Spanish Journal of Agricultural Research
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Changes in the content of edible and non-edible components and distribution of tissue components in cockerels and capons
No full textThe aim of this study was to determine the effects of castration and age on the content of edible and non-edible components, and the distribution of tissue components in the carcasses of cockerels and capons. The study was conducted on 200 birds (Green-legged Partridge), divided into two sex categories (with 5 replications per group and 20 birds per replication), raised to 28 wk of age. At 8 wk of age, 100 birds were surgically castrated and afterwards at 12 wk of age and at four-wk intervals, 10 intact cockerels and 10 capons were selected randomly and slaughtered. Cockerels, compared with capons, were characterized by a higher proportion of edible components at 24 and 28 wk of age, and a more desirable carcass tissue composition due to a higher content of lean meat in total body weight (BW). Capons had higher abdominal fat content than cockerels, which resulted in a higher percentage of non-edible components in their BW at 24 and 28 wk of age. Differences in the distribution of lean meat in the carcass were noted from 20 wk of age in both castrated and intact birds. The content of breast muscles increased in capons, and the content of leg muscles (thigh and drumstick) increased in cockerels. The results of this study indicate that in view of the optimal lean meat content of the carcass and the optimal distribution of major tissue components, Green-legged Partridge capons should be fattened for a maximum period of 24 wk
Internationalization and performance in agri-food firms
No full textThis paper studies the relationship between internationalization and performance in agri-food firms. In line with the recent literature, it analyses the effects of the degree of internationalization using a uniform sample, a long-term focus and a measure that combines export intensity and regional diversification. The study empirically confirms the hypothesis of a horizontal S-curve relationship between geographical diversification and performance and identifies three phases. Export firms are found in the first phase; their profits are low due the initial costs incurred in exporting. Companies with a more advanced internationalization process are in the second phase; they benefit from the positive outcomes of operating on a larger scale. Lastly, the third phase contains highly international, geographically diversified companies; their performance decreases as a result of the costs of entering extra-regional markets, which are especially steep in this sector; they also face higher transition costs and organisational complexity. The results presented could be interesting for policymakers designing and implementing export programmes for agri-food firms. Policies should include assistance at the start of the internationalization process and an attempt to prolong the strategy until the volume of business is sufficient to start showing an increase in performance. The policies could possibly promote networking between Spanish and foreign companies to reduce the costs of more global internationalization strategies
Eigenvector index for two female fertility traits based in random regression coefficients matrix in Holstein cows
No full textA total of 71,518 days open (DO) and number of services per conception (NSC) records of 28,523 Iranian Holstein cows were analysed by random regression model. Akaike’s information criterion and likelihood ratio test suggested that a model with quadratic Legendre polynomials for additive genetic and permanent environmental was best. Heritability in different parities ranged from 0.103 to 0.045 in first parity and 0.054 to 0.030 in sixth parity for DO and NSC, respectively. Estimated genetic correlations between parities decreased continuously with increasing distance between parities for both DO and NSC. The first eigenfunction explained 89.99% and 97.22 % of the total genetic variance of DO and NSC, while the second eigenfunction accounted 6.24% and 3.18%, respectively. Different selection indices were constructed for DO and NSC. Genetic response to improve overall fertility was greater when the index included the first eigenvector than the response obtained from indices excluding it. Similar genetic gains were obtained from the first eigenvector, which had a nearly flat associated eigenfunction along lactations and from selection by the intercept of the random regression. The first eigenvector indices were responsible of changes in the level of DO and NSC in a similar manner for all parities, without altering the shape of the response curve across parities. The second and third eigenvector indices modified the shape of this curve but the improvement in genetic gains by including them in the selection index were small (DO) or negligible (NSC) due to the small amount of variability associated with these components
Antifungal effects of phenolic extract from industrial residues of Aloe vera
