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INTRODUCTION: Adolescent females with developmental delays (DDs) experience unique physical and emotional challenges related to menstruation. Providers often recommend hormonal medication for menstrual management. The objective of our study was to describe the utilization and safety of the levonorgestrel-releasing intrauterine system (LNG-IUS) in adolescents with DDs. METHODS: We utilized the Pediatric Health Information System to identify females aged 10-25 with DDs who underwent an LNG-IUS insertion between 2011 and 2020. Using a gynecologic procedure and diagnosis codes, we assessed indications for and complications of LNG-IUS use. We also evaluated early LNG-IUS removal. RESULTS: One thousand five hundred and sixty female patients with DDs underwent LNG-IUS insertion. LNG-IUS insertion under anesthesia was most commonly performed in patients with autism and Down syndrome, and unspecified menstrual issues were documented for 40% of the cohort. Perforation was observed in 11 patients (1%), and mechanical complications (malpositioned IUS or lost threads) were observed in 23 patients (1%). DISCUSSION: This is the largest analysis of LNG-IUS use in patients with DDs to our knowledge and shows the utilization of LNG-IUS in patients with DDs. We provide descriptive information that providers can use to accurately advise their patients with DDs on the risks and benefits of LNG-IUS use for menstrual management.

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For illustrative purposes, in this article we use "Johansen Plots" as a graphical way of simultaneously visualizing the inter-connected variables that compose the convective steps of the gas transport cascade. These plots are used to reflect on some of the physiological characteristics seen in five species of birds, four of which sojourn to, or are native to, high altitudes (the barnacle goose, bar-headed goose, Andean goose, speckled teal and ruddy duck). These species were chosen to emphasize the diversity of responses to hypoxia that can exist within a single family. This diversity likely arose for many possible reasons, including local adaptation to hypoxia, differences in flight or diving abilities, or as a result of other phylogenetically-based differences across waterfowl in physiology, behaviour, and/or life style.

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Documenting patterns of host specificity in parasites relies on the adequate definition of parasite species. In many cases, parasites have simplified morphology, making species delimitation based on traditional morphological characters difficult. Molecular data can help in assessing whether widespread parasites harbour cryptic species and, alternatively, in guiding further taxonomic revision in cases in which there is morphological variation. The duck louse genus Anaticola (Phthiraptera: Philopteridae), based on current taxonomy, contains both host-specific and widespread species. Mitochondrial and nuclear DNA sequences of samples from this genus were used to document patterns of host specificity. The comparison of these patterns with morphological variations in Anaticola revealed a general correspondence between the groups identified by DNA sequences and morphology, respectively. These results suggest that a more thorough taxonomic review of this genus is needed. In general, the groups identified on the basis of molecular data were associated with particular groups of waterfowl (e.g. dabbling ducks, sea ducks, geese) or specific biogeographic regions (e.g. North America, South America, Australia, Eurasia).

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Andean uplift played a key role in Neotropical bird diversification, yet past dispersal and genetic adaptation to high-altitude environments remain little understood. Here we use multilocus population genetics to study population history and historical demographic processes in the ruddy duck (Oxyura jamaicensis), a stiff-tailed diving duck comprising three subspecies distributed from Canada to Tierra del Fuego and inhabiting wetlands from sea level to 4500 m in the Andes. We sequenced the mitochondrial DNA, four autosomal introns and three haemoglobin genes (α(A), α(D), ß(A)) and used isolation-with-migration (IM) models to study gene flow between North America and South America, and between the tropical and southern Andes. Our analyses indicated that ruddy ducks dispersed first from North America to the tropical Andes, then from the tropical Andes to the southern Andes. While no nonsynonymous substitutions were found in either α globin gene, three amino acid substitutions were observed in the ß(A) globin. Based on phylogenetic reconstruction and power analysis, the first ß(A) substitution, found in all Andean individuals, was acquired when ruddy ducks dispersed from low altitude in North America to high altitude in the tropical Andes, whereas the two additional substitutions occurred more recently, when ruddy ducks dispersed from high altitude in the tropical Andes to low altitude in the southern Andes. This stepwise colonization pattern accompanied by polarized ß(A) globin amino acid replacements suggest that ruddy ducks first acclimatized or adapted to the Andean highlands and then again to the lowlands. In addition, ruddy ducks colonized the Andean highlands via a less common route as compared to other waterbird species that colonized the Andes northwards from the southern cone of South America.

