Characterisation and sensory appraisal of fresh 'molido' cheese from cows fed different levels of sunflower silage inclusion in small-scale dairy systems.

Small-scale dairy systems require feeding strategies to improve their productivity and sustainability. These systems in central Mexico mostly sell their milk to local artisan cheese makers. Cow diets influence milk and dairy products composition; therefore, the objective was to evaluate the effect on physicochemical characteristics, sensory appraisal, and economic performance of cheese made with milk from cows fed different levels of sunflower silage (SFSL). Treatments were the inclusion of SFSL in the forage DM component of diets (T0 = 0% SFSL; T20 = 20%; T40 = 40%; and, T60 = 60%). Physicochemical composition was analysed by analysis of variance in a completely randomised design and the sensory assessment of the cheese was with a hedonistic five-point scale and the results were analysed by means of descriptive statistics and a radar graph. Partial budgets were used for economic analyses. There were significant differences (P < 0.05) for all physicochemical variables (moisture content, cheese yield, protein, fat content, and pH) of the cheese, with higher values for yield, protein, and fat content in the treatments that included SFSL. Sensory assessment values were in the average perception range of judges. Treatments that included SFSL had lower production costs, higher margins over costs, and higher returns/costs ratios. The inclusion of sunflower silage at 40 and 60% of the forage component of diets for dairy cows in small-scale dairy systems had positive effects. Yields of cheese as well as protein and fat content were higher. There were positive sensory attributes that meant acceptance by consumers, lower production costs, and higher incomes from cheese making.

Productive, economic, and environmental effects of sunflower (Helianthus annuus) silage for dairy cows in small-scale systems in central Mexico.

Small-scale dairy systems (SSDS) are important source of livelihood and socio-economic wellbeing for the rearers in general. The reduction of methane emissions with the inclusion of sunflower seed or seed-meal in rations for dairy cows has been reported in several studies. However, studies pertaining to the use of sunflower silage in dairy cattle feeding are lacking. The present study was conducted to assess the productive, economic, and environmental effects of the inclusion of graded levels of sunflower silage at 0%, 20%, 40%, and 60% (SFSL) along with maize silage (MZSL) on a dry matter basis. The silage was provided to eight Holstein cows in two 4×4 Latin-squares with 14-day periods. The study encompassed the productive performance of the cows, composition of feeds, besides the feeding costs, and enteric methane emissions estimated. The study indicated that inclusion of SFSL in the diet enhanced (P<0.001) the FCM by 3.5% and milk-fat content. SFSL increased feeding costs, but income/feeding costs ratios did not differ across the treatments. The higher inclusion of SFSL reduced methane emissions/kg of DM intake, / kg of milk, and in energy lost as methane. The inclusion of sunflower silage in feeding strategies for cows may be a viable alternative by increasing their milk yields and milk fat content and reducing methane emissions without affecting the income/feeding costs ratios.

The effect of feeding whole-crop barley or black oat silage in the fatty acid content of milk from cows in small-scale dairy systems in the highlands of Mexico.

Diets have an important effect on the fatty acid (FA) content in milk from dairy cows so that feeding strategies may modify the FA profile. There is little information on the fatty acid contents of whole-crop barley (BLY) and black oat (BKO) silages and on milk from cows fed these silages that are an alternative forage for small-scale dairy systems (SSDS). Given the growing interest in foods with favourable health attributes, the objective was to identify the FA content of milk from dairy cows fed whole-crop BLY and BKO silages in small-scale systems. Three inclusion levels of BLY and BKO silage were assessed in nine lactating cows at pasture for 8 h/day and supplemented with 4.6 kg/DM/cow/day commercial concentrate. Treatments were BLY: 10 kg DM/cow/day BLY silage; BKO: 10 kg DM/cow/d BKO silage; and BLY/BKO: 5 kg BLY and 5 kg DM/cow/d BKO silages (50:50). A 3 × 3 Latin square design repeated three times with nine cows and 14-day periods was utilised. Variables evaluated were the content of fatty acids present in feeds and milk. Contents of linoleic (C18:2n-6) and linolenic (C18:3n-3) acids, as precursors of polyunsaturated fatty acids, were 46 in BLY and 50 BKO g/100 g, lower than for multispecies pasture (61 g/100 g). There were statistical differences in the content of short-chain fatty acids in milk (P < 0.05), being lower for BLY (18.9 g/100 g) compared with BKO (20.4 g/100 g) and BLY/BKO (20.6 g/100 g), the saturated fatty acids and linoleic acid (C18:2n-6c) were higher in BLY/BKO in relation to BLY and BKO. Content of health-promoting polyunsaturated fatty acids in milk was higher in BLY/BKO (P < 0.05). There were no differences (P < 0.05) in the atherogenic index, with values within reports. Small-grain cereal forages may produce milk with a favourable fatty acid content for human health.

