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1.
J Environ Qual ; 41(2): 420-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22370404

RESUMEN

Permanent grass vegetation on sloping soils is an option to protect fields from erosion, but decaying grass may liberate considerable amounts of dissolved reactive P (DRP) in springtime runoff. We studied the effects of freezing and thawing of grassed soil on surface runoff P concentrations by indoor rainfall simulations and tested whether the peak P concentrations could be reduced by amending the soil with P-binding materials containing Ca or Fe. Forty grass-vegetated soil blocks (surface area 0.045 m, depth 0.07 m) were retrieved from two permanent buffer zones on a clay and loam soil in southwest Finland. Four replicates were amended with either: (i) gypsum from phosphoric acid processing (CaSO × 2HO, 6 t ha), (ii) chalk powder (CaCO, 3.3 t ha), (iii) Fe-gypsum (6 t ha) from TiO processing, or (iv) granulated ferric sulfate (Fe[SO], 0.7 t ha), with four replicates serving as untreated controls. Rainfall (3.3 h × 5 mm h) was applied on presaturated samples set at a slope of 5% and the surface runoff was analyzed for DRP, total dissolved P (TDP), total P (TP), and suspended solids. Rainfall simulation was repeated twice after the samples were frozen. Freezing and thawing of the samples increased the surface runoff DRP concentration of the control treatment from 0.19 to 0.46 mg L, up to 2.6-3.7 mg L, with DRP being the main P form in surface runoff. Compared with the controls, surface runoff from soils amended with Fe compounds had 57 to 80% and 47 to 72% lower concentrations of DRP and TP, respectively, but the gypsum and chalk powder did not affect the P concentrations. Thus, amendments containing Fe might be an option to improve DRP retention in, e.g., buffer zones.


Asunto(s)
Fósforo/análisis , Poaceae , Lluvia/química , Estaciones del Año , Suelo/química , Carbonato de Calcio/química , Sulfato de Calcio/química , Compuestos Férricos/química , Congelación , Laboratorios , Titanio/química
2.
J Dairy Sci ; 91(6): 2342-52, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18487656

RESUMEN

Understanding optimal replacement practices is essential in milk production management. In this study, we produced a stochastic dynamic optimization model that included the risk of diseases. Moreover, the study took into consideration the genetic production capacity of a cow and the uncertainty related to it. We determined the optimal replacement policy separately for Ayrshire and for Holstein-Friesian Finnish herds. The need for veterinary treatments and the probability of involuntary culling were estimated from the Finnish dairy herd health recording system. We found that the portion of involuntary culling was approximately 50% of present disposals. The need for veterinary treatments and the probability of involuntary culling were higher for Holstein-Friesian than for Ayrshire cows. Regardless of health status, only the oldest cows with low production capacity should be disposed of intentionally. In the postoptimization steady state, the mean parity was 3.8 and 3.7 for Ayrshire and Holstein-Friesian herds, respectively. Under current management practice, the mean is only 2.3 parities. Preventing premature culling of dairy cows is important to improve the possibilities of breeding selection and the economic performance of milk production. The expected net present value of a cow was slightly higher in Ayrshire than in Holstein-Friesian herds. The results indicate that in the long run, it is worth paying attention to the health status and longevity of a cow as well as to its high yield.


Asunto(s)
Cruzamiento , Enfermedades de los Bovinos/economía , Bovinos/fisiología , Industria Lechera/economía , Estado de Salud , Lactancia/fisiología , Factores de Edad , Animales , Bovinos/genética , Enfermedades de los Bovinos/genética , Enfermedades de los Bovinos/mortalidad , Femenino , Finlandia , Predisposición Genética a la Enfermedad , Lactancia/genética , Longevidad , Paridad , Embarazo , Factores de Riesgo , Procesos Estocásticos
3.
J Nutr Health Aging ; 21(5): 492-500, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28448078

RESUMEN

OBJECTIVE: To study differences in consumption of foods and intake of nutrients attributable to denture status. DESIGN, SETTING AND PARTICIPANTS: Data from a cross-sectional, nationally representative Health 2000 Survey, subjects aged 55-84 years (n=2,241). MEASUREMENTS: Denture status (edentulous with full dentures, own dentition with removable dentures, own dentition with no removable dentures) was used as an explanatory variable. The consumption of foods and intake of nutrients was used as an outcome variable and was measured using a validated Food Frequency Questionnaire. RESULTS: Denture status associated with food choices. Full denture wearers consumed less vegetables (p = 0.013 among men and p = 0.001 among women) and fruits (p = 0.001 among women), more sugary products (p = 0.012 among men and p = 0.008 among women), and their balance in fatty acids was less favourable than among dentate participants. Among dentate participants, the differences between the two groups were small and statistically significant differences were seen mostly in women. CONCLUSIONS: Wearing full dentures appears to be associated with unhealthier food choices, lower consumption of some foodstuffs and lower intake of certain nutrients when compared to the food choices of dentate persons.


