Employment, Education, and Income for Canadians with Developmental Disability: Analysis from the 2017 Canadian Survey on Disability.

This study assessed needs and outcomes for people with developmental disability (DD) to understand the socioeconomic status of this group prior to implementation of the Accessible Canada Act in June 2019. The 2017 Canadian Survey on Disability (CSD) was used to analyze data for a sample of individuals with self-reported disability. Data related to employment, education, income, housing, caregivers, and use of government benefits is reported. Compared to the general Canadian public, persons with DD are less likely to: finish high-school or post-secondary education; participate in the labor force or be employed; and earn on average less/year in total income. To align with recent accessibility legislation, significant progress is needed to address disparities for people with DD.

Why children from the same family are so different from one another : A Darwinian note.

The well-established finding that siblings growing up in the same family turn out to be very different from one another has puzzled psychologists and behavior geneticists alike. In this theoretical note we describe the possible ontogeny and phylogeny of a sibling differentiation mechanism. We suggest that sibling competition for parental investment results in sibling differentiation on a number of characteristics, producing different developmental trajectories within families. Variations in developmental trajectories within families may have had fitness advantages in ancestral environments because(a) sibling competition for extrafamilial resources would be reduced and(b) these variations would be suited to environments containing a variety of niches or to changing environments. Predictions derived from this model and an example of an application to attachment theory are presented.

Kindergarten predictors of boys' stable behavior problems at the end of elementary school.

This study predicted stable social maladjustments of ages 10, 11, and 12 from teacher behavioral ratings in kindergarten and a measure of family demographics. Kindergarten teachers rated 1,034 boys on hyperactivity, aggression, inattention, anxiety-withdrawal, and prosocial behavior. Sociodemographic information was collected from the parents. At ages 10, 11, and 12, teacher, parent, peer, and self-report behavior ratings were collected on 743 boys. School achievement was documented from school records. Boys whose average scores on each of the five behavioral ratings across ages 10, 11, and 12 were above the 90th percentile according to at least two informants were defined as having stable behavioral problems. From teacher ratings collected in kindergarten and family demographics, logistic regression analyses predicted stable social maladjustment. For each negative outcome there was a unique set of predictors. The results are discussed with reference to the early identification of children who are at risk.

Monensin and ammoniation or urea supplementation of bermudagrass hay diets for steers.

One growth trial using crossbred beef steers (297 +/- 2 kg, Exp. 1) and one metabolism trial using Holstein steers (405 +/- 14 kg, Exp. 2) were conducted to evaluate effects of ammoniation (3% of hay DM, added as anhydrous NH3) vs urea supplementation with or without monensin supplementation of mature 'Alicia' bermudagrass hay-based diets for steers. Ammoniation (P < .05), but not urea (P = .26) or monensin (P = .70) supplementation, increased ADG in Exp. 1. In Exp. 2 ammoniation increased hay DMI (P < .05), but urea (P = .88) or monensin (P = .16) had no effect. Supplementation with either monensin (P < .05) or urea (P < .05) decreased ruminal total VFA concentrations. Monensin also decreased the ruminal acetate:propionate ratio (P < .001) and increased ruminal pH (P < .05). Addition of urea to the concentrate supplement decreased the rate of concentrate intake. Both the rate (P < .05) and the potential extent (P < .001) of ruminal forage in situ DM and NDF disappearance were increased by ammonia treatment. Dietary interactions (P < .10) were detected between monensin and ammoniation for rate and potential extent of in situ NDF disappearance and between monensin and urea supplementation (P < .05) for ruminal total free amino acid concentrations. Decreased concentrations of VFA and lower forage digestibilities observed with monensin supplementation in Exp. 2 may explain the failure of monensin to affect ADG in Exp. 1.

Ruminal distribution of zinc in steers fed a polysaccharide-zinc complex or zinc oxide.

