Prediction of Genetic Gain in Sweet Corn using Selection Indexes

Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of...     

Crude protein in low‐fish meal diets for juvenile Litopenaeus vannamei can be reduced through a well‐balanced supplementation of essential amino acids

The use of supplemental essential amino acids (EAAs) has been shown to provide an opportunity to minimize excess levels of crude protein (CP) in animal feeds. The present study investigated the effect of reducing the amount of CP in low‐fish meal diets (5%) for juvenile Litopenaeus vannamei. Four sets of diets were prepared containing (% on a fed basis, mean ± SD) 31.24 ± 0.71, 33.70 ± 0.41, 36.90 ± 0.44, and 39.63 ± 0.14% CP, with each protein level containing a total dietary methionine (Met) (Met + Cys) level of 0.56 ± 0.02 (1.07 ± 0.23), 0.71 ± 0.01 (1.22 ± 0.20), 0.88 ± 0.02 (1.38 ± 0.22), or 1.04 ± 0.02% (1.55 ± 0.18%). Shrimp of 1.00 ± 0.08 g were stocked in 84 outdoor tanks of 1 m³ at a rate of 100 shrimp/m² and raised for 75 days. Final survival ranged from 83 to 97% and was unaffected by Met content. Both survival and yield were significantly depressed when shrimp were fed the 31% CP diet. Shrimp grew at a weekly rate of between 0.79 and 0.97 g, achieving a final body weight (BW) in excess of 10.8 g. There was a significant interaction between CP and Met over BW. Shrimp fed 0.56% Met achieved the lowest BW at harvest. Increasing CP beyond 34% did not enhance BW. With a dietary Met content of 0.71%, the highest BW was achieved with 34% CP compared to other levels. There was a significant improvement in Feed Conversion Ratio (FCR) when CP was raised from 31 to 34%. Similarly, dietary Met levels above 0.71% resulted in a significantly better FCR compared to 0.56%. Our study has shown that, if dietary Met (Met + Cys) meets a minimum of 0.71% (1.22%), levels of CP could be reduced from 40 to 34% without adverse effects on shrimp performance.     

Does the application of silvicultural management models drive the growth and stem quality of sweet chestnut coppices towards sustainability?

New Forests - The coppice is a very flexible cultural system producing several calibers adapting to the demands of the market. Small-caliber roundwood from sweet chestnut (Castanea sativa Mill.)...     

Feed preference and growth response of juvenile Litopenaeus vannamei to supplementation of marine chemoattractants in a fishmeal‐challenged diet

This study compared the feed preference and growth response of Litopenaeus vannamei to chemoattractants. A diet with 3% fishmeal was supplemented with either 3% salmon meal (POS), 3% soy protein concentrate (NEG), 3% krill meal (KRM), 3% squid meal (SQM), 3% shrimp head meal (SHM), 3% shrimp meal (SM), 3% squid liver meal (SLM), or 5% liquid sardine hydrolysate (SAH). Shrimp with a body weight (BW) of 0.99 ± 0.08 g were stocked at 100 animals/m² in 56 tanks of 1 m³ and fed 10 times daily for 74 days. Feed preference was evaluated by feeding shrimp of 10.87 ± 1.82 g in excess twice a day for 10 days in two separate feeding trays allocated in 50 tanks of 0.5 m³. Survival reached 93.3 ± 5.80% and was unaffected by supplementation. Final BW was the highest for shrimp fed the KRM‐supplemented diet (11.97 ± 0.93 g), followed by POS (11.11 ± 0.77 g) and SQM (11.01 ± 1.17 g). Diets SHM, SM, SLM, and NEG showed a lower shrimp BW than POS, but were not statistically different among them. Shrimp fed the SAH diet achieved the lowest BW (10.06 ± 1.02 g). The highest gained yield was obtained with diets KRM and POS. No statistical difference was observed in shrimp yield among other diets. The lowest feed conversion ratio (FCR) was achieved with shrimp fed KRM (1.31 ± 0.05) when compared to diets SHM (1.47 ± 0.05), SAH (1.47 ± 0.07), and SLM (1.45 ± 0.17). Two‐by‐two comparisons indicated that shrimp preferred SHM and KRM, except when these were compared to SQM and SLM. No difference in feed preference was found between diets with SQM and SLM. SAH was the least preferred raw material in all comparisons. Results indicated that KRM acts as a powerful feeding effector and growth enhancer in fishmeal‐challenged diets for whiteleg shrimp. A dietary supplementation with 3% KRM is more effective than the same dose of any other chemoattractant evaluated.     

