25 research outputs found
Nutrient intake in the bovine during early and mid-gestation causes sex-specific changes in progeny plasma IGF-I, liveweight, height and carcass traits
No full textFetal and postnatal growth are mediated by insulin-like growth factors (IGFs) and their binding proteins (IGFBPs). Maternal nutrient intake during gestation can program the postnatal IGF-axis. This may have significant economic implications for beef cattle production. We investigated the effect of high (H=240%) and low (L=70%) levels of recommended daily crude protein (CP) intake for heifers during the first and second trimesters of gestation in a two-by-two factorial design on progeny (n=68) plasma IGF-I, IGF-II, total IGFBP (tIGFBP), postnatal growth and carcass traits. Calves were heavier at birth following high CP diets during the second trimester (P=0.03) and this persisted to 29d. Plasma IGF-I concentrations of males were greater for HL compared to LL (P0.04) from 29 to 657d, and for LH compared to LL from 29 until 379d (P=0.02). Exposure to low CP diets during the first trimester resulted in heavier males from 191d onwards (P=0.04) but a tendency for lighter females from 552d onwards (P=0.07) that had lighter carcass weights (P=0.04). Longissimus dorsi cross-sectional area of all carcasses was greater following exposure to low CP diets during the second trimester (P=0.04). Heifer nutrient intake during the first and second trimesters causes persistent and sex-specific programming of progeny plasma IGF-I, postnatal liveweight and carcass weight. Refining heifer nutritional programs during early gestation may optimize production objectives in progeny.G.C. Micke, T.M. Sullivan, K.L. Gatford, J.A. Owens and V.E.A. Perr
Morphometric and gene expression analyses of stromal expansion during development of the bovine fetal ovary
No full textDuring ovarian development stroma from the mesonephros penetrates and expands into the ovarian primordium and thus appears to be involved, at least physically, in the formation of ovigerous cords, follicles and surface epithelium. Cortical stromal development during gestation in bovine fetal ovaries (n = 27) was characterised by immunohistochemistry and by mRNA analyses. Stroma was identified by immunostaining of stromal matrix collagen type I and proliferating cells were identified by Ki67 expression. The cortical and medullar volume expanded across gestation, with the rate of cortical expansion slowing over time. During gestation, the proportion of stroma in the cortex and total volume in the cortex significantly increased (P 0.05). The expression levels of 12 genes out of 18 examined, including osteoglycin (OGN) and lumican (LUM), were significantly increased later in development (P < 0.05) and the expression of many genes was positively correlated with other genes and with gestational age. Thus, the rate of cortical stromal expansion peaked in early gestation due to cell proliferation, whilst late in development expression of extracellular matrix genes increased.M.D. Hartanti, A K. Hummitzsch, H.F. Irving-Rodgers, W.M. Bonner, K.J. Copping, R.A. Anderson, I.C. McMillen, V.E.A. Perry and R.J. Rodger
The influence of an Ecobeach PEM on beach development
No full textSince the end of 2006 in the Netherlands a test is going on with a passive beach drainage system called Ecobeach. The system consists of vertical draining tubes with a length of 2.0 m called PEMs (Pressure Equalizing Modules). Under the surface level, every 100 m a row of PEMs is installed between the high and low waterline. Ecobeach is a Danish invention and the inventor claims that at beaches at different places around the world the volume of sand is increased thanks to the PEMs. This “drainage system” differs from other beach drainage systems in the way that normally horizontal drains are being placed under the beach, connected by a pump. When the Dutch test started very little was known about the functioning of the PEM system. For this reason scientific research to the PEMs was being started in September 2008. First the situation in the test area is examined. The beach, and especially the swash zone, is a complex area, influenced by tides, waves, sediment transport and groundwater flows. Five hypotheses are formulated of the influence PEMs can have on their environment. If a PEM can influence the groundwater behaviour in its direct vicinity, a process can be initiated which has an effect on the total beach. The initial events, caused directly by the PEMs, have to be studied in the field to make clear if the different hypothesised processes are realistic. Moreover consequences of the possible processes initiated by the PEMs should be recognized if anything happens. For this reason a fieldwork is executed in August-September 2009. Measurement results of the groundwater behaviour in the vicinity of PEMs show that some hypotheses are unlikely, and some are still questionable. An analysis of the sediment in and around the test area makes clear that possibly a process is going on in the Ecobeach test area, which could be a result of the PEMs. Because this study will be continued, this report shows an initial study to a very complex system. It shows the setup of a large study, interesting analysis methods and surprising results. Nevertheless it will lead sometimes to new questions.Coastal EngineeringHydraulic EngineeringCivil Engineering and Geoscience
