Luis Sarmiento-Franco

Productive performance of Creole chickens and their crosses raised under semi-intensive management conditions in Yucatan, Mexico.

1. The productive performance of 4 chicken breed groups managed under semi-intensive conditions in Yucatan, Mexico was evaluated. Thirty-six mixed chickens, one week of age of each of the 4 breed groups (Creole, F1 Hubbard × Creole, 7/8 Hubbard × 1/8 Creole and Hubbard) were used. 2. During 1 to 3 weeks of age all birds were fed on a diet containing 210 g/kg crude protein (CP) and 12·95 MJ/kg metabolisable energy (ME). From weeks 4 to 7, they were given a diet with 190 g/kg CP and 12·55 MJ/kg ME. Food consumption and live body weight were recorded weekly. Statistical analysis of the data was performed according to complete randomised design and means comparison using Tukey test was carried out when necessary. 3. Creole chicks had the lightest weights at all ages as compared to their crosses and the Hubbard birds. At 7 weeks of age, Creole chicks were 2·11, 2·44 and 2·90 times lighter than their contemporary F1, 7/8 Hubbard × 1/8 Creole and Hubbard birds, respectively. Hubbard birds were heavier than F1 and 7/8 commercial × 1/8 Creole birds, and the latter group heavier than the F1 birds. Similarly, Creole chicks had the lowest growth rate compared to the other genetic groups. Heterosis for body weight up to 7 weeks of age was 8·2%. 4. Feed consumption was also lower for the Creole chicks at all ages. Food:gain ratio, however, was higher for the Creole chicks at all ages. Food:gain ratios from weeks 2 to 7 were 2·18, 2·65, 3·04 and 4·36 for the Hubbard, 7/8 Hubbard × 1/8 Creole, F1 and Creole birds, respectively. Heterosis for food:gain ratio from 2 to 7 weeks of age was −7·0%. 5. Crossbreeding of Mexican Creole birds with commercial type broilers might improve productive performance.

Performance of Broilers Fed on Diets Containing Different Amounts of Chaya (Cnidoscolus aconitifolius) Leaf Meal

The performance and gut measurements of broilers fed on diets containing different amounts of chaya (Cnidoscolus aconitifolius) leaf meal (CLM) were examined in two experiments. In the first experiment, 60 Hubbard chickens (30 males and 30 females; 2 weeks old) were fed on five maize diets; these were formulated using 0, 150 (CLM150), 250 (CLM250) or 350 (CLM350) g CLM/kg, and the fifth diet contained soyabean. In the second experiment, 148 Ross male chicks, 1 day old, were fed on three isonitrogenous and isoenergetic maize–soyabean-based diets, which included 0 (control), 150 (C150) or 250 (C250) g CLM/kg. The diets were offered ad libitum for 2 or 3 weeks in the first and second experiments, respectively. Food intake, weight gain and the food:weight gain ratio were recorded. The weight of the gizzard and intestine and the weight and length of the caeca were also determined in the second experiment. In experiment 1, the birds fed on the maize–soyabean diet had a higher (p<0.05) weight gain and final weight than birds fed on maize only or on the CLM150 diets. There were no differences for any of the variables studied between the birds fed on the maize–soyabean diet and those fed on the CLM250, nor between males and females. In the second experiment, weight gain, food intake and the food:weight gain ratio for birds fed on C250 were lower (p<0.05) than those in birds fed on either the control or C150 diets. The weights of the gizzard and intestine were the lowest and the highest, respectively, in birds fed on C250 (p<0.05). The length and weight of the caecum from birds fed on the control diet were lower (p<0.05) than those of birds fed on either the C150 or C250 diets. The results from this study suggest that CLM may be included up to 150 g/kg in commercial diets without having an adverse effect on poultry performance, and may also be mixed with maize up to 250 g/kg to improve the performance of chickens fed on low-protein diets.

Determination of Tropical Forage Preferences Using Two Offering Methods in Rabbits

Two methods of feed preference trials were compared to evaluate the acceptability of 5 fresh foliages: Leucaena leucocephala, Moringa oleifera, Portulaca oleracea, Guazuma ulmifolia, and Brosimum alicastrum that was included as control. The evaluation included chemical analyses and forage intake by rabbits. The first method was a cafeteria trial; 12 California growing rabbits aged 8 wk, allocated in individual cages, were offered the five forage plants at the same time inside the cage, while in the second trial 60 California growing rabbits aged 8 wk, allocated individually, were randomly distributed into 5 experimental groups (n = 12/group); for each group just one forage species was offered at a time. The testing period for each method lasted for 7 d, preceded by one week of adaptation. The results showed that B. alicastrum and L. lecocephala were the most preferred forages while on the contrary G. ulmifolia was the least preferred one by rabbits. The results also revealed that the CV% value for the 2nd method (16.32%), which the tested forages were presented separately to rabbits, was lower and methodologically more acceptable than such value for the 1st method (34.28%), which all forages were presented together at the same time. It can be concluded that a range of tropical forages were consumed in acceptable quantities by rabbits, suggesting that diets based on such forages with a concentrate supplement could be used successfully for rabbit production. However, growth performance studies are still needed before recommendations could be made on appropriate ration formulations for commercial use.

