Spanish Journal of Agricultural Research
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Body growth and phenotypic variation of the carcasses of native duck lineages (Cairina moschata)
No full textNatives ducks are birds that require little handling and are resistant to many diseases that affect chickens. Thus, they adapt to low-input farming conditions, which contributes to the food security of small farmers. Although they exhibit potential for growth, their production characteristics are relatively unknown, so they are underexploited. The objective of this study was to compare how nonlinear models fit the growth curve of two genetic groups of duck and to evaluate variation based on carcass characteristics. Two hundred and twenty four animals were weighed weekly, from birth to 90 days of age. We used nonlinear models (Brody, Richards, Gompertz, Von Bertalanff and Logistic) to describe growth curve. For the evaluation of phenotypic variation, we measured seven carcass traits from 81 ducks carried out by principal component analysis. The logistic model best fit the growth curve, and the absolute growth rates (AGR) for the Catolé duck showed that females reached their maximum AGR at approximately 30 days but did not reach their ideal commercial weight. The drumstick, thigh and liver yields accounted for 41.17% of the differences between the Catolé and Paysandu ducks. The slaughter of male Catolé ducks is recommended between 70 and 90 days because a drastic decrease in growth occurs after this time. For the slaughter of females, feeding management modifications and improvement in growth indices are recommended to increase the final weight and AGR. The carcass yields indicate potential for native duck meat production
Growth and nutrients content of Atriplex canescens across a soil electric conductivity gradient
No full textAtriplex canescens canopy cover, biomass production, and nutrient content were evaluated after four years of livestock grazing exclusion and mechanical shrub removal, except A. canescensin an arid rangeland with a slightly saline soil and with a long history of heavy livestock grazing in the southern Chihuahuan Desert, Mexico (24° N). Twenty 3 × 3 m paddocks were established in terrains with three levels of electric conductivity (EC): <1.4 dS/m (n=7), 1.4–1.6 dS/m (n=7) and >1.6 dS/m. Atriplex canescens canopy cover was higher (49.5%; p<0.01) on paddocks with soil EC >1.6 dS/m than paddocks with soil EC <1.4 and 1.4–1.6 dS/m (32.1 and 22.9%, respectively). Above-ground biomass did not differ between paddocks with soils with EC of <1.4 and 1.4–1.6 dS/m (1309 ± 535 and 1372 ± 180 kg DM/ha), but biomass increased 2.7 times (p<0.01) when soil EC was greater than 1.6 dS/m. The soil EC had no effect on the levels of crude protein (range 13.6 to 14.3%), neutral detergent fiber (range 56.5 to 57.7%) and ash (range 14.5 to 16.4%). In vitro dry matter digestibility (IVDMD) of the foliage of A. canescens was not affected by of soil EC level (range 60.4 to 62.2%). It was concluded that in an arid rangeland with slight saline soil, the increase in salinity favors canopy cover and biomass production of A. canescens without altering nutrient content and IVDMD of this fodder shrub
Short communication: Identification and relationship of the autochthonous ‘Romé’ and ‘Rome Tinto’ grapevine cultivars
No full textThe ‘Romé’ variety is considered an Andalusian (southern region in Spain) autochthonous black grape cultivar. However, several white and black grapevine accessions are known by this name, according to Vitis International Variety Catalogue. The aim of the present work was to clarify the identity of the ‘Romé’ and ‘Rome Tinto’ as black grapevine cultivar. Eight accessions known as ‘Romé’ and two as ‘Rome Tinto’ were analyzed using 30 OIV descriptors and 22 SSR loci. The morphologic and genetic analysis showed that all accessions studied presented the same genotype and phenotype and grouped with South Spanish cultivars. This study helps to clarify the confusion over the identity of ‘Romé’ grapevine cultivar, and provides a solid basis to develop a germplasm collection to protect grapevine diversity and to recover cultivars that may be in danger of extinction
Analysis of the commercial value of rabbit meat based on positioning of the different types of fresh meat
No full textIn-depth knowledge of consumers' perceptions of value is considered a critical success factor in today’s competitive market. There is very little information about the perception that consumers have of rabbit meat compared to other types of meat (mainly beef and pork). To identify the consumer perception of rabbit meat in Spain, two marketing tools were used: positioning and image analysis. To this end, a survey was carried out in Spain mainland with an error of 3.53% and a confidence level of 95.5%. According to the positioning analysis, rabbit meat competed with turkey for the "low fat" and "healthy" attributes. Rabbit meat had in its favour that it was considered more “economical” than turkey. Commercially, rabbit meat did not compete with any other fresh meat and it was not associated with any other adjective. The image that consumers had of rabbit meat was that it is a clean, healthy and easy to find meat. Two clearly distinguished groups were also found: consumers who rated rabbit meat more positively and consumers that did so less positively. These two groups were defined by the variables “educational level”, “rabbit meat consumption by children under 18 residing in the home”, “geographical area” and “habitual residence”. For the variables “gender”, “age”, “number of people in the home” and “presence of children younger than 18 years in the home”, there were no significant differences. These results are very useful for the different value chain stakeholders, who can set different marketing strategies to improve rabbit meat consumption