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The aim of this study was to establish relationships between chemical and physical parameters of wheat with performance and digestibilities of feed components in broiler chickens fed on wheat-based diets. Ninety-four wheat samples were selected for inclusion in four bird trials. Birds were housed in individual wire metabolism cages from 7 to 28 d and offered water and feed ad libitum. Dry matter intake (DMI), liveweight gain (LWG) and gain:feed were measured weekly. A balance collection was carried out from 14 to 21 d for determination of apparent metabolizable energy (AME), ME:gain, dry matter retention, oil and neutral detergent fibre (NDF) digestibility. At 28 d the birds were humanely killed, the contents of the jejunum removed for determination of in vivo viscosity and the contents of the ileum removed for determination of ileal dry matter, starch and protein digestibility. When wheat parameters were correlated with bird performance data, it was found that specific weight was not significantly (p>0.05) related to bird performance. Bird DMI, LWG and gain:feed were best correlated (p<0.05) with the rate of starch digestion, although the coefficients of correlation (r) were still low (0.246 to 0.523). A negative relationship (p<0.01) between AME and total (r = -0.432) and soluble (r = -0.304) non starch polysaccharide (NSP) was observed in this study. Thousand grain weight (TG) was positively correlated with DMI (r = 0.299), LWG (r = 0.343) and gain:feed (r = 0.371). When establishing multiple regression relationships, correlation coefficients greater than 0.8 were achieved for DMI, LWG, gain:feed and ileal crude protein digestibility. However, the economics involved in determining the parameters involved in the regressions make the process impractical.

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The aim of this study was to examine the effect of variety and growing conditions of wheat on broiler performance and nutrient digestibility. One hundred and sixty-four wheat samples, collected from a wide range of different sources, locations, varieties and years, were analyzed for a range of chemical and physical parameters. Chemical and physical parameters measured included specific weight, thousand grain weight (TG), in vitro viscosity, gross energy, N, NDF, starch, total and soluble non-starch polysaccharides (NSP), lysine, threonine, amylose, hardness, rate of starch digestion and protein profiles. Ninety-four of the wheat samples were selected for inclusion in four bird trials. Birds were housed in individual wire metabolizm cages from 7 to 28 d and offered water and feed ad libitum. Dry matter intake (DMI), live weight gain (LWG) and gain:feed were determined weekly. A balance collection was carried out from 14 to 21 d for determination of apparent metabolizable energy (AME), ME:gain, DM retention, oil and NDF digestibility. At 28 d the birds were sacrificed, the contents of the jejunum removed for determination of in vivo viscosity and the contents of the ileum removed for determination of ileal DM, starch and protein digestibility. The wheat samples used in the study had wide-ranging chemical and physical parameters, leading to bird DMI, LWG, gain:feed, ME:GE, AME content and ileal starch and protein digestibility being significantly (p<0.05) affected by wheat sample. A high level of N fertilizer application to the English and NI wheat samples tended to benefit bird performance, with increases of up to 3.4, 7.2 and 3.8% in DMI, LWG and gain:feed, respectively. Fungicide application also appeared to have a positive effect on bird performance, with fungicide treated (+F) wheat increasing bird DMI, LWG and gain:feed by 6.6, 9.3 and 2.7%, over the non-fungicide treated (-F) wheats. An increase (p<0.1) of 9.3% in gain:feed was also observed at the low seed rate of 40 compared to 640 seeds/m(2). It was concluded that the type of wheat sample and environmental growing conditions significantly affects bird performance when fed wheat-based diets.