Six Holstein steers (initial BW 335 kg) were used in a replicated 3 x 3 Latin square design to study the distribution of Zn in ruminal contents from a conventional Zn source (ZnO) or Zn sequestered to a polysaccharide (PC-Zn). Treatments consisted of a basal diet (no Zn supplementation) and the basal diet supplemented with Zn from either PC-Zn or ZnO. Steers were provided with 208, 920, or 896 mg of Zn/d from basal, PC-Zn, or ZnO, respectively. On collection day, steers were dosed with 800 mg of Zn from each Zn supplement and whole ruminal contents (WRC) were sampled at 1, 2, 4, 6, and 8 h postdosing. The cell-free (soluble) Zn concentrations in steers fed the PC-Zn or ZnO supplements decreased (P < .05) rapidly after dosing. Mean Zn concentrations of the cell-free fraction were considerably lower than either microbial or particle fractions of WRC. Compared with ZnO, the PC-Zn source resulted in higher (P < .05) cell-free Zn at 1 and 2 h after dosing and higher (P < .05) Zn concentrations (micrograms/gram of DM) in the fluid- and particle-associated microbial and particle fractions. Compared with basal, fluid-associated microbial DM concentration tended to be higher (P < .10) at 6 and 8 h with PC-Zn and ZnO. Results indicate a rapid disappearance of Zn from the soluble fraction and a high concentration of Zn in the DM of the microbial and particle fractions of WRC. Furthermore, PC-Zn resulted in higher levels of Zn in all fractions of WRC, and Zn supplementation tended to increase microbial DM production at later sampling times.

Quantity and characteristics of microorganisms associated with ruminal fluid or particles.

An experiment was conducted to 1) determine quantity of microbial CP and DM associated with undigested feed particles, 2) quantify the amount of microorganisms removed from ruminally incubated forages and 3) compare forage disappearances (D) corrected for microbial contamination, using diaminopimelic acid (DAPA) ratios obtained from particle-associated or fluid-associated microorganisms. Samples of alfalfa hay, bermudagrass hay and orchardgrass hay placed in dacron bags were incubated via ruminal cannula for 6 and 12 h. Whole ruminal contents (WRC) were sampled at the time of bag removal and partitioned into fluid- and particle-associated microorganisms. Particle-associated microorganisms were further divided into loosely-associated (LA) and firmly associated (FA) microorganisms. Percentage microbial CP and DAPA, quantities of OM, CP (mg) and DAPA (micrograms), microbial contamination and microbial contribution to ruminal contents were not affected by time (P greater than .05). The highest concentrations of CP and DAPA were found in fluid and LA, respectively (P less than .01). The total amount (content) of OM, CP and DAPA were highest in FA and lowest in microbes in the fluid fraction. Firmly-associated microorganisms constituted 54.1% of the particle-associated population. Corrected DMD were higher (P less than .01) based on FA than on fluid and LA microbe compositions. Corrected CPD were similar (P greater than .10) between populations except at 6 h, when LA corrected CPD were lower. Theoretically, using FA microorganisms should give the most accurate correction for microbial contamination. However, results indicate that, although the three populations differed in composition, fluid and FA corrected CPD were similar. Corrections based on composition of any of these three populations will yield higher estimates of disappearance compared with uncorrected values.

Effects of mastication and microbial contamination on ruminal in situ forage disappearance.

In an experiment to determine the effects of mastication and microbial contamination on in situ forage disappearance, samples of masticated (M) or nonmasticated alfalfa hay (AH), orchardgrass hay (OGH) and bermudagrass hay (BGH) were incubated in the rumen of two steers for 6, 12, 24, 48 and 96 h. Using diaminopimelic acid as a marker, microbial DM and CP contamination ranged from 10.3 to 22.3% and 46.3 to 95.3% of residual DM and CP, respectively. Percentage contamination was influenced by both time of incubation and forage treatment (P less than .001). Corrected DM and CP disappearances (DMD and CPD) were higher than apparent disappearances (P less than .001). Maximal NDF and ADF disappearances (NDFD and ADFD) obtained at 96 h were 58.2, 52.4; 62.7, 62.3 and 56.7, 52.6% for AH, OGH and BGH, respectively. Lag times (h) for corrected DMD and CPD were shorter (at least P less than .05) than for apparent disappearances, except for corrected CPD of AH. There were no differences (P greater than .10) in lag time of NDFD or ADFD among forages. Rates of disappearance (%/h) of corrected DMD and CPD were faster (at least P less than .01) than for apparent disappearances. The total quantity of microbial CP (mg CP/g DM) associated with residues varied with time depending on forage type (P less than .001). There was a significant relationship between the quantity of microbial CP contamination and the extent of disappearance. Masticated forages followed trends similar to those of nonmasticated forages, but the effect of mastication was not consistent. Results support the need for microbial correction of in situ forage residues.