Estimating Apparent Nutrient Digestibility of Diets Containing Leucaena leucocephala or Moringa oleifera Leaf Meals for Growing Rabbits by Two Methods

This study aimed to evaluate the nutrient digestibility of growing rabbits fed diets with different levels of either Leucaena leucocephala (LLM) or Moringa oleifera (MOLM) leaf meals and also to compare total collection and TiO2 marker methods for estimating digestibility. A total of 30 California growing rabbits (1.81±0.19 kg live weight on average) were randomly distributed into five experimental groups of six rabbits each and were housed in individual cages. The groups were control, 30% LLM, 40% LLM, 30% MOLM, and 40% MOLM. All groups received pelleted diets for two weeks; diets also contained 4 g/kg titanium dioxide as dietary marker. Daily feed intake was recorded during the whole experimental period and total feces were collected daily and weighed individually during four days. The results showed that there were no difference (p>0.05) in feed, dry matter (DM), organic matter (OM), crude protein (CP), digestible energy, and crude fiber (CF) intake between the control group and the other experimental groups. The apparent digestibility values of DM, OM, CP, CF, acid detergent fiber, and gross energy were the highest for control group (p = 0.001), meanwhile MOLM diets had generally higher nutrient digestibility coefficients than LLM diets. Increasing the inclusion level of leaf meal in the diet from 30% to 40% improved the digestibility of CF from 45.02% to 51.69% for LLM and from 48.11% to 55.89% for MOLM. Similar results for apparent nutrient digestibility coefficients were obtained when either total collection or indigestible marker method was used. In conclusion, the digestibility of MOLM containing diets were better than LLM diets, furthermore TiO2 as an external marker could be used as a simple, practical and reliable method to estimate nutrients digestibility in rabbit diets.

Poultry meat production in free-range systems: perspectives for tropical areas

The objective of the current paper is to review research findings in organic poultry or free-range systems and its perspectives for the tropical Latin America region, including genotypes adapted to production systems in semi-captivity, according to the specific characteristics of each country. Different feeding systems schemes are analysed as well as low cost feed resources that could be used. Most of the studies reviewed for free-range systems propose feeding schemes based on two stages, which are starter (1-5 weeks old) and finisher (5-15 weeks old) diets. Carcass yield and quality are covered; however there is still debate due to the great variety of results observed, depending on age, genotype, feed ingredients and characteristics of the system used. It has been suggested that carcass characteristics improved due to increased activity, which enhances bird comfort and welfare. The findings of this review indicated that producing meat in these systems is feasible in tropical countries. However, it is necessary to establish adequate conditions for every country to ensure viability, on the basis of meat quality and economic variables.

The effect of two housing systems on productive performance of hair-type crossbreed lambs in sub-humid tropics of Mexico

ABSTRACT The effect of two housing systems during the fattening period on productive performance of lambs from different hair-type sheep breeds in southeastern Mexico was evaluated. Effects of housing system (raised-slatted floor cages (RFC) vs. floor pens (FP)), year (2009, 2012 and 2013) and season of the year (rainy vs. dry) on average daily gain (ADG), weights adjusted to 60 (P60) and 90 (P90) days post-weaning were evaluated. Data from 1213 lambs collected on the farm over a period of three years were analysed. The ADG, P60 and P90 were affected (P < .01) by the housing system, year and the housing system × year interaction. The season was not a significant source of variation. Lambs housed in RFC were heavier (ADG 306.5 ± 2.69 g, P60 33.2 ± 0.16 kg, P90 42.4 ± 0.24 kg) than those in FP (ADG 269.4 ± 4.24 g, P60 30.9 ± 0.25 kg, P90 39.0 ± 0.38 kg) (P < .01); however, the significant interaction housing system × year suggests that productive performance of lambs may vary between years, despite the housing system. It was concluded that productive performance of hair lamb was affected by housing systems, year and their interaction.

