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71.
Poor teat and udder structure, frequently associated with older cows, impact cow production and health as well as calf morbidity and mortality. However, producer culling, for reasons including age, production, feed availability, and beef markets, creates a bias in teat (TS) and udder scores (US) assessed and submitted to the Canadian Angus Association for genetic evaluations toward improved mammary structure. In addition, due to the infancy of the reporting program, repeated scores are rare. Prior to the adoption of genetic evaluations for TS and US in Canadian Angus cattle, it is imperative to verify that TS and US from young cows are the same traits as TS and US estimated on mature cows. Genetic parameters for TS and US from all cows (n = 4,192) and then from young cows (parities 1 and 2) and from mature cows (parity ≥ 4) were estimated using a single-trait animal model. Genetic correlations for the traits between the two cow age groups were estimated using a two-trait animal model. Estimates of heritability (posterior SD [PSD]) were 0.32 (0.07) and 0.45 (0.07) for young TS and US and 0.27 (0.07) and 0.31 (0.07) for mature TS and US, respectively. Genetic correlation (PSD) between the young and mature traits was 0.87 (0.13) for TS and 0.40 (0.17) for US. Genome-wide association studies were used to further explore the genetic and biological commonalities and differences between the two groups. Although there were no genes in common for the two USs, 12 genes overlapped for TS in the two cow age groups. Interestingly, there were also 23 genes in common between TS and US in mature cows. Based on these findings, it is recommended that producers collect TS and US on their cow herd annually.  相似文献   
72.
Some effects of dietary medicinal herbs mixture (HM), Massa medicata fermentata, Crataegi fructus, Artemisia capillaries, and Cnidium officinale, in the proportions 2∶2∶1∶1 were identified in juvenile Japanese flounder Paralichthys olivaceus. In an 8-week feeding trial, fish were fed with 0.1, 0.3, 0.5, and 1.0% HM in a moist diet composed of horse mackerel and an artificial diet in equal parts. Fish fed the diets with 0.3, 0.5, and 1.0% HM showed higher weight gain and feed efficiency than fish in 0.1 and 0% HM feed groups. No significant differences were found in survival, feed intake, final carcass proximate composition, hemoglobin and hematocrit levels, plasma total cholesterol level, and alanine aminotransferase activity among the dietary treatments. Fish fed with 0.3, 0.5, and 1.0% HM showed higher total carcass unsaturated fatty acid content and docosahexaenoic acid (22∶6n−3) level, and plasma high density lipoprotein-cholesterol level, but lower carcass saturated fatty acid content and plasma aspartate aminotrasferase activities than the control group. Moreover, a 10-min air exposure test with five times repeat, and an anesthesia test for 2 min with 200 p.p.m. 2-phenoxyethanol, also revealed lower mortality and lower recovery time in 0.3, 0.5, and 1.0% HM groups than the control group at the end of the trial. These results indicate that the medicinal herb mixture is useful to improve growth, fatty acid utilization, and stress recovery in the Japanese flounder.  相似文献   
73.
The development of feeding behaviour in two rainbow trout strains and their hybrid was compared at the transition from endogenous nutrition to exogenous feeding. After 60 min of acclimatization, the swimming pattern, spatial distribution, agonistic behaviour and snapping of fish were quantified by making 5-min observations on groups of five fish. Behavioural patterns were recorded in four replicate groups per treatment, before and after the introduction of dry trout feed or Artemia nauplii (actometric tests) or extracts of these (olfactometric tests). Fish of the slow growing strain were less active than those of the other two strains. Greater swimming activity observed in the fish of the fast growing strain was associated with more rapid feeding and a higher number of snapping responses. Such behavioural precocity is of interest because it could provide the basis for the growth differences between the fast and slow growing strains.  相似文献   
74.

Coffee beverage quality is highly correlated with the degree of fruit ripeness. In this sense, monitoring fruit ripeness is of utmost importance for harvest planning and, especially for obtaining high-quality beverages. Currently, this process is carried out through manual counts of unripe fruits, which is laborious and limited to a few plants within the field. This study aimed at evaluating the potential of a low-cost multispectral camera for coffee ripeness monitoring in the Zona da Mata region of Minas Gerais State, Brazil. For that, five fields of Arabica coffee with distinct characteristics were evaluated. During the coffee ripeness period, four flights were carried using a Phantom 4 Pro quadcopter equipped with a Mapir Survey 3W camera for imagery acquisition. After that, nine vegetation indices (VIs) were obtained. For the same dates, the percentage of unripe fruits was obtained using an irregular grid in all fields. The data was split into two ripeness classes: suitable for harvest (R) with?<?30% of unripe fruits; and not suitable for harvest (U), with?>?30% of unripe fruits. Then, a principal component analysis was used to infer the importance of the VIs to discriminate plants with unripe fruits from those with ripe fruits. The first two principal components explained?>?75% of the variance in the datasets from all coffee fields. The VIs were able to discriminate the ripeness classes (U and R) in most fields; however, their performance was directly influenced by the crop yield and canopy volume.

