Effects of betaine on growth, carcass characteristics, pork quality, and plasma metabolites of finishing pigs

An experiment was conducted to determine the effect of dietary betaine (0, 0.125, 0.250, or 0.500%) on growth, carcass traits, pork quality, plasma metabolites, and tissue betaine concentrations of cross-bred finishing pigs. Four replications of three pigs (two barrows and one gilt) each were used for each treatment. The basal diet contained 0.85 (69 to 88 kg BW) or 0.65% Lys (88 to 115 kg BW). Overall ADG and gain:feed were not affected (P > 0.10) by betaine, but overall ADFI was decreased (quadratic, P < 0.05; 0 vs betaine, P < 0.01) by betaine; pigs fed 0.250% betaine had the lowest ADFI. Loin muscle area, average back-fat, dressing percentage, percentage lean, total fat, lean:fat, and leaf fat weight were not affected (P > 0.10) by betaine. Tenth-rib backfat thickness was decreased (quadratic, P < 0.05; 0 vs betaine, P < 0.05); pigs fed 0.250% betaine had the lowest 10th-rib backfat thickness. Carcass length was increased (linear, P < 0.05; 0 vs betaine, P < 0.10) as the level of betaine was increased. Fat-free lean, lean gain per day, ham weight, ham fat-free lean, and ham percentage lean were increased (quadratic, P < 0.10), but percentage fat, total ham fat, percentage ham fat, and butt-fat thickness were decreased (quadratic, P < 0.10); these traits were respectively highest or lowest in pigs fed 0.250% betaine. Thaw loss and 24-h pH were increased (quadratic, P < 0.10; 0 vs betaine, P < 0.05) and cook loss was decreased (linear, P < 0.05) in pigs fed betaine. The CIE L* value for the biceps femoris was decreased (quadratic, P < 0.10; 0 vs betaine, P < 0.10); pigs fed 0.250% betaine had the lowest CIE L* value. Subjective color, firmness-wetness, marbling, percentage moisture and bound water of the loin muscle, and shear force were not affected (P > 0.10) by betaine. Betaine was not detectable (< 0.07 mg/g) in the loin muscle of pigs fed 0% betaine, but betaine was detectable and relatively constant in pigs fed 0.125, 0.250, or 0.500% betaine (0.22, 0.17, and 0.21 mg/g, respectively). Plasma urea N, total protein, albumin, triglycerides, and HDL cholesterol concentrations were not affected (P > 0.10). Plasma total cholesterol (linear, P < 0.10) and NEFA (quadratic, P < 0.10) were increased in pigs fed betaine. Betaine improved carcass traits when provided at 0.250% of the diet and improved some aspects of pork quality.     

Agent-based land-use models: a review of applications

Agent-based modelling is an approach that has been receiving attention by the land use modelling community in recent years, mainly because it offers a way of incorporating the influence of human decision-making on land use in a mechanistic, formal, and spatially explicit way, taking into account social interaction, adaptation, and decision-making at different levels. Specific advantages of agent-based models include their ability to model individual decision-making entities and their interactions, to incorporate social processes and non-monetary influences on decision-making, and to dynamically link social and environmental processes. A number of such models are now beginning to appear—it is timely, therefore, to review the uses to which agent-based land use models have been put so far, and to discuss some of the relevant lessons learnt, also drawing on those from other areas of simulation modelling, in relation to future applications. In this paper, we review applications of agent-based land use models under the headings of (a) policy analysis and planning, (b) participatory modelling, (c) explaining spatial patterns of land use or settlement, (d) testing social science concepts and (e) explaining land use functions. The greatest use of such models so far has been by the research community as tools for organising knowledge from empirical studies, and for exploring theoretical aspects of particular systems. However, there is a need to demonstrate that such models are able to solve problems in the real world better than traditional modelling approaches. It is concluded that in terms of decision support, agent-based land-use models are probably more useful as research tools to develop an underlying knowledge base which can then be developed together with end-users into simple rules-of-thumb, rather than as operational decision support tools. This paper arises from research conducted as part of the UK Research Councils’ RELU Programme (award number RES-224-25-0102). RELU is funded jointly by the Economic and Social Research Council, the Biotechnology and Biological Sciences Research Council and the Natural Environment Research Council, with additional funding from the Department for Environment, Food and Rural Affairs and the Scottish Executive Environment and Rural Affairs Department.     

Pollination of the invasive exotic shrub Lupinus arboreus (Fabaceae) by introduced bees in Tasmania

Exotic plant invasions threaten ecological communities world-wide. Some species are limited by a lack of suitable pollinators, but the introduction of exotic pollinators can facilitate rapid spread. In Tasmania, where many non-native plants are naturalised, exotic honeybees (Apis mellifera) and bumblebees (Bombus terrestris) have become established. We determined how these species affect the pollination of Lupinus arboreus, an invasive, nitrogen-fixing shrub, which is rarely visited by native pollinators. The proportion of flowers setting seed and the number of ovules fertilised per flower were positively related to the visitation rates of both exotic bee species. There was no effect of bee visitation rates on the proportion of seeds aborted prior to maturity, possibly due to post-fertilisation environmental constraints. We conclude that the spread of B. terrestris may not alter the fecundity of L. arboreus because of the pollination service provided by A. mellifera, and discuss potential interactions between these two bee species.     

