MJ ME Research Articles

Effect of feeding system on growth and carcass characteristics of Improved Jezersko-Solčava lambs

The objective of this study was to evaluate the effect of feeding system on growth and carcass characteristics of Improved Jezersko-Solčava (JSR) weaned lambs. Thirty-five lambs (25.48 kg) housed in group pens were divided into four groups and offered different diets which consisted of hay and second harvest in the ratio of 40:60 and a supplement of 650 g concentrate (Diet 1), hay and second harvest in the ratio of 40:60 (Diet 2), hay and 650 g of concentrate (Diet 3), and just hay (Diet 4) for 50 days. Daily intake was calculated by weighting the offered amount and leftovers of concentrate and forage. Daily intake per lamb contained 15.56 MJ, 14.38 MJ, 16.57 MJ, and 12.23 MJ ME for the Diet 1, 2, 3, and 4, respectively. Lambs were slaughtered at 30.77 kg of live weight. Lambs fed Diet 1 reached the highest DG (165.5 g/day), followed by Diet 3 (146.89 g/day), Diet 2 (123.55 g/day) and Diet 4 (75.51 g/day). HCW and CCW were higher in Diet 1 and 3, compared to Diet 2 and 4. Lambs fed Diet 3 had the highest DP (45.35%), followed by Diet 1, 2, and 4 with 44.33, 41.10 and 39.51%, respectively. The lowest kidney-pelvic fat was observed in lambs fed Diet 4 (5.64) and the highest in Diet 3 (7.66). These results demonstrate that fattening of weaned JSR lambs fed by forage-concentrate diets produced heavier carcasses than those only fed by forage, without significant effects on carcass fatness or carcass conformation.

Captive behavioural patterns of the red-necked ostrich

Purpose: This study was conducted to evaluate captive ostrich behavioural patterns during the laying season. Design/methodology/approach : The parent red-necked ostrich (Struthio camelus camelus) flock (5 males and 7 females) was stocked from the wild (Dindir National Park) and accommodated in one breeding pen. The feeding plan was 14% crude protein and 09.23 MJ ME/ Kg. Behaviour was

Nutritional evaluation of five species of forage brassica

Despite a growing interest in ruminant nutrition and the ongoing, widespread use of forage brassicas, there is an absence of data that adequately describe the nutritional value of modern brassica cultivars in New Zealand. Five forage brassica species represented by 30 cultivars were evaluated in single-site, single-year trials in the South Island. Replicated plots of leafy turnips, bulb turnips, rape, swede and kale were harvested at 53, 91, 98, 181 and 186 days after sowing, respectively. Whole plants were dissected to leaf, stem and bulb and/or petiole and components assessed for nutritive value. Quality differed significantly among and within brassica species. Within species, percent dry matter (DM) was consistent for rape, bulb turnip and leaf turnip, but differed significantly among cultivars in kale and swede. Mean metabolisable energy (MJ ME) content at harvest was highest for swede (13.8 MJ ME/ kg DM) and lowest for kale (11.2 MJ ME/kg DM). For all brassica species, fibre content as estimated by neutral detergent fibre (NDF) content was below optimum for ruminal function, highlighting the importance of high NDF supplementary feeds for brassica-fed stock. For some but not all brassica species, nutritive value may be modified by cultivar selection however factors not investigated in this study including sowing rate and time from sowing to harvest remain important potential moderators of forage brassica quality. Keywords: Forage brassica, leafy turnip, bulb turnip, forage rape, swede, kale, nutritive value, feed testing

