Performance and carcass characteristics of Santa Inês lambs fed different protein sources

The objective of this study was to evaluate the productive performance and carcass characteristics of confined Santa Inêssheep, fed different diets, in a Semiarid environment. Twenty whole sheep with 5 ± 0.5 months of age and 27 ± 2.0 kg were used, receiving two different diets for 72 experimental days, one composed of defatted soybean meal and the other of protein-enrichedcactus meal. They were evaluated for different diets, consumption, production, carcass characteristics, morphometric measures and edible components. The experimental design was in randomized blocks with two treatments and 10 replications. Performance dataand carcass characteristics were evaluated by analysis of variance and means compared by t test at 5% probability level using Statistical Analysis System [SAS]®(1999). Thus, the use of emulsified palm forage protein in the feeding of Santa Inês male lambs proved to be an excellent protein source when compared to the use of defatted soybean meal, since the results of performance and carcass characteristics were similar, being the use of this alternative source advised as it presents the best benefit-cost ratio.(AU)

Effect of the performance, calving date and lactation period on the probability of pregnancy in beef cows

Determining what and how much each environmental factor affects pregnancy is crucial to the sustainability and management of beef cow herds. The study evaluated through logistic regression the effect of environmental variables on the increase or reduction in the pregnancy rate of beef cows. The average pregnancy rate in the cows was 73 %, with an average age for the herd of 3.7 years. An increase in age of one year represented a 30 % increase in pregnancy, while a reduction of one year reduced the odds of pregnancy in the cows by 23 %. During the lactation period, an extra seven days' lactation reduced the odds of pregnancy by 12 %. For every seven days that weaning was brought forward, the cows' pregnancy odds increased by 14 %. An increase of 0.1 kg in average daily gain represented an increase of 17 % and 15 % in the odds of pregnancy during the first 60 days post-partum and 60 days to the end of the reproductive period. On the other hand, the loss of 0.1 kg in average daily gain resulted in a 14 % and 13 % reduction in the cows' pregnancy odds, respectively. Factors such as age, the precocity of calving in the calving season, the time the calf remains with the cow and better performance in cows between calving and the end of the mating are strategies that increase the chances of pregnancy in beef cows.(AU)

The correlation between body weight, body weight gain and blood parameters in pigs at birth and weaning / A correlação entre peso corporal, ganho de peso corporal e parâmetros sanguíneos em suínos ao nascimento e desmame

The aim of study was to determine the relationship between metabolic parameters, body weight and body growth of piglets at birth and weaning. The experiment included 80 piglets obtained from F1 generation sows. Body weight was measured at birth (BW0), 24h (BW1) after birth and on day 25 (at weaning, BW2). Blood sampling was performed at the beginning of life (3rd day after birth) and at weaning (21st day after birth). BW0 and BW1 positively correlated with cholesterol and negatively with urea values at the beginning of life and RBC values at weaning. BW2 positively correlates with albumin and cortisol values at the beginning of life, total proteins, and globulins at weaning, and negatively correlates with erythrocyte values at weaning. Piglet growth from birth to weaning (BWG2-0) correlates positively with total proteins, albumin, and cortisol at the beginning of life and total proteins at weaning. ROC analysis shows that MCHC, TPROT, GLOB, CHOL and AST at the beginning of life can distinguish fast-growing from slow-growing piglets from birth to weaning period. The use of blood parameters enables early recognition of growth rate in piglets, which can help to optimize all further steps to achieve the best possible growth.