Alterations in serotonin receptor-induced contractility of bovine lateral saphenous vein in cattle grazing endophyte-infected tall fescue

As part of a 2-yr study documenting the physiologic impact of grazing endophyte-infected tall fescue on growing cattle, 2 experiments were conducted to characterize and evaluate effects of grazing 2 levels of toxic endophyte-infected tall fescue pastures on vascular contractility and serotonin receptors. Experiment 1 examined vasoconstrictive activities of 5-hydroxytryptamine (5HT), α-methylserotonin (ME5HT; a 5HT(2) receptor agonist), d-lysergic acid (LSA), and ergovaline (ERV) on lateral saphenous veins collected from steers immediately removed from a high-endophyte-infected tall fescue pasture (HE) or a low-endophyte-infected mixed-grass (LE) pasture. Using the same pastures, Exp. 2 evaluated effects of grazing 2 levels of toxic endophyte-infected tall fescue on vasoconstrictive activities of (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI), BW 723C86 (BW7), CGS-12066A (CGS), and 5-carboxamidotryptamine hemiethanolate maleate (5CT), agonists for 5HT(2A),( 2B), 5HT(1B), and 5HT(7) receptors, respectively. One-half of the steers in Exp. 2 were slaughtered immediately after removal from pasture, and the other one-half were fed finishing diets for >91 d before slaughter. For Exp. 1, maximal contractile intensities were greater (P < 0.05) for steers grazing LE pastures than HE pastures for 5HT (73.3 vs. 48.9 ± 2.1%), ME5HT (52.7 vs. 24.9 ± 1.5%), and ERV (65.7 vs. 49.1 ± 2.6%). Onset of contractile response did not differ for 5HT (P = 0.26) and ERV (P = 0.93), but onset of ME5HT contraction was not initiated (P < 0.05) in HE steers until 10(-4) compared with 10(-5) M in LE-grazing steers. For Exp. 2, maximal contractile intensities achieved with DOI were 35% less (P < 0.05), whereas those achieved with 5CT were 37% greater (P < 0.05), in steers grazing HE pastures. Contractile response to CGS did not differ between pasture groups, and there was an absence of contractile response to BW7 in both groups. There were no differences between endophyte content in contractile responses after animals were finished for >91 d. Experiment 1 demonstrated that grazing of HE pastures for 89 to 105 d induces functional alterations in blood vessels, as evidenced by reduced contractile capacity and altered serotonergic receptor activity. Experiment 2 demonstrated that grazing HE pastures alters vascular responses, which may be mediated through altered serotonin receptor activities, and these alterations may be ameliorated by the removal of ergot alkaloid exposure as demonstrated by the absence of differences in finished steers.     

Effect of chromium picolinate and chromium propionate on glucose and insulin kinetics of growing barrows and on growth and carcass traits of growing-finishing barrows

Two experiments were conducted to determine the effects of dietary Cr tripicolinate (CrPic) or Cr propionate (CrProp) on growth, carcass traits, plasma metabolites, glucose tolerance, and insulin sensitivity in pigs. In Exp. 1, 36 barrows (12 per treatment; initial and final BW were 20 and 38 kg) were allotted to the following treatments: 1) corn-soybean meal basal diet (control), 2) as 1 + 200 ppb Cr as CrPic, or 3) as 1 + 200 ppb Cr as CrProp. Growth performance data were collected for 28 d, and then 23 pigs (seven, eight, and eight pigs for treatments 1, 2, and 3, respectively) were fitted with jugular catheters and a glucose tolerance test (500 mg glucose/kg BW) and an insulin challenge test (0.1 IU of porcine insulin/kg BW) were conducted. Both CrPic and CrProp decreased (P < 0.05) ADG and ADFI but did not affect gain:feed (P > 0.10). Fasting plasma glucose, total cholesterol, urea N, insulin, and high-density lipoprotein cholesterol:total cholesterol concentrations were not affected (P > 0.10) by either Cr source. Pigs fed CrPic had lower (P < 0.02) fasting plasma NEFA concentrations than control pigs, but plasma NEFA concentrations of pigs fed CrProp were not affected (P > 0.10). During the glucose tolerance test, glucose and insulin kinetics were not affected by treatment (P > 0.10). During the insulin challenge test, glucose clearance was increased (P < 0.01) in pigs fed CrProp but not affected (P > 0.10) in pigs fed CrPic. Glucose half-life was decreased (P < 0.03) in pigs fed CrPic or CrProp, but insulin kinetics were not affected (P > 0.10). In Exp. 2, 48 barrows (four replicates of four pigs per replicate; initial and final BW were 23 and 115 kg) were allotted to the same dietary treatments in a growing-finishing study. Average daily gain, ADFI, and gain:feed were not affected (P > 0.10) by treatments. Carcass length tended (P = 0.10) to be greater in pigs fed CrPic than in pigs fed CrProp, but other carcass measurements were not affected (P > 0.10). Glucose kinetics from the insulin challenge test indicate that both CrPic and CrProp increase insulin sensitivity and that both Cr sources are bioavailable.     