In vitro nutritional quality and antioxidant activity of three weed species as feed additives for sheep in the Central Highlands of Mexico.

Sheep production is traditional for rural communities in Mexico, based on natural grasslands and semi-stabled feeding. Quality forages are necessary to improve productivity in these systems. Weeds are an alternative to feed ruminants and to manage crops. Also, many plants have secondary metabolites beneficial for livestock. The objective was to assess the nutritive value in vitro and the antioxidant activity of three weeds (Tithonia tubiformis, Cosmos bipinnatus, and Tagetes lucida) and four treatments (T0 = control diet, T1 = diet + 5% T. tubiformis, T2 = diet + 5% C. bipinnatus, and T3 = diet + 5% T. lucida). Nutritive value was determined from chemical composition by standard methods and mineral contents by inductively coupled plasma analyses. Secondary compounds, total phenols (TP), total tannins (TT), condensed tannins (CT), and phenolic compounds, were determined by high-performance liquid chromatography, and total antioxidant activity was determined by measuring the oxygen radical absorbance capacity. Rumen fermentation kinetics and in vitro digestibility of dry matter (IVDMD), organic matter (IVOMD), and neutral detergent fibre (IVNDFD) were determined per species and treatment by in vitro gas production. T. tubiformis had the highest CP and TP contents (P < 0.05), and C. bipinnatus had the highest fibre and CT contents (P < 0.05). Inclusion of T. lucida in the diet resulted in an 18% increase in TP content and a 30% increase in antioxidant activity in comparison to the control diet. No significant differences (P > 0.05) were found in rumen kinetics parameters, IVDMD, IVOMD, IVNDFD, or metabolizable energy, indicating that the tested weeds can be used as additives to increase antioxidant activity in sheep diets without negative effects.

Milk production and estimated enteric methane emission from cows grazing ryegrass pastures in small-scale dairy systems in Mexico.

The work assessed the productive response and estimated enteric methane (CH4) emissions of dairy cows grazing in small-scale dairy systems. Treatments were grazing annual pasture (AP) mainly of annual ryegrass and perennial pasture (PP) mainly of perennial ryegrass, complemented daily with 3.72 kg DM/cow of commercial concentrate. Eight Holstein cows were used in a double cross-over design with three 14-day-each experimental periods for animal variables and CH4 emissions. Pasture variables were analysed with a split-plot design. AP showed higher sward height (P < 0.05) with no differences (P > 0.05) in net herbage accumulation or in herbage chemical composition. Cows on AP yielded 24.6% more milk (P < 0.001) than grazing PP, but there were no differences in milk fat and protein content. There were differences (P ≤ 0.05) among periods for milk yields, but no differences among periods for milk fat and protein. Milk urea nitrogen was significantly higher (P < 0.001) in PP than in AP with no differences among periods. There was higher (P < 0.001) DMI for AP than PP with a significant decline (P < 0.05) as periods progressed. There was a trend (P = 0.08) for higher daily CH4/cow in AP, but significantly lower emissions (7.2%) in AP/kg DMI, and 20.1% lower emission intensity of g CH4/kg milk. The proportion of gross energy lost as CH4 for AP was lower (P < 0.01). Higher milk yields in AP resulted in a 26% higher margin over feed costs than for PP. Results show that grazing annual pastures with moderate concentrate supplementation results in higher milk yields, higher incomes, and reduces the intensity of CH4 emissions.

Whole-crop triticale silage for dairy cows grazing perennial ryegrass (Lolium perenne) or tall fescue (Lolium arundinaceum) pastures in small-scale dairy systems during the dry season in the highlands of Mexico.