O objetivo do estudo foi determinar a relação entre parâmetros metabólicos, peso corporal e crescimento corporal de leitões ao nascimento e desmame. A experiência incluiu 80 leitões obtidos de porcas da geração F1. O peso corporal foi medido ao nascimento (BW0), 24h (BW1) após o nascimento e no dia 25 (no desmame, BW2). A amostragem de sangue foi realizada no início da vida (3º dia após o nascimento) e no desmame (21º dia após o nascimento). BW0 e BW1 correlacionaram-se positivamente com o colesterol e negativamente com os valores de uréia no início da vida e com os valores de hemácias no desmame. BW2 correlaciona-se positivamente com os valores de albumina e cortisol no início da vida, proteínas totais e globulinas no desmame, e negativamente com os valores de eritrócitos no desmame. O crescimento do leitão desde o nascimento até o desmame (BWG2-0) se correlaciona positivamente com as proteínas totais, albumina e cortisol no início da vida e com as proteínas totais no desmame. A análise ROC mostra que MCHC, TPROT, GLOB, CHOL e AST no início da vida pode distinguir leitões de crescimento rápido de leitões de crescimento lento desde o nascimento até o desmame. O uso de parâmetros sanguíneos permite o reconhecimento precoce da taxa de crescimento em leitões, o que pode ajudar a otimizar todas as etapas posteriores para alcançar o melhor crescimento possível.

Investigation of Egg Weight, Ovarian Follicles Morphology and Growth Differentiation Factor 9 mRNA Expression in Potchefstroom Koekoek Chicken Breed

The growth differentiation factor 9 (GDF9) gene plays a vital role in the growth and maturation of ovarian follicles in laying hens. However, its messenger ribonucleic acid (mRNA) expression levels in preovulatory ovarian follicles of indigenous chickens remain poorly understood. The study aimed to identify the association between egg weight and egg quality traits, ovarian follicles morphology, and mRNA expression levels of the GDF9 gene in pre-ovulatory ovarian follicles of the South African Potchefstroom Koekoek chicken breed. The correlation results showed that egg weight (EW) had a positively high significant correlation (p<0.01) with egg width (EWD), yolk weight (YW), shell surface area (SSA), albumen weight (AW), albumen ratio (AR) and egg volume (EV), and a positive significant correlation (p<0.05) with egg length (EL). The Student's T-test results revealed that the numbers of large yellow follicles were significantly lower (p<0.05) than those of small yellow follicles. ANOVA findings showed that there was a significant difference (p<0.05) in the average weight of the large yellow follicles. The quantitative Reverse Transcription Polymerase Chain Reaction (RT-qPCR) findings indicated that there were significant differences (p<0.05) in the mRNA expression levels of the GDF9 gene in preovulatory ovarian follicles of the Potchefstroom Koekoek chicken breed. The mRNA expression was more abundant in F1 and F4 than in other ovarian follicles.(AU)

Replacement of Conventional Vegetable Oil with Granulated Fats of Palm Oil (Prilled Fats and Calcium Soaps) in Broiler Chicken Diet: Performance and Carcass Traits

This study evaluated the productive performance and carcass characteristics of broiler chickens fed diets containing prilled fats of palm oil (PFPO) or calcium soaps of palm oil (CaSPO) replacing vegetable oils (VO). A total of two hundred 1-day-old male Ross 308 chickens were allocated in a 2 × 2 randomized factorial design. Diets included 2 PFPO levels (0 and 50%) and 2 CaSPO levels (0 and 50%). The level was the percentage of substitution of VO by granulated fats. The study had two phases (starter and finisher), each lasting 21 days. In the starter phase, PFPO did not influence (main effects; p>0.05) feed intake and body weight gain, but improved (main effect; p=0.03) feed conversion. In the finisher phase and the total study, PFPO had no effect (p>0.05) on these productive variables. Throughout the study, CaSPO did not influence feed intake (main effect; p>0.50), but decreased weight gain and had a negative effect on feed conversion (main effects; p<0.05). There was no influence of fats (PFPO or CaSPO) on carcass yield, breast, drumsticks plus thighs, and wings (main effects; p>0.05). Chickens fed CaSPO had lower (main effect; p=0.02) carcass weight. The only PFPO × CaSPO interaction (p=0.04) was for back yield. Results showed that PFPO or CaSPO could be employed in formulating broiler chicken diets, as they are less expensive than conventional VO. Partial substitution of VO for PFPO had minimal effect on productive variables, although partial dietary inclusion of CaSPO might slightly reduce the production of broiler chickens.(AU)