Nutritional Management of Transition Dairy Cows

Nutrition and management during late gestation impact peripartal health problems and influence subsequent milk production. Obesity at calving is a known risk factor for health problems and suboptimal production. Our evidence indicates that higher energy-density close-up diets do not increase subsequent milk production or energy balance. Our data indicate that even modest overfeeding results in changes analogous to obesity, with elevated insulin and NEFA and poor dry matter intake before calving, but substantial body fat mobilization, increased liver fat deposition, and prolonged increases in blood ketone bodies after calving. Modest energy excess during the dry period can lead to substantial internal fat deposition even without detectable changes in body condition. We conclude that requirements for energy (and other nutrients) should be met but not greatly exceeded during the dry period. This can be achieved by limit-feeding of moderate-energy diets or ad libitum feeding of high-roughage low-energy diets. Requirements for energy for dry cows and first-gestation heifers are modest (ca. 100 MJ ME or 14 Meal NE per cow daily) and can be met with relatively low-energy diets. Conversely, diets high in starch from corn silage or whole-crop cereals and supplemented with additional concentrates result in excess energy intake relative to requirements, as cows do not regulate intake to meet energy needs over the short-term. Dilution of those diets with low-quality roughages such as cereal straws can control energy intake to near cow’s requirements. Careful feeding management is critical to ensure that formulated nutrient intakes are actually achieved in practice.

The Response of Male Indigenous Venda Chickens to Diet Energy to Protein Ratios Fed from Seven up to 13 Weeks of Age

An experiment was conducted with the objective of determining the response of male indigenous Venda chickens to varying energy to protein ratio fed from seven upto 13 weeks of age. The experimental design was completely randomized and a quadratic type equation was used to determine ratios for optimum production variables. The results indicate that a single dietary ener gy to protein ratio of 66 MJ ME/ kg protein supported optimum growth rate, live weight, carcass weight and fat pad weight. Dietary ener gy to protein ratios of 74, 65, 73, 71 and 62 MJ ME/ kg protein supported optimum feed intake, Feed feed conversion ratio, metabolisable ener gy intake, nitrogen retention and breast meat yield respectively., in indigenous male Venda. However, no single dietary energy to protein ratio optimized all the production variables under study. This may imply that the nutrient requirements of male indigenous Venda chickens are dependent on the particular production variable in question.

A Feed Serine Protease Improves Broiler Performance and Increases Protein and Energy Digestibility

Effects of a novel serine protease, RONOZYME® ProAct (RPA) on protein solubilisation, hydrolysis and digestibility were tested in a gut simulation model. Furthermore, the effects of RPA (supplemented at 15,000 PROT/kg feed) on growth performance and nutrient digestibility were tested in two in vivo broiler experiments each arranged in a 2×2 factorial design (enzyme x sex in experiment 1 and enzyme x protein level in experiment 2). Each dietary treatment had 12 replicates. In experiment 1, birds were fed 12.7 MJ ME per kg iso-energetic diets in 2 phases. Each diet was fed without or with RPA (C or C+RPA, respectively) to either males or females. In experiment 2, two diets were fed in four treatments. Diet 1 (211 and 200 g CP per kg feed in the starter and grower phases respectively) was fed without or with RPA (NP or NP+RPA, respectively). Diet 2 (200 and 190 g CP per kg feed in the starter and grower phases respectively), was fed without or with RPA (LP or LP+RPA, respectively). At the end of each experiment, eight male birds per treatment were randomly selected and used for ileal digestibility measurements. In vitro, RPA significantly increased the degree of protein hydrolysis, solu-bilisation and digestibility. In males, C+RPA was significantly better than C in WG (2,393 g vs. 2,262 g) and FCR (1.60 vs. 1.65). In females, C+RPA was better than C in FCR (1.37 vs. 1.39) in the starter phase. The FCR of LP+RPA was significantly better than LP. In experiment 1, RPA significantly increased ileal protein (82.8% vs. 76.9%) and energy (77.8% vs. 70.6%) digestibilities. In LP, RPA significantly improved energy digestibility (76.6% vs. 75.5%). These results suggest that RPA can improve broiler performance by enhancing protein and energy digestibility.

