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Abstract: Poor persistence of perennial ryegrass swards is a common problem; however, there is a lack of long‐term studies to understand the mechanisms associated with poor persistence. This study describes an experiment to test the hypothesis that high ryegrass seeding rates (>18 kg seed per ha) reduce long‐term population persistence because of smaller plant size and poorer survival during the first year after sowing. Four cultivars, representing four functional types of perennial ryegrass, were sown at five seeding rates (equivalent to 6, 12, 18, 24 and 30 kg seed per ha) with white clover in three regions of New Zealand. Swards were monitored for 5 years. No evidence was found to indicate a lack of persistence of ryegrass‐based swards sown at higher seeding rates. During the first year, swards sown at higher seeding rates had greater herbage accumulation (except at the Waikato site), greater ryegrass tiller density and greater ryegrass content. This initial impact of high seeding rates had largely dissipated by the fourth year, resulting in swards with similar annual herbage accumulation, tiller density and botanical composition. Similarly, there were relatively few differences among cultivars for these variables. Although high seeding rates did not negatively impact sward persistence, geographical location did, with strong evidence of ryegrass population decline at the Waikato site for all treatment combinations, some decline in Northland, and stable populations in Canterbury. It is possible that productive perennial ryegrass pastures can only be sustained for 4–5 years in some situations, even when the best ryegrass technology and management practices are used. [ABSTRACT FROM AUTHOR]

The effects of root herbivory at five densities of Sitona lepidus larvae (overall means between 4 and 333 larvae m-2) were assessed over 2 years on newly established perennial ryegrass-white clover swards in a small plot trial. Initial larval establishment in autumn 2003 was positively related to clover content in plots, and there was no significant impact on clover herbage yield in the first year. Nodule damage in winter 2003 increased with larval density, and results suggested an overcompensatory response in nodule production. A 34-35% reduction in clover yield between highest and lowest S. lepidus densities was recorded for both cultivars in the second year, with greatest losses in spring 2004. This coincided with reductions in clover root and stolon weights. Plant parasitic nematodes and grass grub larvae were most abundant in the plots with lowest weevil numbers. These results confirm field observations that S. lepidus is a major pest of pastures. [ABSTRACT FROM AUTHOR]

The effect of monensin and protein on digestion and ruminal fermentation parameters in cows consuming low-quality forage (LQF; 4.1% CP chopped bluestem hay) was evaluated. Four ruminally cannulated cows (637 ± 24 kg BW) were used in a 4 × 4 Latin square design (20 d periods). Treatments were arranged as a 2 × 2 factorial: the first factor was monensin (0 or 200 mg·cow-1·d-1) and the second factor was protein (0 or 0.64 kg·cow-1·d-1 CP provided as cottonseed meal). A carrier supplement (0.23 kg·cow-1·d-1) consisting of ground hay, cracked corn, molasses, salt, dicalcium phosphate, and a commercial mineral premix was provided to all animals and allowed for inclusion of monensin. Animals were housed and individually fed at 0600 h daily. To prevent carryover effects from previous monensin feeding, 14 d were required before sampling. However, to obtain the optimal response from monensin, only 10 d were needed for treatment adaptation. Therefore, during d 1 through 4 of each period, animals were fed LQF with no treatment. Day 5 through 14 allowed for treatment adaptation and d 15 to 20 was used for sample collection. Digestion measurements were taken d 15 through 19. Rumen fluid was collected h 0, 2, 4, 8, 12, 16, and 20 on d 20 for VFA analyses. Data were analyzed using the MIXED procedure in SAS 9.3 (SAS Inst. Inc., Cary, NC) with terms in the model including protein, monensin, and their interaction, with animal and period included as random effects. There was no protein × monensin interaction (P = 0.30) or effect of monensin (P = 0.37) on any digestion parameter measured. Protein increased OM digestibility (P = 0.01), total digestible OM intake (P < 0.01), and total digestible NDF intake (P < 0.01) by 10.7, 112, and 71.2%, respectively. Protein had no effect on NDF digestibility (P = 0.13). A protein × monensin interaction (P = 0.17) or effect of monensin (P = 0.15) was not observed for total VFA concentration. Protein increased (P < 0.01) total VFA concentration by 20.0%. A protein × monensin interaction was observed for the acetate:propionate ratio (P = 0.05), with protein reducing the ratio when no monensin was present and increasing the ratio when monensin was present. No protein × monensin interaction (P = 0.51) was observed for acetate or propionate concentration. Protein had no effect on acetate (P = 0.11) or propionate (P = 0.67). Monensin increased (P = 0.03) propionate concentration by 8.6% but had no effect (P = 0.41) on acetate. Results suggest that protein increases digestibility when feeding a LQF but that no added benefit is observed with monensin inclusion. [ABSTRACT FROM AUTHOR]

