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981.
982.
This study aimed to evaluate the effects of replacement of soybean meal (SBM) with soybean meal treated with tannin (SBMT) on the intake, digestibility, performance and characteristics of the carcasses of young cattle fed a high‐concentrate diet. Forty‐two Nellore bulls with body weight of 244.5 ± 4.99 kg were used. Diets had the inclusion of 7.5% SBM, with a proportion of that SBM (0, 33, 66 or 100%) replaced for SBMT; and other treatment (SBMT + urea) just with 2.5% of SBM which was treated with tannins. Seven animals were randomly selected and slaughtered, and the remaining animals were distributed on treatments and remained for 112 days. After, all animals were slaughtered. There was a linear decline in dry matter intake (P = 0.026) when SBM was replaced with SBMT. No decrease in carcass weight (P > 0.05) was observed. The efficiency of carcass weight gain showed a quadratic function effect (P = 0.049). There were changes in carcass gain composition when SBMT was added (P < 0.05), with an increase in muscle and reduction in fat deposition. The use of SBMT in place of SBM causes changes in body gain composition in animals and reduces DM intake by the animals, achieving a better feed conversion efficiency.  相似文献   
983.

Context

Agricultural intensification is a leading cause of landscape homogenization, with negative consequences for biodiversity and ecosystem services. Conserving or promoting heterogeneity requires a detailed understanding of how farm management affects, and is affected by, landscape characteristics.

Objectives

We assessed relationships between farming systems and landscape characteristics, hypothesising that less-intensive systems act as landscape takers, by adapting management to landscape constraints, whereas more intensive systems act as landscape makers, by changing the landscape to suit farming needs.

Methods

We mapped dominant farming systems in a region of southern Portugal: traditional cereal-grazed fallow rotations; specialization on annual crops; and specialization on either cattle or sheep. We estimated landscape metrics in 241 1-km2 buffers representing the farming systems, and analysed variation among and within systems using multivariate statistics and beta diversity metrics.

Results

Landscape composition varied among systems, with dominance by either annual crops (Crop system) or pastures (Sheep), or a mixture between the two (Traditional and Cattle). There was a marked regional gradient of local landscape heterogeneity, but this contributed little to variation among systems. Landscape beta diversity declined from the Sheep to the Crop system, and it was inversely related to agriculture intensity.