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Two trials were conducted to investigate the effect of decreasing the crude protein (CP) content of diets for finishing pigs containing two levels of available lysine on nutrient digestibility, nitrogen (N) balance and production performance. Ten finishing diets containing five levels of CP (on average 144, 155, 168, 182 and 193 g/kg fresh basis) and two levels of available lysine (6.9 and 8.2 g/kg fresh basis) were formulated. The diets were offered to pigs on a performance trial (n = 800 Large White (LW)×Landrace (LR) pigs) from 10 wk of age until finish at 21 wks+5 d of age. Average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated. In addition, a digestibility/N balance trial was conducted using pigs (n = 80 LW×LR) housed in metabolism crates. Digestibility of dry matter (DM), CP, oil, fibre and energy was determined. N balance values were determined through analysis of N content of urine and faeces ('as determined'). N balance values were also calculated using ADG values and assuming that 16% of growth is protein deposition ("as calculated"). Pig performance was poor between 10 and 13 wk of age which indicated that the dietary treatments were nutritionally inadequate for pigs less than 40 kg. There was a significant (p<0.01) quadratic effect of increasing CP level on feed intake, ADG and FCR from 10 to 13 wk which indicated that the lower CP levels did not supply adequate levels of essential or non-essential amino acids. There was no effect of increasing available lysine level throughout the early period, which in conjunction with the response in older pigs, suggested that both 8.2 and 6.9 g/kg available lysine were insufficient to drive optimum growth. There was a positive response (p<0.05) to increasing available lysine level from 13 wk to finish which indicated that 6.9 g/kg available lysine was not adequate for finishing pigs. Energy digestibility decreased with decreasing CP level of diets containing 6.9 g/kg available lysine which may be attributed to the higher fibre content of the lower CP diets. Nitrogen excretion (g/d) was lowered when dietary CP was reduced regardless of whether the values were determined through balance or calculated using ADG. Calculated N excretion decreased linearly (p<0.001) and quadratically (p<0.001) with decreasing dietary CP content. When the N balance figures calculated in this study were compared with those quoted in the Northern Ireland and English Nitrates Directive Action Programmes, N excretion was less per pig (wean to finish) offered a 169 g/kg CP, 8.2 g/kg available lysine diet (2.39 kg vs 3.41 kg (Northern Ireland) and 2.93 kg (England)).

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Theory predicts that parallel evolution should be common when the number of beneficial mutations is limited by selective constraints on protein structure. However, confirmation is scarce in natural populations. Here we studied the major haemoglobin genes of eight Andean duck lineages and compared them to 115 other waterfowl species, including the bar-headed goose (Anser indicus) and Abyssinian blue-winged goose (Cyanochen cyanopterus), two additional species living at high altitude. One to five amino acid replacements were significantly overrepresented or derived in each highland population, and parallel substitutions were more common than in simulated sequences evolved under a neutral model. Two substitutions evolved in parallel in the alpha A subunit of two (Ala-alpha 8) and five (Thr-alpha 77) taxa, and five identical beta A subunit substitutions were observed in two (Ser-beta 4, Glu-beta 94, Met-beta 133) or three (Ser-beta 13, Ser-beta 116) taxa. Substitutions at adjacent sites within the same functional protein region were also observed. Five such replacements were in exterior, solvent-accessible positions on the A helix and AB corner of the alpha A subunit. Five others were in close proximity to inositolpentaphosphate binding sites, and two pairs of independent replacements occurred at two different alpha(1)beta(1) intersubunit contacts. More than half of the substitutions in highland lineages resulted in the acquisition of serine or threonine (18 gains vs. 2 losses), both of which possess a hydroxyl group that can hydrogen bond to a variety of polar substrates. The patterns of parallel evolution observed in these waterfowl suggest that adaptation to high-altitude hypoxia has resulted from selection on unique but overlapping sets of one to five amino acid substitutions in each lineage.