Effects of dietary fiber on performance and egg quality of laying hens at pre-laying and laying peak

This study aimed to evaluate the effects of different levels of dietary fiber on the performance and egg quality of laying hens at pre-laying and laying peak periods. The experimental period was divided into three periods: pre-laying (16 to 19 weeks of age), the start of laying (20 to 22 weeks of age) and laying peak (23 to 28 weeks of age). The experimental design was completely randomized with treatments constituted by five levels of fiber (2.00, 2.50, 3.00, 3.50, and 4.00%) in the diets, with five replicates (pens) of six birds each, totalling 180 hens. Performance and egg quality results were evaluated by polynomial regression at 5%. Fiber levels were not influenced (p >0.05) the first laying of the hens. However, levels above 2.50% of fiber provided worst (p <0.05) performance results, regardless of the period evaluated. Shortly after the start of laying, higher levels of fiber also caused a linear reduction (p <0.05) on egg weight and percentages of yolk and albumen, and an increase (p <0.05) on eggshells. Higher fiber levels caused a linear reduction (p <0.05) in the quality of the eggs, regardless of the period evaluated. It was concluded that the fiber levels did not influence the start period of the laying. Both pre-laying and start of the laying, levels above 2.5% of fiber caused a gradual worsening in performance. From the start of laying up to laying peak, levels above 2.5% of fiber also caused a gradual worsening in egg quality.(AU)

Effects of Bee Pollen Inclusion on the Performance and Gut Morphology of Ross 308 Broiler Chickens

This study was conducted to determine the effect of bee pollen inclusion on the performance and gut morphology of Ross 308 broiler chickens. A total of 240-day-old chicks (120 males and 120 females) were allocated to 4 treatments in a randomized complete block design (RCBD) with sex as a block. Each experimental group was replicated 3 times with 10 chicks per replicate, with an average weight of 40 ± 5g per bird. Body weight and feed intake were measured on a weekly basis to calculate the feed conversion ratio. Gut morphology was measured on days 21 and 42. Data were analysed using the General Linear Model procedures of the Statistical Analysis System.Bee pollen inclusion in starter diets had an effect (p<0.05) on body weight and live weight gain of male Ross 308 broiler chickens. The different inclusion levels of bee pollen had an effect (p<0.05) on the gut morphology of Ross 308 broiler chickens. The ileum lengths of female broiler chickens were significantly wider (p<0.05) in comparison with male chickens. This may suggest that bee pollen inclusion has a beneficial effect on broiler chickens gut morphology during the early stages of development. It can be concluded that natural substances such as bee pollen can be a possible feed additive to replace synthetic antibiotics, since such compounds are essential for the growth and development of poultry gut.(AU)

Growth Curve of Brazilian Creole Chickens (Canela-Preta Breed) Raised in Two Different Rearing Systems under Tropical Climate

The objective of this study was to describe the growth curve of Brazilian Creole chickens of the Canela-Preta breed raised in two different rearing systems using non-linear growth models. A total of 400 birds were divided into two groups of 200 animals (of both genders), which were kept in confined or semi-confined systems. The confined birds were housed in an experimental masonry shed and the semi-confined animals were housed in another shed with access to pasture from 29 days of age. Birds were individually weighed every seven days during six months for determination of the growth curves of body weight using 10 non-linear models. The parameters of the models were estimated using the Gauss Newton method. The performance of the models was assessed using mean squared error (MSE), coefficient of determination (R2), percentage of convergence, and residual mean absolute deviation (MAD). With the exception of the Inverse Polynomial, all the other models had R2 values close to one. Therefore, the best models were chosen based on the lowest MSE and MAD values, with the Richards model ranking first followed by the Von Bertalanffy model. Gender and rearing system effects significantly influenced (p<0.05) some parameters of the Richards model. In conclusion, the Richards model was the most adequate to describe the growth of Canela-Preta chickens. Gender and rearing system significantly influenced the growth of the birds. The growth rates observed indicated that management strategies can be performed to increase the production efficiency of Canela-Preta chickens.(AU)