There is an increased demand for motivated students, especially those from underrepresented populations, to enter postsecondary STEM fields. Animal science is an innovative curriculum that can motivate students and spark interest in STEM careers. The need for general scientific literacy is continually increasing. To recruit students to such programs, we must understand what motivates them. The purpose of this study was to determine how the post-secondary agriculture students in an introductory course conceptualized their motivation to learn science skills in animal science. A descriptive-correlational research design was utilized with a modified version of the Science Motivation Questionnaire II (SMQ II) used as the survey instrument. The sample population for this study was taken from an introduction to animal science class at a southern Hispanic Serving Institution. After IRB approval, students were asked to complete the SMQ II. An advantage of this questionnaire is that it does not distinguish between science subjects, but focuses on a general motivation to learn science. It has been emphasized by previous research that the instrument can easily be used in all of science. For this study, we replaced the term "science" with "animal science." The 25-question instrument included the following five-item scales: intrinsic motivation, self-determination, self-efficacy, career motivation, and grade motivation. Students respond to each item on a Likert-type rating scale: never (1) to always (5). The reliability of the individual scales assessed by Cronbach's alphas for the modified instrument was: career motivation (d = 0.90), intrinsic motivation (d = 0.89), self-determination (d = 0.88), self-efficacy (d = 0.56), and grade motivation (d = 0.84). The raw scores should be interpreted carefully, as the scales are ordinal. Collected data was entered and analyzed using SPSS version 19 on measures of central tendency and correlations where appropriate. The highest individual science motivation scores for the specific prompts were: Understanding animal science will benefit me in my future career (m = 4.75, SD = .58), Getting a good animal science grade is important to me (m = 4.69, SD = .48), Knowing animal science will give me a career advantage (m = 4.63, SD = .62). The results of this study show the desire students have in knowing a degree will help them in their future career path. [ABSTRACT FROM AUTHOR]

The effect of dietary sulfur on digestibility of feedstuffs is not well defined. The primary objective of this study was to evaluate the effect of dietary sulfur on in vitro true digestibility (IVTD) of various feedstuffs. A secondary objective was to determine the effect of sulfur-treated rumen fluid on IVTD of various feedstuffs. Treatments consisted of 0 (CON) or 0.3% (SUL) sulfur mixed into the ration of 8 Dorper wethers (29.87 ± 0.52 kg BW) consuming a commercial growing ration (Purina Honor Show Chow Show lamb Grower 15% DX Medicated feed) with chopped coastal hay mixed at 90:10%. Wethers were individually housed for the duration of the 56-d trial. Feedstuffs were selected to represent a variety in nutrient quality and included 4 roughages (wheat straw, bluestem hay, coastal hay, and alfalfa hay) and 3 commercial feedlot rations (starter, intermediate, and finisher diets). Ground feedstuff samples containing CON or SUL treatments were weighed into F57 nylon filter bags in quadruplicate. Sheep were slaughtered 56 d after commencing sulfur inclusion. Gastrointestinal tracts were collected during slaughter to allow for rumen fluid collection. Rumen fluid was processed and IVTD protocol was performed in accordance with ANKOM (2005) using an ANKOM DaisyII Incubator. Data were analyzed using the MIXED procedure of SAS 9.3 (SAS Inst. Inc., Cary, NC). An interaction between treatment and feedstuff was not observed (P ≥ 0.64). A main effect of treatment was not observed (P ≥ 0.22). A main effect of feedstuff was observed (P < 0.01) with starter feedlot ration having the greatest IVTD and wheat straw having the lowest. Results suggest that dietary sulfur does not impact IVTD of feedstuffs, but great diversity exists amongst different types of diets. [ABSTRACT FROM AUTHOR]