Effects of breed and wintering diet on heifer postweaning growth and development.

Fifteen spring-born Angus (AN) and 25 Brangus (BN) weanling heifers were used in a 2x5 factorial arrangement of treatments to evaluate the effects of breed and postweaning winter diet on heifer growth and development. Dietary treatments were warm-season perennial grass hay (H), ammoniated H (AH), H plus .68 kg/d cottonseed meal (HP), H plus .45 kg/d cottonseed meal plus 1.37 kg/d ground corn (HPE) and HPE plus 200 mg/d monensin (HPEM). Mean initial weight and age for the 107-d feed trial were 207 kg and 270 d. Brangus had .06 kg greater (P less than .05) ADG than AN during the trial. Although digestible DM intake (DDMI) relative to body weight was greater (P less than .10) for AN than for BN, ADG:DDMI was greater (P less than .05) for BN than for AN. Heifers fed H and AH lost weight, but heifers fed AH had 50% (P less than .05) less daily weight loss than those fed H. Daily gain increased (P less than .05) incrementally in response to sequential supplement additions of cottonseed meal (AH vs HP; -.10 vs .17 kg), ground corn (HP vs HPE; .17 vs .29 kg) and monensin (HPE vs HPEM; .29 vs .39 kg). Hay DM intake relative to body weight and DDMI were increased (P less than .01) by ammoniation. Intake did not differ between HPE and HPEM. Diet affected age at puberty (P less than .05), which decreased with increased dietary components. Weight differences among diet groups following the winter feed trial were largely eliminated prior to breeding. Nevertheless, H- and AH-fed heifers collectively weighed less (P less than .01) prior to breeding than did heifers of supplemented diet groups. Reproductive development tended to be adversely affected by weight loss during the postweaning period.

Metabolism of peptides and amino acids during in vitro protein degradation by mixed rumen organisms.

In vitro inoculum enriched with particle-associated organisms was prepared using rumen contents from a cow fed a 60% forage, 40% concentrate diet. Treatment of in vitro inoculum with cetyltrimethylammonium bromide was used to release intracellular free amino acids from mixed rumen organisms. Addition of 10 mM tosylarginine methyl ester, a competitive inhibitor of trypsin, decreased degradation rate and intracellular free amino acids in incubations containing either casein or serum albumin. Extracellular peptides increased rapidly to a maximum at 60 min in casein incubations but were not different from zero in albumin incubations. Accumulation of intracellular free amino acids was maximal at 60 min in casein and albumin incubations; the concentration observed with albumin was about one-fourth that with casein. Ammonia production from intact casein was slightly greater than that from acid and enzymatically hydrolyzed casein and about 80% greater than that from albumin. Ammonia production and appearance of extracellular free amino acids lagged behind accumulation of intracellular free amino acids. Results suggest that formation and metabolism of extracellular peptides are important in controlling the rate of protein degradation by mixed rumen organisms.

Ammonia-treated alfalfa silage for lactating dairy cows.

Alfalfa was treated (3.3% of forage wet weight) with an aqua-NH3 (14% N) mix prior to ensiling in 2 consecutive yr. In the 1st yr, NH3-treated silage containing 30.5% DM was higher in pH, N, NH3N, acetic acid and butyric acid contents, and lower in amino acids, soluble carbohydrates, and lactic acid than two untreated silages having 32.8 and 47.5% DM. Milk composition and DM intake did not differ among treatments when these silages constituted 50% of the dietary DM and were fed to lactating cows. In situ and in vitro, but not in vivo, digestion of NDF was greater for NH3 silage. Dry matter content of NH3-treated silage in the 2nd yr was 36.1% and that of the two untreated silages was 37.8 and 54.9%. Silage N, NH3N, and acetic acid content were greater in treated silage. However, pH and butyric acid content were similar among treatments and lactic acid was greater for treated silage. Similar to findings in the 1st yr, milk production and DM intake were not different among treatments. Adding NH3 to alfalfa decreased proteolysis; however, when DM was low (30.5%), the buffering effect of NH3 apparently resulted in increased clostridial fermentation. This did not occur when silage DM was increased to 36.1%, presumably due to higher osmotic pressure. Ammonia addition enhanced fiber digestibility but had no effect on milk production.

