RESUMO

The quality of poultry by-product meal (PBM) is not standardized in the industry. Several factors are detrimental to PBM and compromise its nutritional value and shelf life. Therefore, this study was conducted to determine the main PBM production factors that directly affect its in vitro organic matter digestibility (IVDOM) and protein oxidation (POX). Data on the processing of PBM samples (n = 100) were recorded in a rendering plant. Two types of PBM were used: 1) Low ash (LA, n = 66) with mineral matter (MM) content of 11% and 2) High ash (HA, n = 34) with MM above 11%. Processing traits and chemical composition of PBM were considered independent variables. The IVDOM and POX were determined in each sample and considered dependent variables. Data on independent variables were submitted to factorial and principal components (PC) analyses. In vitro organic matter digestibility data were clustered (P = 0.001) in low (778.92 g/kg), average (822.85 g/kg), and high (890.06 g/kg). The best arrangement was composed of six independent variables distributed in two PC, which explained 82.10% of the total variation. The ash concentration, oil to raw material ratio, collagen, and crude protein comprised PC1 with greater relevance and explained 58.46% of the total variance. The PC2 was composed of the processing time and temperature and explained 23.64% of the total variance. Protein oxidation data were clustered (P < 0.001) in low (265.19 nmol/mg CP), average (393.07 nmol/mg CP), and high (524.40 nmol/mg CP). Based on our results, the composition of the raw material from the slaughterhouse holds most of the information on PBM composition and digestibility. Developing improvements in the slaughtering or in the screening of the raw material that will be used by the rendering process is important to obtain a more nutritionally standardized ingredient.

Assuntos

RESUMO

The study aimed to measure variations in industrial process and nutritional variables of poultry by-product meal (PBM) in rendering plants from batch cookers. A total of 200 samples of low ash PBM with mineral matter (MM) content of 11% (LA, n = 104) or high ash with MM above 11% (HA, n = 96) were collected from 5 industrial processing plants. The highest coefficients of variation in chemical composition were for MM (LA - 19.70%; HA - 19.59%), ether extract (LA - 20.72%; HA - 14.86%), collagen (LA - 21.16%; HA - 30.00%) and water activity (LA - 24.54%; HA - 25.89%). However, the crude protein (LA - 5.07%; HA - 7.39%), dry matter (LA - 1.75%; HA - 2.90%) and organic matter digestibility (LA - 4.81%; HA - 6.78%) were lower. The variability of the data related to the process of PBM was: maximum process temperature (LA - 3.91%; HA - 3.56%), average process temperature (LA - 3.73%; HA - 4.71%), and processing time (LA - 27.37%; HA - 37.59%). This study evidenced that the corrective measures by limiting the amount of bones in the raw material, optimizing the pressing step for the poultry fat extraction, and also controlling the processing time of PBM may favor the production of more standardized PBM in terms of chemical composition and quality.

Assuntos

RESUMO

The aim of this study were (1) to characterize the growth curve in male and female cats, (2) to associate the growth and metabolizable energy intake (MEI) as an indirect measurement of the energy requirements, and (3) to determine the short-term effects of neutering on energy intake to maintain the bodyweight in young adult cats. Eighteen 5-months-old mixed breed cats were used in this study (males, n = 7 and BW = 2.2 ± 0.21 kg; females, n = 11 and BW = 2.0 ± 0.16 kg). The cats were fed to supply their metabolizable energy requirement for growth, adjusting the amounts to maintain an ideal body condition score. The animals were weighed every 15 days for 10 months (from 5 to 15 months old). At 12 months old, the cats were gonadectomized and the MEI was recorded for 3 months, up to 15 months old. Second-order, Gaussian, and spherical models were fitted to growth data. Male cats had higher energy intake for growth (MEI = 176.27-0.037t, R2 = 0.79) than females (MEI = 166.86-0.044t, R2 = 0.62), where t is the age in months. Male cats also reached mature weight later than female cats (16 and 13 months old, respectively). Neutering reduced the energy requirements of male (intact - 116.43 kcal/kg0.67; gonadectomized - 98.65 kcal/kg0.67; P < .01) and female cats (intact - 98.65 kcal/kg0.67; gonadectomized - 76.16 kcal/kg0.67; P < .01) on average 17.6%. This study suggests that in cats, males and females present different energy requirements since the early growth phases and, this difference remains after neutering in young adults. Female cats reach adult weight earlier than males.