Outdoor egg production using local forages in the tropics

The following review discusses the findings of existing research surrounding the nutritional impact of leaf meals as incorporated in chicken diets, the importance of forages in sustainable poultry production and the capacity of hens to digest high fibre diets. The potential of conventional and/ or outdoor based systems for developing countries, the effects of outdoor production systems on the welfare of laying hens, and methods used in measuring forage intake and the feed items obtained by hens from the outdoor area are also discussed. This review highlights those factors affecting range utilisation, behaviours of free range hens and the recommendations for better range utilisation by laying hens, particularly in the tropics.

The effect of chaya (Cnidoscolus aconitifolius) leaf meal and of exogenous enzymes on amino acid digestibility in broilers.

1. The apparent ileal nitrogen (N) and amino acid digestibilities in chaya leaf meal (CLM) (Cnidoscolus aconitifolius) with added enzymes, and the same variables in diets containing different amounts of CLM were studied in chickens. 2. In the first experiment pectinase, β-glucanase, and pectinase + β-glucanase were added to CLM. In the second experiment, there were three diets based on maize and soybean: 0, 150 and 250 g/kg CLM. 3. Pectinase significantly increased both lysine and overall amino acid digestibilities in CLM. 4. In experiment 2, the amino acid digestibility in birds fed on CLM250 was lower than that from birds fed on either control or CLM150. Only the digestibilities of alanine, arginine and proline were lower in birds fed on CLM150 than in those fed on the control diet. Nitrogen digestibility was lower in birds fed on the CLM250 diet than on either control or CLM150 diets. These findings were attributed to the increasing concentration of fibre with increasing dietary CLM.

Nutrient Digestibility and Metabolizable Energy Content of Mucuna pruriens Whole Pods Fed to Growing Pelibuey Lambs

The nutrient digestibility, nitrogen balance and in vivo metabolizable energy supply of Mucuna pruriens whole pods fed to growing Pelibuey lambs was investigated. Eight Pelibuey sheep housed in metabolic crates were fed increasing levels of Mucuna pruriens pods: 0 (control), 100 (Mucuna100), 200 (Mucuna200) and 300 (Mucuna300) g/kg dry matter. A quadratic (p<0.002) effect was observed for dry matter (DM), neutral detergent fibre (aNDF), nitrogen (N) and gross energy (GE) intakes with higher intakes in the Mucuna100 and Mucuna200 treatments. Increasing M. pruriens in the diets had no effect (p>0.05) on DM and GE apparent digestibility (p<0.05). A linear reduction in N digestibility and N retention was observed with increasing mucuna pod level. This effect was accompanied by a quadratic effect (p<0.05) on fecal-N and N-balance which were higher in the Mucuna100 and Mucuna200 treatments. Urine-N excretion, GE retention and dietary estimated nutrient supply (metabolizable protein and metabolizable energy) were not affected (p>0.05). DM, N and GE apparent digestibility coefficient of M. pruriens whole pods obtained through multiple regression equations were 0.692, 0.457, 0.654 respectively. In vivo DE and ME content of mucuna whole pod were estimated in 11.0 and 9.7 MJ/kg DM. It was concluded that whole pods from M. pruriens did not affect nutrient utilization when included in an mixed diet up to 200 g/kg DM. This is the first in vivo estimation of mucuna whole pod ME value for ruminants.

Egg Production and Quality in Laying Hens Fed on Different Digestible Amino Acid Regimes and Housed at Three Stocking Densities

Abstract Vázquez-González, L., Sarmiento-Franco, L., Santos-Ricalde, R., Carvajal-Hernández, M., Segura-Correa, J. and Gutiérrez-Triay, M. 2008. Egg production and quality in laying hens fed on different digestible ammo acid regimes and housed at three stocking densities. J. Appl. Anim. Res., 33: 175–180. The objective of the present study was to compare the production performance and egg quality in hens fed on 3 different digestible amino acid regimes and housed at three stocking densities. One hundred and sixty two light Isa-Babcock B300 laying hens were allocated randomly according to 2, 3 or 4 birds per cage. The birds were fed on different diets: 70 (CP: 14.4%), 90 (CP: 17.37%) and 110% (CP: 21.58%) of essential digestible amino acids requirements. The effect of digestible amino acids concentration was significant (P>0.05) for egg weight, albumin weight and albumin width as well as N dropped and crude protein content of excreta. Hen stocking density affected (P>0.05) only feed intake. It is concluded that 90% of essential digestible amino acids requirements and 4 hens per cage density (40x40 cm) could contribute to reduce N pollution without adversely affecting egg production.