Canine squamous cell carcinoma: Electrochemotherapy association with surgery and correlation with overall survival

Squamous cell carcinoma (SCC) is an important malignancy in dogs, due to its incidence and clinical presentation, which can be of locally aggressive single or multiple lesions with a metastatic potential. The objective of this investigation was to evaluate SCC response to treatment, anatomopathological and immunohistochemical characteristics, disease-free interval and overall survival time. 54 dogs with histopathologically diagnosed SCC were included in this study. Their mean age was 9.16 years with a range of 1–14 years. Of the 54 animals in the study, 34 (65.4%) had white skin and white fur coats. There was a significant correlation between fur coat colour and the development of tumours in areas of sun exposure (p = .001). Animals with tumours in areas of the body exposed to the sun had longer overall survival time than animals with tumours in areas not associated with sun exposure (p = .001). Surgery combined with electrochemotherapy (ECT) yielded a survival rate 32% higher than using a surgical approach alone (HR = 0.32, p = .038, IC = 0.11–0.94). ECT, with or without surgery, had an objective response rate of 90.9%. Local lymph node and/or distant site metastasis at diagnosis, or at some point during follow-up, occurred in 34.6% (18/52) of animals. Animals with tumours in sun exposed locations had more aggressive histopathological characteristics but had longer overall survival time. This is probably due to individualised therapeutic treatment with both surgery and ECT.     

Milk production,intake, digestion,blood parameters,and ingestive behavior of cows supplemented with by-products from the biodiesel industry

This study aimed to evaluate the intake, digestion, blood parameters, and feeding behavior of crossbred dairy cows (Holstein?×?Gir) managed on Panicum maximum Jacq. cv. Tanzania-1 and provided supplementation with groundnut cake, sunflower cake, or palm kernel cake (to replace soybean meal). Sixteen cows were randomly assigned in a Latin square design with four treatments and four experimental periods. The consumption of nutrients from the pasture did not vary between experimental treatments. Cows receiving the palm kernel cake supplement had a reduced crude protein, non-fibrous carbohydrate, and total digestible nutrient intake and an increase in the average consumption of ether extract. There was also a reduction in the digestibility of dry matter. The inclusion of supplements in the diet did not influence the average time spent eating, ruminating, or resting. The mean values of respiratory and heart rates showed thermal comfort during the trial period. There was a reduction in blood urea nitrogen with palm kernel cake supplementation, and the values of total protein, albumin, and glucose were also significantly different with this supplement. It is recommended that cakes of groundnut cake and sunflower cake seed be used for a total replacement of soybean meal supplements for lactating cows, but the use of palm kernel cake is not recommended.

     

Comparison of selection methods among and within full-sibling progenies in Urochloa humidicola

Hybridization in the Urochloa humidicola breeding programme allowed to explore the genetic variability of the apomictic sources and, thus, to obtain new sexual and apomictic parents with compatible ploidy and/or superior progenies. However, given the high variability arising from crosses, there is a need to adopt efficient selection strategies among and within progenies. The aim of this study was to compare the selection methods among U. humidicola progenies with (t-BLUP) and without (BLUP) the weighting based on prediction error and subsequent selection within progenies by individual simulated (BLUP_IS) or optimal individual BLUP. We evaluated seventy-one U. humidicola full-sib progenies from biparental crosses between nine sexual and ten apomictic parents. The experiment was set up in an incomplete block design with 64 blocks of 15 plots each, consisting of individual plants. Seven consecutive cuts were made and the traits total dry-matter, leaf dry-matter and regrowth scores were measured. Genetic variance was expressive for all traits. The selection procedure among progenies of U. humidicula based on t-BLUP proved to be more advantageous regarding the use of BLUP not weighted by the prediction error, resulting in higher selection gains, taking as reference the optimal procedure of the individual BLUP. Furthermore, the use of BLUP_IS allowed an optimized selection of hybrids, allowing the breeder to explore with variable selection intensity the genetic variability within the selected full-sib progenies based on relative genetic merit.     

