Stage-specific nutritional management and developmental programming to optimize meat production

Over the past few decades, genetic selection and refined nutritional management have extensively been used to increase the growth rate and lean meat production of livestock. However, the rapid growth rates of modern breeds are often accompanied by a reduction in intramuscular fat deposition and increased occurrences of muscle abnormalities, impairing meat quality and processing functionality. Early stages of animal development set the long-term growth trajectory of offspring. However, due to the seasonal reproductive cycles of ruminant livestock, gestational nutrient deficiencies caused by seasonal variations, frequent droughts, and unfavorable geological locations negatively affect fetal development and their subsequent production efficiency and meat quality. Therefore, enrolling livestock in nutritional intervention strategies during gestation is effective for improving the body composition and meat quality of the offspring at harvest. These crucial early developmental stages include embryonic, fetal, and postnatal stages, which have stage-specific effects on subsequent offspring development, body composition, and meat quality. This review summarizes contemporary research in the embryonic, fetal, and neonatal development, and the impacts of maternal nutrition on the early development and programming effects on the long-term growth performance of livestock. Understanding the developmental and metabolic characteristics of skeletal muscle, adipose, and fibrotic tissues will facilitate the development of stage-specific nutritional management strategies to optimize production efficiency and meat quality.

Beneficial impact of dietary methyl methionine sulfonium chloride and/or L-carnitine supplementation on growth performance, feed efficiency, and serum biochemical parameters in broiler chicken: role of IGF-1 and MSTN genes

The purpose of this study was to examine the effect of dietary supplementation with methyl methionine sulfonium chloride (MMSC), and L-carnitine (L-CAR) alone or in combination on the growth performance of broilers through their impact on the expression of IGF-1 and MSTN genes associated with growth in broilers. One-day-old female Ross 308 broiler chicks were allocated into four groups, each of which received a broiler starter diet and water daily ad libitum. The control group (group 1) was given drinking water without any additives. Group 2 received 0.25 g L-carnitine per liter of drinking water, group 3 received 0.25 g MMSC per liter of drinking water, and group 4 received 0.25 g of both L-carnitine and MMSC per liter of drinking water. Birds were given a starter diet to 21 days after which they received a broiler grower diet to 35 days when the experiment ended. There were five replicate groups of 12 birds per treatment. Body weights and feed intake were recorded weekly. Compared to the control group of birds, supplementation with MMSC either alone or in combination with L-carnitine resulted in an increase in growth rate or feed utilization efficiency; L-carnitine by itself had no effect. MMSC supplementation, again either alone or in combination with L-carnitine, increased jejunal and ileal villi height, increased serum total proteins and globulins, downregulated myostatin (MSTN) mRNA, and upregulated insulin growth factor-1 (IGF-1) mRNA expression. Supplementation with L-carnitine alone showed none of these effects. We conclude that MMSC supplementation improved growth performance through the upregulation of IGF-1 mRNA expression and downregulation of MSTN mRNA expression.

The effect of feeding adequate or deficient vitamin B6 or folic acid to breeders on methionine metabolism in 18-day-old chick embryos

Three isotopic tracers ([2,3,3-²H₃]-L-serine, [²H₁₁]-L-betaine, and [1-¹³C]-L-methionine) were administered by amnion injection into 18-day-old chick embryos to investigate the kinetics of methionine metabolism. The embryos utilized were from eggs collected from 34-week-old Cobb 500 broiler breeders that were fed either a control diet containing folic acid (1.25 mg/kg diet) and pyridoxine HCl (5 mg/kg diet) or diets devoid of supplemental pyridoxine or folic acid. Intermediate metabolites of methionine metabolism and polyamines were analyzed in 18-day-old chick embryos. There were no differences in hepatic [²H₂] methionine or [²H₃] cysteine enrichments or in physiological concentrations of sulfur amino acids for chick embryos from breeders fed the control diet and embryos from breeders fed diets containing no pyridoxine or folic acid. Supplementation of B₆ or folic acid did not affect the production of methionine and cysteine in chick embryos. However, breeders fed the control diet with both folic acid and pyridoxine supplementation produced embryos with a two-fold reduction of hepatic homocysteine and increased spermine compared with embryos from breeders fed diets containing no supplemental pyridoxine or folic acid (P < 0.05). Hepatic S-adenosylmethionine for embryos from breeders fed no supplemental B₆ was half the concentration compared with embryos from breeders fed the control diet. Embryos from breeders fed the control diet were utilized to determine the proportion of homocysteine going through remethylation and transsulfuration and also to determine the pathway of remethylation. Sixty-five percent of the methyl groups used for homocysteine remethylation from control embryos was via the MFMT pathway. Alternatively, 61% of homocysteine from control embryos was remethylated via the MFMT and the BHMT reactions and 39% of homocysteine was catabolized to cysteine via the transsulfuration pathway. These data show that in embryos, intermediate metabolites of methionine and polyamines increase in concentration when pyridoxine levels are provided in deficient concentrations to the breeder hen. In addition, this research demonstrates that folic acid deficient embryos conserve methionine, rather than catabolize it to cysteine.