The dry season in central Mexico is a difficult time for small-scale dairy systems to meet feed requirements for their herds as pasture growth is limited. Conserved forage options are needed to complement pastures. The objective was to assess on-farm the production of dairy cows complemented with triticale silage (X. Triticosecale Witt. (TSL)) at two levels of inclusion (5.0 and 7.5 kg DM/d), grazing pastures of two grass species during the dry season: perennial ryegrass (PRG; Lolium perenne) or tall fescue (TFC; Lolium arundinaceum) (TFC) with white clover (Trifolium repens), and 4.65 kg DM/d concentrate. Experimental design was a 2 × 2 factorial in repeated 4 × 4 Latin squares. Chemical composition of TSL was 96 g CP/kg DM, 667 g NDF/kg DM, 713 g in vitro enzymatic digestibility of OM (IVEDOM)/kg DM, and pH of 4.6. There were differences (P < 0.05) in net herbage accumulation (NHA) and sward height between pastures, with higher NHA in TFC than that in PRG, although the chemical composition of PRG was higher (P < 0.05) in PC, IVEDOM, and estimated ME. There were no differences (P > 0.05) in milk yield (12.3 ± 2.63 kg/cow/day), milk compositions (33.1 ± 0.45 g milkfat/kg, 41 33.3 ± 0.21 g milk protein/kg, 47.9 ± 0.36 g lactose/kg, and 10.47 ± 2.25 mg MUN/dL), body condition score (2.4 ± 0.22), or live weight (490 ± 72.8 kg). At a higher inclusion of TSL, there was lower intake of pasture. Inclusion of 5.0 kg DM/cow/day of triticale silage better complements grazing and sustains moderate milk yields when pasture growth and intake are limited.

Chemical composition, in vitro gas production, methane production and fatty acid profile of canola silage (Brassica napus) with four levels of molasses.

The objective of this study was to investigate the effect of four levels of molasses on chemical composition, in vitro digestibility, methane production and fatty acid profile of canola silages. A canola (Brassica napus var. Monty) crop was established in a small-scale agricultural farm and harvested 148 days after sowing. Four levels of molasses were tested with respect to the fresh weight (1.5 kg); these were 1% (CS-1), 2% (CS-2), 3% (CS-3) and 4% (CS-4) molasses, and 0% molasses (CS-0) was included as a control. A total of 45 microsilages were prepared using PVC pipes (4 in. of diameter × 20 cm of length), and the forage was compressed using a manual press. The effects of control and treatments were tested using the general linear model Y = µ + Ti + Eij. The linolenic acid (C18:3n3), palmitic acid (C16:0) and linoleic acid methyl ester (C18:2n6c) accounted for 30%, 21% and 10.5% of total fatty acids, respectively; the fermentation parameters and in vitro methane production were not affected (P > 0.05) by treatments; in vitro digestibility decreased significantly (P < 0.05) as the level of molasses increased. It was concluded that CS-4 improved the DM content by 9% and showed high content of linolenic acid methyl ester. The gross energy of canola silages could favour the oleic acid methyl ester.

Effect of stocking rate and supplementation on performance of dairy cows grazing native grassland in small-scale systems in the highlands of central Mexico.

The use and management of native grassland for dairy production during the rainy season was studied on two small-scale dairy farms in the highlands of central Mexico. Two stocking rates (2 and 4 cows/ha) and two levels of supplementation with commercial concentrate (4 and 6 kg/cow/day) under grazing were given to 12 milking Holstein cows in a 4 × 4 Latin square design replicated three times in a factorial arrangement. Net herbage accumulation (NHA), sward height, chemical composition, and in vitro digestibility of organic matter were recorded for the grassland, as well as vegetation cover and herbage mass 12 weeks post experiment. Animal performance variables were milk yield and composition, live weight, and body condition score. A partial budget analysis of feeding costs, returns, and margins was calculated. There were no differences between periods for NHA and herbage height and between plots for chemical composition (P > 0.05). However, there were highly significant differences among periods (P < 0.01) for organic matter, neutral detergent fibre (NDF), acid detergent fibre, in vitro organic matter digestibility (IVOMD), and estimated metabolisable energy (eME), with highly significant plot × period interactions (P < 0.01) for NDF, IVOMD, and eME. There were no statistical differences (P > 0.05) between treatments for milk yield, chemical composition of milk, live weight, or body condition score. Post-experimental vegetation cover was 72 % for both stocking rates, indicating there was no degradation of the grassland. Lower feeding costs were for the low supplementation treatments. It is concluded that a high stocking rate in studied native grasslands of 4 cows/ha with moderate concentrate supplementation supports a mean milk yield of 11.9 kg/cow/day during the rainy season without deleterious effects on the grassland.

[Diagnostic of health quality in artisanal cheese dairies of Zacazonapan municipality, State of Mexico]. / Diagnóstico de la calidad sanitaria en las queserías artesanales del municipio de Zacazonapan, Estado de México.

OBJECTIVE: To determine the prevalence and the degree of contamination by molds and yeasts (M&Y), aerobic mesophilic bacteria (AMB), total coliforms (TC) and Salmonella spp. (S). These microorganisms were considered indicators of quality and hygiene in the manufacturing environment of Zacazonapan cheese. MATERIALS AND METHODS: Samples from five cheese dairies at Zacazonapan municipality were collected. The samples were collected directly from hands, water, milk, curd, cheese and surface of utensils for cheese making. RESULTS: All surfaces sampled were contaminated, there was an evident lack of hygiene in the cheese making process, the microorganisms count during cheese manufacturing were: for milk; 6.8, 6.7 and 4.5 log10 CFU/ml for M&Y, AMB and TC, respectively. For cheese, the presence of S was detected and presented the following counting: 9.16, 9.23 and 9.18 log10 CFU/g to M&Y, AMB and TC. CONCLUSIONS: The lack of hygiene in dairies and implements for cheese manufacturing represents a risk for human health.