Dietary manipulation of Bos indicus x heifers during gestation affects the reproductive development of their heifer calves
No full textThe effect of nutrition during the first and second trimesters of pregnancy in composite beef heifers on reproductive parameters of their female calves was determined in the present study. At artificial insemination, heifers were assigned to one of four treatment groups (i.e. HH, HL, LowH and LL) depending on the level of crude protein intake (H = high; L = low) for first and second trimesters of pregnancy. Gonadotrophin concentrations and ovarian parameters were measured in their female calves at 5 and 23 months of age. Crude protein intake was positively associated with dam plasma urea (P < 0.001). The density of healthy follicles in heifers at the time of death was negatively correlated with dam plasma urea at Day 179 (P = 0.009). Heifers from LowH dams had a smaller-sized prepubertal largest ovarian follicle (P = 0.03) and lower densities of primordial and primary follicles (P = 0.02) and healthy antral follicles (P = 0.009) when they were killed. There was a positive correlation between plasma FSH concentrations at 5 and 23 months of age (P = 0.02), as well as between the sizes of the largest ovarian follicles at 6 and 23 months of age (P = 0.01). In conclusion, the reproductive development of heifers may be affected by prenatal nutrition during early and mid-gestation.T.M. Sullivan, G.C. Micke, R.M. Greer, H.F. Irving-Rodgers, R.J. Rodgers and V.E.A. Perr
The influence of peri-conception and first trimester dietary restriction of protein in cattle on meat quality traits of entire male progeny
No full textAbstract not availableTharcilla I.R.C. Alvarenga, Katrina J. Copping, Xuemei Han, Edward H. Clayton, Richard J. Meyer, Raymond J. Rodgers, I. Caroline McMillen, Viv E.A. Perry, Geert Geesin
Influences of diet during gestation on potential postpartum reproductive performance and milk production of beef heifers
No full textThe influences of nutritional protein and energy during early and mid pregnancy on milk production and postpartum reproductive parameters were determined in 70 beef heifers of two composite breeds (Bos indicus X Bos taurus). At artificial insemination (AI), heifers were divided into four dietary treatment groups identified by the level of protein, and to a lesser extent energy, fed during the first and second trimesters: high/high (HH), high/low (HL), low/high (LH), and low/low (LL). Milk production was lower in the heifers receiving high treatment in first trimester than that in heifers receiving the low treatment (P = 0.01). Milk production was negatively associated with dam body condition score (BCS; P = 0.01), nonesterified fatty acids (P = 0.001), and leptin (P = 0.02) and positively associated with urea (P < 0.001) concentrations during lactation. Increased dietary protein in the first trimester increased or decreased concentrations of colostral protein dependent upon genotype (P = 0.03). Colostral protein was positively associated with bovine pregnancy associated glycoprotein from late gestation (P = 0.007). Milk fat was negatively associated with BCS (P = 0.007) and influenced by genotype (P = 0.003). Dietary treatment did not affect the postpartum reproductive performance of beef heifers. Gestation length (P < 0.001) and the postpartum interval to first estrus (PPI; P = 0.02) were positively associated with calf size. Placental size was negatively associated with placental expulsion time (P < 0.01). Prepartum BCS of the heifers was negatively associated with PPI (P = 0.01). Overall, high levels of nutrition during early gestation are detrimental to milk production in beef heifers
Low dietary protein during early pregnancy alters bovine placental development
No full textTo determine if low dietary protein concentration in the first two trimesters of pregnancy alters placental development, genetically similar heifers from closed herd were fed diets containing different levels of protein in the first and second trimesters of gestation. There were four animals per treatment group, the groups being: L/L = fed a diet containing 7% crude protein (CP) (low protein) in the first and second trimesters; H/H = fed a diet containing 14% CP (high protein) in the first and second trimesters; L/H = fed low protein in the first trimester and high in the second trimester and vice versa for the H/L group. Low protein diets in the first trimester increased dry cotyledon weight at term. Trophectoderm' volume density increased in the H/L and L/H group compared to the L/L and H/H groups. Blood vessel volume and volume density in foetal villi decreased in the H/L and L/H groups compared with the H/H and L/L groups. There was no effect of diet treatment on cotyledon number, diameter or wet weight and no effect on the volume density of connective tissue or fibroblasts in the foetal villi. These results show that a low dietary protein concentration in the first trimester of pregnancy followed by increased protein in the second trimester enhanced placental development. Further, trophectoderm volume was highly correlated with birth weight. Early protein restriction in the pregnant cow may enhance foetal growth in part by stimulating placental growth and function
The Effects of Developmental Programming upon Neonatal Mortality