Assuntos

RESUMO

The present study aimed to evaluate the inflammatory response, oxidative status and fatty acid deposition in reproductive tissues of cats supplemented with the dried microalgae Schizochytrium spp. (Thraustochytriaceae) as a DHA source. Thirty-seven cats (males, n 21; females, n 16; 11·5 (sd 0·5) months of age) were divided by sex into five groups. Treatment diets contained algae biomass at 4·0, 8·0, 12·0 or 16·0 g/kg replacing poultry fat (n-6 source). Cats were fed the respective diet for 62 d and neutered on day 58. Blood samples were collected at the beginning of the experiment (day 1), before neutering (day 58) and 4 d after surgery (day 62) for analysis of inflammation and oxidative markers. Acute-phase protein levels were altered (P < 0·01) in the postoperative period, without any treatment effect (P > 0·05). PGE2 concentrations after surgery were reduced linearly (R2 0·8706; P = 0·002) with microalgal inclusion. Blood platelet count was reduced (P = 0·001) after the surgery regardless treatment, but it was higher in the DHA group compared with control (P < 0·001). The DHA deposition (testicles, R2 0·846; ovaries, R2 0·869) and the n-6:n-3 ratio (testicles, R2 0·859; ovaries, R2 0·955) in gonads had a pattern which fitted a quadratic model. DHA from Schizochytrium spp. modifies PGE2 response after the surgery in cats. The physiological roles of the DHA in the reproduction of cats were not investigated, but its gonadal deposition after supplementation was observed.

Assuntos

RESUMO

Grooming is a natural hygienic behaviour of cats that favours the formation of hairballs. Increased fibre concentration in the diets is a strategy to minimize hairball formation, but it is not fully effective. Because cat hair is formed mostly by keratin, the addition of keratinases in the diets might be an alternative for hairball control. Thus, the objective was to evaluate the effect of the combined use of sugarcane fibre and a protease complex to reduce the hairball excretion in cats. Twenty-four adult cats were divided into four treatment groups (n = 6 per treatment) in a 2 × 2 factorial arrangement. Treatments were as follows: control diet (Control; containing low concentration of insoluble fibre, 5.34% of total dietary fibre), control diet plus enzyme (Co-e), high-fibre diet (HF; containing high amounts of insoluble fibre, 17.8% of total dietary fibre), and HF diet plus enzyme (HF-e). Proteases from Bacillus licheniformis PWD-1 were administered orally (5 mg/day) as gastro-resistant capsules. Total collection of faeces was carried out to determine the number of excreted hairballs and the coefficient of total tract apparent digestibilities (CTTAD) of the diets. Separate addition of insoluble fibre (HF; p = .5947) or enzyme complex (Co-e; p = .3633) had no effect on the hairballs excreted in the faeces. However, the combined use of insoluble fibre and enzymes (HF-e) reduced (p = .0344) the total number of hairballs excreted. The size distribution of hairballs (small, medium, or large) was not affected by treatments (p = .3763). The CTTAD of crude protein was not affected by protease addition (p = .781) but was reduced by HF and HF-e treatments. Sugarcane fibre associated to keratinolytic enzymes reduces the hairball excretion in cats. This strategy can be adopted for this purpose; however, methods for faecal hairball quantification must be improved. If you have not already completed a Copyright Transfer Agreement, please log on to Wiley Author Serivices, https://authorservices.wiley.com/bauthor/, sign-in and complete the License Agreement form".