Effects of extra feeding in mid-pregnancy for three successive parities on lean sows’ productive performance and longevity

The aim of this study was to investigate the long-term effects of increasing feeding allowance during mid-pregnancy in sows. A total of 103 PIC pregnant sows (mixed parity) were allocated to two treatments: control (C, n = 49) were fed 2.5-3.0 kg d-1 (12.1 MJ ME kg-1) and extra-fed (E, n = 54) received +2.0 kg d-1 of the same feed from day 45 to 85 of gestation over three consecutive cycles. Body weight, backfat thickness (BF) and loin depth were measured on days 45 and 85 of gestation, farrowing and weaning. Litter and sows performance were recorded during lactation and post-weaning. Overall culling rates were 61 and 67% for C and E groups, respectively. After three cycles, E sows showed a positive BF balance in contrast to C sows (E = +1.46 mm and C= -1.81 mm, P < 0.05). In cycle 3, E sows presented greater piglet birth weights than C sows, being mainly evident in sows that were nulliparous at the onset of the experiment (P < 0.05). Extra-fed sows showed a greater incidence of mastitis-metritis-agalactia syndrome than C sows (P = 0.003). Thus, increasing feeding allowance during mid-pregnancy positively affected BF balance and birth weight in nulliparous, but impaired the sows’ ability to produce milk in the long-term.

Effect of weaning age on feed intake and ruminal fermentation patterns of calves fed a dry total mixed ration with ad libitum access to grass hay

To study the effect of weaning age on average daily gain (ADG), dry matter intake (DMI) and ruminal fermentation, 10 rumen-cannulated male Holstein calves were randomly assigned to one of two treatments: (i) early weaned at 8 weeks of age (235 l milk); (ii) conventionally weaned at 12 weeks of age (347 l milk). Twice daily grass hay (9.0 MJ ME · kg−1 DM) and a dry total mixed ration (TMR) (11.6 MJ ME · kg−1 DM) containing 15% alfalfa hay and 85% concentrates were offered separately. Water was available ad libitum. Ruminal fluid was collected via cannulas at weeks 9, 11, 13 and 15, twice weekly just prior to as well as 1, 3, 5 and 7 h after morning feeding. Calves of both treatments achieved adequate ADG (947 vs. 959 g; p > 0.05). Just-weaned calves rapidly increased DMI (1.1–2.5 kg TMR and 2.4–3.6 kg TMR for early- and conventionally-weaned calves, respectively). From weeks 10–12 early-weaned calves consumed significantly more dry feed than conventionally-weaned calves (week 10: 2.5 vs. 1.6 kg/d; week 12: 3.4 vs. 2.4 kg/d). Early weaning stimulates DMI supporting ruminal fermentation intensity, indicated by lower ruminal pH. After weaning, only early-weaned calves achieved critical average ruminal pH (week 9: 5.7 vs. 6.0, p = 0.017; week 11: 5.9 vs. 6.2, p = 0.007). Experimental treatment did not affect the concentration of ruminal short-chain fatty acids (SCFA). For all calves, the effects of the concentrate-rich TMR were shown by a high SCFA level (daily average: 137–152 mmol · l−1) and an acetate to propionate to butyrate ratio between 51:36:9 and 54:33:10.

