To examine effects of nutritional plane and Se supplementation on colostrum quality and mammary development, individually fed, pregnant Rambouillet ewe lambs were allotted randomly to 1 of 6 treatments in a 2 x 3 factorial arrangement. Main effects included dietary Se level, which began at breeding (d = 0) [adequate Se (9.5 mug/kg of BW) vs. high Se (81.8 mug/kg of BW)], and plane of nutrition, which began at d 50 of gestation [60% (RES), 100% (CON), and 140% (HIGH) of requirements]. Upon parturition, lambs were immediately separated from dams and weighed. Three hours after lambing, colostrum yield was determined, and samples were obtained for components and immunoglobulin G (IgG) analysis. Ewes were slaughtered within 24 h of parturition, and mammary tissues were collected for determination of alveolar secretory epithelial cell proliferation index and luminal area. Gestation length was reduced (P < 0.01) in HIGH ewes compared with RES and CON ewes. Although birth weights were reduced (P < 0.01) in RES and HIGH compared with CON ewes, there was little effect of diet on placental size. Mammary gland weight was reduced (P = 0.05) in RES compared with CON and HIGH, which were similar. However, when expressed as grams per kilogram of BW, mammary gland weight in HIGH ewes was less (P = 0.03) compared with RES and CON. Colostrum weight and volume were reduced (P < 0.01) in RES and HIGH ewes compared with CON. Although colostrum IgG concentration was greater in RES ewes compared with CON and HIGH, total IgG was lower (P = 0.06) in RES and HIGH compared with CON ewes. The percentage of alveolar cells proliferating was increased (P < 0.04) in HIGH compared with RES ewes, with CON being intermediate. Percentage of alveoli luminal area per unit tissue area was increased (P = 0.04) in RES compared with HIGH and CON ewes, which did not differ. Selenium had no effect (P >/= 0.15) on mammary gland weight, colostrum quantity, or IgG concentration in pregnant ewe lambs. Improper nutrition from mid to late pregnancy in ewe lambs altered colostrum quality and quantity and reduced offspring birth weight, which may have negative implications for lamb health and survival during the early postnatal period.
To examine effects of nutrient restriction and dietary Se on maternal and fetal visceral tissues, 36 pregnant Targhee-cross ewe lambs were allotted randomly to 1 of 4 treatments in a 2 x 2 factorial arrangement. Treatments were plane of nutrition [control, 100% of requirements vs. restricted, 60% of controls] and dietary Se [adequate Se, ASe (6 microg/kg of BW) vs. high Se, HSe (80 microg/kg of BW)] from Se-enriched yeast. Selenium treatments were initiated 21 d before breeding and dietary restriction began on d 64 of gestation. Diets contained 16% CP and 2.12 Mcal/kg of ME (DM basis) and differing amounts were fed to control and restricted groups. On d 135 +/- 5 (mean +/- range) of gestation, ewes were slaughtered and visceral tissues were harvested. There was a nutrition x Se interaction (P = 0.02) for maternal jejunal RNA:DNA; no other interactions were detected for maternal measurements. Maternal BW, stomach complex, small intestine, large intestine, liver, and kidney mass were less (P < or = 0.01) in restricted than control ewes. Lung mass (g/kg of empty BW) was greater (P = 0.09) in restricted than control ewes and for HSe compared with ASe ewes. Maternal jejunal protein content and protein:DNA were less (P < or = 0.002) in restricted than control ewes. Maternal jejunal DNA and RNA concentrations and total proliferating jejunal cells were not affected (P > or = 0.11) by treatment. Total jejunal and mucosal vascularity (mL) were less (P < or = 0.01) in restricted than control ewes. Fetuses from restricted ewes had less BW (P = 0.06), empty carcass weight (P = 0.06), crown-rump length (P = 0.03), liver (P = 0.01), pancreas (P = 0.07), perirenal fat (P = 0.02), small intestine (P = 0.007), and spleen weights (P = 0.03) compared with controls. Fetuses from HSe ewes had heavier (P < or = 0.09) BW, and empty carcass, heart, lung, spleen, total viscera, and large intestine weights compared with ASe ewes. Nutrient restriction resulted in less protein content (mg, P = 0.01) and protein:DNA (P = 0.06) in fetal jejunum. Fetal muscle DNA (nutrition by Se interaction, P = 0.04) concentration was greater (P < 0.05) in restricted ewes fed HSe compared with other treatments. Fetal muscle RNA concentration (P = 0.01) and heart RNA content (P = 0.04) were greater in HSe vs. ASe ewes. These data indicate that maternal dietary Se may alter fetal responses, as noted by greater fetal heart, lung, spleen, and BW.