Molasses supplementation for dual-purpose cows during the dry season in subtropical Mexico.

The effect of including 9 % of molasses in supplements offered to dual purpose cows, during dry season in subtropical Mexico was determined. Forage availability in pastures during the dry season is reduced and of low quality. Molasses is a readily available source of energy that may improve forage utilization and could have a positive effect on cow's milk production and calves daily weight gain (CDWG). Twelve multiparous Brown Swiss cows (409 ± 33 kg of body weight and 136 ± 73 days in milk), and their calves were randomly assigned to two supplements (six cows per treatment). Control supplement (COS) consisted of cracked maize ears (CME), soybean meal and urea (14 % CP), and experimental supplement in which 9 % of CME was replaced by molasses (MOS). Cows received 4.5 kg/cow/day dry matter (DM) of supplement. Experiment lasted 10 weeks divided in five experimental periods (EP). Animal responses (milk yield, milk composition, body weight, body condition score and CDWG) were recorded at the end of every EP. A linear mixed model was used to analyse the data as a complete random design. Net profits from milk and beef due to supplements were estimated using partial budget approach. Average milk yield was 7 (kg/cow/day) with 30.6, 30.4 and 42.5 (g/kg milk) of fat, protein and lactose, respectively. Average cow weight was 422 kg and CDWG was 0.8 kg/day. No significant responses on animal production variables were found when 9 % of MOS was included in the supplement; however, total net income increased on 4 %, due to higher CDWG.

Oat and ryegrass silage for small-scale dairy systems in the highlands of central Mexico.

This study investigated the effects of the inclusion of oat-ryegrass silage (ORGS) in combination with maize silage (MSLG) in four treatments: T1 = 100 % ORGS, T2 = 67 % ORGS/33 % MSLG, T3 = 67 % ORGS/33 % MSLG, and T4 = 100 % MSLG to milking cows on continuous grazing with 4.7 kg DM of commercial dairy concentrate 18 % CP. Daily milk yield and composition, live weight, body condition score, and chemical composition of feeds were recorded during the last 4 days of the experimental periods. Feeding costs were calculated by partial budgets. Eight Holstein lactating cows were used in a replicated 4 × 4 Latin square, with 14-day periods. There were no statistical differences (P > 0.05) for milk yield (mean 15.5 ± 5.0 kg/day/cow) or composition (mean milk fat 34.6 ± 4.4 g/kg, protein 32.4 ± 3.1 g/kg, lactose 46.9 ± 1.6 g/kg), milk urea nitrogen (11.3 ± 2.1 mg/dl), live weight (434 ± 38 kg), or body condition score (2.4 ± 0.15). The silage cost of ORGS was 2.5 times higher than MSLG, so the feeding cost in T1 was 26 % higher per kilogram of milk than for T4, with T2 and T3 as intermediates. ORGS can be a substitute to maize silage in the proportions studied, although feeding costs were higher.

Effect of different combinations of soybean-maize silage on its chemical composition, nutrient intake, degradability, and performance of Pelibuey lambs.

Sheep raising in the state of Guerrero, México, is a primary activity that is worth about US$3,251,931 annually. The objective of the present study was to evaluate the chemical composition, degradability, nutrient intake, and animal performance of Pelibuey lambs fed on different combinations of maize-soybean silages. Twenty-one combinations of maize silage (MS) and soybean silage (SS) were evaluated at day 45 post-ensiling; in each combination, MS was replaced by 5 % of SS. The 21 combinations were analysed for crude protein (CP) and chemical composition. In order to obtain a statistical criterion of potential treatments for the animal feeding test, a cluster analysis was performed based on the CP contents of all combinations at day 45 post-ensiling. From cluster analysis, four treatments were selected T1 = 100-0 % (MS/SS), T8 = 65-35 %, T12 = 45-55 %, and T16 = 25-75 %. Results indicated that cluster analysis was useful for identifying the potential treatments for animal feeding based on the crude protein content. The dry matter (DM), organic matter (OM), and acid detergent lignin (ADL) contents did not declined significantly (P > 0.05) during the fermentation of silages but CP content decreased from day 0 to 45 post-ensiling. The treatment with the highest estimated microbial crude protein synthesis was T8 and it showed the highest metabolizable energy intake, high feed efficiency with a forage-concentrate ratio of 84:16.

