concentrations in all mares. Plasma NEFA concentrations increased (P < .001) after exercise and remained increased in fed mares, but rapidly decreased in deprived mares (time x diet interaction, P = .006). Plasma glucose concentrations following exercise increased in deprived mares but decreased in fed mares (time x diet interaction, P = .07). The plasma prolactin response after exercise also differed between groups (P = .09). Feed-deprived mares had greater (P = .02) plasma GH concentrations before exercise (73 h after feed withdrawal) and had a greater (P < .001) GH peak at 10 min after initiation of exercise. The increase in secretion rate o GH due to feed deprivation in these mares was similar to that reported for other domestic species but was not nearly as great in magnitude.

Influence of chromium tripicolinate on glucose metabolism and nutrient partitioning in growing lambs.

Twenty-four Suffolk lambs (average BW 38 +/- 2.7 kg; 16 ewes and 8 wethers) were fed either a corn-cottonseed hull-based control diet (CON) or CON plus 250 ppb of Cr as chromium tripicolinate (CrPic). Lambs were penned in groups of three and ADG and DMI were measured through d 85 of the experiment. Jugular blood samples were obtained during wk 2, 7, and 11. An i.v. glucose tolerance test (IVGTT; 500 mg of glucose/kg BW) and an i.v. insulin challenge test (IVICT; .1 IU of ovine insulin/kg BW) were performed during wk 2 and 10 of the trial. This was followed by a N balance trial during wk 3 and 11. Wethers were slaughtered at the end of the experiment and carcass characteristics determined. No differences (P > .10) were observed between dietary treatments in DMI, ADG, or N balance; however, the CrPic-fed wethers had 18% less fat over the 10th rib (P = .082) and a lower yield grade (P = .014). Plasma NEFA was lower throughout the trial (P < .03) and cholesterol was 17% lower during wk 2 (P < .02) in lambs fed CrPic. There were no differences due to diet (P > .10) in plasma concentrations of urea N, glucose, albumin, total protein, insulin, glucagon, triiodothyronine, or thyroxine. Glucose clearance rate and half-life during the IVGTT and IVICT did not differ (P > .10) between CON and CrPic groups; however, during the IVGTT on wk 2, plasma insulin was elevated (P < .05) and glucose reduced (P = .067) in the lambs fed CrPic. Supplemental CrPic seems to influence metabolic measurements that may affect performance of growing lambs.

Influence of nitrogen fertilization and defoliation frequency on nitrogen constituents and feeding value of annual ryegrass.

Two experiments were conducted to determine the seasonal effects of N fertilizer (NF) and defoliation interval (DI) on specific N fractions within annual ryegrass (AR) and overall usage of AR N by growing lambs. In Exp. 1, NF (0, 112, 224, and 336 kg of N/ha) and DI of 2, 4, or 6 wk were factorially applied to AR plots. Both decreasing DI and increasing NF increased N levels in AR in a manner that depended on harvest date (NF or DI x harvest date interaction, P < .05). The proportions of .2% NaOH soluble N or soluble protein N were not affected (P > .05) by NF or DI. Although NF had no effect (P > .05) on in situ disappearance of DM, decreasing the DI seemed to reduce the severity of the season-induced reduction in DM disappearance (DI x harvest date interaction, P = .04). In Exp. 2, NF (0 or 224 kg of N/ha) and a DI of 2 or 6 wk were factorially applied to AR plots. Fresh, frozen AR was fed in semipurified diets (48% of DM as AR) to four wether lambs (23 +/- 1.3 kg) using a 4 x 4 Latin square. Diets including AR had greater ruminal DM and plant N digestibilities when AR had a 2-wk vs a 6-wk DI with NF but had reduced digestibilities when AR had a 2-wk vs a 6-wk DI without NF.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary protein and(or) energy restriction in mares: plasma growth hormone, IGF-I, prolactin, cortisol, and thyroid hormone responses to feeding, glucose, and epinephrine.

