51 research outputs found

    The effect of grazing pressure on rotationally grazed pastures in spring/early summer on subsequent sward characteristics

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    peer-reviewedTwo experiments (E1 and E2) were carried out to examine the effect of grazing pressure (GP) in the early part of the grazing season on subsequent sward composition. Three GP levels, equating to 6.35, 4.24 and 3.53 cows/ha in E1, and 6.06, 5.05 and 4.03 cows/ha in E2, were used. The GP treatments were applied between April and July in E1, and April and June in E2. As GP decreased different swards, termed high (HQ), medium (MQ) and low (LQ) quality, were created. The post-grazing sward heights at the end of the GP periods were 6.6, 10.5 and 14.6 (s.e. 0.78) cm in E1, and 5.9, 8.8 and 11.4 (s.e. 0.39) cm in E2, for HQ, MQ and low LQ, respectively. Organic matter digestibility coefficients for herbage from the HQ, MQ and LQ swards during the subsequent grazing cycles averaged 0.770, 0.729 and 0.702 (s.e. 0.0055) in E1, and 0.761, 0.731 and 0.711 (s.e. 0.0038) in E2, respectively. Average live leaf proportions of the HQ, MQ and LQ swards were 0.583, 0.427 and 0.329 (s.e. 0.0193) in E1, and 0.600, 0.474 and 0.362 (s.e. 0.0155) in E2, respectively. GP had a significant effect on the proportion of grass area categorised as short grass (SG). The proportions of SG area in HQ, MQ and LQ were 0.711, 0.579 and 0.445 (s.e. 0.0106), respectively, in E1, and 0.700, 0.556 and 0.441 (s.e. 0.0133), respectively, in E2. Pre-grazing herbage mass (dry matter above 45 mm) was 2,065, 2,736 and 3,700 (s.e. 144.1) kg/ha for HQ, MQ and LQ, respectively, in E1 and 2,688, 3,735 and 4,722 (s.e. 145.0) kg/ha for HQ, MQ and LQ, respectively, in E2. The results show the importance of early season grazing pressure in creating a leafy high-digestibility sward for the remainder of the grazing season

    The effect of grazing pressure on rotationally grazed pastures in spring/early summer on the performance of dairy cows in the summer/autumn period

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    peer-reviewedTwo experiments (E1 and E2) were carried out to examine the effects of sward type (ST) on dairy cow performance. Applying grazing pressures (GP) in spring/early summer of 6.35, 4.24 and 3.53 cows/ha in E1, and 6.06, 5.05 and 4.03 cows/ha in E2, created the different ST. From summer to autumn, two stocking rates (SR) were applied to each sward, i.e., high (HR) and low (LR). As GP was reduced, the swards were characterised by progressively higher herbage mass of lower organic matter digestibility (OMD) and live leaf (LL) proportion, termed high (HQ), medium (MQ) and low (LQ) quality. There was no interaction between ST and SR for any animal performance variables except for grazing time. Mean diet OMD was 0.816, 0.803 and 0.794 (s.e. 0.0029) in E1, and 0.793, 0.780 and 0.772 (s.e. 0.0021) in E2, for HQ, MQ and LQ, respectively. The corresponding values for LL were 0.785, 0.740 and 0.709 (s.e. 0.0121) in E1, and 0.825, 0.790 and 0.759 (s.e. 0.0095) in E2. Milk yield per cow was 13.2, 12.2 and 10.6 (s.e. 0.55) kg in E1, and 18.4, 17.5 and 16.2 (s.e. 0.32) kg in E2, for HQ, MQ and LQ, respectively. Milk yields were 11.1 and 12.9 (s.e. 0.46) kg in E1, and 16.4 and 18.3 (s.e. 0.26) kg in E2, for HR and LR, respectively. There was no effect of ST or SR on milk composition or body weight gain. Herbage organic matter intake was 12.8, 12.5 and 11.1 (s.e. 0.28) kg in E2, for HQ, MQ and LQ, respectively. The corresponding values were 11.4 and 12.9 (s.e. 0.23) kg for HR and LR, respectively. The results show that milk yield of springcalving dairy cows is higher in summer when high rather than low stocking rates are applied in spring/early summer. The increased milk production is attributed to higher intake of herbage of higher nutritive value

    The effect of herbage mass and allowance on herbage intake, diet composition and ingestive behaviour of dairy cows