Synergistic Interaction Effect of Artemisia cina n-hexane Extract and Tagetes lucida Ethyl Acetate Extract on Haemonchus Contortus.

PURPOSE: We analysed the possible synergistic activity among active extracts from Artemisia cina and Tagetes lucida combinations on Haemonchus contortus, a nematode parasitising sheep. METHODS: The work was carried out in vitro on eggs and infective larvae (L3) of H. contortus. The results were analysed with SAS 9.1, applying the ANOVA and Tukey test, and the lethal concentration (LC) values LC50 and LC90 were determined with regression analysis, employing Proc Probit of SAS 9.1. Additionally, the lethal concentration (LC) was calculated with LC50 and LC90 to determine the synergistic effect. RESULTS: The results demonstrated a high efficacy of the two plants studied on both nematode eggs and L3 larvae as well as of their combinations. The highest egg hatching inhibition was obtained with a 50/50 combination, and the best larvae mortality was obtained with 25% A. cina and 75% T. lucida at 10 mg/mL. Additionally, this combination showed a synergistic effect. CONCLUSION: The two plant species studied here can be applied as natural anthelmintic alternatives due to their high bioactive effect and synergistic response.

Bioactive compounds from the parasitic plant Arceuthobium vaginatum inhibit Haemonchus contortus egg hatching.

The aim of this study was to assess the in vitro ovicidal activity of an ethyl acetate extract from Arceuthobium vaginatum (EtOAc-E) and their subfractions (AvR5-AvR14) against Haemonchus contortus using the egg hatching inhibition (EHI) test. The EtOAc-E and subfractions were tested at 0.12-2.00 and at 0.015-2.0 mg/mL, respectively. Distilled water and methanol (2%) were used as negative controls and Thiabendazole (0.10 mg/mL) as a positive control. Treatments with a dependent effect on concentration were subjected to regression analysis to determine the effective concentrations (EC50 and EC90). The major secondary compounds present in the extract and subfractions were identified by high performance liquid chromatography (HPLC). The EtOAc-E and AvR9 exhibited the best ovicidal effect recording 97.5 and 100% of EHI at 0.25 mg/mL, respectively. The EtOAc-E and AvR9 displayed an EC50= 0.12 and 0.08 mg/mL, respectively. The HPLC analysis in the EtOAc-E and bioactive fractions indicated the presence of a polyphenol, glycosylated flavanones, quercetin glucoside, cinnamates, coumarin, cinnamic acid derivative, ferulic acid, coumarate, naringenin, protocatechuic acid and naringin. Results demonstrated that A. vaginatum extract and fraction is able to inhibit the egg hatch process of H. contortus and could be a viable option for the control of small ruminant haemonchosis.

Dairy goats fed sunflower hay intercropped with chickpea in small-scale systems. Part I: Animal performance / Cabras lecheras alimentadas con heno de girasol intercalado con garbanzo en sistemas de pequeña escala. Parte I: Desempeño animal / Cabras leiteiras alimentadas com feno de girassol consorciado com grão de bico em sistemas de pequena escala. Parte I: Desempenho dos animais

Abstract Background: Small-scale livestock systems provide quality food for a growing demand of animal protein worldwide. Although these systems help to improve rural living standards and reduce the environmental footprint new feeding strategies should be tested to improve animal productivity. Sunflower -which is native to México- and chickpea -also common in the study area- may be used as feed alternatives for dairy goats. Objective: To evaluate the effect of substituting corn straw with sunflower-chickpea hay on yield and nutrient composition of goat milk. Methods: In this participatory study, a total of 28 multiparous Saanen dairy goats were randomly assigned to two treatments (14 goats each) during a 30-day experiment in a small farm. Two weeks prior to the experiment all goats received an adaptation diet. One treatment (MZST) received a conventional diet of lucerne hay (200 g/goat/day) and concentrate (400 g/goat/day), plus 600 g/goat/day (50% of the ration) of corn straw. The second treatment (SFCPT) contained the same lucerne and concentrate content with 600 g/goat/day of sunflower-chickpea hay. Milk yield and composition, and live weight and body condition of the goats were recorded for each treatment. Results: SFCPT significantly increased milk yield, protein, and solids content, but no difference was observed in milk fat. Conclusion: Dietary supplementation of goats with sunflower and chickpea hay increases milk production, protein, and total solids content compared with corn hay.