Sixteen light horse mares were fed diets of bermudagrass hay and a corn/cottonseed hull-based supplement formulated to contain either 100% (control) or 50% (restricted) of the protein and(or) energy requirements for maintenance in a 2 x 2 factorial arrangement of treatments. Plasma IGF-I, prolactin, cortisol, triiodothyronine, and thyroxine were monitored for 33 d. On the 27th d, frequent blood samples were drawn throughout the day for the measurement of growth hormone (GH), and on the 29th d, an epinephrine challenge and an i.v. glucose tolerance test (IVGTT) were performed in the morning and afternoon, respectively. Restriction of protein and(or) energy reduced (P < .001) plasma IGF-I concentrations within 24 h, and the effect persisted through the 24th d. Energy restriction decreased (P = .01) plasma cortisol concentrations, whereas thyroid hormones were not influenced (P > .1) by restriction of protein and(or) energy. Plasma prolactin concentrations were low throughout the experiment and after the IVGTT, but they increased (P = .003) after feeding. Protein restriction increased (P = .09) the occurrence of GH episodes during the 14-h feeding period on d 27; the greatest effect occurred in the mares restricted in both nutrients. In contrast, energy restriction reduced (P = .05) the GH response to epinephrine injection. We conclude that 1) protein deficiency in mares increases GH secretion, whereas energy restriction alone does not, 2) a deficiency in energy and(or) protein reduces IGF-I secretion, and 3) prolactin concentrations increase after feeding, even at a time of year when secretion rates are naturally low.

Dietary protein and(or) energy restriction in mares: plasma glucose, insulin, nonesterified fatty acid, and urea nitrogen responses to feeding, glucose, and epinephrine.

Sixteen light horse mares (8 to 9 yr of age; 457 to 579 kg BW) were fed Bermudagrass hay and a corn/cottonseed hull-based supplement formulated to contain either 100% (control) or 50% (restricted) of the protein and(or) energy requirements for maintenance in a 2 x 2 factorial arrangement of treatments. Daily measurements of intake, BW, and plasma hormones and metabolites were made for 33 d. Plasma glucose, insulin, NEFA, and urea N were measured in hourly samples drawn on d 27, and parallel with an i.v. glucose tolerance test (IVGTT) and epinephrine challenge on d 29. Energy restriction increased daily NEFA concentrations (P < .001) and urea N (P = .013), whereas protein restriction decreased (P = .002) urea N concentrations. These effects of protein and energy restriction occurred within 24 h and were consistent (day effect, P > .1) throughout the remaining 24 d. Normal meal consumption elevated plasma glucose, insulin, and urea N concentrations (time effect, P < .08). Plasma NEFA concentrations did not change after feeding in mares fed control energy, but decreased in mares fed restricted energy (energy x time interaction, P = .005). After IVGTT, areas under the curve for plasma glucose and insulin were smaller in mares fed restricted protein (P < .05), whereas glucose area was larger in mares fed restricted energy (P = .009). After epinephrine injection, energy restriction increased the initial magnitude of the NEFA response, but after 50 min, reduced plasma NEFA below pre-injection concentrations (energy x time interaction, P = .06).(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of chromium picolinate on glucose usage and metabolic criteria in growing Holstein calves.

Holstein calves, 10 steers (98 +/- 16 kg; Exp. 1) and 14 heifers (122 +/- 7 kg; Exp. 2), were fed either corn-cottonseed hull basal diets (CON; 15.1 and 13.2% CP, respectively) or CON plus 370 micrograms/kg of Cr as Cr-tripicolinate (CrP). After either 58 (Exp. 1) or 56 (Exp. 2) days of ADG and DMI measurement, calves were individually fed 1.4% of their BW every 12 h through the end of each experiment. Nitrogen balance, i.v. glucose tolerance tests (IVGTT), i.v. insulin challenge tests (IVICT), baseline growth hormone (GH) measurements, and GH-releasing hormone challenges were then performed on calves in split groups on d 70 through 87 in Exp. 1. In Exp. 2, all challenges began on d 78 and N balance was not determined. Inclusion of CrP did not affect (P > .10) ADG, DMI, or ADG/DMI of pooled data from Exp. 1 and 2 or N balance criteria in Exp. 1. Plasma glucose, insulin, and NEFA concentrations were not affected (P > .10) by CrP. Total plasma cholesterol was lower (P < .05) for CrP- than for CON-fed calves at wk 4 in Exp. 1 and wk 6 in Exp. 2. During IVGTT, calves fed CrP vs CON had higher (P < .05) clearance rates for glucose in Exp. 1 (2.68 vs 1.88%/min) and in Exp. 2 (2.64 vs 2.08%/min). During IVICT, calves fed CrP vs CON had higher clearance rates for glucose in Exp. 1 (2.98 vs 2.34%/min; P = .12) and in Exp. 2 (2.89 vs 2.00%/min; P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Parkinson's disease. Quality of life issues.

PD affects many dimensions of quality of life. This article has identified motor and nonmotor features of PD that are directly related to a patient's quality of life. Medication therapy can help to ameliorate some of the symptoms, yet side effects can be as disabling as the symptoms of PD. Nursing care should include assessment, intervention, and evaluation of both physical and psychosocial aspects of care for patients with PD to assist them in achieving maximum functioning.