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    peer-reviewedAn experiment was conducted to examine the effects of herbage mass [HM, based on regrowth intervals of 35 (T) and 21 (S) days] and herbage allowance [HA, 20.2 (H) and 12.7 (L) kg organic matter (OM)/cow] on herbage OM intake (OMI), dietary composition and ingestive behaviour of dairy cows. Four groups of three cows each were used in a 4 × 4 greco-latin square design along with four oesophageal-fistulated cows. The treatment periods were 7 days and the squares (SQ) were repeated three times in a balanced way. The experiment was conducted from 11 April to 3 July 1986. The HM (organic matter) above 3 cm was 3064, 3472 and 3515 kg/ha for T and 2395, 1113 and 2396 kg/ha (s.e. 94) for S, for SQ 1 to 3, respectively. Organic matter digestibility (OMD) was 842, 799 and 778 g/kg for T, and 851, 842 and 804 g/kg for S (s.e. 0.9), for SQ 1 to 3, respectively. Sward height (cm) after grazing was 8.5 and 7.6 for T and S, and 9.6 and 6.5 for H and L (s.e. 0.18), respectively. OMI was 15.2, 14.8 and 15.2 kg for TH, 12.3, 11.9 and 10.7 kg for TL, 15.8, 14.8 and 14.5 kg for SH and 11.9, 11.1 and 11.2kg for SL (s.e. 0.24), for SQ 1 to 3, respectively. The OMD of the diet was closely related to proportion of live leaf in the diet and sward OMD. Average biting rate increased with decreasing HM (R2 0.65). Grazing time was 8.93, 9.11 and 9.06 h for TH, 8.13, 7.96 and 7.91 h for TL, 8.96, 9.59 and 9.29 h for SH and 8.56, 9.36 and 8.52 h for SL (s.e. 0.155), for SQ 1 to 3, respectively. Multiple regression analysis showed that OMI was significantly related to HM (+0.48 kg/t), OMD of the sward (+0.18 kg per 10 g/kg) and pre-experimental milk yield (+0.37 kg/kg) (R2 0.89). The increase in OMI with potential milk yield, as indicated by pre-experimental yield, accounted for 0.80 of the supplementary energy requirements.National Development Plan 2000-200

    Effects of daily herbage allowance and stage of lactation on the intake and performance of dairy cows in early summer

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    peer-reviewedThis research was part-funded by European Union Structural Funds (EAGGF).The aim of this study was to investigate the relationship between daily herbage allowance (DHA) and the performance of dairy cows at two stages of lactation. Spring-calving (n=42, mean calving date 17 February) and autumn-calving (n=42, mean calving date 22 September) Friesian cows were divided into three equal groups and assigned to three levels of DHA (above a cutting height of 35 mm), 17 (L), 20 (M) and 23 (H) kg of dry matter (DM) per head, from late April to late June, 1996. The spring-calving cows grazed to sward heights (mm) of 47, 56 and 65 (s.e. 0.6) and residual herbage organic matter (OM) masses (above 35 mm) of 294, 408 and 528 (s.e. 12.1) kg/ha for L, M and H, respectively. The autumn-calving cows grazed to corresponding sward heights of 51, 60 and 69 (s.e. 1.1) mm and leftresidual herbage OM masses of 364, 445 and 555 (s.e. 12.9) kg/ha for L, M and H, respectively. Pastures were mechanically topped post grazing. Spring-calving cows consumed 13.3, 14.7 and 15.5 kg OM (s.e. 0.47) per day, and autumn-calving cows consumed 13.3, 13.8 and 14.9 kg OM (s.e. 0.43) per day for L, M and H, respectively. Mean daily solids-corrected milk yield was 23.1, 23.8 and 24.8 (s.e. 0.34) kg for the spring-calving cows, and 17.5, 18.4 and 18.7 (s.e. 0.35) kg for the autumncalving cows, for L, M and H, respectively. Milk yield could be predicted from preexperimental yield (PMY) and daily herbage organic matter allowance (DOMA, kg) according to the following equation: y = −1.13 + 0.76 (s.e. 0.030) PMY + 0.22 (s.e. 0.057) DOMA (r.s.d. 1.32, R2 0.89). The results indicate that high individual cow and herd production levels can be achieved from high quality herbage alone during early summer at a DHA of 23 kg DM for spring-calving cows and 20 kg DM for autumn-calving cows.European Unio

    A Comparison of Perennial Ryegrass Cultivars Differing in Heading Date and Grass Ploidy for Grazing Dairy Cows at Two Different Stocking Rates

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    Animal productivity is the ultimate performance indicator of any new grass cultivar. Direct assessment is complex and expensive. Recent research has identified a number of important sward factors that influence intake and production. The most important factor appears to be green leaf mass. The objective of this two year study was to investigate the effects on milk yield, composition and grass intake of grass cultivars with contrasting heading dates (HD) and grass ploidies (PL) when grazed at different stocking rates

    Emergency surgery for splenic flexure cancer: results of the SFC Study Group database