Influences of vitamin A, L-carnitine, and folic acid in ovo feeding on embryo and hatchling characteristics and general health status in ducks

The current investigation was conducted to test the potential effects of in ovo feeding of vitamin A, L-carnitine, and folic acid on embryonic growth and post-hatch performance. A total of 450 fertile duck eggs were randomly distributed into two experiments of five groups/experiment (255 eggs/experiment and 45 egg/group). The experimental groups were: negative control (non-injected eggs), positive control (eggs were injected with 0.1 ml sterile deionized; DI water/egg), and three other treatments in which vitamin A, L-carnitine, and folic acid were injected (1 mg of each nutrient dissolved in 0.1 ml sterile DI water/egg). All-in ovo injected groups with vitamin A, L-carnitine, and folic acid increased the embryo weight, residual yolk weight, heart weight, hatchability percentage, and embryo length at the 25th day of incubation. At hatching, all micronutrients-in ovo injected treatments increased the duckling's weight, levels of blood hemoglobulin, plasma triiodothyronine, and thyroxin, insulin-like growth factor1, total protein, albumin, and globulin, compared with the controls in both experiments. Conclusively, the in ovo feeding of the present micronutrients showed positive impacts on embryonic development, hatchling health status of ducklings.

Effects of In Ovo Injection of Coenzyme Q10 on Hatchability, Subsequent Performance, and Immunity of Broiler Chickens

Effects of in ovo injection of Q10 on hatchability, performance (feed intake (FI), body weight gain (BWG), feed/gain ratio (F/G)) traits, and immune status of Ross × Ross 308 broiler chicks, hatched from eggs laid by a 38-week-old breeder flock, were determined through 42 days after hatch. Eggs containing live embryos were injected in the amnion with 0.1 and 0.2 mL Q10 solution on day 18 of incubation. Two controls groups were included as sham and/or as an uninjected group. At 28 and 42 days of age, performance traits, serum enzyme activity, weights of immune organs, and serum antibody titer of viral diseases were determined. Results were shown that hatchability % increased by Q10 on average of 6.54% (P≤0.025) and body weight/egg weight after hatching increased up to 4.74% (P≤0.002), compared with uninjected and sham controls. Injection of Q10 at different levels led to significant increases (P≤0.001) in performance traits all over the rearing period (P<0.05). Weight of immune organs significantly improved compared to uninjected and sham controls (P<0.05). In addition, serum antibody titers of viral diseases as well as serum enzyme activity of AST, ALT, CAT, and SOD were significantly changed by Q10 treated groups than controls (P≤0.01). In conclusion, in ovo injection of Q10 at levels of 0.1 and 0.2 mL led to significant increases in hatchability%, internal egg characteristics, and performance parameters as well as serum enzyme activity, weight of immune organs, and serum antibody titer of ND, AI, and IBD diseases.