Sealing strategies in corn silage and sheep performance in feedlots / Estratégias de vedação na ensilagem de milho e desempenho de ovinos em confinamento

The objective of this study was to evaluate the effects of different sealing strategies on aerobic stability and feed value of corn silage supplied to finishing lambs. The treatments were set up according to the silo sealing strategy: BP (black polyethylene film), BP + Bagasse (black polyethylene film + sugarcane bagasse) and BP + Silostop (Silostop® Orange oxygen barrier film + black polyethylene film). Six lambs per treatment were used, totaling 18 animals in an experimental period of 63 days. The silage from LP treatment presented the highest aerobic stability, however with lower dry matter digestibility coefficients. No significant differences were detected among treatments for intake and performance of lambs. But for final body weight, weight gain, daily average gain, feed efficiency and dry matter intake, the best results, in absolute value, were found for lambs fed with silage from LP + Bagasse treatment. The silage sealed exclusively with black polyethylene film showed greater aerobic stability. The different sealing strategies used in this experiment did not influence the performance of finishing Dorper x Santa Inês lambs.(AU)

Objetivou-se avaliar os efeitos de differentes estratégias de vedação sobre a estabilidade aeróbia e o valor alimentício da silagem de milho fornecida para cordeiros em terminação. Os tratamentos foram definidos de acordo com a estratégia de vedação do silo: LP (lona preta de polietileno), LP + Bagaço (lona preta de polietileno + bagaço de cana) e LP + Silostop (lona preta de polietileno + filme de barreira de oxigênio Silostop® Orange). Foram utilizados seis cordeiros por tratamento, totalizando 18 animais, em um período experimental de 63 dias. A silagem do tratamento LP apresentou maior estabilidade aeróbia, porém proporcionou menor coeficiente de digestibilidade da matéria seca. Não foi observada diferença significativa entre os tratamentos para o consumo e desempenho dos cordeiros. Todavia, para o peso corporal final, ganho de peso, ganho médio diário, eficiência alimentar e consumo de matéria seca, os melhores resultados, em valor absoluto, foram encontrados para os cordeiros alimentados com dieta à base da silagem coberta com LP + Bagaço. A silagem vedada exclusivamente com a lona preta de polietileno apresentou maior estabilidade aeróbia. As diferentes estratégias de vedação utilizadas nesse experimento não influenciaram o desempenho de cordeiros Dorper x Santa Inês em terminação.(AU)

Reproductive response of synchronized and extensively grazed Blackbelly ewes during the summer in the tropics

The present experiment aimed to evaluate the reproductive response of Blackbelly ewes synchronized with low doses of eCG during the summer in a tropical climate. Sixty multiparous hair ewes were divided into three groups (20 ewes/group): control group (CG; 0 IU of eCG), treated group 1 (TG-1; 140 IU of eCG) and treated group 2 (TG-2; 300 IU of eCG). The study found that the three groups of ewes showed differences in their reproductive behavior (P < 0.01). Indeed, all the ewes in the TG-1 and TG-2 groups presented a higher response to estrus than the CG (P < 0.01). In the same way, TG1 and TG-2 had an onset to estrus in less time (P < 0.01). On the other hand, prolificacy was also higher in TG-1 and TG-2 (P < 0.05). Likewise, ewes from TG-1 and TG-2 had more lambs than those from CG (P < 0.05). On the other hand, the variables of fertility and gestation length were similar regardless of the group of ewes (P > 0.05). It´s concluded that the ewes treated with eCG presented good reproductive behavior, and the majority did so in the first 24 to 36 h after removing the intravaginal device.