Effects of breed and wintering diet on growth, puberty and plasma concentrations of growth hormone and insulin-like growth factor 1 in heifers.

Twenty-five Brangus (BR) and 15 Angus (AN) heifers were used to study the effects of breed and wintering diet on average daily gain (ADG), onset of puberty and plasma concentrations of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). Wintering diets (fed for 107 days beginning November 15) consisted of the following: 1) native grass hay (NGH), 2) ammoniated NGH, 3) NGH plus cottonseed meal, 4) Diet 3 plus corn and 5) Diet 4 plus monensin. After wintering, heifers were transferred to ryegrass pasture for 70 days. Mean ADG during the wintering phase were -.20, -.10, .17, .29 and .39 kg for heifers fed Diets 1 through 5, respectively (P less than .01). ADG was greater (P less than .05) for BR than for AN heifers. Plasma concentrations of GH were higher (P less than .05) in heifers fed Diets 1 and 2 than in heifers fed Diets 3, 4 or 5. Plasma concentrations of IGF-1 were lowest in heifers fed Diet 1 and highest in heifers fed Diets 4 and 5. During ryegrass grazing, GH concentrations were similar for all groups. However, concentrations of IGF-1 were higher (P less than .05) in heifers fed Diets 3, 4 and 5 than in heifers fed Diets 1 and 2. Age at puberty (onset of cyclic progesterone concentrations) was greatest in heifers fed Diet 1 and lowest in heifers fed Diet 5. Weight at puberty was not affected (P greater than .10) by wintering diet but was greater (P less than .01) in BR than in AN heifers. Therefore, negative ADG appears to be associated with elevated plasma GH concentrations in heifers, and plasma IGF-1 concentration appears to be a more accurate indication of nutritional status than plasma concentrations of GH.

Excess crude protein for nongravid gilts.

Twenty-five nongravid crossbred gilts (avg initial wt, 126 kg) were placed on either a high (38%) or a low (13%) crude protein (CP) diet and fed either at the rate of 1.82 kg/d or had ad libitum access to feed. In addition, a fifth group was pair-fed the 13% CP diet to the average intake of the gilts fed high CP ad libitum. The experimental period lasted 30 d. Corn-soybean meal diets were used and CP levels were varied by altering the corn:soybean meal ratio. Gain and gain/feed were reduced (P less than .01) in gilts fed 1.82 kg/d compared with the gilts fed ad libitum or pair-fed gilts. Gain (P less than .03) and feed intake (P less than .01) of gilts with ad libitum access to the 13% CP diet were higher than those of gilts with ad libitum access to the 38% CP diet. Gain/feed was not different (P greater than .10) between the two groups, however. Rate of gain and feed efficiency of gilts pair-fed the 13% CP diet were similar (P greater than .10) to those of gilts with ad libitum access to the 38% CP diet. Plasma total free amino acids, NH3 and total protein were not (P greater than .10) affected by treatment. Plasma urea-N and urinary total N, urea-N and orotic acid were increased (P less than .01) in gilts fed the high CP diet regardless of feed intake level. However, urinary NH3 was higher (P less than .01) in gilts fed the low-protein diet. These results indicate that excess dietary CP for nongravid gilts decreases gain and feed intake and has no effect on efficiency of feed utilization, but it increases plasma urea-N and urinary total N, urea-N and orotic acid.

Post-prandial compositional changes of fluid- and particle-associated ruminal microorganisms.