In ovo applications in poultry: A review,

The various methods employed for the in ovo administration of different materials for promoting the health and productivity of poultry are discussed in this review article. The amnion has proven to be an effective site for injection and the timing of in ovo injection has commonly occurred at transfer. However, the volumes and dosages or concentrations of the materials administered vary depending on bird type, egg size, timing and site of injection, incubation system and regimen, and the type of material. Both manual and automated injections have been shown to be effective. Nevertheless, commercial application mandates automation. Materials described in the literature over the past 20 years or more for in ovo use in avian species include vaccines, drugs, hormones, competitive exclusion cultures and prebiotics, and supplemental nutrients. Vaccines approved for in ovo delivery include those for Marek's disease, infectious bursal disease, fowl pox, Newcastle disease, and coccidiosis. Some of the materials listed above have been shown to be viable candidates for enhancing immunity and for promoting embryonic and posthatch development. Several reports have indicated that probiotics may be effectively used to fight intestinal bacterial infections, and folic aid, as well as egg white protein and various amino acids, including L-arginine, L-lysine, L-histidine, HMB, and threonine alone or in combination, have been shown to benefit embryonic development or posthatch performance. Furthermore, CpG oligodeoxynucleotides, vitamins C and E, and thyme and savory have the potential to enhance immunity, carbohydrates can be used to increase tissue glycogen stores, and creatine can be used to promote muscle growth. Trace minerals and vitamin D3 have shown potential to improve bone strength, and potassium chloride may be an effective alternative electrolyte in vaccine diluent. The in ovo application of these and other materials will continue to expand and provide further benefits to the poultry industry.

Effect of Different Dietary Levels of Atorvastatin and L-Carnitine on Performance, Carcass Characteristics and Plasma Constitutes of Broiler Chickens

The effects of L-carnitine, atorvastatin and their combination on growth and lipid metabolism of broiler chickens is not yet known. Thus, the objective of the present study was to investigate the effects of dietary L-carnitine and atorvastatin on the performance, carcass characteristics and blood parameters in broilers. Different dietary levels of L-carnitine (0, 150 and 300 mg/kg, respectively) and atorvastatin (0, 1 and 2 g/kg, respectively) were added to the daily birds' ration. Significant positive effects (P<0.05) on broiler body weight for both L-carnitine and atorvastatin were reported, and this effect became clear starting from the 4th week of rearing period till the slaughter age. Dietary treatments had also significant (P<0.05) positive effects on broilers empty carcass, breast and drumstick weights. Conversely, L-carnitine slightly increased abdominal fat, whereas supplementing atorvastatin slightly reduced it (P<0.05). However, Combining the treatments, resulted in reduction of abdominal fat pad, showing also the best development of breast and drumstick muscles (P<0.05). Moreover, the weight of gizzard, liver and heart were significantly higher in birds treated with the highest doses supplied (P<0.05). Dietary treatments had also influence on blood biochemical parameters of broilers. In overall, our findings suggest that combining dietary L-carnitine and atorvastatin supported birds growth and muscles development reducing the body fat deposition. However, further studies are needed to deeply study the potential effect of statins on meat quality.

Effects of dietary soybean and sunflower oils with and without L-carnitine supplementation on growth performance and blood biochemical parameters of broiler chicks

Abstract. An experiment was designed to investigate the effects of soybean, sunflower oil and dietary L-carnitine supplementation on growth performance, some blood biochemical parameters and antibody titer against Newcastle disease of broiler chicks. A 5-week feeding trial, 240 1-day old male broiler chicks (Ross 308) were randomly allocated to six dietary treatments as a 3 × 2 factorial experimental design where three sources of dietary oil contained soybean, sunflower and soybean plus sunflower oil with and without 120 mg kg−1 of L-carnitine supplementation in the diet. Results showed that soybean oil with L-carnitine significantly improved body weight gain and feed conversion ratio of broiler chicks in the grower and total period of rearing (p < 0.05). L-carnitine supplementation significantly increased total protein, globulin, cholesterol, HDL and LDL (high- and low-density lipoprotein) of blood serum in broiler chicks (p < 0.05). L-carnitine supplementation increased antibody titer against Newcastle disease of chicks and the highest levels were observed in those with the supplement of L-carnitine in the soybean oil dietary treatment. Results of this experiment showed that the growth performance and blood biochemical responses of broiler chicks to dietary supplementation with L-carnitine in dietary oil source and soybean oil, in comparison to sunflower oil, is the better plant oil for growth and immunological performance of broiler chicks.