Resumen Antecedentes: Los sistemas de producción animal en pequeña escala proveen alimentos de calidad para una demanda mundial creciente de proteina animal. Aunque estos sistemas ayudan a mejorar la calidad de vida rural y reducen la huella ambiental, se deben buscar nuevas estrategias de alimentación para incrementar la productividad animal. El girasol -originario de México- y el garbanzo -común en la zona de estudio- pueden usarse como alternativa para la alimentación de cabras lecheras. Objetivo: Evaluar el efecto de sustituir el heno de maíz con heno de girasol y garbanzo sobre el rendimiento y composición nutricional de la leche de cabra. Métodos: En este estudio participtivo, un total de 28 cabras multíparas lecheras Saanen fueron asignadas aleatoriamente a dos tratamientos (14 cabras a cada uno) durante 30 días en una finca pequeña. Dos semanas antes del experimento todas las cabras recibieron una dieta de adaptación. Un tratamiento (MZST) recibió una dieta convencional de heno de alfalfa (200g/cabra/día) y concentrado (400 g/cabra/día), más 600 g/cabra/día (50% de la ración) de heno de maíz. El segundo tratamiento (SFCPT) tuvo el mismo contenido de alfalfa y concentrado, pero con 600 g/cabra/día de heno de girasol-garbanzo. Se registraron los rendimientos y composición de leche, peso vivo y condición corporal de las cabras para cada tratamiento. Resultados: SFCPT incrementó significativamente el rendimiento de leche, y contenido de proteína y sólidos, pero no hubo diferencias en contenido de grasa. Conclusión: La suplementacion dietaria de cabras con heno de girasol y garbanzo aumenta la producción de leche y su contenido de proteína y sólidos totales en comparacion con el heno de maiz.

Resumo Antecedentes: Os sistemas de produção animal em pequena escala têm um papel importante no fornecimento de alimentos de qualidade para atender uma demanda mundial crescente desses produtos, para melhorar a subsistência rural e para reduzir a pegada ambiental. Há uma necessidade, porem, de aumentar a produtividade através de estratégias de alimentação melhoradas. O girassol é nativo do México e o grão-de-bico é uma cultura comum na área de estudo que podem representar uma alternativa na alimentação de caprinos leiteiros. Objectivo: Avaliar através de investigação participativa na exploração o efeito da substituição da palha de milho tradicionalmente utilizada na alimentação de cabras leiteiras por uma forragem alternativa adaptada à região, mas não utilizada até o momento, em termos de rendimento, composição química de leite fresco de cabras. Métodos: Vinte e oito cabras leiteiras Saanen multipares foram designadas aleatoriamente a dois tratamentos (14 cabras/tratamento), em um experimento de 30 dias numa fazenda de pequena escala. Duas semanas antes do experimento, todos os caprinos receberam uma dieta de adaptação. Um tratamento (MZST) recebeu a dieta convencional de feno de alfalfa (200 g/caprino/dia) e concentrado (400 g/caprino/dia) mais 600 g/caprino/dia (50% da ração) de palha de milho. O segundo tratamento (SFCPT) tinha a mesma proporção de alfalfa e concentrado, mas com 600 g/caprino/dia de feno de girassol e grão-de-bico. O rendimento e composição do leite, o peso vivo e a condição corporal das cabras foram registrados de cada tratamento. Resultados: SFCPT aumentou significativamente o rendimento do leite e o conteúdo de proteínas e sólidos, mas não houve diferença no conteúdo de gordura láctea. Conclusão: O tratamento com girassol e feno de grão de bico aumentou a produção de leite, o teor de proteína e os sólidos totais.

Dairy goats fed sunflower hay intercropped with chickpea in small-scale systems. Part II: Cheese yield and composition, sensory analysis, and economic performance / Cabras lecheras alimentadas con heno de girasol intercalado con garbanzo en sistemas de pequeña escala. Parte II: Rendimiento y composición del queso, análisis sensorial y desempeño económico / Cabras leiteiras alimentadas com feno de girassol consorciado com grão de bico em sistemas de pequena escala. Parte II: Rendimento e composição do queijo, análise sensorial e desempenho econômico