Assuntos

RESUMO

The biomass productivity and nutrient composition of microalgae, such as Chlorella vulgaris, depend on the cultivation process and the nutrient content of growth media. Thus, in this study aimed to investigate the biomass productivity of C. vulgaris cultivated in fish and dairy cattle wastewaters. Thirty wastewater samples (2.5 L) were collected from system of production. Microalgae were cultivated in Erlenmeyer flasks containing 10 mL of microalgae and 1,790 mL of wastewater under constant light of 5,000 lux for 16 days at 25 ± 2.0 °C. Wastewater samples differed in composition. Biomass productivity was 47 % higher (P < 0.0001) in dairy cattle than in fish wastewater, reaching 67.61 g m−3 day−1 (dry matter basis, DM) when compared by Student's t-test (P < 0.05). Cultivation media also had an effect on biomass chemical composition. The C. vulgaris grown in dairy cattle wastewater was higher in crude protein and ash contents (359.6 g kg−1 DM and 230.4 g kg−1 DM, respectively), whereas microalgae grown in fish wastewater had higher nitrogen-free extract content (347.8 g kg−1 DM). Crude fat content did not vary greatly (mean of 313.15 g kg−1 DM). The pH (8.0 ­ 8.7) and ammonia concentration (0.07 to 0.4 mg L−1) in fish wastewater was stable throughout the 16-day experimental period. In dairy wastewater, pH increased up (6.3 to 8.9) to the fourth day and remained constant thereafter, and ammonia concentration increased up (24.3 to 28.7 mg L−1) to the eighth day and then it declined (2.1 mg L−1). The C. vulgaris was successfully grown in both wastewaters, but productivity was higher in dairy cattle wastewater(AU)

A produtividade e a composição de nutrientes da biomassa oriunda de microalgas, como Chlorella vulgaris, dependem do processo de cultivo e do teor de nutrientes dos meios de crescimento. Assim, este estudo teve como objetivo investigar a produtividade de biomassa de C. vulgaris cultivada em águas residuais da criação de peixes e de gado leiteiro. Trinta amostras (2.5 L) foram coletadas dos sistemas de produção. As microalgas foram cultivadas em frascos de Erlenmeyer contendo 10 mL de microalgas e 1,790 mL de águas residuais sob luz constante de 5,000 lux por 16 dias a 25 ± 2,0 ° C. As amostras de águas residuais diferiram na composição. A produtividade de biomassa foi 47% maior (P < 0,0001) nas águas residuais de produção de bovinos leiteiros do que de peixes, atingindo 67,61 g m-3 dia-1 (base de matéria seca, MS) quando comparada pelo teste t de Student (P < 0,05). O meio de cultivo também afetou a composição química da biomassa. C. vulgaris cultivado em águas residuais de gado leiteiro teve maiores teores de proteína bruta e cinzas (359,6 g kg-1 MS e 230,4 g kg-1 MS, respectivamente), enquanto microalgas cultivadas em águas residuais de criação de peixes apresentaram maior teor de extrativo não nitrogenado (347,8 g kg−1 DM). O teor de extrato etéreo não variou (média de 313,15 g kg-1 MS). O pH (8,0 a 8,7) e a concentração de amônia (0,07 a 0,40 mg L−1) as águas residuais dos peixes permaneceram estáveis ao longo do período experimental de 16 dias. Nas águas residuais de laticínios, o pH aumentou (6,3 para 8,9) até o quarto dia e permaneceu constante a partir de então, e a concentração de amônia aumentou até o oitavo dia (24.3 to 28.7 mg L−1) e então declinou (2.1 mg L−1). A C. vulgaris foi cultivada com sucesso em ambas as águas residuais, mas a produtividade foi maior nas águas residuais de gado leiteiro.(AU)

Assuntos

RESUMO

The objective of this study was to estimate the sulphur amino acid (methionine + cystine) requirements and nitrogen endogenous losses in kittens aged 150 to 240 d. Thirty-six cats were distributed in six treatments (six cats per treatment) consisting of different concentrations of methionine + cystine (M + C): T1, 6.5 g/kg; T2, 8.8 g/kg; T3, 11.3 g/kg; T4, 13.6 g/kg; T5, 16.0 g/kg; and control, 6.5 g/kg. Diets were formulated by serial dilution of T5 (a diet relatively deficient in M + C but containing high protein concentrations) with a minimal nitrogen diet (MND). Thus, crude protein and amino acid concentrations in diets T1-T5 decreased by the same factor. The control diet was the T1 diet supplemented with adequate concentrations of M + C (6.5 g/kg; 8.8 g/kg; 11.3 g/kg; 13.6 g/kg and 16.0 g/kg). All diets were based on ingredients commonly used in extruded cat diets. Digestibility assays were performed for the determination of nitrogen balance. Nitrogen intake (NI) and nitrogen excretion (NEX) results data were fitted with an exponential equation to estimate nitrogen maintenance requirement (NMR), theoretical maximum for daily nitrogen retention (NRmaxT), and protein quality (b). M + C requirements were calculated from the limiting amino acid intake (LAAI) equation assuming a nitrogen retention of 45 to 65% NRmaxT. The NMR of kittens aged 150, 195, and 240 d was estimated at 595, 559, and 455 mg/kg body weight (BW)0.67 per day, respectively, and M + C requirements were estimated at 517, 664, and 301 mg/kg BW0.67 per day, respectively.