Feed conversion rate and estimated energy balance of free grazing Iberian pigs

A direct in situ observation method has been used, observing ingestive bites taken by continuously monitored Iberian pigs (10 uninterrupted hours, from 08:30 to 18:30) to calculate intake of acorns and grass and grazing activity during the fattening period in the dehesa (cleared Mediterranean forest like savannah) from November first to the end of December. The obtained results, together with measurements of weight gain, have been used to propose a new method for calculating stocking rate capacity. 60 grazing days have been studied corresponding to different randomly chosen Iberian pigs (110.2 ± 1.3 kg of average initial LW) during 2 months. The results show a daily intake of 56.4 ± 2.34 MJ ME from grass and acorns, of which acorns accounted for 90.42% (2.92 ± 0.13 kg of kernel DM and 0.49 ± 0.04 kg of grass DM); to do so pigs walk 3.9 ± 0.18 km in 369.0 ± 7.8 min of activity which happens at an average temperature of 7.6 ± 0.2 °C. The daily expenditure of ingested energy is divided as follows: 13.8 ± 0.18 MJ for the resting metabolism (54.1% ± 0.44); 5.5 ± 0.14 MJ for thermoregulation (21.5% ± 0.29); 6.3 ± 0.15 MJ for grazing, divided in displacement (8.0% ± 0.32) and standing (16.4% ± 0.25) during the activity. The total energy cost is therefore 25.7 ± 0.38 MJ ME, which equals 51.2% ± 2.71 of the ingested ME. ME available for production was 30.7 ± 2.33 MJ per pig and day, equivalent to 0.8 ± 0.06 MJ/kg LW 0.75 per day. The total heat losses were 31.8 ± 0.59 MJ per pig and day. The corresponding ratios are: 253.0 ± 13.05 g/kg DM for gain/feed, 15.3 ± 0.79 g/MJ for gain/ME intake and 1.4 ± 0.06 MJ/kg LW 0.75. There are not significant differences between both sexes. With an average daily weight gain of 0.79 ± 0.03 kg, the conversion rate of the ME consumed as grass and acorns is 56.4 ± 2.34 MJ ME (corresponding to 4.0 ± 0.29 Kg kernel DM and 0.7 ± 0.08 kg of grass DM). To ingest that amount of energy pigs have to use 10.5 ± 0.75 kg of entire acorns to shell these. Bearing in mind that the annual production of acorns of an average adult evergreen oak ( Q. ilex rotundifolia) acorn production is very close to this amount, it could be established that pig feed conversion rate (FCR) for acorn equals the total acorn production from one adult tree. So stocking rate may be estimated by dividing the number of adult oaks of a dehesa by the expected weight gain; and it could be established that stocking rate should be < 1pig/ha of dehesa to gain the minimum standard of 46 kg only grazing natural resources.

THE EFFECT OF GENOTYPE ON RESPONSE IN BODY COMPOSITION TO VARIATION IN DIETARY PROTEIN : ENERGY RATIOS

An experiment with 480 day-old chicks of four commercial strains was conducted to study theeffect of genotype on response in body composition to variation in dietary protein: energy ratios. Thechicks were randomly allocated into 4x2x4 factorial and fed on a commercial starter diet (250 g CP and12.5 MJ of ME /kg) from hatching to 5 d of age and divided into two groups with three replicationseach of 16 birds and given either the such starter diet (S) or a finisher diet (F) containing 190 g CP and13.0 MJ of ME /kg. The birds were reared in strain-and sex-intermingled groups in brooders and followoncages until they reached the target body weight of 600-650 g (females) or 650-700 g (males) andtransferred to single cages and fed S or F diet until 1200-1300 g (females) or 1300-1400 g (males). Thelighting program was 23 h light for the first two days, and reduced to 18 h/d for the remainder of theexperiment. There were considerable variations in relative growth performance, FCR, carcass fat andabdominal fat due to genotypes and dietary regimen. Although birds tend to response in similar waywhen dealing with the excesses and insufficient supply, the nutrient requirements in relation to theprotein: energy ratios should be designed according to genetic background.The accumulation of fatduring the growing period was primarily due to the genetic variation whereas beyond this age, variationin abdominal fat was due principally to dietary effects.

Effect of different dietary energy levels on the reproductive performance of Kivircik sheep under a semi-intensive system in the South-Marmara region of Turkey

The objective of the study was to determine the effects of four dietary energy levels (L 1 - 10.3, L 2 - 11.0, L 3 - 11.6 and L 4 - 12.2 MJ ME per kg DM) on oestrus synchronization and fertility in Kivircik ewes. Eighty Kivircik ewes were randomly allocated in equal numbers to the four dietary energy treatments. The groups were treated with intra vaginal sponges containing 40 mg FGA (fluorogestone acetate) for a period of 14 days and 500 IU pregnant mare serum gonadotropin was injected intramuscularly after sponge withdrawal. The proportion of ewes exhibiting overt oestrus within 96 h after the injection was significantly lower (P<0.05) in the L 1 and L 2 eves (86 and 89 %) than in those on the L 3 (100%) and L 4 (100%) treatments, respectively. Mean litter size and fecundity were higher (P<0.05) in the L 3 (1.95) and L 4 (2.05) compared with the L 1 (1.45 and 1.25) and L 2 (1.63 and 1.55) ewes. It is concluded that shortterm (21 days) in the level of dietary energy supplementation pre-mating can have a beneficial effect on reproductive performance in ewes.