The online version of this article, along with updated information and services, is located on www.asas.orgThis article is a U.S. government work, and is not subject to copyright in the United States. and lambs were removed at parturition. Colostrum was milked from all ewes at 3 h postpartum, and one-half of the ewes (n = 42) were transitioned to a common diet meeting lactation requirements and mechanically milked for 20 d. Colostrum yield was greater (P = 0.02) for HSe ewes than ASe, whereas CON had greater (P < 0.05) colostrum yield than RES and HIH. Colostrum Se (%) was greater (P < 0.01) for HSe than ASe. Colostrum from ewes fed HSe had less (P = 0.03) butterfat (%), but greater (P ≤ 0.05) total butterfat, solids-notfat, lactose, protein, milk urea N, and Se than ASe. Colostrum from HIH ewes had greater (P ≤ 0.02) solids-not-fat (%) than RES, whereas RES had greater (P ≤ 0.04) butterfat (%) than CON and HIH. Colostrum from ewes fed the CON diet had greater (P = 0.01) total butterfat than HIH. Total solids-not-fat, lactose, and protein were greater (P < 0.05) in colostrum from CON than RES and HIH. Ewes fed HSe had greater (P < 0.01) milk yield (g/d and mL/d) than ASe, and CON and HIH had greater (P < 0.01) yield than RES. Milk protein (%) was greater (P ≤ 0.01) in RES compared with CON or HIH. Ewes fed HSe had greater (P < 0.01) milk Se (μg/g and mg/d) than ASe on each sampling day. Milk from CON and HIH ewes had greater (P < 0.01) total solids-not-fat, lactose, protein, and milk urea N than RES. Total Se was greater (P = 0.02) in milk from ewes fed the CON diet compared with RES. Somatic cell count and total somatic cells were greater (P ≤ 0.05) in milk from CON than RES. A cubic effect of day (P ≥ 0.01) was observed for milk yield (g and mL). Butterfat, solids-not-fat, lactose, milk urea N, and Se concentration responded quadratically (P ≤ 0.01) to day. Protein (%), total butterfat, and total Se, and somatic cells (cells/mL and cells/d) decreased linearly (P < 0.01) with day. Results indicate that gestational nutrition affects colostrum and milk yield and nutrient content, even when lactational nutrient requirements are met.
To investigate the effects of nutritional plane and Se supply during gestation on ewe and offspring performance and body composition, 84 Rambouillet ewe lambs (age = 240 +/- 17 d, BW = 52.1 +/- 6.2 kg) were allocated to a 2 x 3 x 2 factorial arrangement of treatments. Factors included Se [adequate Se (ASe, 11.5 microg/kg of BW) or high Se (HSe, 77.0 microg/kg of BW)] initiated at breeding, nutritional plane [60% (restricted, RES), 100% (control, CON), or 140% (high, HIH) of NRC requirements] initiated at d 40 of gestation, and physiological stage at necropsy [3 to 24 h postpartum or d 20 of lactation]. Ewes were fed and housed individually in a temperature-controlled facility. At parturition, all lambs were removed and artificially reared until necropsy on d 20.6 +/- 0.9 of age. Ewes assigned to the treatment at d 20 of lactation were transitioned to a common diet meeting lactation requirements and were mechanically milked. From d 95 of gestation through parturition and d 20 of lactation, ewe BW and BCS were least (P
The objectives were to evaluate effects of maternal nutrient restriction and stage of gestation on maternal and fetal visceral organ mass and indices of jejunal growth and vascularity in beef cows. Thirty multiparous beef cows (BW = 571 +/- 63 kg; BCS = 5.4 +/- 0.7) carrying female fetuses (d 30 of gestation) were allocated to receive a diet of native grass hay (CON; 12.1% CP, 70.7% IVDMD, DM basis) to meet NRC recommendations for BW gain during early gestation or a nutrient-restricted diet of millet straw (NR; 9.9% CP, 54.5% IVDMD, DM basis) to provide 68.1% of NE(m) and 86.7% of MP estimated requirements. On d 125 of gestation, 10 CON and 10 NR cows were killed and necropsied. Five remaining CON cows received the CON diet, and 5 NR cows were realimented with a concentrate supplement (13.2% CP, 77.6% IVDMD, DM basis) and the CON hay to achieve a BCS similar to CON cows by d 220 of gestation. Remaining cows were necropsied on d 245 of gestation. Cow BW and eviscerated BW (EBW) were less (P < 0.01) for NR than CON at d 125 but did not differ (P > 0.63) at d 245. Cows fed the CON diet had greater (P < 0.09) total gastrointestinal (GI) tract, omasal, and pancreatic weights. Stomach complex, ruminal, and liver weights were greater for CON than NR cows (P < 0.09) on d 125. Total GI, stomach complex, and pancreatic weights increased (P < 0.001) with day of gestation. Restricted cows had decreased (P = 0.09) duodenal RNA:DNA compared with CON. Duodenal DNA was less (P = 0.01) and jejunal RNA:DNA (P = 0.09) was greater for cows at d 125 vs. 245. Cow jejunal capillary area density increased with day of gestation (P = 0.02). Fetal BW and EBW were unaffected by dietary treatment (P > or = 0.32). Total GI tract and all components increased in mass with day of gestation (P < 0.001). Fetuses from NR dams had greater (P = 0.003) reticular mass at d 245 than CON fetuses. Fetuses from NR cows had greater (P = 0.02) percent jejunal proliferation at d 125 and greater (P = 0.03) total intestinal vascularity (mL) at d 245. Fetal jejunal DNA decreased (P = 0.09), RNA:DNA increased (P = 0.05), and total jejunal proliferating cells increased (P < 0.001) with day of gestation. Jejunal capillary area density, number density, and surface density were greater (P < 0.008) during late gestation. Results indicate that maternal and fetal intestines undergo changes during gestation, which can be affected by nutrient restriction and may partially explain differences observed in fetal development and postnatal performance.