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1. The aims of this study were to investigate the potential of near infrared reflectance spectroscopy (NIRS) to predict the chemical and physical characteristics of wheat and also to predict the nutritive value of wheat for broiler chickens. 2. A total of 164 wheat samples, collected from a wide range of different sources (England, Northern Ireland and Canada), varieties and years, were used in this study. 3. Chemical and physical parameters measured included specific weight, thousand grain weight, in vitro viscosity, gross energy, nitrogen, neutral detergent fibre (NDF), starch, total and soluble non-starch polysaccharides (NSP), lysine, threonine, amylose, hardness, rate of starch digestion and protein profiles. 4. A total of 94 wheat samples were selected for inclusion in three bird trials and included at 650 g/kg in a typical UK starter/grower diet. Birds were housed in individual wire metabolism cages from 7 to 28 d and offered water and food ad libitum. Dry matter intake (DMI), live weight gain (LWG) and gain:feed ratio were measured weekly. A balance collection was carried out from d 14 to 21 for determination of apparent metabolisable energy (AME), ME:gain and dry matter retention. At 28 d the birds were humanely killed, the contents of the jejunum removed for determination of in vivo viscosity and the contents of the ileum removed for determination of ileal dry matter, starch and protein digestibility. 5. The wheat samples were scanned as whole and milled wheat, both dried and undried and NIRS calibrations, first excluding and then including the Canadian wheat samples, were developed. 6. NIRS calibrations for milled wheat samples may be useful for determining specific weight (R(cv)(2) = 0.75, for milled wheat dried), nitrogen (R(cv)(2) = 0.983 for milled and dried) and rate of starch digestion (R(cv)(2) = 0.791 for milled, dried and undried). 7. NIRS calibrations for whole wheat samples (undried) may be useful for determining wheat nutritive value, with good predictions for live weight gain (R(cv)(2) = 0.817) and feed conversion efficiency (R(cv)(2) = 0.825). 8. Inclusion of the Canadian wheat samples in the NIRS analysis provided additional robust calibrations for gross energy (R(cv)(2) = 0.86, dried and milled) and starch content (R(cv)(2) = 0.79, undried and milled). 9. This study shows that NIR is a useful tool in the accurate and rapid determination of wheat chemical parameters and nutritive value and could be extremely beneficial to both the poultry and wheat industry. 10. Further extension of the dataset would be recommended to further validate these findings.