Effect of Maternal Undernutrition during Late Pregnancy on Growth and Development of Ovine Fetal Visceral Organs

This study investigated the effect of maternal undernutrition during late pregnancy on the growth and development of ovine fetal visceral organs. One hundred Mongolian ewes were mated at a synchronized oestrus and divided into three groups and offered 0.175 MJ ME kgw -0.75 d -1 (Restricted Group1; RG1), 0.33 MJ ME kgw -0.75 d -1 (Restricted Group2; RG2) and ad libitum access to feed (Control Group; CG) during late pregnancy (90 days). Selected animals in each group were slaughtered immediately at d 90 of pregnancy and after parturition (neonatal lambs), and major visceral organs were removed and weighed separately. The results indicated that the weights of lung (p<0.01), spleen (p<0.01), heart (p<0.05), liver (p<0.05) and abomasum (p<0.01) in RG1 were significantly lighter than those of CG. For RG2, only the weights of the lung (p<0.05) and spleen (p<0.01) were significantly lighter than those of CG; when expressed as a percentage of body weight, significance was retained in the spleen (p<0.01) for both restricted groups, but the percentage of brain in RG1 was significantly higher than that in CG (p<0.01). For lung and spleen, the amount of DNA was significantly lower (p<0.01) in both groups of restricted neonatal lambs compared to CG; however, there was a significant difference only between RG1 and CG for protein: DNA ratio (p<0.01). The DNA content of kidney, abomasum and jejunum were decreased (p<0.05) in RG1 neonatal lambs,but protein: DNA ratio in the liver was decreased compared with that of CG (p<0.05). The plane of maternal undernutrition during late pregnancy had a significant effect on the growth and development of fetal visceral organs, which altered ontogeny of fetal organ growth and development. These perturbations in fetal visceral development may have significant implications on postnatal growth and adult health. (Key Words : Ewe, Undernutrition, Fetal Visceral Organs, Growth and Development)

Physical composition, primary cuts and meat cuts of carcasses from Zebu and Bos taurus X Bos indicus crossbred cattle

Data on hot carcass weight, hot carcass yield, hindquarter weights and physical components, forequarter and spare ribs, and the weights of the main commercial cuts from the hindquarters of twenty young intact bulls were assessed. The animals, belonging to four genetic groups (Nellore, ½ Guzerath + ½ Nellore (½ G + ½ N), ½ Red Angus + ½ Nellore (½ R + ½ N) and ½ Marchigiana + ½ Nellore (½ M + ½ N)), were raised on pastures, finished in dry lot and slaughtered at live weights ranging from 445 to 517 kg, and at ages ranging from 679 to 863 days. During the dry lot period, which lasted 114 days, animals were fed sorghum silage offered ad libitum, and a concentrate (13.5 MJ of ME, 18% CP in the DM) at 1% live weight per day. Genetic group influenced hot carcass weight, forequarter weight, meat weight in the spare ribs, as well as meat and bone weights in the forequarter. Animals in the ½ M + ½ N group were superior both to those in the Nellore and in the ½ G + ½ N groups for hot carcass weight, forequarter weight and meat weight in the spare ribs. The ½ M + ½ N group also differed from the ½ R + ½ N and from the ½ G + ½ N groups in terms of forequarter weight and meat weight in the forequarter, respectively. Conversely, forequarter bone weight of ½ M + ½ N animals was higher than in animals from the Nellore and the ½ R + ½ N groups, respectively. There was no effect of genetic group on hindquarter cuts, except for higher shank and knuckle weights in the ½ M + ½ N group compared to the ½ G + ½ N and Nellore groups, respectively.