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    Background: The effectiveness of surgical treatment for splenic flexure carcinomas (SFCs) in emergency settings remains unexplored. This study aims to compare the perioperative and long-term outcomes of different alternatives for emergency SFC resection. Method: This multicenter retrospective study was based on the SFC Study Group database. For the present analysis, SFC patients were selected if they had received emergency surgical resection with curative intent between 2000 and 2018. Extended right colectomy (ERC), left colectomy (LC), and segmental left colectomy (SLC) were evaluated and compared. Results: The study sample was composed of 90 SFC patients who underwent emergency ERC (n = 55, 61.1%), LC (n = 18, 20%), or SLC (n = 17, 18.9%). Bowel obstruction was the most frequent indication for surgery (n = 75, 83.3%), and an open approach was chosen in 81.1% of the patients. A higher incidence of postoperative complications was observed in the ERC group (70.9%) than in the LC (44.4%) and SLC groups (47.1%), with a significant procedure-related difference for severe postoperative complications (Dindo-Clavien ≥ III; adjusted odds ratio for ERC vs. LC:7.23; 95% CI 1.51-34.66; p = 0.013). Anastomotic leakage occurred in 8 (11.2%) patients, with no differences between the groups (p = 0.902). R0 resection was achieved in 98.9% of the procedures, and ≥ 12 lymph nodes were retrieved in 92.2% of patients. Overall and disease-free survival rates at 5 years were similar between the groups and were significantly associated with stage pT4 and the presence of synchronous metastases. Conclusion: In the emergency setting, ERC and open surgery are the most frequently performed procedures. ERC is associated with increased odds of severe postoperative complications when compared to more conservative SFC resections. Nonetheless, all the alternatives seem to provide similar pathologic and long-term outcomes, supporting the oncological safety of more conservative resections for emergency SFCs

    Mortality by age, gene and gender in carriers of pathogenic mismatch repair gene variants receiving surveillance for early cancer diagnosis and treatment: a report from the prospective Lynch syndrome database

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    BACKGROUND: The Prospective Lynch Syndrome Database (PLSD) collates information on carriers of pathogenic or likely pathogenic MMR variants (path_MMR) who are receiving medical follow-up, including colonoscopy surveillance, which aims to the achieve early diagnosis and treatment of cancers. Here we use the most recent PLSD cohort that is larger and has wider geographical representation than previous versions, allowing us to present mortality as an outcome, and median ages at cancer diagnoses for the first time. METHODS: The PLSD is a prospective observational study without a control group that was designed in 2012 and updated up to October 2022. Data for 8500 carriers of path_MMR variants from 25 countries were included, providing 71,713 years of follow up. Cumulative cancer incidences at 65 years of age were combined with 10-year crude survival following cancer, to derive estimates of mortality up to 75 years of age by organ, gene, and gender. FINDINGS: Gynaecological cancers were more frequent than colorectal cancers in path_MSH2, path_MSH6 and path_PMS2 carriers [cumulative incidence: 53.3%, 49.6% and 23.3% at 75 years, respectively]. Endometrial, colon and ovarian cancer had low mortality [8%, 13% and 15%, respectively] and prostate cancers were frequent in male path_MSH2 carriers [cumulative incidence: 39.7% at 75 years]. Pancreatic, brain, biliary tract and ureter and kidney and urinary bladder cancers were associated with high mortality [83%, 66%, 58%, 27%, and 29%, respectively]. Among path_MMR carriers undergoing colonoscopy surveillance, particularly path_MSH2 carriers, more deaths followed non-colorectal Lynch syndrome cancers than colorectal cancers. INTERPRETATION: In path_MMR carriers undergoing colonoscopy surveillance, non-colorectal Lynch syndrome cancers were associated with more deaths than were colorectal cancers. Reducing deaths from non-colorectal cancers presents a key challenge in contemporary medical care in Lynch syndrome. FUNDING: We acknowledge funding from the Norwegian Cancer Society, contract 194751-2017

    Colorectal cancer incidences in Lynch syndrome: a comparison of results from the prospective lynch syndrome database and the international mismatch repair consortium

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    Objective To compare colorectal cancer (CRC) incidences in carriers of pathogenic variants of the MMR genes in the PLSD and IMRC cohorts, of which only the former included mandatory colonoscopy surveillance for all participants. Methods CRC incidences were calculated in an intervention group comprising a cohort of confirmed carriers of pathogenic or likely pathogenic variants in mismatch repair genes (path_MMR) followed prospectively by the Prospective Lynch Syndrome Database (PLSD). All had colonoscopy surveillance, with polypectomy when polyps were identified. Comparison was made with a retrospective cohort reported by the International Mismatch Repair Consortium (IMRC). This comprised confirmed and inferred path_MMR carriers who were first- or second-degree relatives of Lynch syndrome probands. Results In the PLSD, 8,153 subjects had follow-up colonoscopy surveillance for a total of 67,604 years and 578 carriers had CRC diagnosed. Average cumulative incidences of CRC in path_MLH1 carriers at 70 years of age were 52% in males and 41% in females; for path_MSH2 50% and 39%; for path_MSH6 13% and 17% and for path_PMS2 11% and 8%. In contrast, in the IMRC cohort, corresponding cumulative incidences were 40% and 27%; 34% and 23%; 16% and 8% and 7% and 6%. Comparing just the European carriers in the two series gave similar findings. Numbers in the PLSD series did not allow comparisons of carriers from other continents separately. Cumulative incidences at 25 years were < 1% in all retrospective groups. Conclusions Prospectively observed CRC incidences (PLSD) in path_MLH1 and path_MSH2 carriers undergoing colonoscopy surveillance and polypectomy were higher than in the retrospective (IMRC) series, and were not reduced in path_MSH6 carriers. These findings were the opposite to those expected. CRC point incidence before 50 years of age was reduced in path_PMS2 carriers subjected to colonoscopy, but not significantly so
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