Abstract Background: Goat production has grown worldwide as a way to improve the quality of rural life and reduce the environmental footprint; nevertheless, there is a need to increase productivity through improved feeding strategies. The market demands healthier products with organoleptic characteristics similar to the traditional ones; thus, it is necessary to evaluate the effect of new forages for goats and its acceptance by consumers. Chemical and organoleptic composition of goat milk vary according to the diet which, in turn, affects the characteristics of cheese. Cheese texture, taste and smell are the most important sensory attributes for consumers. Objective: To evaluate the effect of substituting corn straw with sunflower hay associated with chickpea for dairy goats on yield, chemical composition and sensory acceptability of cheese, as well profitability. Methods: Twenty-eight Saanen dairy goats were randomly assigned to two treatments in a 30-day experiment on a small farm. The daily ration per goat in the MZST treatment (control treatment) consisted of alfalfa hay (200 g/goat/day) and concentrate (400 g/goat/day) plus 600 g/goat/day (50% of the ration) of corn straw. The SFCP treatment substituted corn straw with sunflower-chickpea hay; it had the same alfalfa and concentrate content, but with no corn straw and was added with 600 g/goat/day of sunflower-chickpea hay. The yield, composition and sensory evaluation of fresh cheese made with milk from each treatment were recorded, and the feeding costs and returns evaluated. Variables for the chemical composition of cheese were analyzed following a completely randomized design. Results: Significant differences were observed in cheese yield and all chemical composition variables. According to sensory evaluation, SFCP cheese had significantly higher scores for texture and odor but lower for taste and overall acceptability compared to MZST. In terms of profitability, SFCP increased feed costs by 5% but resulted in higher margins over feed costs of 12 and 24% for milk and cheese, respectively, compared to MZST. Conclusion: In spite of favorable performance and economic returns of MZST treatment (control treatment), the organoleptic characteristics of the cheese reduced its general acceptance.

resumen está disponible en el texto completo

Resumo Antecedentes: A produção de caprinos em todo o mundo tem crescido como forma de melhorar a qualidade de vida rural e reduzir a pegada ambiental; pero há uma necessidade de aumentar a produtividade através de estratégias de alimentação melhoradas. A crescente procura dos consumidores por produtos mais saudáveis mas com características organolépticas semelhantes aos tradicionais, tornou necessário desenvolver estratégias para satisfazer esta necessidade, pelo que é necessário avaliar o efeito de novas forrageiras nas dietas na sua aceitação pelos consumidores. A composição química e organoléptica do leite de cabra varia de acordo com a dieta, o que por sua vez afeta as características do queijo de leite de cabra. Entre os atributos sensoriais mais importantes para os consumidores estão textura, sabor e cheiro. Objetivo: Avaliar o efeito da substituição da palha de milho por feno de girassol associada ao grão-de-bico na alimentação de cabras leiteiras, em termos de rendimento, composição química e aceitabilidade sensorial do queijo, bem como desempenho econômico. Métodos: Vinte e oito cabras leiteiras Saanen foram distribuídas aleatoriamente em dois tratamentos em um experimento de 30 dias em uma fazenda de pequena escala. A ração diária por cabra no tratamento MZST (tratamento controle) consistia em feno de alfafa (200 g/cabra/dia) e concentrado (400 g/cabra/dia) mais 600 g/cabra/dia (50% da ração) de a palha de milho e o tratamento SFCP (tratamento substituiu o feno de girassol-grão moído) continham os mesmos teores de alfafa e concentrado, mas com 600 g/cabra/dia de feno de girassol-grão. O rendimento, a composição e a avaliação sensorial dos queijos in natura feitos com leite de cada tratamento foram registrados e os custos de alimentação e retornos avaliados. As variáveis de composição química dos queijos foram analisadas seguindo um delineamento inteiramente casualizado. Resultados: Houve diferenças significativas no rendimento do queijo e para todas as variáveis de composição química. A avaliação sensorial mostrou que o queijo SFCP teve pontuações significativamente mais altas para textura e odor, mas significativamente mais baixas para sabor e aceitabilidade geral em comparação com o MZST. Em termos econômicos, o SFCP aumentou os custos com alimentação em 5%, mas resultou em margens mais altas sobre os custos com alimentação de 12 e 24% para leite e queijo, respectivamente, em comparação com o MZST. Conclusão: Apesar do desempenho favorável e do retorno econômico com o tratamento MZST (tratamento controle), mudanças nas características organolépticas do queijo reduziram sua aceitação geral.

Diagnóstico de la calidad sanitaria en las queserías artesanales del municipio de Zacazonapan, Estado de México / Diagnostic of health quality in artisanal cheese dairies of Zacazonapan municipality, State of Mexico

Resumen: Objetivo: Determinar la prevalencia y el grado de contaminación por mohos y levaduras (M&L), bacterias mesófilas aerobias (BMA), coliformes totales (CT) y Salmonella spp. (S) como indicadores de calidad e higiene en el entorno de fabricación del queso de Zacazonapan. Material y métodos: En cinco queserías se obtuvieron muestras de agua, leche, cuajo y queso, y de superficie de las manos y de los utensilios que están en contacto con el queso. Resultados: Todas las superficies presentaron contaminación; por lo tanto, se observa falta de higiene al elaborar el queso. Los conteos durante la elaboración de queso fueron, para leche, de 6.8, 6.7 y 4.5 log10 UFC/ml para M&L, BMA y CT, respectivamente. En queso, se detectó la presencia de S y cuentas de 9.16, 9.23 y 9.18 log10 UFC/g para M&L, BMA y CT. Conclusiones: La poca higiene en queserías y utensilios al elaborar el queso representa un riesgo para la salud humana.