The effect of including monensin in a protein supplement fed to cattle consuming low-quality forage is not well defined. The objective of this study was to evaluate the effects of monensin and protein supplementation on in situ disappearance kinetics of low-quality forage (LQF; 4.1% CP). Four cannulated cows were used in a 4 × 4 Latin Square design with treatments arranged as a 2 × 2 factorial: the first factor was monensin (0 or 200 mg·hd-1·d-1), and the second factor was protein supplement (0 or 0.64 kg·hd-1·d-1 CP provided as cottonseed meal; CSM). A premix (0.23 kg·hd-1·d-1) consisting of ground hay, cracked corn, molasses, salt, dicalcium phosphate, and a commercial mineral mix, was provided to all animals and allowed for monensin inclusion. Animals were individually housed and fed at 0600 h daily. Prior to sampling, 14 d were required to prevent carryover effects from previous monensin feeding. However, only 10 days of treatment adaptation was required for optimal monensin response. Thus, d 1 to 4 of each period, all animals were provided LQF with no treatment. Day 5 to 14 served as treatment adaptation, and sampling occurred d 15 to 20. Samples of LQF were weighed into 10- by 20-cm polyester bags in replicates of six for each hour. On d 15, bags were placed into the ventral area of rumen and replicates removed after 0, 4, 8, 16, 24, 48, 72, and 96 h of incubation. Upon removal from the rumen, bags were placed in ice water, rinsed, and then frozen until final bag removal. Bags were washed in a commercial washing machine and then dried at 55°C to a constant weight. Dried residues were analyzed for DM. In situ rumen DM degradation data were fitted to the first-order exponential model with discrete lag using the iterative Marquardt method and NLIN procedure of SAS 9.3. There was no interaction (P ≥ 0.16) between protein and monensin for any DM disappearance parameters measured. Protein had a tendency (P = 0.07) to reduce potentially degradable DM (from 58.60 to 50.42%) likely due to the increased (P ≤ 0.01) rate of DM degradation (from 1.87 to 4.76%/h) that it caused. Monensin had no effect (P = 0.12) on potentially degradable DM but increased (P = 0.03) rate of degradation from 3.06 to 3.57%/h. Protein or monensin supplementation had no effect on lag time or residue (P ≥ 0.11). It is likely that the increased rate of degradation caused by protein and monensin will allow increased intake of LQF, thus improving its use in production operations. [ABSTRACT FROM AUTHOR]

It is believed that sulfur may reduce palatability of lamb, but the resulting effect on digestibility is not clear. The primary objective of this study was to evaluate the effect of dietary sulfur on in vitro true digestibility (IVTD) of a commercial ration fed to 8 Dorper wethers (29.87 ± 0.52 kg BW). A secondary objective was to determine the effect of sulfur-treated rumen fluid on digestibility of diets containing 2 levels of sulfur. Treatments consisted of 0 (CON) or 0.3% (SUL) sulfur mixed into the ration of 8 Dorper wethers (29.87 ± 0.52 kg BW) consuming a commercial growing ration (Purina Honor Show Chow Show lamb Grower 15% DX Medicated feed) with chopped coastal hay mixed at 90:10%. Wethers were individually housed for the duration of the 56-d trial. Ground feedstuff samples containing CON or SUL treatments were weighed into F57 nylon filter bags in quadruplicate. Sheep were slaughtered 56 d after commencing sulfur inclusion. Gastrointestinal tracts were collected during slaughter to allow for rumen fluid collection. Rumen fluid was processed and IVTD protocol performed in accordance with ANKOM (2005) using an ANKOM DaisyII Incubator. Data were analyzed using the MIXED procedure of SAS 9.3 (SAS Inst. Inc., Cary, NC). Sulfur had no effect (P = 0.16; 85.20 vs. 83.00% IVTD, respectively) on IVTD of CON vs. SUL feedstuffs. Rumen fluid from SUL sheep did not differ in its ability to degrade feedstuffs when compared with rumen fluid from CON sheep (P = 0.81; 84.37 vs. 83.83% IVTD for CON vs. SUL rumen fluid, respectively). Results suggest that dietary sulfur could be altered to benefit lamb palatability without affecting digestibility. [ABSTRACT FROM AUTHOR]

The host status of 15 commonly occurring pasture species for Helicotylenchus pseudorobustus was tested in a greenhouse trial. Only tall fescue, with and without Neotyphodium endophyte infection, was a good host (Pf/Pi = final/initial population > 1). Inoculation survival was tested in a second trial, which showed that only 10% of the H. pseudorobustus nematodes survived the first 7 days after inoculation. When the Pf/Pi was adjusted to account for a 10% survival, all of the grass and clover hosts tested had a Pf/Pi > 1. Both trials showed a positive correlation between increased numbers of H. pseudorobustus and free-living nematodes.