Valuation of nutritional and health claims for yoghurts in Spain: A hedonic price approach
No full textThis article investigates price effects of nutritional claims (NC) and health claims (HC), in addition to other attributes, on yoghurts in the Spanish market. Prices and product characteristics are collected from yoghurt label references found on the shelves of the main representative retail shops in the capital city of Aragon (Zaragoza) Spain. The total sample included 508 yoghurts. Nutritional and health claims (NHCs) are selected based on the official definitions of the (EC) Regulation No 1924/2006 and No 432/2012. Premium prices of the NHCs and other attributes included were assessed through a hedonic price approach. Results show that yoghurt is a highly differentiated food product. NCs related to fat-free, low in sugar and fiber content did not affect yoghurt prices while most of the health claims received significant positive effects. Health claims outperform nutritional claims leading to higher premium prices. These findings are a useful source in a better understanding of the evolution of NHCs in the Spanish market. Our findings suggest that NCs accompanied by the corresponding HC, which exactly defines the benefits of that nutrient in our health may be a promising strategy for product differentiation
Short communication: Broadening the diagnosis panel of reproductive pathogens associated with abortion in ruminants
No full textDiagnosis of abortion in cattle, sheep and goat have been mainly focused on abortive pathogens with a recognized impact in outbreaks, but the aetiologic diagnosis rates have been historically low worldwide. Thus, we analysed the presence of pathogens in abortion outbreaks, focusing on the less-common pathogens in cattle farms with control programmes for reproductive pathogens, and in ovine and caprine farms. Thirty-one cases from Galician farms submitted to our laboratory during 2013-2015 were analysed (16 bovine, 7 ovine and 8 caprine farms) by polymerase chain reaction and culture from foetal tissues (n = 52 foetuses). Diagnosis was reached in 21/31 farms: 9/16 in bovine, 6/7 in ovine and 6/8 in caprine. Campylobacter spp. were found in all three species (3/9 diagnosed cases in bovine, 2/6 in ovine and 4/6 in caprine). Furthermore, Ureaplasma diversum was detected in cattle (4/9 of diagnosed cases), Bovine Viral Diarrhoea Virus – 2 was detected in sheep (2/6) and Neospora caninum in goats (1/6). Our results prove the occurrence of abortion in response to pathogens that are traditionally considered less relevant and rarely included in the diagnosis of ruminant abortion. Therefore, differential diagnosis of abortion should consider these pathogens (at least when other causes have been ruled out), to effectively control abortion in farms
Olive fruit detachment force against pulling and torsional stress
No full textOlive harvesting often requires high hand labour, considering that workers, with long poles or hand held devices, aid trunk shaker due to low harvesting efficiency. Currently, fruit detachment force (FDF) and fruit fresh weight were used to predict harvesting efficiency, although during harvesting process, fruit is subjected to bending and twisting movement besides pulling forces simulated by FDF measurements. For these reasons, the aim of the present study was to determine FDF evolution under different stalk twisting angles. In order to provide more information about mechanical behaviour of olive stalk, a trial was carried out during ripening process on four olive (Olea europaea L.) cultivars: Frantoio, Arbequina, Leccino and Maurino. FDF under traction force was measured after applying different stalk twisting angles (0°, 90°, 180°, 270°, 360°, 540°, 720º). FDF was considered to be 0 when fruit was detached from the bearing branch during the twisting process. Fruit weight, firmness, ripeness index and oil content were also measured to determine the optimal period for olive harvesting and olive ripening stage at each sampling date. FDF was significantly reduced, usually over 180º, when stalk was rotated before applying the pull force to measure FDF, keeping differences along fruit ripening process. Moreover, stalk twisting was an important variable for olive detachment, considering that fruits detached without pulling forces varied between 10.7 and 58.8% of the total fruits according with the different sampling dates. For these reasons, present and future harvesting systems, should take advantage of stalk susceptibility against torsion or bending strain to increase harvesting efficiency
Leaf cuticular wax content is involved in cotton leaf curl virus disease resistance in cotton (Gossypium hirsutum L.)