Two ruminally cannulated cows were fed a diet containing 65% alfalfa haylage and 35% concentrate every 12 h. During two collection periods, whole ruminal contents were sampled before feeding, when feed not eaten was removed (1 h after initiation of feeding) and 1, 2, 3, 4, 6, 8, 10 and 12 h after removal. At each sampling, fluid-associated microorganisms were obtained by straining whole ruminal contents through eight layers of cheesecloth. A portion of the particle-associated population was obtained by chilling squeezed particles before seven successive extractions with saline solution. Microbial ash concentrations ranged from 9.9 to 16.6% of dry matter, with differences due to population (P less than .01) and to time after feeding for both fluid- (P less than .05) and particle-associated (P less than .01) microorganisms. Within 1 h after initiation of feeding, N decreased (P less than .05) from a pre-feeding concentration of 9.5% of organic matter to 7.7% for fluid-associated microorganisms, and from 9.2 to 6.7% for particle-associated microorganisms. Both populations did not return to pre-feeding concentrations until 6 h after feed removal. Nucleic acid concentrations decreased (P less than .05) in both populations after feeding, and did not return to pre-feeding concentrations until 6 h for fluid-associated and 4 h for particle-associated microorganisms. Nucleic acid-to-N ratios were higher (P less than .01) in the fluid- than particle-associated organisms.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitation of microorganisms associated with the particulate phase of ruminal ingesta.

Microbial organic matter associated with rumen particulate and fluid phases was quantified using 15N as the microbial marker in two rumen fistulated cows fed a 65% alfalfa haylage diet. During two collection periods, feed was removed 1 h after initiation of feeding, and cows were dosed with (15NH4)2SO4. Whole rumen contents were sampled before feeding and at various times up to 12 h after feeding. Fluid microorganisms were those that passed through eight layers of cheesecloth. Particle-associated microorganisms were obtained by chilling squeezed particles prior to seven successive extractions with saline solution. The amount of microorganisms removed from particles ranged from 32.1 to 59.9% as measured by 15N. Organic matter (mg/mL strained rumen fluid equivalent) of fluid and particle-associated microorganisms was respectively: 10.7 and 47.5; 12.5 and 35.5; 12.2 and 30.1; 10.7 and 26.1; 10.9 and 26.7; and 8.9 and 20.6, at 2, 3, 4, 7, 9 and 11 h after initiation of feeding. These ratios indicated that 70-80% of microbial organic matter in whole rumen contents was associated with the particulate phase and that particle-associated microbial organic matter was greatest soon after feeding. Analysis of 15N in extracted rumen particles indicated that 50-65% of particle nitrogen and 17-27% of particle dry matter was of microbial origin. These results provide evidence that particle-associated microorganisms make up a major proportion of the total microorganisms in ruminal ingesta and that a large proportion of ingesta particle N can be of microbial origin.

Changes in ruminal concentrations of microbial ammonia and amino acids due to monensin and time.

The effect of monensin (33 mg/kg) and no monensin on distribution of ammonia and free amino acids in fluid and particulate phases of ruminal contents was studied. Two Jersey cows and two Angus-Hereford steers, weighing approximately 350 kg and each containing a ruminal cannula were meal fed a 65% concentrate diet for two periods. Feed was available for 30 min; any feed not eaten was removed after this time. Whole ruminal contents were sampled before feeding, immediately after feed removal and 1, 2, 3, 4, 6, 8, 10 and 12 h after feed removal. A crossover design with split-plot in time was used with four observations per time point per treatment. Extracellular (E) ammonia and amino acids were determined on high speed supernatants of strained ruminal fluid. Total (T) ammonia and amino acids were obtained by lysing microbial cells with 1% cetyltrimethylammonium bromide (CTAB) and one freeze treatment before centrifugation. Intracellular (I) amino acids and ammonia were determined as T minus E. Squeezed particles were suspended in .1 N HCl containing 1% CTAB. Total and E ammonia were higher throughout the study for no monensin vs monensin (P less than .05). Intracellular ammonia was low (.03 to 1 mM) and did not change (P greater than .10) across time for either dietary treatment. Intracellular amino acids ranged from 1.2 to 4.5 mM and were higher (P less than .05) than E amino acids (.9 to 2.2 mM) for both diets immediately after feeding. Monensin did not significantly lower (P greater than .10) T amino acids compared with no monensin throughout sampling (2.6 and 3.1 mM, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Total and individual amino acids in strained ruminal liquor from cows fed graded amounts of urea.