Assuntos

RESUMO

The aim of this study was to (i) gain an overview of the protocols of food preference tests in cats through a systematic review, (ii) assess the effects of test duration, time of day, and sex, and (iii) propose a statistical approach based on power analysis to determine sample size and analyze the results. The manuscripts included in this review had marked variations in the number of days (2-56), sample size (9-60 cats), feeding times (2.5-1440 min), and number of meals per day (1-2) during the test. Additionally to the literature review, three palatability tests (lasting 10 days each) were conducted with 40 cats (22 males and 18 females, 1.8 ± 0.16 years, 3.73 ± 0.90 kg) to assess the effects of test duration, time of day, and gender on the results. From the second day of the test, the sensitivity of the results was higher, because on the first day the results in one of the tests differed from the others (p = .0058). There was no difference (p > .05) between times of day (morning vs afternoon) or gender (males vs females) on the results of the feed intake ratio. For a SD of 0.20, p < .05, and delta of 0.10, the minimum number of cats for two-bowl assays is 23 (test power higher than 0.75).The sample size and test duration are critical factors in the decision making by the investigators about the design of food preference tests in cats. The use of a power test is recommended upon planning a food preference test protocol in cats.

Assuntos

RESUMO

The heritability of canine hip dysplasia in German Shepherd dogs was estimated using Bayesian methods. Data on hip score and status of 1632 dogs born from 1990 to 2013 were provided by the Brazilian Society of German Shepherd Breeders. Heritability estimates (mean ± standard deviation) were 0.1979 ± 0.058 for hip scores and 0.187 ± 0.055 for hip status. We observed no phenotypic trends and a small rate of genetic trend (0.52%) according to the year of birth, probably because of ineffective phenotypic selection and absence of genetic selection. The heritability estimates in this study can be used to achieve effective selective breeding and genetic gains, which in turn can result in improvements in dog health and welfare.

Assuntos

RESUMO

The present study used meta-analysis to assess the effects of supplementation on beef cattle performance in pastures in Brazil, classifying data by forage type. There were reviewed articles published from 1999 to 2007, and was done comparisons between performance animals without supplement (control) and supplemented animals, to determine the real effect of supplementation on performance, and to find the corrected daily gain in each study. The regression equations were obtained through the covariance, and correlation and level of significance, between dependent and independent variables were obtained using the SAS statistical program PROC CORR. In tropical pastures, animals showed a corrected daily gain of 0.31 kg day-1, with TDN intake from supplement equal to 0.43% of LW day-1. Temperate pastures showed a corrected daily gain of 0.17 kg day-1 and TDN intake from supplement was 0.77% of LW day-1. Supplements used in tropical forages, showed an average of 29% CP, with animals having a corrected daily gain of 0.25 kg day-1 and in temperate forage, crude protein was 17.4%.

O presente estudo utilizou a meta-análise para avaliar os efeitos da suplementação sobre o desempenho de bovinos de corte em pastagens, no Brasil, classificando os dados pelo tipo de forragem. Foram revisados artigos publicados entre os anos de 1999 e 2007, e realizadas comparações entre o desempenho de animais não-suplementados (controle) e animais suplementados, para determinar o efeito da suplementação sobre o desempenho animal, utilizando o ganho corrigido. As equações de regressão foram obtidas pela covariância, e as correlações e nível de significância entre as variáveis dependentes e independentes foram obtidas com o PROC CORR do programa estatístico SAS. Em forragens tropicais, os animais tiveram ganho diário corrigido de 0,31 kg dia-1, com um consumo de NDT do suplemento de 0,43% do PV/dia e em forragens de clima temperado apresentaram ganho diário corrigido de 0,17 kg dia-1, com um consumo de NDT do suplemento de 0,77% do PV dia-1. Os suplementos utilizados em forrageiras tropicais apresentaram teor médio de proteína bruta de 29%, com os animais tendo ganho diário corrigido de 0,25 kg dia-1, e nas forragens de clima temperado o teor de proteína bruta foi de 17,4%.