Twelve crossbred steers (351 +/- 24 kg initial BW) were used to determine effects of high-Se wheat on visceral tissue mass, intestinal cell growth, and intestinal cellularity and vascularity. Steers were allotted randomly by BW to one of two treatments consisting of 75% concentrate diets that supplied 1) adequate Se concentration (7 to 12 microg x kg x BW(-1) x d(-1)) or 2) high-Se concentration (60 to 70 microg x kg x BW(-1) x d(-1)). Diets were similar in composition, including 25% grass hay, 25% wheat, 39% corn, 5% desugared molasses, and 6% wheat middlings supplement on a DM basis. In the Se treatment, high-Se wheat (10 ppm Se, DM basis) was replaced with low-Se wheat (0.35 ppm Se, DM basis). Diets were formulated to be similar in CP and energy (14.0% CP, 2.12 Mcal of NEm/kg, and 1.26 Mcal NEg/kg of DM) and were offered daily (1500) to individual steers in an electronic feeding system. Diets were fed at 2.38% BW. After 126 d, steers were slaughtered, and individual visceral tissue weights determined. Concentrations of DNA, RNA, and protein of duodenum, ileum, and total small intestine were not affected (P > or = 0.33) by treatment. Similarly, RNA:DNA and protein:DNA ratios in duodenum, jejunum, ileum, and whole small intestine were not (P > or = 0.33) affected by feeding high-Se wheat. Conversely, jejunal weight was greater (P < 0.002) in steers fed high-Se wheat than in controls (916 vs. 1,427 +/- 84 g). Jejunal DNA was increased (P < 0.04) in steers fed high-Se wheat (2.95 vs. 3.56 +/- 0.19 mg/g), suggesting increased cell number. Concentrations of jejunal RNA and protein were not altered by treatment; however, because the jejunal weight increased in high-Se steers, DNA, RNA, and protein contents (grams) were greater than in control steers (P < 0.05). Vascularity of jejunal tissue decreased (P < 0.10) with high-Se wheat; however, because jejunal mass was greater for the high-Se wheat treatment, total microvascular volume was not affected by treatment. Percentage of jejunal crypt cell proliferation was not affected (P = 0.48) by treatment; however, total number of cells proliferating within the jejunum was increased in steers fed high-Se wheat. Data indicate that the lower jejunal vascularity in the diet high in Se (provided from wheat) may have resulted in increased jejunal mass to meet physiological nutrient demand. Therefore, negative effects of Se level used in this study on productive performance of feedlot steers are not expected.
This study investigated the effects of strenuous live-fire firefighting drills and a 90 min recovery period on selected hormonal, immunological and psychological variables. Apparently healthy, male, professional firefighters (n = 11) performed three trials of standardized firefighting tasks in a live-fire training structure. There was significant leukocytosis immediately post firefighting activity that persisted following recovery, although there was a variable response among the leukocyte subsets. Most notable was the decrease in number and percentage of lymphocytes following 90 min of recovery. Plasma levels of ACTH and cortisol were significantly elevated post firefighting activity and cortisol remained elevated following 90 min of recovery. Elevated cortisol immediately following activity was related to reduced feelings of energy. These data demonstrate the magnitude of the physiological and psychological disruption following strenuous firefighting activity and suggest that immune function may be altered following such activity. This is a finding that may have practical consequences for this group of first responders.
The catac1astic rocks in the Alpine Fault Zone fall into three distinct groups: (a) fault pug, fault breccia, and shattered rock, (b) catac1asite, mortared and brecciated rock, and (c) mylonite, augen mylonite, ultramylonite, and blastomylonite. The first group is related to Quaternary movements at the junction of schist and granite; the zone of shattered schist is several chains or more in width, and the fault pug and fault breccia a few feet to more than 100 ft wide. The second group is conspicuous in the granitic rocks, the structureless cataclasite being 100-200 ft thick, and the zone of brecciated and mortared granite a mile or more in width, The mylonite group is characterised by fluxion banding and forms a belt 1,000-2,500 ft wide, largely within the granite. The age of formation of the mylonite and cataclasite is uncertain but a key tectonic horizon is the blastomylonite, which shows features of both dislocation and regional metamorphism. The evidence of the blastomylonite, and the comparable mineral assemblages of the schist and mylonite, point to the mylon· itisation being penecontemporaneous with the regional metamorphism of the Rangitata Orogeny (late Jurassic and early Cretaceous)
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