Toward forest ‘‘sprawl':monitoring and planning a changing landscape for urban sustainability

The present study analyzes the structure and dynamics of the forest landscape in a peri-urban area(Rome, Italy) during the city's expansion from 1949 to2008 using landscape metrics and change detection analysis of digital maps of the area(1500 km2). While urban settlements increased continuously from 6.5 to 27.5 % of the study area, woodlands changed less clearly, with a moderate increase(from 11.2 to 11.9 % of the total area)and a higher fragmentation as a consequence of Rome's expansion. The structure of forest landscape changed along the urban-to-rural gradient with patch size increasing with the distance to the inner city in 1949 and substantial landscape homogeneity in 2008. The indicators proposed in this study inform dedicated measures for conserving forest and maintaining landscape diversity. Measures adopted in Rome's forestation plan to counteract woodlandffragmentation were analyzed and discussed. Based on the complex landscape dynamics found for Rome, an integrated multiscale planning approach targeting forest conservation is considered a key contribution to urban sustainability.     

Circulating melanin-containing cells and neutrophils with phagocytized melanin granules in a horse with disseminated melanoma

An 18-year-old, grey, Thoroughbred Cross gelding was referred to the Cummings School of Veterinary Medicine at Tufts University following a 3-week history of low-grade fever of unknown origin, distal limb swelling, and weight loss. Clinical examination identified a few black, round, smooth nodules along the ventral aspect of the proximal tail. Transabdominal ultrasound showed a markedly enlarged heterogenous spleen, hyperechoic liver nodules, and evidence of peritonitis with fibrin deposition. A mature neutrophilia was noted on complete blood count with variable numbers of phagocytized granules within neutrophils. The granules did not stain with Perl's Prussian blue, and were intensely positive when stained with Fontana-Mason, consistent with melanin. On necropsy, the spleen occupied approximately one-third of the abdominal cavity and was diffusely firm with abundant black pigment on cut section. The medullary space of the 18th thoracic vertebra was also diffusely blackened. The splenic, mediastinal, and tracheobronchial lymph nodes were five times the normal size and diffusely pigmented. The final anatomic diagnosis was disseminated malignant melanoma with extensive splenic involvement and hemolymphatic and vascular neoplastic dissemination. To the authors' knowledge, this is the first full report to identify circulating neutrophils containing phagocytized melanin granules, which confirmed an antemortem diagnosis of disseminated melanoma.     

Diagnostic procedures and surgical treatment of craniodorsal coxofemoral luxation in calves

OBJECTIVE: To report use of ultrasonographic examination of the coxofemoral joint, a surgical technique for repair of craniodorsal coxofemoral dislocation, and outcome. STUDY DESIGN: Clinical case reports. ANIMALS: Calves (n=4) with coxofemoral luxation. METHODS: Craniodorsal coxofemoral luxation was diagnosed by physical examination, radiographic, and ultrasonographic findings. Open surgical reduction of the femoral head was performed using a modified caudal approach. RESULTS: Craniodorsal luxation of the femoral head and the presence of an intact femoral neck were confirmed by ultrasonography. All luxations were successfully reduced and reluxation did not occur. At follow-up, 1 heifer had calved and 1 was 5 months pregnant. One calf died of bronchopneumonia 6 days after surgery. One calf had severe coxofemoral degenerative joint disease diagnosed (ultrasonography, radiography, and arthrocentesis) 3 months after surgery and confirmed by necropsy. CONCLUSION: Ultrasonography proved to be a simple and effective non-invasive technique for diagnosis of coxofemoral luxation. Immediate surgical intervention in hip dislocation in calves is necessary to avoid unnecessary trauma to subchondral structures. In calves, open instead of closed surgical reduction appears preferable because it allows access to the acetabular cavity for removal of debris. CLINICAL RELEVANCE: Ultrasonography should be considered a supplementary but not an alternative to radiographic examination for diagnosis of coxofemoral luxation and for follow-up examinations after reduction.     

围产奶牛饲养要点

在有效的饲养操作下,奶牛的产奶量、健康状况及繁殖性能可达到良好平衡。获得高的经济回报的关键在于上述三方面性能都能保持良好。围产期是奶牛在泌乳周期中进行泌乳和确保良好的健康、繁殖状况的一个关键契机。围产期指产犊前60天至产犊后60天。而围产期中最为关键的时间是产犊前21天至产犊后21天。围产期的饲喂及管理操作的正确性对于奶牛的干物质