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1. A study of the relationship between specific weight (SW) and nutritive value of wheat in diets offered to broilers up to 4 weeks of age was carried out using 10 varieties of wheat grown at three different locations; this gave rise to a range of specific weights from 59 to 76 kg/hl. 2. Because five varieties contained the 1B1R translocation and 5 did not, this allowed the effects of 1B1R on the performance of birds given high concentrations of dietary wheat to be further investigated. 3. The diets, which contained wheat at 744 g/kg with casein (142 g/kg) as the sole protein supplement, were heat-treated and pelleted. They were fed ad libitum to male, Ross broiler chicks from 7 to 28 d, in individual cages in a controlled environment room. 4. A 7 d excreta collection was made from 14 to 21 d for determination of apparent metabolisable energy (AME) content and wheat AME was calculated from the diet values. A separate determination of true metabolisable energy (TME) was undertaken using the method of McNab and Blair (British Poultry Science, 29: 697-707, 1988). 5. Wheat samples were analysed for proximate constituents, starch, total and soluble non-starch polysaccharides (NSP), amino acid content and gross energy and specific weight, thousand grain weight and in vitro viscosity were recorded. They were also subjected to near infrared reflectance spectroscopy (NIRS) with a view to establishing relationships with chemical constituents and performance parameters. 6. At 28 d the birds were humanely killed and in vivo viscosity was determined on the jejunal digesta supernatant. 7. There was quite a narrow range of crude protein content (N x 5.83) across the 30 wheat samples, the means for the three locations (Crossnacreevy, Downpatrick and Limavady, respectively) being 112, 121 and 122 g/kg. Starch contents of individual samples ranged from 604 to 679 g/kg, total NSP from 92.1 to 122.6 g/kg, soluble NSP from 17.6 to 32.6 g/kg and in vitro viscosity from 10.6 to 26.3 cps. 8. There were no significant varietal effects for dry matter intake (DMI), live weight gain (LWG) or gain:feed ratio. Apparent metabolisability of energy (ME:GE) for the diets ranged from 0.738 (Hussar) to 0.778 (Harrier) the effect being significant (P < 0.05) and there was a significant (P < 0.001) relationship (r(2) = 0.46) between ME:GE and gain:feed ratios. Calculated wheat AME for individual varieties ranged from 14.1 to 15.0 MJ/kg DM (P > 0.05). TME values ranged from 16.3 to 16.6 MJ/kg DM (NS). 9. In vivo viscosity ranged from 12.3 (Ritmo) to 23.7 cps (Hussar), the varietal effects being significant (P < 0.001). Viscosity was significantly higher for the 1B1R varieties than for the non-1B1R (22.7 vs 16.3 cps) but there were no significant effects on mean DM intake, LWG, gain:feed, ME:GE, calculated wheat AME, ME:gain (MJ AME per kg gain) or TME. 10. Wheat AME was negatively correlated (P < 0.05) with total NSP (slope -0.035) but was significantly affected by variety, constants ranging from 16.74 to 17.79. For wheat TME there were significant variety*total NSP interactions with slopes ranging from 0.29 to -0.07. There was no significant relationship between wheat AME and soluble NSP and there were significant variety*soluble NSP interactions for TME with slopes ranging from 0.09 to -0.14. 11. Despite the relatively wide range of in vitro viscosity there was no significant correlation of either calculated wheat AME or wheat TME with in vitro viscosity. For TME there were significant variety*viscosity interactions with slopes ranging from 0.21 to -0.13 (P < 0.001). There was also no significant correlation between soluble NSP and in vivo viscosity. 12. AME values for the NIRS calibration set varied from 13.7 to 15.6 MJ/kg and averaged 14.6 MJ/kg, whereas for the validation set, the values ranged from 14.0 to 16.1 MJ/kg with the mean value being 14.7 MJ/kg. The best correlation coefficient (r(2)) of 0.90 was obtained when the calibration sample set was subjected to SMLR using the second-order derivatised data. However, moving to validation, the outcome was extremely poor with 1-VR values being 0.12 and 0.09, respectively, for the external validation and an internal validation subset. 13. In summary, none of the production characteristics showed a good correlation with specific weight. Using the linear estimates for wheat AME and TME the effect of a 10 kg/hl change in SW equates to a 3 or 1.4% change, respectively. The estimate for AME is likely to be a worst-case value due to the high inclusion level of wheat. The range of calculated wheat AME (approximately 1 MJ) across the 30 wheat samples is similar to that seen in previous studies for wheat grown in Northern Ireland and much lower than in some other studies. 14. None of the other parameters examined gave any better relationship with nutritive value (assessed as AME or TME) than SW. This is a disappointing outcome, particularly in view of some previous studies which suggested that in vitro viscosity provides a good prediction of nutritive value.