Total and individual amino acids were determined in samples of strained ruminal liquor from an experiment in which cows were fed a low protein, high concentrate diet supplemented with graded amounts of urea to elicit a range of ruminal ammonia concentrations. Total amino acids plateaued beyond 2% crude protein from urea and 6.5 mM ruminal ammonia. There was a negative quadratic relationship between concentrations of total amino acids and ammonia with total amino acids maximized at 16.2 mM ammonia. Individual amino acids followed trends similar to that of total amino acids, increasing with dietary urea and ruminal ammonia before plateauing or declining slightly. Contribution to the animal's amino acid requirements from passage of free amino acids in strained ruminal liquor were estimated for three essential amino acids. Based on mean concentration in strained ruminal liquor, liquid turnover rates, and requirements for gain, 7, 16, and 12% of the requirements for methonine, lysine, and threonine may be contributed from passage of ruminal free amino acids.

Effect of heat treatment on true digestibility in the rat, in vitro proteolysis and available lysine content of cottonseed meal protein.

Effects of heating cottonseed meal (CSM) protein were quantitatively assessed by determination of true digestibility (TD), in vitro proteolysis, N solubility and fluorodinitrobenzene (FDNB) available lysine. Flaked, dehulled cottonseed was extracted with hexane and desolventized at 25 C, then autoclaved (121 C, 1.1 kg/cm(2)) for 0, 15, 30, 60, 90 or 120 minutes. Free gossypol was subsequently extracted, and TD was determined in weanling rats. Metabolic fecal N (the fecal N excreted by rats fed a basal diet containing 4% casein protein) was 1.84 +/- .10 mg N/g dry matter intake. TD and FDNB-available lysine (percentage of total) were 91 and 89%, respectively, in the unheated meal. TD and FDNB-available lysine were reduced to 84 and 78% after 60 min of autoclaving, and to 71 and 44% after 120 min of autoclaving. The effect of heat treatment on TD was described by the equation: % TD = 100 - 9.28e(.0096t) (r = .998), where t = minutes of autoclaving. This indicated an accelerated decline in TD as heating time increased. No more than 40% of the loss in FDNB-available lysine was attributable to gossypol binding. In vitro release of total amino acids from autoclaved CSM samples during pepsin-pancreatin incubations was highly correlated to TD (r = .996), but N solubility in .02 N NaOH was poorly correlated to TD. In samples of solvent-extracted and screw-pressed CSM, TD (estimated from pepsin-pancreatin incubations) ranged from 80 to 85% and FDNB-available lysine ranged from 73 to 85%, and both were only slightly lower in screw-pressed than in solvent-extracted meals. Intake of FDNB-available lysine was correlated (r = .902) to weight gain in rats fed diets containing the CSM that were more severely autoclaved. Results suggest that heat treatment must be more severe than that which normally occurs in commercial CSM processing to cause substantial, selective loss in lysine availability.

Effect of heat treatment on ruminal degradation and escape, and intestinal digestibility of cottonseed meal protein.

The effect of heat treatment of ruminal protein degradation and escape was studied using in vitro incubations with autoclaved and commercial cottonseed meal (CSM) samples. Incubations using high ratios of protein to ruminal fluid appeared to overestimate ruminal degradation of CSM protein relative to casein. A biexponential model, assuming CSM contained two protein fractions degraded at two different rates, was used to interpret data from in vitro incubations conducted using ratios of protein to ruminal fluid similar to those expected in vivo. The first fraction was degraded at rates (0.68-1.19/hour) which were 2--3 1/2 times greater than that of casein (0.34/hour). Degradation rates of the second fraction were much slower (0.011-0.093/hour). The effect of heat treatment was to decrease the proportion of the rapidly degraded fraction and to both increase the proportion and to decrease the degradation rate of the more slowly degraded fraction. Estimated ruminal escape increased with each increment of heat treatment. Intestinal protein digestibility (ruminal escape times true digestibility) increased to maximum at 60 minutes autoclaving, and then declined. Estimates of intestinal protein digestibility averaged 30.6 and 50.3% for solvent-extracted and screw-press CSM, respectively. These and previous results suggest heat treatment decreases ruminal degradation partly by blocking reactive sites for microbial proteolytic enzymes and partly by reducing protein solubility.