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75.
The influence of dicyanodiamidine sulphate (DDS) on the quality of some cereal crops was studied in several pot experiments. In each of the experiments DDS was compared with ammonium sulphate (AS) and mixtures of AS + DDS in several proportions. The experiments were carried out in several soils and the influence of soil characteristics were evident in the final results. The cereals studied were sorghum, wheat, rye, barley and fescue. Influence of different treatments was studied in relation to the composition either of whole plants, or of straw and grain separately.Application of DDS is especially important for protein content and quality of products. The utilization of this fertilizer is rather slow and continuous during the vegetative cycle of plants, and as a consequence protein synthesis is mainly increased specially in the grain. Protein quality in wheat may or may not be affected depending upon the exchange capacity of the soil. In cereals used for pasture and subjected to several cuts the influence of DDS is also important, decreasing differences in production and quality among the different cuts, particularly noticeable in the summer cuts. Mineral composition of plants is also affected by DDS.The conclusion that can be drawn is that DDS, in mixtures with AS, may be a very important tool in nitrogen fertilization mainly on light soils, long term crops and under conditions of heavy rains, circumstances where its more or less continuous utilization and resistance to leaching are important features to be considered in production and for the quality of the products.
Zusammenfassung Der Einfluß von Dicyandiamidinsulfat (DDS) auf die Qualität einiger Cerealien wurde in mehreren Gefäßversuchen untersucht. In jedem dieser Versuche verglich man DDS mit Ammoniumsulfat (AS) und mit Mischungen von AS + DDS in verschiedenen Proportionen. Die Versuche wurden in mehreren Böden durchgeführt. In den Endergebnissen kam der Einfluß der charakteristischen Bodeneigenschaften gut heraus. Die im Versuch stehenden Cerealien waren Sorghum, Weizen, Roggen, Gerste und Wiesenschwingel (Festuca). Der Einfluß der verschiedenen Behandlungen konnte durch die chemische Zusammensetzung der ganzen Pflanze oder getrennt nach Stroh und Korn verfolgt werden.Die Verabfolgung von DDS ist insbesondere für den Eiweißgehalt und für die Qualität der Erzeugnisse bedeutsam. Die Ausnutzung dieses Düngers ist während der vegetativen Entwicklung ziemlich langsam und andauernd, infolgedessen ist die Eiweißsynthese speziell im Korn besonders erhöht. Eiweißqualität kann oder kann nicht im Weizen beeinflußt werden. Dies hängt von der Austauschkapazität des Bodens ab. In Cerealien für Weidezwecke fand man bei verschiedenen Schnitten ebenfalls einen bedeutenden Einfluß von DDS. Unterschiede in Menge und Qualität zwischen den verschiedenen Schnitten wurden vermindert, insbesondere beim Sommerschnitt. Auch die Mineralstoffzusammensetzung der Pflanzen konnte durch DDS beeinflußt werden.Zusammenfassend kann gesagt werden, daß sich DDS zur Stickstoffdüngung zusammen mit AS hauptsächlich auf leichten Böden sehr nützlich erweisen kann, ebenso bei Pflanzen mit langer Vegetationszeit und bei schweren Regenfällen, also bei Bedingungen, wo es mehr oder weniger auf laufende Nährstoff-Ausnutzung und auf Verhinderung der Nährstoffauswaschung ankommt. Dies sind wichtige Fakten für die Erzeugung und für die Qualität der Produkte.