The current investigation examined the validity of the Comprehensive Test of Nonverbal Intelligence (CTONI), an intelligence test that is purported to measure fluid intelligence. The CTONI was evaluated in comparison with the Kaufman Adolescent and Adult Intelligence Test (KAIT), an established measure of fluid and crystallized intelligence. Ninety-seven adults were administered these instruments in counterbalanced order. Results indicated that the sample's mean CTONI Nonverbal IQ (NIQ) deviated significantly from the mean KAIT Crystallized, Fluid, and Composite IQs. The CTONI mean NIQ underestimated KAIT Fluid and Composite IQs when individual participants were subdivided into existing KAIT ability categories and mean score comparisons were made. Results also indicated that the CTONI NIQ correlated strongly and positively with the KAIT Composite and Fluid IQs. Furthermore, the CTONI Geometric NIQ scale clearly demonstrated discriminant and convergent validity, whereas, the CTONI Pictorial NIQ (PNIQ) did not.

This study examined the relationship between the Peabody Picture Vocabulary Test-Third Edition (PPVT-III) and Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) using 40 adults who ranged in age from 18 to 41 (mean age of 22 years). Participants were administered the PPVT-III and WAIS-III in counterbalanced fashion to control for order effects. Results revealed that the PPVT-III score was related to the WAIS-III Verbal IQ (VIQ) and Full Scale IQ (FSIQ) scores but unrelated to the Performance IQ (PIQ) score. In addition, analyses indicated that, while there were no significant differences between the PPVT-III score and WAIS-III mean FSIQ and PIQ scores, the PPVT-III mean score was significantly lower than the WAIS-III VIQ. Further analysis indicated that the PPVT-III adequately estimated WAIS-III FSIQ and VIQ scores for participants who were classified as Average or High Average on the WAIS-III. However, for participants in the Superior range, the PPVT-III tended to underestimate FSIQ and VIQ scores by approximately 10 points., (Copyright 2001 John Wiley & Sons, Inc.)

This study examined the validity of a parent-report inventory, the Child Development Inventory (CDI), as a developmental screening instrument in high-risk toddlers and preschoolers. Seventy-six children, aged 15-70 months, were assessed in a neonatal high-risk developmental follow-up clinic. The data included the completion of CDIs by parents/caregivers and developmental evaluations by a physician using either the Clinical Adaptive Test/Clinical Linguistic Auditory Milestone Scale (CAT/CLAMS) (15-35 months) or Slosson Intelligence Test (36-70 months). Analysis revealed a good level of sensitivity (true "abnormals"--73%) and specificity (true "normals"--87%) for the CDI General Development score. The findings suggested that the CDI is a valid and useful screening instrument for high-risk infants.

A number of women with breast cancer believed they were suffering injury because radiotherapy had been given negligently. In March 1995, their solicitors were permitted by the High Court, to select 10 cases in order to further a group action. In the legal exchanges which followed, the principal issues put forward by the plaintiffs went through a number of modifications until finally, in December 1997, they were abandoned. Two cases came to trial and after a hearing of 21 days, the Judge found no negligence. Clinical oncologists should be aware of the course of the litigation and consider the lessons to be learned.

This study investigated the comparability between three "amazingly" short forms of the WAIS-R (a dyad, triad, and tetrad) suggested by Kaufman, Ishikuma, and Kaufman-Packer (1991) and the complete battery among a sample of 114 educable mentally handicapped adolescents. Results indicate that the short forms are highly correlated with the complete battery Full Scale IQs, and all three short forms yielded scores, on average, within 2 points of the complete battery. Analyses at an individual level revealed that more than 90% of the sample fell within 3 SEM (9 points) of the FSIQ for all three short forms. Overall results are consistent with previous studies and support the use of these "amazingly" short forms.

This study investigated the comparability of item-reduction and subtest-reduction short forms of the Stanford-Binet Intelligence Scale: Fourth Edition (SB:IV) with the complete battery in a sample of college students. All item-reduction SASs were not significantly different from the full battery SASs. Correlations for corresponding SASs and subtests between the complete and short form were highly significant, and analyses of the short-form profile supported the interpretation of individual subtests. The subtest-reduction short-form SASs were significantly lower than both the item-reduction short form and the full battery. Thus, an item-reduction short form proved to be a more comparable estimate of the full battery composite than the subtest-reduction short form.