Growth performance, carcass quality, and noncarcass components of indigenous Caribbean goats under varying nutritional densities1

Studies were conducted to determine the effects of feeding regimens on growth and carcass quality of the Creole goat, a genotype indigenous to the Caribbean. Forty kids weighing 9.0 +/- 1.2 kg of BW were reared indoors after weaning. Four supplement amounts were compared (10 kids per treatment): the G0 group received the basal diet (tropical forage, 8.8 MJ of ME and 108 g of CP/kg of DM) without concentrate, whereas the G100, G200, and G300 groups were offered 130, 230, and 310 g/d of concentrate (13.6 MJ of ME and 209 g of CP/kg of DM), respectively, in addition to the basal diet. The kids were slaughtered according to the standard procedure at 22 to 24 kg of BW for assessment of carcass traits and meat quality. Total DMI increased significantly, from 51 to 78 g/kg of BW(0.75), for G0 to G300 kids, whereas their ADG doubled from 42 to 84 g/d (P < 0.01; P < 0.01, respectively). The G:F values reached 125 to 130 for the G200 and G300 diets and were satisfactory compared with literature values. The carcass weight and dressing percentage (P < 0.01) increased from group G0 to G300, from 9 to 13 kg and from 42 to 51%, respectively. The proportions of the different cuts (related to the carcass weight) did not vary by diet. The conformation score increased significantly (P < 0.05) among the 4 groups from an average score of 3.2 to 4.0 (score/5). There was a significant effect (P < 0.01) of supplement amount on the accumulation of internal fat tissues: the kidney fat weight increased from 113 to 253 g from the G0 to the G300 group. Regardless of the feeding level and amount of internal fat, the carcasses had an acceptable fat cover score, which remained less than 2.6 (score/5). A significant effect was not observed for the ultimate pH and the main color variables of the meat. The cooking loss and the shoulder DM content varied (P < 0.05) with the supplement amount. By increasing the nutritional density of the diet, it was possible to obtain well-conformed and heavy carcasses, with no excessive fattening. Indigenous Creole goats have potential as meat animals when fed to gain more than 80 g/d. The optimal supplement supply with good-quality grass would be approximately 3.69 MJ of ME/d in our conditions. Further studies are required on meat sensory parameters and fatty acid profiles.

Influência da temperatura ambiente, do nível de energia da dieta e do sexo sobre características de desempenho e de carcaça de suínos

Suínos são sensíveis a altas temperaturas e os mecanismos de termorregulação representam custos energéticos direcionados à perda de calor corporal, reduzindo o bem-estar e o desempenho produtivo, e alterando a qualidade de carcaça. O objetivo deste estudo foi avaliar os efeitos do sexo e do nível energético da dieta em suínos em crescimento-terminação submetidos às variações sazonais de temperatura características de clima subtropical úmido e propor um modelo matemático que prediga o desempenho dos animais e características de carcaça. Vinte e oito leitões mestiços foram distribuídos aleatoriamente a 12 tratamentos em arranjo fatorial 2x2x3 (2 sexos, 2 condições ambientais e 3 níveis de energia na dieta). A condição de estresse calórico (câmara climática) apresentou temperaturas de 31 ºC às 7:00 e 22 ºC às 17:00 (com máxima de 33 ºC) e a condição de conforto térmico (galpão) apresentou temperaturas de 18 ºC às 7:00 e 24 ºC às 17:00 (com máxima de 27 ºC). Os animais foram alimentados ad libitum com dietas contendo 12,2 (baixo), 13,6 (médio) e 15,0 (alto) MJ EM/kg MS. O consumo voluntário de ração, ganho de peso diário e peso corporal final foram maiores (P&lt;0,01) na condição de conforto térmico e sofreram influências do sexo (P&lt;0,01) para os suínos em crescimento. A conversão alimentar decresceu conforme aumentou a energia da dieta (P&lt;0,01), com valores de 2,67, 2,59 e 2,32 (para 12,2, 13,6 e 15,0 MJ EM / kg MS, respectivamente). Houve interação entre nível dietético de energia e sexo somente para ganho diário de peso. Para os suínos em terminação, também se observou efeito da condição ambiental (P&lt;0,01) sobre o consumo voluntário de ração, ganho diário de peso e peso corporal final, com o desempenho dos animais sendo melhor na condição de conforto térmico. Os valores de conversão alimentar foram 3,55:1, 3,42:1 e 2,95:1 para níveis de energia baixo, médio e alto, respectivamente. Foram observadas interações entre nível de energia e sexo para as variáveis consumo de ração, ganho diário de peso e peso final (P&lt;0,05). O rendimento e qualidade de carcaça foram afetados pelas condições ambientais e nível dietético de energia. Tanto o peso da carcaça quente, como da carcaça resfriada aumentaram com o aumento da energia na dieta. Após o resfriamento, o peso da carcaça aumentou em 1,142 kg/MJ EM, enquanto a espessura de toucinho esteve acima de 252 mm/MJ EM. A espessura do músculo longissimus thoracis foi 16 mm menor nos animais em estresse calórico, mas o conteúdo de carne magra foi 2,68% maior nestes animais. Equações de regressão para predição de valores de desempenho nas diversas situações estudadas foram propostas.