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1. The objectives of this experiment were to investigate the effects of different xylanases, alone or in combination with different organic acid and oligosaccharide sources, on bird performance, gut microflora and ileal histology. 2. Birds were given a diet based on a commercial formulation, which was split into 8 batches. Batch 1 contained the antibiotic growth promoter Avilamycin and acted as the positive control. To batch 2 the enzyme Allzyme PT was added and to batch 3 Allzyme PT was added with the organic acid and oligosaccharide mixture Avimos. To batch 4, Allzyme PT was added with the oligosaccharide mixture Biomos. To batch 5, yeast extract 2012 was added with the organic acid mixture Gustor and the enzyme xylanase XP20. To batch 6, yeast extract 2012 and feed acidifier Gustor were added as before, with the enzyme Avizyme 1300. Batches 7 and 8 both acted as negative experimental controls, with no added growth promoters. 3. A total of 64 birds were housed in individual wire cages in each of three consecutive experimental replicates (24 birds/treatment). Birds were fed ad libitum from 7 to 28 d and a 7-d excreta collection was carried out to determine apparent metabolisable energy (AME) content. 4. At 28 d, the birds were killed and viscosity of jejunal digesta supernatant and gizzard weight were determined. Samples were taken from the crop, ileum and caecum and analysed for viable presumptive lactic acid bacteria and coliforms. The overall microbial flora was determined using denaturing gradient gel electrophoresis of 16S ribosomal DNA followed by DNA sequence analysis in order to assign amplicons to a bacterial species. Ileal sections were also collected for histological analysis. 5. Total live weight gain (12%) and gain:feed (9%) were significantly improved for all diets containing additives, compared to the negative control diets. All diets containing xylanases gave significantly lower in vivo viscosity values than the positive and negative controls. Diet treatment significantly affected viable coliform numbers in the ileum and also viable lactobacilli in the ileum and caecum. A substantial proportion of the bacteria present in the GI tract (40%) belong to unknown species. No effects of diet treatment on histological measurements were observed in this study. 6. All the additive combinations studied were at least as effective as the antibiotic growth promoter and the results for Allzyme PT suggest that xylanase alone is as effective as any of the combinations studied.

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1. The objectives of this experiment were to compare the effects of different yeast products, with different nucleotide contents and inclusion rates, on broiler performance and to compare the effects to those observed with an antibiotic growth promoter. 2. Two experiments were carried out over two time replicates, one in individual wire cages and one in group pens. 3. Birds were given a diet based on a commercial formulation, which was split into 7 batches. One batch (C) contained no growth promoter and acted as a negative control, another (AV) contained the antibiotic growth promoter Avilomycin (5 g/tonne) and acted as the positive control. The other batches contained yeast extract 2012 at 100 g/tonne (Y21), yeast extract 2012 at 500 g/tonne (Y25), standard yeast 18 at 100 g/tonne (Y81), standard yeast 18 enriched in nucleotides at 100 g/tonne (Y8N1) and standard yeast 18 enriched in nucleotides at 500 g/tonne (Y8N5). 4. In the penned experiment, 280 Cobb broiler chicks (40 birds/treatment) were randomised to diet and pen position on day of hatch. Birds were fed ad libitum until slaughter at 28 d. Bird performance was monitored during the experimental period. 5. In the individual cage experiment, 63 Cobb broiler chicks (9 birds/treatment) were taken from the pens at 7 d of age and randomised to diet and cage position. Birds were fed ad libitum from d 7 to d 28. A 7-d excreta collection was carried out to determine apparent metabolisable energy (AME) content and nutrient digestibility between d 14 and d 21. Bird intake and weight were monitored weekly during the experimental period. At 28 d the birds were killed and viscosity of jejunal digesta supernatant was determined. 6. In the penned experiment, diet had no significant effect on dry matter intake (DMI), live weight gain (LWG) or gain:feed values during any individual week of the experiment or for the entire experimental period. In the caged experiment, DMI was numerically highest for birds fed Y25 diet over the entire experimental period, however, this only reached significance in the second week. LWG, gain:feed, viscosity of jejunal contents and gizzard weight were not significantly affected by dietary treatment. 7. Diet AV had a significantly higher AME content than diets Y25, Y81, Y8N1 or Y8N5. Also, oil and neutral detergent fibre (NDF) digestibility coefficients were significantly affected by diet treatment.