No full textThis research is concerned with the fungicidal properties of the phenolic extract from industrial residues of Aloe vera used for antifungal treatment of various plant pathogens (Fusarium oxysporum f. sp. radicis-lycopersici, Phaeomoniella chlamydospora, Phaeoacremonium aleophilum, and Sporisorium scitamineum). Six phenolic compounds were identified in this extract from A. vera cortex: aloesin, α-barbaloin, chromone X, isoaloeresin D, β- barbaloin and aloeresin E. Phenolic extract was added to PDA medium at 20 concentrations from 0.32% to 10% and the growth of four different plant pathogenic fungi was tested. Fungal inhibition was calculated in order to evaluate the antifungal efficacy of phenolic extract against pathogens. Inhibition of Sporisorium scitamineum hyphal growth was observed after treatment with the phenolic extract at concentrations higher than 2.5% and a fungistatic effect with a 58.2% mycelia growth inhibition was detected at 3% extract concentration. Inhibition of P. chlamydospora and P. aleophilum hyphal growth was observed at concentrations higher than 4% and 3% respectively. A fungistatic effect with a 71.65% and a 19.87% mycelia growth inhibition was detected at 4.5% and 3.5% extract concentration respectively. About F. oxysporum f. sp. radicis-lycopersici, inhibition of hyphal growth was observed at concentrations higher than 2.5% and a fungistatic effect with a 32.07% mycelia growth inhibition was detected at 3% extract concentration. The results indicate that the tested extract possess antifungal activities against these pathogens at various concentration levels and could be used as a potential natural fungicide in order to control fungi pathogens providing a new use for the A. vera industrial residues
Alleviation of heat-stress-related physiological perturbations in growing rabbits using natural antioxidants
No full textThe current study was performed to evaluate the effects of the dietary inclusion of extra virgin olive oil (EVOO), betaine (BET), lemongrass essential oil (LGEO), gallic acid (GA), vitamin C (VC) and vitamin E (VE) on different body temperature traits and stress hormone and glucose levels in heat-stressed growing rabbits. Rabbits were fed diets with no supplementation (control group) or supplemented with 15 g of EVOO, 400 mg of LGEO, 500 mg of GA, 1000 mg of BET, 500 mg of VC, or 200 mg of VE per kg of diet. All tested feed additives, especially EVOO, had a lowering effect on various rabbit temperature traits. Both triiodothyronine (T3) and tetraiodothyronine/thyroxine (T4) were increased (p<0.05) by the addition of BET, VC, EVOO, and VE. With the exception of the VC group, all dietary groups showed no significant changes in the insulin level compared to the control group level. In contrast, the cortisol and glucose levels were diminished (p<0.05) in all treated groups compared to the control levels. The results suggested that all tested supplementations had positive ameliorating effects on growing rabbits under a severe heat load in terms of lowered body temperatures and a favourable stress hormone balance, with the most favourable results found in the EVOO, VC, and BET supplementation groups
Nile tilapia fingerling cultivated in a low-salinity biofloc system at different stocking densities
No full textA 42-day trial was conducted to evaluate the effects of a low-salinity biofloc system with different stocking densities on water quality and zootechnical performance of Nile tilapia fingerlings (10 g/L). Four treatments were tested at different densities: 500 fish/m³, 750 fish/m³, 1,000 fish/m³ and 1,250 fish/m³, all in triplicate. Fingerlings of Oreochromis niloticus (initial mean weight of 1.17 ± 0.05 g) were stocked in twelve experimental black-plastic tanks (40 L) with no water exchange during the experimental period. Molasses was added daily to the system at 30% of the amount of feed, and fish were given four daily rations of a formulated feed composed of 36% crude protein and 9% lipids. Water quality variables (dissolved oxygen, pH, salinity, TAN, NO2, NO3 and PO43) did not demonstrate significant differences between the treatments. However, significant influences (α ≤ 0.05) of the stocking densities were observed for total suspended solids, settleable solids, final weight, yield, and protein efficiency ratio. The results showed survival over 96%, final weight values between 12 and 18 g, yield between 9.49 and 15.27 kg/m3, water consumption of 52 to 101 L/kg fish, and total time of settling chambers between 238 and 305 h/kg fish. These results indicate a negative effect of stocking density on final weight, survival, alkalinity, NO2, PO43 and water consumption, and a positive effect on yield in Nile tilapia fingerling culture (1-20 g) in a low-salinity biofloc system with densities up to 1000 fish/m³
The effect of coarse-droplet spraying with double flat fan air induction nozzle and spray volume adjustment model on the efficiency of fungicides and residues in processing tomato
No full textThe study was conducted for the purpose of improving the application of fungicides against potato late blight (Phytophthora infestans (Mont.) de Bary) (PLB) in processing tomato. The usability of coarse spray quality with double flat fan air induction IDKT12003 nozzle and the impact of fixed and variable spray volume and adjuvants during alternate application of azoxystrobin and chlorothalonil were analysed on the basis of plant infestation and fungicide residues. The variable spray volume was calculated based on the number of leaves on a plant. The study was conducted during three vegetation seasons. Spraying of plants with significantly flattened canopies during the peak of the fructification season using an IDKT12003 nozzle was as effective as in the case of fine spraying performed with an XR11003 nozzle and facilitated the increase of fungicides residue. In the case of plants with high-spreading canopy at the beginning of fructification, XR11003 nozzle favoured the reduction of PLB infestation. Both spray volume adjustment systems enabled the same level of protection of tomato against PLB, which could result from alternate application of systemic and contact fungicides. Polyalkyleneoxide modified heptamethyltrisiloxane adjuvant, which causes siginificant increase in wetting and droplet spreading, facilitated the reduction of tomato PLB infestation during the application of fungicides using an IDKT12003 nozzle