Nutrition and metabolism in poultry: role of lipids in early diet

Modern strains of broiler chickens are selected for fast growth and are marketed anywhere from 36 to 49 days after a 21-day incubational period. For a viable healthy chick, all the necessary nutrients required for growth and development must be provided by the hen through the fertilized egg. The current feeding strategies for improved growth, health and productivity are targeted towards chicks after hatching. Considering the fact that developing chick embryo spends over 30 % of its total life span inside the hatching egg relying on nutrients deposited by the breeder hen, investigations on nutritional needs during pre-hatch period will improve embryonic health, hatchability and chick viability. In this context, investigations on hatching egg lipid quality is of utmost importance because, during incubation, egg fat is the major source of energy and sole source of essential omega-6 (n-6) and omega-3 (n-3) fatty acids to the chick embryo. Due to the unique roles of n-3 and n-6 fatty acids in growth, immune health, and development of central nervous system, this review will focus on the role of early exposure to essential fatty acids through maternal diet and hatching egg and its impact on progeny in meat-type broiler chickens.

Physiological relationships of the early posthatch performance of broilers to their embryo and eggshell characteristics

Relationships between physiological parameters of early posthatch chicks with their corresponding egg and embryo parameters were examined in progeny of young broiler breeders. Four hundred and 80 broiler hatching eggs that were obtained from a 29-wk-old Ross 308 breeder flock were incubated on 8 replicate tray levels of an incubator until hatch. Between 10.5 and 18.5 d of incubation, internal (T(emb)) and external (T(ext)) egg temperatures were recorded twice daily using temperature transponders. Beginning at 18.5 d, the eggs were individually monitored for hatch every 12 h. Average T(emb), T(ext), and average daily incubational egg weight loss (EWL) for the 10.5- to 18.5-d incubation period were used to calculate eggshell water vapor conductance (G(H2O)), specific G(H2O) (g(H2O); G(H2O) adjusted to 100 g of set egg weight basis), and a G(H2O) constant (K(H2O)) for each egg. Chicks were grown out for 10 d in pens of a single battery brooder. In each pen, on d 3 posthatch, carcasses, yolk sac, liver, and pipping muscle samples were collected from at least 2 chicks that hatched from eggs implanted with transponders for determination of their relative weights and moisture concentrations. Livers and pipping muscles were also analyzed for glucose, glycogen, fat, and protein concentrations. Yolk sac weight as a percentage of chick BW (YW) and its moisture concentration (YSM) were positively correlated with T(emb). Egg g(H2O) was positively correlated with chick carcass moisture concentration and its relative weight as a percentage of set egg weight, but it was negatively correlated with YW. The positive functional relationship between T(emb) and incubation length may be mediated via their common positive relationships to YSM. A negative correlation was observed between percentage EWL and relative BW on d 0 and 0.5 posthatch for chicks hatched from unimplanted eggs. The results suggest that a higher g(H2O) results in an increased metabolism of the broiler embryo, which subsequently increases growth and yolk sac absorption in broiler chicks through 3 d posthatch.

Effects of in ovo injection of carbohydrates on somatic characteristics and liver nutrient profiles of broiler embryos and hatchlings

Effects of the in ovo injection of commercial diluent supplemented with dextrin or with dextrin in combination with various other carbohydrates on the somatic characteristics and liver nutrient profiles of Ross × Ross 708 broiler embryos and chicks were investigated. Results include information concerning the gluconeogenic energy status of the liver before and after hatch. Eggs containing live embryos were injected in the amnion on d 18 of incubation using an automated multiple-egg injector for the delivery of the following carbohydrates dissolved in 0.4 mL of commercial diluent: 1) 6.25% glucose and 18.75% dextrin; 2) 6.25% sucrose and 18.75% dextrin; 3) 6.25% maltose and 18.75% dextrin; and 4) 25% dextrin. Also, a noninjected control and a 0.4-mL diluent-injected control were included. Body weight relative to set egg weight on d 19 of incubation (E19) was increased by the injection of all carbohydrate solutions, and on the day of hatch was increased by the injection of diluent, sucrose and dextrin, and maltose and dextrin solutions. Hatchability of the fertilized eggs, residual yolk sac weight, and liver weight were not affected by any injection treatment; however, as compared with the 0.4 mL diluent-injected group, all of the supplementary carbohydrates, except for the glucose and dextrin combination group, increased liver glycogen and glucose concentrations on E19. Furthermore, all carbohydrates, except for the 25% dextrin treatment, decreased liver fat concentration on E19. From E19 to the day of hatch, liver glycogen concentrations dropped dramatically from an average of 3.2 to 0.6%. Despite treatment differences observed on E19 for liver glycogen, glucose, and fat concentrations, these differences were lost by the day of hatch. Nevertheless, liver glycogen and glucose concentrations were positively correlated on the day of hatch. In conclusion, the in ovo injection of various supplemental carbohydrates dissolved in 0.4 mL of commercial diluent altered the liver nutrient profile of Ross × Ross 708 broiler embryos before hatch. However, the subsequent pattern of energy utilization during the hatching process modified these effects.