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The study was designed to provide quantifiable information on both within- and between-herd variation in pig growth rate from birth to slaughter and to examine how this was influenced by moving pigs at a common age to a common environment. Five litters were selected from each of eight pig herds in Northern Ireland with varying growth performance. All eight herds were offered the same nutritional regime. Five pigs (three boars and two gilts) were selected from each litter. In each herd, 22 pigs (12 boars and 10 gilts) were weighed individually, every 4 weeks, from 4 to 20 weeks of age. At 4 weeks of age (weaning) three non-sibling boars were taken from each herd and brought to a common environment where they received medication, were housed individually from 6 weeks of age and offered the same dietary regime. They were weighed and feed intakes were recorded twice weekly. A growth rate difference of 61 g/day (P < 0.001), 112 g/day (P < 0.01) and 170 g/day (P < 0.001) was observed on farm, between the top and bottom quartile of herds during 4 to 8, 8 to 12 and 12 to 20 weeks of age, respectively. This difference in growth rate equated to an average difference in cost of production of ¢13/kg carcass on a birth to bacon unit. When pigs from the different herds were housed in the common environment, large variation in growth performance (143 g/day (P < 0.01) and 243 g/day (P < 0.001) for 8 to 12 and 12 to 20 weeks, respectively) was also observed between the top and bottom quartile of herds. Although feed efficiency was similar, a significant feed intake difference of 329 g/day (P < 0.01) and 655 g/day (P < 0.001) between 8 to 12 and 12 to 20 weeks of age was observed. The variation in growth rate between pigs whether managed on farm or in the common environment was similar (variation in days to 100 kg on farm and in the common environment was 18 and 19 days, respectively). When housed in the common environment, although the top and bottom quartile of pigs converted feed equally efficiently, pigs in the top quartile had significantly higher feed intakes suggesting greater appetites. It is difficult to assess the extent to which these differences can be attributed to genetic effects or pre-weaning environment, and how much the effects of management, disease or genetics contributed to the variation between and within herds.

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1. This study used 4 wheat cultivars (Brigadier, Chaucer, Consort, Reaper) from three locations (Crossnacreevy, C; Downpatrick, D; Limavady, L), which had given rise to differences in wheat specific weight (SW), to examine the relationships between apparent metabolisable energy (AME) concentration, broiler performance and wheat SW. 2. The diets contained (g/kg): wheat 744, casein 142, blended vegetable fat 50, dicalcium phosphate 22, potassium bicarbonate 10.8, sodium bicarbonate 7.5, arginine 5, methionine 2, binder 8, trace minerals/vitamins 7.2, titanium dioxide 1.5. The diets were heat-treated (80 degrees C for 2 min) prior to pelleting (3 mm die). 3. SW ranged from 63 to 77 kg/hectolitre (hl), averaging 66, 69 and 76 kg/hl at D, C and L, respectively. In vitro viscosity of the wheat samples ranged from 5.2 to 17.5 cps and thousand grain weight (TGW) from 33.4 to 47.3 g. Mean TGW was similar at C and D (38.7, 37.0 g) but higher at L (43.1 g). In vitro viscosity was similar at C and L (11.2, 10.2 cps) but somewhat higher at D (14.4 cps). Crude protein (6.25 N) ranged from 116 to 147 g/kg and tended to be higher at D. Starch, which ranged from 612 to 656 g/kg, was least at D (617 g/kg) and greatest at L (641 g/kg). 4. Crude protein, crude fibre and total non-starch polysaccharide (NSP) were negatively correlated with SW, the R2 being respectively 0.38 (P<0.05), 0.16 (NS) and 0.45 (P<0.05). TGW and starch concentration were positively correlated with SW (R2=0.70, 0.44, respectively). There was a weak (NS) negative relationship (R2=0.19) between in vitro viscosity and SW. For both TGW and in vitro viscosity, correlations improved when variety was taken into account (R2=0.95, 0.92, respectively). 5. There were no significant effects of variety on dry matter (DM) intake or live weight gain (LWG). Gain: food was significantly higher (P<0.05) for Consort than for the other three varieties and the metabolisable energy ratio (ME:GE) just failed to attain significance (P=0.062). Calculated wheat AME (MJ/kg DM) was significantly (P<0.05) higher for Consort than for the other three wheats. There was a good correlation (R2=0.49) for the total data set between gain:food and ME:GE. In vivo viscosity varied from 13.6 to 28.6 cps for individual treatments and was significantly affected by variety (P<0001). 6. Although there were no significant differences in DM intake or LWG due to site the values for L (SW 76) were 6 and 5% lower, respectively, than for D (SW 66). Gain:food was lower (P<0.05) for C (SW 69) than for D. ME:GE, wheat AME and ME:gain were not significantly different between sites. 7. There was a weak (R2=0.18) positive relationship between ME:GE and SW corresponding to a 2.5% increase in energy value for a 10 kg/hl increase in SW and no relationship between gain:food and SW. When variety was taken into the regression the slope was similar but R2 increased to 0.82. 8. ME:GE and wheat AME concentration were negatively correlated with wheat in vitro viscosity (R2=0.64, 0.55, respectively). 9. It was concluded that in vitro viscosity appears to provide a better basis than SW for prediction of the nutritive value of wheats of unknown variety. If the variety is known then SW could be used to predict energy value. However, the effect of quite a large change in SW (10 kg/hl) was relatively small.