Abstract: Objective: To determine the prevalence and the degree of contamination by molds and yeasts (M&Y), aerobic mesophilic bacteria (AMB), total coliforms (TC) and Salmonella spp. (S). These microorganisms were considered indicators of quality and hygiene in the manufacturing environment of Zacazonapan cheese. Materials and methods: Samples from five cheese dairies at Zacazonapan municipality were collected. The samples were collected directly from hands, water, milk, curd, cheese and surface of utensils for cheese making. Results: All surfaces sampled were contaminated, there was an evident lack of hygiene in the cheese making process, the microorganisms count during cheese manufacturing were: for milk; 6.8, 6.7 and 4.5 log10 CFU/ml for M&Y, AMB and TC, respectively. For cheese, the presence of S was detected and presented the following counting: 9.16, 9.23 and 9.18 log10 CFU/g to M&Y, AMB and TC. Conclusions: The lack of hygiene in dairies and implements for cheese manufacturing represents a risk for human health.

Nutritional value of forage species from the Central Highlands Region of Mexico at different stages of maturity / Valor nutricional de espécies forrageiras nativas da Região Central Montanhosa do México em diferentes estádios de maturidade

This paper has two objectives, the first is to determine the chemical composition, gas production parameters and the gas release kinetics, at different stages of maturity, of three grasses and a legume commonly found in long established pastures in Mexico central highland plateau. The second is to combine the gas release kinetics analysis and the GP fitted to a mathematical model in order to improve the biological understanding of the fermentation kinetics obtained from the GP technique. Representative samples of Pennisetum clandestinum (kikuyu grass), Sporobolus indicus (mouse tail), Eleocharis dombeyana (reed), Trifolium amabile (Aztec clover) plus a composite sample were collected in the growing season (July, September and November 2003) and analysed using an in vitro gas production (GP) technique. The accumulated GP was fitted to the model described in PALMER et al. (2005). Significant differences (P<0.001) were observed among species and periods for chemical composition, organic matter and neutral detergent fibre digestibility. Significant differences (P<0.05) were observed regarding fermentation parameters and gas release kinetic, with T. amabile and P. clandestinum being the species with the highest fermentability, whereas S. indicus and E. dombeyana were poorly fermented. P. clandestinum and T. amabile showed higher nutritive value than S. indicus and E. dombeyana. Composite samples were influenced by the chemical and fermentation characteristics of all species. It was concluded that the use of gas release kinetics analysis was useful for differentiating the fermentation kinetic of the soluble and insoluble fraction in the grasses and legume. Therefore by performing both approaches, the gas release kinetics analysis and the GP fitted to a mathematical model, gave a better description of the fermentation kinetic of grasses and the legume was achieved when only one approach had been used.

O uso da análise de cinética de produção de gases, em conjunto com a análise de prova de curva e as propriedades químicas da forragem permitem uma melhor descrição das características nutritivas das forragens. Objetivou-se estudar a composição nutritiva e características de fermentação de ruminal de três gramíneas, uma leguminosa e uma mistura composta de pastagens do Planalto Montanhoso Central do México. As amostras representativas de Pennisetum clandestinum (kikuyu grama), Sporobolus indicus (rabo de rato), Eleocharis dombeyana (cana), Trifolium amabile (trevo asteca) mais uma amostra composta foram coletadas durante os meses de Julho, Setembro e Novembro de 2003. Foi utilizada a técnica de produção de gás in vitro (GP). Os perfis de GP foram ajustados ao modelo descrito por PALMER et al. (2005). As diferenças (P<0.001) foram observadas entre espécies e períodos quanto à composição química, matéria orgânica e digestibilidade da fibra em detergente neutro. As diferenças (P<0.05) dos parâmetros de fermentação e cinética de produção de gases mostraram T. amabile e P. clandestinum com fermentação mais intensa, ao passo que S. indicus e E. dombeyana tiveram fermentação limitada. Concluiu-se que a combinação da análise de cinética de produção de gases e o perfil de GP ajustado ao modelo matemático ajudou a descrever as características nutritivas das gramíneas, da leguminosa e da amostra composta de forma mais acurada do que quando um dos métodos foi utilizado de forma isolada.