Resumé L'influence du sulfate de dicyanodimidine (SDD) dans la qualité de quelques céreales a été étudiée dans des essais en pots. Le SDD a été comparé dans tout les cas avec le sulfate d'ammonium (SA) et avec des mélanges SA+SDD.Ces essais ont été conduits sur différents types de sols et on a vérifié l'influence des caractéristiques du sol dans la production et dans la qualité des produits. Les céreales qui ont été essayés sont le sorghum, le blé, le seigle, l'orge et la fétuque. L'influence des traitements a été étudiée soit sur la composition chimique de la plante intiére soit sur la composition de la tige et du grain en séparé. Le SDD influence notamment la teneur et la qualité des protéines. On vérifie que ce produit est utilisé par les plantes d'une façon lente et continuelle tout au ling de son cycle de végétation et, en conséquence la synthèse des proteínes du grain est assez béneficiée. Dans le cas du blé on a verifié que la qualité des proteínes est diminuée ou non selon la capacité d'échange du sol. Dans les céreales utilisés comme paturage l'influence du SDD est aussi importante, en diminuant les variations de production et de la qualité parmis les différents coupes, notamment en ce qui concerne la production d'Eté. La composition minérale est aussi modifiée par le SDD.On a conclus que le SDD, en mélange avec le SA, peût constituer un important instrument de la fertilization azotée, surtout dans des sols légers, avec une pluviosité importante et dans des cultures de longue permanence dans le sol, parce que dans ces cas l'utilization plus ou moins continuelle et graduelle du SDD et sa résistance au lessivage lui permêt de représenter un rôle important dans l'amélioration de la production et de la qualité des produits.


Professor of Agricultural Chemistry. Deceased on 5th October 1975.  相似文献   
76.
AIM: To determine the effect of grazing pasture that had a low selenium (Se) concentration on serum concentrations of tri iodothyronine (T3) and thyroxine (T4), and erythrocyte glutathione peroxidase (GSH-Px) activity in dairy cows.

METHODS: Forty pregnant Friesian cows were grazed on pasture that contained 0.03–0.04 ppm Se on a dry matter (DM) basis. Two months before parturition, 20 cows were randomly selected and treated with 1 mg Se/kg bodyweight subcutaneously, as barium selenate (Group Se-S). The other group (Se-D) was not supplemented. Blood samples were taken before supplementation (-60 days) and 30, 60, 90, 180 and 270 days after parturition, for determination of concentrations of T3 and T4 in serum, and GSH-Px activity in erythrocytes.

RESULTS: Erythrocyte GSH-Px activity in the Se-D group was >60 U/g haemoglobin (Hb) throughout the experiment. Supplementation increased (p>0.05) activities to >130 U/g Hb throughout lactation. Mean serum concentrations of T4 in Se-D and Se-S cows increased from 23.7 (SEM 0.7) and 23.4 (SEM 0.8) nmol/L, respectively, in the prepartum period to 69.6 (SEM 0.1) and 67.6 (SEM 0.2) nmol/L, respectively, at 180 days of lactation (p>0.01), and no effect of Se supplementation was evident. Serum concentrations of T3 in Se-D cows decreased (p>0.05) from 1.6 (SEM 0.1) nmol/L prepartum to 1.0 (SEM 0.2) nmol/L at the beginning of lactation, and remained lower (p>0.05) than those in the Se-S cows which did not decrease after calving and ranged from 1.9 (SEM 0.1) to 2.4 (SEM 0.2) nmol/L throughout lactation.