Statistical methods for identifying anisotropy in the Spodoptera frugiperda spatial distribution
No full textCorn is a very important agricultural product, however, some pests may cause damage to the corn productivity such as Spodoptera frugiperda, which prevents the plant from growing in a regular manner. Since the indiscriminate use of the pesticide may cause an increasing resistance of the insect besides an environmental damage, it is important to estimate the areas and the dominant directions where the insect may propagate. The main aim of this work was to study the spreading of the fall armyworm in a commercial agricultural area in the South of Brazil. For this, we considered a set including the location of each corn plant attacked by the insect. In particular, we assumed that the spatial locations given by the geographic coordinates constitute a spatial point pattern following a stationary Poisson point process. In order to detect the presence of possible dominant directions in the distribution of the fall armyworm infestation we studied the anisotropic features of the data by using some second-order spatial point-pattern analysis techniques such as the K directional test, the wavelet-based test, and the quadrat counting test. All the results showed that spatial distribution of fall armyworm may follow a clustered Poisson point process with the presence of an evident anisotropy mainly due to the shape and the distance between corn plants of the experimental area. These preliminary results could be used for reducing and optimizing the use of pesticides with a consequent decrease of the environmental impact
Pig’s behavioral response in nursery and growth phases to environmental enrichment objects
No full textThe objective of this research was to evaluate the effect of environmental enrichment on the behavior of pigs in nursery and growth phases. (i) Ninety animals (females, 65 days, 25 kg) were divided into three treatments (T1- Pen enriched with objects made of destructible material by the animal, T2- Pen enriched with objects made of non-destructible material by the animal, T3- Pen without environmental enrichment objects - control treatment) - in a completely randomized design and reference of the animals by objects of enrichment of different colors (red, blue or yellow). (ii) males, 25 days old, 7 kg were distributed in a completely randomized design with four treatments (cloves, garlic, alternating aromas and absence of control smells) and six replicates each. (iii) determine the appropriate ratio between the number of enrichment objects and the animals present in the animals (n = 138; females; 65 days; 25 kg) were distributed in three treatments, in a completely randomized experimental design (proportion of one enrichment object for each 1511 animals or 9 animals, respectively). Environmental enrichment objects made from destructible materials are more attractive to pigs. No preference for pigs for environmental enrichment objects of specific colors was observed. Environmental enrichment objects with garlic aroma had a repellent effect. No effect was observed of alternating perfumes in the animals retaining interest in the objects since the smell of garlic acted as a repellent. Thus, the proportion of one enrichment object for each 15 pigs is sufficient to avoid problems of dispute between the animals
Genetic variability assessment in ‘Muscat’ grapevines including ‘Muscat of Alexandria’ clones from selection programs
No full textGenetic variability is needed to face environmental changes and pathogen constrains. In addition, the search for intravarietal variability contributes to the avoidance of genetic erosion, preserving clones that are adapted to particular conditions. Variability is also important to diversify grapevine-derived products. In this work, we have analyzed the genetic variability of ‘Muscat germplasm’ including samples from neglected vineyards from Alicante and Valencia provinces, accessions of the germplasm collections of ‘Colección de Vides de El Encín’ (Alcalá de Henares, Madrid) and ‘La Casa de las Vides’ (Agullent, Valencia), accessions supplied by nurseries of Valencia province, and ‘Muscat of Alexandria’ clones selected using differential ampelographic characteristics in selection programs (La Marina, Alicante). Fifteen microsatellites (SSRs) were used to study intervarietal variability. The SSR fingerprinting allowed the identification of some accessions, variants, and synonymies. Amplified Fragment Length Polymorphisms (AFLPs) markers and Microsatellite-AFLPs were used to determine the variability attended in ‘Muscat of Alexandria’ accessions. A CAPs (Cleaved Amplified Polymorphic Sequences) marker, recently developed for the discrimination of ‘Muscat’ flavor genotypes using the SNP1822 G>T, was assessed and showed that all the analyzed accessions were ‘Muscat’ flavored. The variation found among the analyzed germplasm is very interesting because variants within ‘Muscat of Alexandria’, ‘Muscat Italia’, and ‘Muscat d’Istambul’ have been identified. In addition, intravarietal genetic variation was found among the analyzed accessions in ‘Muscat of Alexandria’ from selection programs