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Use of the Australian Bureau of Statistics' SEIFA scores has almost become an automatic practice in area-based research on socio-economic status (SES) correlates of health inequalities in Australia in recent years. This article questions the wisdom of this emerging heavy, often singular, reliance on the SEIFA indexes for representing a real socio-economic condition. It is argued that improvements in our understanding of the social and economic processes that produce health inequalities will not occur unless we move beyond SEIFA's broad brush. Data for New England Area Health local government areas are used to support the argument.

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1. The study used a 3 x 3 factorial design to evaluate the effects of 3 additives (none; vitamin C [250 mg/kg]; copper sulphate [250 mg/kg]) and 3 enzyme additions (none; Avizyme 1300 [Finnfeeds Ltd, 1 g/kg in food]; Avizyme 1310 [liquid spray, post-pelleting, 0.5 g/kg]). All experimental diets were mixed, heat-conditioned (80 degrees C for 2 min) and pelleted. Copper sulphate (diets NCu; DCu; LCu) and Avizyme 1300 (diets DN; DC; DCu) were added during mixing. Vitamin C was sprayed at 10 ml per kg (diets NC; DC; LC) and the liquid enzyme was diluted 20-fold and sprayed at the same rate (diets LN; LC; LCu), post-pelleting. 2. Additive or enzyme addition did not significantly affect DM intake or liveweight gain (LWG). Enzyme addition improved gain:food (P=0.014), AME:GE (P<0.001), ileal apparent digestibility of DM (P=0.008) and starch (P<0.001), faecal apparent digestibility of starch, crude fat and NDF (P=0.008; <0.001; <0.001 respectively) and reduced in vivo viscosity (P<0.001). 3. Copper sulphate addition depressed gain:food (P=0.047), AME:GE (P=0.002), ileal apparent digestibility of starch (P<0.001) and faecal apparent digestibility of starch (P=0.003) and crude fat (P<0.001) due to a negative additive x enzyme interaction when copper sulphate and dry enzyme were included together. 4. Vitamin C decreased in vivo viscosity by 20% but failed to have any effect on performance. Both enzyme forms gave similar improvements in performance in the absence of copper sulphate.

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Surprisingly few birds have penises, but among those that do, the Argentine lake duck (Oxyura vittata) tops the bill - the penis of this small stifftail duck from South America is shaped like a corkscrew and, at almost half a metre long, is the largest of any bird measured so far. Factors responsible for the evolution of this remarkable organ could include runaway selection, whereby drakes with longer penises gain dominance and copulate with more females, or preference by females for drakes with longer and more decorated penises.

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