CONCLUSIONS: Serum T3 concentrations decreased during early lactation in unsupplemented cows grazing pastures low in Se (0.03–0.04 ppm) and both serum T3 and erythrocyte GSH-Px activities were consistently lower throughout lactation compared with Se-supplemented cows. Se supplementation had no effect on serum T4 concentrations.  相似文献   
77.
Rearing blackspot seabream has been associated with low growth rates and excessive lipid accumulation, resulting in a reduction of the edible yield. The effect of extruded diets containing different carbohydrate sources (wheat vs. wheat bran) was evaluated on 100 g blackspot seabream growth performance, feed utilization and fat deposition, taking into consideration the optimal dietary protein and lipid level described for smaller‐sized fish. A fish meal‐based diet was also tested as a control to assure maximal growth rates were achieved. The experiment was held in sea cages at environmental conditions. Duplicate groups of fish were distributed among six cages with a stocking density of 1.3 kg/m3 and hand‐fed each diet for 7 months. At the end of the experiment, fish in all groups doubled their body weight attaining 190–230 g. Specific growth rate (0.3–04), feed conversion ratio (1.3–1.6) and protein gain (0.5–0.6 g/kg/day) were similar among treatments. The Hepatosomatic Index, the Viscerosomatic Index and final whole body composition did not vary significantly among dietary treatments; nevertheless, the inclusion of wheat bran induced a significant increase of liver lipid content and the highest mesenteric fat index. All diets were effective in reducing whole body and mesenteric fat compared with initial values.  相似文献   
78.
The current study aimed to determine the effects of dietary probiotic supplementation on growth, gut morphology and non‐specific immune parameters in Senegalese sole (Solea senegalensis) juveniles during a 1‐month trial. Fish were fed for 1‐month two diets with 1.0 or 4.6 × 106 CFU kg?1) of probiotic A (Bacillus sp., Pediococcus sp., Enterococcus sp. and Lactobacillus sp.) and two diets with 3.5 or 8.6 × 105 CFU kg?1 of probiotic B (Pediococcus acidilactici) and tested against an unsupplemented diet (control). Growth performance, as well as respiratory burst activity, nitric oxide (NO), alternative complement pathway (ACH50), lysozyme and peroxidase activities, was not affected by the dietary treatments. Probiotic supplementation tended to increased growth homogeneity between tanks having diet A1 the best possible alternative to decrease costs associated to size grading. Villous length and number of goblet cells of the anterior intestine did not vary among treatments. Muscle duodenal layer was significantly thicker in fish fed probiotic A compared to probiotic B, when included at the lowest level (A2 versus B2). The current study indicate that the use of the multispecies probiotic at 1.0 × 106 CFU kg?1 might enhance protection against pathogen outbreak and increase nutrient absorption, whereas at the highest concentration could reduced size dispersion among tanks.  相似文献   
79.
The aim of this study was to evaluate the use of whole-body plethysmography as a non-invasive method to determine the respiratory parameters and profiles in two tortoise species belonging to the genus Testudo. Pulmonary functions and volumetric parameters were determined in 10 adults of Testudo hermanni and in seven Testudo marginata animals, using whole-body plethysmography. A profile pattern was regularly observed: an inspiratory flow peak, an expiratory peak, an apnoea phase and a second expiratory peak, previous to the beginning of the next respiratory cycle. Positive and significant correlation was observed between the inspiratory time, weight and length of the tortoises. Larger tortoises showed a higher time of inhalation. The peak of inspiratory flow was correlated with the sex, being longer in the females. T. marginata had an inspiratory time longer than that of T. hermanii. In T. hermanii, differences related to the sex were observed in the tidal volume, peak inspiratory flow, peak expiratory flow, expiratory flow of 50 per cent and enhanced pause, which could be related to the smaller size of males. The results suggest that additional information on new technologies currently used in pet medicine or even in human medicine should be developed and adjusted as alternative ways to support the rehabilitation of turtles and tortoises.  相似文献   
80.
In cats, accuracy of parturition day prediction by ultrasonographic measurement of foetal structures is decreasing towards the end of gestation. Foetal measurements during the last days of pregnancy are scarce. We determined foetal biparietal, abdominal and eye diameter (BPD, AD and ED, respectively) by ultrasonography as well as maternal blood progesterone (P4) within five days of delivery to predict parturition date and calculate accuracy of prediction. Foetal BPD at birth was compared with newborn kitten head diameter (HD). Kitten HD, crown‐rump length (CRL) and body weight were compared by breed and gender. Ultrasonography measurements were carried out on the day of parturition in 14 queens, and on days 62–63 after the first mating and repeated 24–72 hr later in ten other cats. Accuracy of parturition day prediction using BPD and AD was determined based on the equations of Beccaglia et al. (2008) Veterinary Research Communications, 32(Suppl 1), S99 and Garcia Mitacek et al. (2015) Theriogenology, 84, 1131. Progesterone was measured at the time of presentation and repeated 24–72 hr later if parturition did not occur. Data were analysed with linear regression, t test, Mann–Whitney U test, one‐way anova and Kruskal–Wallis test. There was a moderate relationship between BPD, days before birth (DBB) and litter size. AD and DBB had a low agreement, and ED was not associated with DBB. BPD at birth was significantly related to HD. The accuracy of parturition day prediction using BPD and AD was 27–53% and 17–35%, respectively. Kitten HD was associated with body weight, and both were inversely related to litter size. Newborn biometric measurements differed by breed but not by gender. Progesterone decreased towards parturition and reached 3.18 ± 1.68 ng/ml on the day of delivery. In conclusion, close to birth, the combination of foetal ultrasonography and maternal blood P4 rather than each as a sole predictor of parturition is recommended.  相似文献   
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