No full textCotton leaf curl virus disease (CLCuVD) limits cotton production in many cotton growing countries of the world, including Pakistan. In the past, efforts were made to combat this disease by different approaches. Cuticular wax is reported to confer resistance to plants against various biotic and abiotic stresses. Present study was designed to assess the role of cuticular wax content (WC) to resist CLCuVD infestation. The WC of 42 cotton genotypes, originating from various countries (Pakistan, USA, China, etc.), was quantified during two culture periods (2015 & 2016). Cotton germplasm was also scored for % disease index (%DI), seed cotton yield (SCY), number of bolls/plant (NB), and plant height (PHt) for the same culture periods. Significant negative correlation between WC and %DI was found during the two years of experimentation. WC was found positively correlated with SCY and NB. Six cotton genotypes (A-7233, B-557, A-162, BLANCO-3363, CIM-473, and SLH-2010-11) did not show any signs of CLCuVD infestation during both 2015 and 2016. These cotton genotypes contained relatively higher WC. The results from analysis of variance (ANOVA) demonstrated that there were significant differences among genotypes for %DI, WC, SCY, NB, and PHt. These results indicated that WC was involved in resisting CLCuVD and it also had positive effect on plant growth and yield potential. On the basis of these findings, it was concluded that cuticular wax could be used as an indirect criterion for distinguishing and selecting resistant/susceptible cotton genotypes
Short communication: Concentrate supplementation strategies in ryegrass pasture for productive performance in lambs
No full textThis study evaluated the effect of two concentrate supplementation strategies on performance, metabolic profile and economic evaluation of suckling lambs and ewes in ryegrass (Lolium multiflorum) pasture. Twenty-seven ewes and 45 lambs were divided into three groups: (1) ryegrass pasture without supplementation - control (CON); (2) CON plus supplemented ewes and lambs at 1% of live weight (SEL), and (3) CON plus creep feeding supplemented lambs at 1% of live weight (CSL). Concentrate use increased (p<0.05) average daily gain (ADG) by 19.95% over CON (21.6 and 18.3% for SEL and CSL, respectively). Concentrate use contributed to minimizing forage quality fluctuation and provided greater ADG stability, mainly when ryegrass nutritional content and digestibility decreased. Blood metabolites profiles did not differ between groups, with exception of phosphorus which was higher for CON than SEL, and calcium which was higher for CSL than CON (p<0.05). Compared to CON, stoking rate values were greater to SEL (p<0.05). Compared to CSL, ewe and total stocking rate were greater (p<0.05) to SEL. Considering the control group as break even feed investment, SEL strategy had a positive economic return, while CSL showed economic losses. Concentrate use increased ADG of lambs and decrease the impact of nutrient quality changes of forage on daily gains, but must be considered that supplemental strategy used could affect negatively economic return
An automatic and non-intrusive hybrid computer vision system for the estimation of peel thickness in Thomson orange
No full textOrange peel has important flavor and nutrition properties and is often used for making jam and oil in the food industry. For previous reasons, oranges with high peel thickness are valuable. In order to properly estimate peel thickness in Thomson orange fruit, based on a number of relevant image features (area, eccentricity, perimeter, length/area, blue component, green component, red component, width, contrast, texture, width/area, width/length, roughness, and length) a novel automatic and non-intrusive approach based on computer vision with a hybrid particle swarm optimization (PSO), genetic algorithm (GA) and artificial neural network (ANN) system is proposed. Three features (width/area, width/length and length/area ratios) were selected as inputs to the system. A total of 100 oranges were used, performing cross validation with 100 repeated experiments with uniform random samples test sets. Taguchi’s robust optimization technique was applied to determine the optimal set of parameters. Prediction results for orange peel thickness (mm) based on the levels that were achieved by Taguchi’s method were evaluated in several ways, including orange peel thickness true-estimated boxplots for the 100 orange database and various error parameters: the sum square error (SSE), the mean absolute error (MAE), the coefficient of determination (R2), the root mean square error (RMSE), and the mean square error (MSE), resulting in mean error parameter values of R2=0.854±0.052, MSE=0.038±0.010, and MAE=0.159±0.023, over the test set, which to our best knowledge are remarkable numbers for an automatic and non-intrusive approach with potential application to real-time orange peel thickness estimation in the food industry