No full textKEY POINTS- The maternal environment (nutrition and physiologic status) can influence neonatal mortality and morbidity.- The effects of gestational nutrition on birth weight, dystocia, and calf survival vary with the timing and duration of dietary interventions and the sex of the offspring.- The ability to thermoregulate, stand, suckle, and ingest sufficient quantities of colostrum is critical to neonate survival and may be altered by in utero environment.- The quantity of colostral immunoglobulins ingested by the neonate may be affected by prenatal ambient temperature and gestational diet.- Gestational dietary restriction may alter thyroid function and diminish brown adipose tissue capacity concomitantly effecting lymphoid atrophy and neonatal immune function
Dystocia in 3-year-old beef heifers; Relationship to maternal nutrient intake during early- and mid-gestation, pelvic area and hormonal indicators of placental function
No full textThe influence of nutrition during the first and second trimesters of gestation on the occurrence of dystocia was investigated in 3-year-old composite-breed beef heifers. Heifers were allocated according to stratification by weight and genotype to either a high (H/- = 76 MJ metabolisable energy (ME) and 1.4 kg crude protein (CP)), or low (L/- = 62 MJ ME and 0.4 kg CP daily) nutritional treatment on the day of artificial insemination (day 0) to the same Senepol bull. Half of each nutritional group changed to an opposite nutritional group on day 93 of gestation (-/H = 82 MJ ME and 1.4 kg CP; -IL = 63 MJ ME and 0.4 kg CP daily), resulting in four treatment groups: HH (n = 16); HL (n = 19); LH (n = 17); LL (n = 19). From 180 days until calving all heifers were fed the same diets. Pelvic area measures were taken at heifer selection (-72 days) and at 117 days. Maternal circulating concentrations of estrone sulphate (ES), bovine placental lactogen (bPL), bovine pregnancy associated glycoprotein and progesterone were monitored throughout gestation. Heifers were observed continuously over the calving period and delivery type classified as being either eutocic or dystocic. The occurrence of dystocia was 14.1%. Increased calf birth weight increased the odds of occurrence of dystocia (odds ratio (OR) = 1.40; 95% confidence interval (95% CI) 1.12-1.76; P<0.01). High diets in the second trimester were associated with heavier calves at birth (P=0.01). The mean pelvic area of eutocic heifers on -72 cl, tended to be greater compared to that of dystocic heifers (P=0.08) such that a 1-cm(2) difference in pelvic area tended to decrease the risk of dystocia (OR=0.97; 95% CI 0.93-1.01; P=0.09). Longer gestation length was associated with an increased risk of dystocia (P=0.03). ES (P=0.04) and bPL (P=0.09) at calving were positively associated with the risk of dystocia. In conclusion, the current study demonstrates (a) that pelvic area measurement at selection in 3-year-old Bos indicus x Bos taurus heifers may be useful for identifying heifers at an increased risk of dystocia and (b) increased ES and bPL concentrations at calving are associated with increased risk of dystocia. Pelvic area measurements obtained prior to conception remain valid in their assessment of the relationship between pelvic area and likelihood of dystocia occurring in the event of changing maternal nutrient intake during gestation. This is an important finding given maternal diets high in protein and energy during the second trimester of gestation increased calf birth weight and calf birth weight was associated with an increase in the occurrence of dystocia in heifers calving as 3-year olds. (C) 2009 Elsevier B.V. All rights reserved
Maternal periconceptional and first trimester protein restriction in beef heifers: effects on maternal performance and early fetal growth
No full textThis study evaluated the effect of protein restriction during the periconception (PERI) and first trimester (POST) periods on maternal performance, physiology and early fetal growth. Yearling nulliparous heifers (n = 360) were individually fed a diet high or low in protein (HPeri and LPeri respectively) beginning 60 days before conception. From 24 to 98 days post-conception (dpc), half of each treatment group changed to the alternative post-conception high- or low-protein diet (HPost and LPost respectively), yielding four groups in a 2 × 2 factorial design with a common diet until parturition. Protein restriction was associated with lower bodyweight subsequent to reduced (but positive) average daily weight gain (ADG) during the PERI and POST periods. During the POST period, ADG was greater in LPeri than HPeri heifers and tended to be greater in LPost than HPost heifers during the second and third trimester. Bodyweight was similar at term. The pregnancy rate did not differ, but embryo loss between 23 and 36 dpc tended to be greater in LPeri than HPeri heifers. Overall, a greater proportion of male fetuses was detected (at 60 dpc 63.3% male vs 36.7% female). Protein restriction altered maternal plasma urea, non-esterified fatty acids, progesterone, leptin and insulin-like growth factor 1 at critical stages of fetal development. However, profiles varied depending on the sex of the conceptus.Katrina J. Copping, Andrew Hoare, I. Caroline McMillen, Raymond J. Rodgers, Charles R. Wallace and Viv E.A. Perr