Asunto(s)
Dentición , Dentaduras , Ingestión de Energía , Preferencias Alimentarias , Anciano , Estudios Transversales , Dentadura Completa , Encuestas sobre Dietas , Azúcares de la Dieta/administración & dosificación , Ácidos Grasos/administración & dosificación , Femenino , Frutas , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Verduras
4.
Physiol Behav ; 69(4-5): 571-80, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10913798

RESUMEN

Welfare-related physiological and behavioural responses were studied in farm-bred male blue foxes (Alopex lagopus). Three different-sized cages (80-cm long [CL80], 120-cm long [CL120], and 240-cm long [CL240]; each 105-cm wide x 70-cm high) with wire-mesh floors and one enlarged cage (CL240E) with both wire-mesh floor (240-cm long x 105-cm wide x 70-cm high) and earthen floor (80-cm long x 105-cm wide x 70-cm high) were compared. N = 30 males for each group. The experiments lasted from weaning in July to pelting in December. Statistical analyses were based on the models accounting for litter as a block effect. Breaking strength of tibia was highest for foxes having access to both wire-mesh and ground floors (CL240E). Stress-induced hyperthermia was evident during capture and immobilisation. The highest rectal temperature (mean +/- SEM) was found in CL240E (capture: 39.6 +/- 0.09 degrees C, restraint:40.0 +/- 0.09 degrees C) and the lowest in CL80 (capture: 39.1 +/- 0.09 degrees C, restraint: 39.7 +/- 0.09 degrees C). Likewise, capture time (median; interquartile range) in the home cage was highest in CL240E (29; 18 to 44) and lowest in CL80 (12; 9 to 14). During capture, foxes tended to withdraw to the farthest site within the cage. CL240E foxes typically showed the most fear towards human. The most confident animals were found in CL80. The cortisol:creatinine ratio (median; interquartile range) obtained from circadian urine did not reveal statistically significant differences among CL80 (3. 5; 2.6 to 4.1), CL120 (2.3; 1.5 to 3.8) and CL240 (2.3, 1.5 to 3.7). The earthen flooring complicated the urine sampling and conclusions for CL240E (1.7; 1.2 to 2.2). CL240E foxes were the most active and explorative on both wire-mesh- and ground-floored open-field arenas. Altogether, 53% of furs from CL240E were classified as very dirty. Dirtiness of furs in other test groups was slight. In conclusion, the present results did not reveal an unambiguous superiority of any of the studied cage options for well-being of farmed blue foxes.


Asunto(s)
Conducta Animal/fisiología , Ambiente , Zorros/fisiología , Vivienda para Animales , Espacio Personal , Crianza de Animales Domésticos , Animales , Temperatura Corporal/fisiología , Peso Corporal/fisiología , Ingestión de Alimentos/fisiología , Cabello/fisiología , Hematócrito , Hígado/crecimiento & desarrollo , Masculino , Tamaño de los Órganos/fisiología , Timo/crecimiento & desarrollo , Tibia/crecimiento & desarrollo , Tibia/fisiología
5.
Small Rumin Res ; 39(1): 47-57, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11163715

RESUMEN

A comparison of conserving timothy/meadow fescue/meadow grass as silage or hay was conducted with Finnish Landrace ewes. Intake of hay (H), silage (S) and hay/silage (HS), and the performance of 30 Finnish Landrace ewes carrying twins, triplets and quadruplets and suckling either twin or triplet lambs was measured during the last 8 weeks of pregnancy and during the first 6 weeks of lactation. The dry matter (DM) intake of HS was lower (p<0.03) than H during lactation, whereas there was no difference in DM intake between pregnant and lactating ewes fed either H or S. The intake of metabolisable energy was on an average 12.8, 14.3 and 13.4MJperday in pregnancy, and 17.7, 20.2 and 18.1MJ in lactation for H, S and HS, respectively. Daily intakes of protein assessed in terms of amino acids absorbed in the small intestine (AAT) were on an average 92, 110 and 102g for H, S and HS during pregnancy and 157, 184 and 165g during lactation, respectively. Ewes in all treatments were, relative to calculated requirements, deficient in energy and protein during the last month of pregnancy and early lactation. Ewes performed consistently better when fed silage than hay. Lamb mortality was low for all treatments. The number of artificially reared lambs tended to be highest when ewes were fed both hay and silage ad libitum. Lamb growth was higher on S than H based diet (p<0.005). With respect to winter feeding of ewes, grass silage compared favourably with hay and indicated that hay could be replaced by well preserved grass silage. During late pregnancy and early lactation, there was no advantage of supplementing silage with hay, relative to entirely silage based diets.