Effects of in ovo injection of carbohydrates on embryonic metabolism, hatchability, and subsequent somatic characteristics of broiler hatchlings

The effects of the in ovo injection of different carbohydrate solutions on the internal egg temperature (IT), hatchability, and time of hatch of embryonated Ross × Ross 708 broiler hatching eggs were determined. In addition, the BW, liver weight, yolk sac weight (YSW), and yolk-free BW (YFBW) of the embryos on d 19.5 of incubation and of the chicks on day of hatch were determined. Eggs containing live embryos were injected in the amnion on d 18.5 of incubation using an automated multiple-egg injector. Solution injections delivered 1.2 mL of physiological saline (0.85%) alone or with a supplemental carbohydrate. The following supplemental carbohydrates were separately dissolved in saline at a concentration of 0.3 g/mL: glucose, fructose, sucrose, maltose, and dextrin. Temperature transponders were implanted in the air cells of embryonated and nonembryonated eggs after in ovo injection for the detection of IT at 6, 14, and 22 h after injection. The IT of embryonated eggs was significantly greater than that of nonembryonated eggs at all 3 times after the treatment period. Eggs that were injected with saline with or without supplemental carbohydrates experienced a reduction in IT when compared with control eggs whose shells were perforated without solution delivery, and the decrease in IT was associated with a delay in hatch time. Liver weight was negatively related to YSW and positively related to YFBW, and YSW was negatively related to YFBW. Although the saline and carbohydrate solution injections increased chick BW compared with noninjected controls, chick YFBW was decreased in the maltose- and sucrose-injected groups. In conclusion, the injection of 1.2 mL of saline with or without supplemental carbohydrates lowered embryonic metabolism, as reflected by a lower IT and a delay in time of hatch. However, effects of the different carbohydrate solutions on yolk absorption and tissue deposition in yolk-free embryos varied. These results suggest that lower volumes for solutions containing maltose, sucrose, or fructose should be considered for in ovo injection.

Effects of commercial in ovo injection of carbohydrates on broiler embryogenesis

The effects of in ovo injection of different carbohydrate solutions on hatchability of fertilized eggs (HF), rate of hatch, BW, body moisture, yolk sac weight, and yolk sac moisture of Ross × 708 broiler chicks, hatched from eggs laid by a 34-wk-old breeder flock, were investigated. Eggs containing live embryos were injected, using an automated multiple-egg injector, in the amnion on d 18.5 of incubation with 0.1, 0.4, 0.7, or 1.0 mL of commercial diluent or a carbohydrate dissolved in diluent. The commercial diluent containing 0.25 g/mL of one of the following carbohydrates was injected into eggs: glucose, fructose, sucrose, maltose, or dextrin. The results showed that no carbohydrate type or solution volume affected rate of hatch. Absolute and proportional BW on day of hatch were positively related to injection volume (P < 0.001). However, HF was negatively related to injection volume (P < 0.001). To realize an HF of 90%, the injection volume could not exceed 0.4 mL for fructose or sucrose and could not exceed 0.7 mL for glucose, maltose, or dextrin. Yolk-free BW was negatively related to injection volume of fructose and sucrose (P < 0.004), but was not related to injection volume of diluent, glucose, maltose, and dextrin. Conversely, absolute and proportional yolk sac weights were positively related to injection volume of fructose, sucrose, and dextrin (P < 0.01), but were also not significantly related to injection volume of diluent, glucose, and maltose. Yolk sac moisture was positively related to injection volume for all injectables, including the diluent (P < 0.03). However, body moisture and yolk-free body moisture were not related to injection type or volume. In conclusion, the use of carbohydrates added to a commercial diluent for the in ovo injection of broiler hatching eggs requires the use of appropriate volumes to promote growth and nutrient utilization without adversely affecting HF.