Ultrasound-Assisted Extraction for the Recovery of Carotenoids from Guava’s Pulp and Waste Powders

Plant Foods for Human Nutrition - In this work, lycopene- and β-carotene-rich extracts were obtained from guava’s pulp and waste powders using maceration (ME), ultrasonic bath (BUAE,...     

Anabolism,catabolism and proteomic analysis in the slow‐twitch muscle of pacu (Piaractus mesopotamicus) submitted to prolonged fasting followed by refeeding

Here, we aimed to study the slow muscle of the fish Piaractus mesopotamicus submitted to 30 days of fasting (D30) followed by 1 day (D31) or 30 days of refeeding (D60). Histological analysis of fibre diameter was performed in D30 and D60. The gene expression of parvalbumin (pvalb), atrogenes (murf1a, murf1b, mafbx) and anabolic genes (igf‐1, mtor) was analysed using RT‐qPCR in D30, D31 and D60. The proteome was obtained by shotgun proteomics at D30 and D60, and the set of differentially expressed proteins was analysed by bioinformatics. In all experiments, the control was regularly fed fish. The histological analysis showed no changes in muscle fibre diameter. The expression of catabolic and anabolic genes was not changed, except for the downregulation of igf‐1 in D30 and of mafbx in D31. The expression of pvalb was not changed in D30 and D60 but was decreased in D31. The proteomic analysis identified 169 proteins in D30 (24 upregulated and 18 downregulated) and 170 proteins in D60 (17 upregulated and 21 downregulated); many of them were related to energetic metabolism and intracellular Ca²⁺ homoeostasis. Overall, our results indicate that the slow‐twitch muscle presented few changes upon prolonged fasting and refeeding condition.     

Meta-analysis of fungicide efficacy on soybean target spot and cost–benefit assessment

Target spot of soybean has spread in Brazil, the southeastern United States and Argentina in the last decade. A collaborative network of field Uniform Fungicide Trials (UFT) in Brazil was created in 2011 to study the target spot control efficacy of fungicides, including azoxystrobin + benzovindiflupyr (AZ_BF), carbendazim (CZM), fluxapyroxad + pyraclostrobin (FLUX_PYRA), epoxiconazole + FLUX_PYRA (EPO_FLUX_PYRA), mancozeb (MZB) and prothioconazole + trifloxystrobin (PROT_TRIF). Network meta-analysis was used to conduct a quantitative synthesis of UFT data collected from 2012 to 2016 and to evaluate the effects of disease pressure (DP, low ≤ 35% target spot severity in the nontreated control < high) and year of experiment on the overall mean efficacy and yield response to each of the tested fungicides. Based on mean percentage control of target spot severity, the tested fungicides fall into three efficacy groups (EG): high EG, FLUX_PYRA (76.2% control relative to the nontreated control) and EPO_FLUX_PYRA (75.7% control); intermediate EG, PROT_TRIF (66.5% control) and low EG, MZB (49.6% control), AZ_BF (46.7% control) and CZM (32.4% control). DP had a significant effect on yield response. At DP_Low, the highest response was due to PROT_TRIF (+342 kg ha⁻¹, +12.8%) and EPO_FLUX_PYRA (+295.5 kg ha⁻¹, +11.2%), whereas at DP_High, EPO_FLUX_PYRA and FLUX_PYRA outperformed the other treatments, with yield responses of 503 kg ha⁻¹ (+20.2%) and 469 kg ha⁻¹ (+19.1%), respectively. The probability of a positive return on fungicide investment ranged from 0.26 to 0.56 at DP_Low and from 0.34 to 0.66 at DP_High.