6.
J Agric Sci ; 150(2): 145-160, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22505777

RESUMEN

Global climate change is predicted to shift seasonal temperature and precipitation patterns. An increasing frequency of extreme weather events such as heat waves and prolonged droughts is predicted, but there are high levels of uncertainty about the nature of local changes. Crop adaptation will be important in reducing potential damage to agriculture. Crop diversity may enhance resilience to climate variability and changes that are difficult to predict. Therefore, there has to be sufficient diversity within the set of available cultivars in response to weather parameters critical for yield formation. To determine the scale of such 'weather response diversity' within barley (Hordeum vulgare L.), an important crop in northern conditions, the yield responses of a wide range of modern and historical varieties were analysed according to a well-defined set of critical agro-meteorological variables. The Finnish long-term dataset of MTT Official Variety Trials was used together with historical weather records of the Finnish Meteorological Institute. The foci of the analysis were firstly to describe the general response of barley to different weather conditions and secondly to reveal the diversity among varieties in the sensitivity to each weather variable. It was established that barley yields were frequently reduced by drought or excessive rain early in the season, by high temperatures at around heading, and by accelerated temperature sum accumulation rates during periods 2 weeks before heading and between heading and yellow ripeness. Low temperatures early in the season increased yields, but frost during the first 4 weeks after sowing had no effect. After canopy establishment, higher precipitation on average resulted in higher yields. In a cultivar-specific analysis, it was found that there were differences in responses to all but three of the studied climatic variables: waterlogging and drought early in the season and temperature sum accumulation rate before heading. The results suggest that low temperatures early in the season, delayed sowing, rain 3-7 weeks after sowing, a temperature change 3-4 weeks after sowing, a high temperature sum accumulation rate from heading to yellow ripeness and high temperatures (⩾25°C) at around heading could mostly be addressed by exploiting the traits found in the range of varieties included in the present study. However, new technology and novel genetic material are needed to enable crops to withstand periods of excessive rain or drought early in the season and to enhance performance under increased temperature sum accumulation rates prior to heading.

7.
Animal ; 5(3): 428-32, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22445409

RESUMEN

We developed a method for studying the synchrony of behaviour based on calculations of overdispersion of a binomial process. The lying behaviour of cows was investigated under two different housing units inside the same barn. The first unit housed 30 cows undergoing conventional milking and the second unit housed 27 cows undergoing automatic milking. The lying behaviour of the cows was observed over 3 weeks in 12 periods of 6 h each. Every 5 min, we counted the number of cows lying down in the cubicles. As external cues, like feeding and conventional milking, can promote synchrony in dairy cows, we expected that cows conventionally milked would show more behavioural synchrony than automatically milked cows. Cows lied down synchronously in both units (overdispersion 1.67, P < 0.01). Lying synchrony tended to be slightly bigger in automatically than in conventionally milked cows (overdispersion 1.76 v. 1.58, P = 0.09), although the proportion of cows lying down was on average greater in conventionally than in automatically milked cows (60.7% v. 45.6%). This suggests that synchronized lying behaviour in cows is a constant phenomenon that depends on social facilitation rather than on external cues. The overdispersion index appears to be a useful tool for studying the synchrony of animal behaviour when observations are made at the group level.

8.
Biol Reprod ; 65(1): 52-9, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11420222

RESUMEN

The aim of the present study was to find a reliable functional criterion for the evaluation of the proliferation potential of bovine in vitro-produced embryos. We used immunocytochemical detection of proliferating cell nuclear antigen (PCNA) combined with propidium iodide (PI) staining and subsequent confocal laser scanning microscopy together with routine morphological evaluation under a stereomicroscope to study fresh Day 7, 8, and 9, and cryopreserved Day 7 and 8 embryos. The ratio of PCNA/PI-positive nuclei was equal in fresh Day 7 and Day 8 embryos and significantly lower in Day 9 embryos. In general, Day 7 embryos tolerated the cryopreservation treatments better than Day 8 embryos. Vitrification in normal straws was especially detrimental to Day 8 embryos. In fresh Day 7 and 8 embryos, the PCNA results were in agreement with stereomicroscopic evaluation. However, in Day 9 fresh and in Day 7 and 8 treated embryos, the missing PCNA revealed disorders that were not observed under morphological evaluation. PCNA immunocytochemistry is an effective method to obtain information about the functional state of nuclei. The ratio of PCNA-positive nuclei can provide more information and numerical data about the developmental potential of bovine embryos after cryopreservation.


Asunto(s)
Embrión de Mamíferos/citología , Desarrollo Embrionario y Fetal/fisiología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Animales , Bovinos , Recuento de Células , División Celular , Núcleo Celular/ultraestructura , Colorantes , Criopreservación , Femenino , Inmunohistoquímica , Microscopía Confocal , Embarazo , Propidio
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