Conclusions

Less intensive farming systems appeared compatible with a range of landscape characteristics (landscape takers), and may thus be particularly suited to agri-environmental management. More intensive systems appeared less flexible in terms of landscape characteristics (landscape makers), likely promoting regional homogenization. Farming systems may provide a useful standpoint to address the design of agri-environment schemes.
  相似文献   
984.
The aim of this study was to evaluate the effect of supplementation of pig diets in the growth and termination phases with different calcium sources. In experiment I, 36 whole males were distributed in randomized blocks in six groups, with six replications. A basal diet was formulated to meet the animals’ nutritional requirements except for calcium (0.09%), and the sources evaluated (calcitic limestone, monodicalcium phosphate, calcinated bone flour, and oyster flour) replaced the basal diet to provide 0.59% of total calcium. To determine the endogenous calcium, a diet containing low calcium (0.019%) was given simultaneously to another group of animals. Feces and urine were collected for determination the coefficients of apparent and true digestibility. In experiment II, 160 piglets were distributed in randomized blocks in four treatments, with five replications and four animals per experimental unit. Carcass and performance parameters, calcium concentration in bone and serum, and bone parameters were evaluated. The data were submitted to analysis of variance and factorial. The calcium source did not influence the digestibility coefficients determined by total collection (P > 0.05). The digestibility of Ca from oyster flour estimated by collection with an indicator was higher than that from the other sources (P < 0.05). Calcium sources did not interfere in the evaluated parameters (P > 0.05). The sources studied in this work can be used to supplement growing pigs’ diets.  相似文献   
985.
Evaluating phenotypic diversity makes it possible to identify discrepancies in aptitudes among animals of different genetic bases, which is an indicator of adaptive or selective differences between populations. The objective of this work was to evaluate the morphofunctional diversity of 452 male and female adult equines (Arabian, Quarter Mile, Pantaneiro, and Criollo breeds, and undefined crossbreeds of horses and mules) raised in the Pantanal biome (Brazil). Linear measurements were performed to estimate conformation indexes. Initially, a discriminant analysis was performed, regardless of the animal’s size, followed by factor analysis. The factors were characterized and used as new variables. The diversity among equines and their relationship with the factors were evaluated using multivariate analysis. The factors were classified according to their decreasing importance: balance, rusticity, and robustness for the measurement factors; and load, ability, conformation, and equilibrium for the index factors. The genetic groups of equines have well-defined morphofunctional characteristics. The main differences are based on the rusticity and ability typologies in relation to those based on performance. Equines introduced to the Pantanal biome presented a more robust and compact body with good conformation. As a result, these horses may have superior athletic performance during equestrian activities when compared to the Pantaneiro local breed. However, this biotype may represent less rusticity (less adaptive capacity). Therefore, the regional breed can be equal or better in equestrian activities than breeds introduced to the Pantanal biome. Thus, breeders may cross horses from local breeds as an alternative to those introduced. Undefined crossbred male equines presented a different profile from the Pantaneiro breed, which may indicate little use of crossbreeds in breeding.  相似文献   
986.
This study aims to evaluate the effect of the Tifton 85 hay (Cynodon dactylon L. Pers) replacement by Orelha de Elefante Mexicana spineless cactus (Opuntia stricta [Haw.] Haw) on the nutrient intake and digestibility, growth performance, microbial protein synthesis, and efficiency of dietary nitrogen compound utilization in the diets of Girolando heifers. Twenty-four (3.5 months and 100 kg ± 3.5 kg) Girolando heifers (5/8 Holstein x Gyr) were used and arranged in a completely randomized design. Dry matter, organic matter, crude protein, and neutral detergent fiber decreased linearly as a function of the levels of Tifton hay (TH) replacement by Orelha de Elefante Mexicana spineless cactus (OEM). The non-fiber carbohydrate intake and coefficient of dry matter digestibility increased, while the neutral detergent fiber (NDF) digestibility decreased linearly with the OEM inclusion. After evaluating the growth performance by observing weight gain and morphometric measurements, there were no significant alterations. The urinary volume, nitrogen balance as well as the efficiency of nitrogen retention had increased, while the urinary and plasma urea concentrations had decreased linearly with the OEM inclusion. The results obtained in this study show that Orelha de Elefante Mexicana spineless cactus should replace Tifton hay in post-weaned heifer diets.  相似文献   
987.
This aim of this study was to evaluate the intake and apparent digestibility of nutrients, ingestive behavior, blood parameters, and performance of lambs fed two roughage:concentrate (R:C) ratios, with or without liquid residue of cassava (LRC). Forty lambs (19.5?±?1.45 kg body weight) were distributed in a completely randomized 2?×?2 factorial design. The intake of dry matter (1311 g/day) and total digestible nutrients (755 g/day), and the intake (172 g/day) and digestibility (552 g/kg) of crude protein were higher for lambs fed R:C of 40:60. The R:C ratio of 80:20 promoted a higher intake (585 g/day) and digestibility (461 g/kg) of neutral detergent fiber. There was an intake of LRC of 1.37 L/day for lambs fed R:C of 80:20 and 0.42 L/day for lambs fed R:C of 40:60. The lambs fed R:C of 80:20 spent more time in feeding (326 m/day) and rumination (530 m/day). The metabolic profile and performance of lambs were not affected by LRC inclusion. The body weight gain (220 g/day) was higher in lambs fed R:C of 40:60. A roughage:concentrate ratio of 40:60 is recommended for lambs because it resulted in the best performance, regardless of supplementation with liquid residue of cassava.  相似文献   
988.
Tropical Animal Health and Production - Although prevalent, the exact impact of infectious diseases on reproductive failures remains to be determined. Among them, leptospirosis has commonly been...  相似文献   
989.
This study was conducted to evaluate the fermentation pattern and the in situ dry matter degradability of silages in the form of diet. Five diets were formulated based on spineless cactus (Opuntia fícus-indica cv. ‘Gigante’) and buffelgrass (Cenchrus ciliaris). The experimental design was completely randomised, with five treatments and three replicates in which the diets differed in the proportion of buffelgrass (0%, 15%, 25%, 30% and 35%, on a fresh matter basis). There was significant difference (p < 0.05) in the chemical composition of the diets, with all dry matter contents being within the ideal range. Ammonia-nitrogen content was not affected (p > 0.05). There were significant differences (p < 0.05) in dry matter recovery across diets, which ranged from 96.28% to 99.93%. The pH values decreased as the time of opening (days) was extended. Organic acid contents differed across all diets; however, overall, all diets showed satisfactory lactic acid contents. As the proportion of buffelgrass in the diets was increased, the degradability of dry matter decreased. Based on fermentation profile, losses and chemical composition the diet with higher proportion of spineless cactus can be recommended for silage production.  相似文献   
990.
Tropical Animal Health and Production - Subclinical hypocalcemia is a metabolic disorder characterised by a decrease in serum calcium (Ca) levels, with no clinical symptoms. The aim of this study...  相似文献   
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