Effects of Dietary Selenium Source and Storage on Internal Quality of Eggs

A 4-week experiment was carried out on 360 laying hens of the Hy Line Brown hybrid. Laying hens were divided into three groups (C, E1 and E2) with 120 hens in each group and kept in 24 cages. Hens were fed layer diets containing 18% of crude protein and 11.60 MJ ME. Hens in the control group C were fed diets that contained 0.2 mg/kg of inorganic selenium (sodium selenite). Experimental groups E1 and E2 were given diets with increased concentrations of selenium as follows: E1 = 0.4 mg/kg of selenium (sodium selenite), E2 = 0.4 mg/kg of organic selenium (Sel-Plex). Selenium concentration in diets affected significantly the content of selenium in albumen (P &lt; 0.001) and yolk (P &lt; 0.05). The highest concentration of selenium was determined in albumen and yolk of eggs produced in group E2 (345 ng/g and 783 ng/g, respectively), then in eggs of group E1 (230 ng/g and 757 ng/g, respectively), and group C had the lowest concentration of selenium in albumen and yolk (181 ng/g and 573 ng/g, respectively). After 28 days of storage at 4 °C, the eggs containing organic selenium had more freshness (VN: C = 32.9, E1 = 2.60, E2 = 2.11). It was concluded that higher concentration of organic selenium in eggs was a limiting factor in metabolic processes, which positively affected the indicators of egg freshness.

Influence of sunflower meal based diets supplemented with exogenous enzyme and digestible lysine on performance, digestibility and carcass response of broiler chickens

Response of broiler chickens to 2 levels of endo-1,4-β xylanase (EC 3.2.1.8) and endo-1,3-β glucanase (EC 3.2.1.6) cocktail (with and without), 3 levels of digestible lysine (8.0, 9.0 and 10.0 g kg −1 with the applicability of ideal protein concept), and 2 levels of sunflower meal (SFM; 200 and 300 g kg −1) were evaluated in the present experiment. The factorial design of 2 × 3 × 2 using 2448 one-day-old straight-run Hubbard broiler chicks was used to evaluate the effect of two levels of enzymes, 3 levels of digestible lysine and 2 levels of SFM in practical vegetable based mash diets having 11.51 MJ ME and 190 g CP kg −1 from 1 to 42 d of age. The BW gain was improved linearly (P≤0.001) with the increasing level of digestible lysine during 1–21 d and 22–42 d of age. The gain:feed was improved linearly (P≤0.001) with the increasing digestible lysine during 1–21 d and a quadratic effect of digestible lysine was noted during 1–42 d where 9.0 and 10.0 g digestible lysine kg −1 of diet responded similar for gain:feed. Enzyme supplementation at 300 g SFM kg −1 improved BW gain (P≤0.008) and gain:feed (P≤0.048) during 1–21 d. When 10.0 g digestible lysine kg −1 of diet was used at 2 levels of SFM, gain:feed was improved (P≤0.013) during 1–21 d. However, this interaction was not significant on other performance parameters either at 21 d or at 42 d of age. The enzyme supplementation decreased the feed intake (P≤0.019) by 4.67% and improved gain:feed by 5.53% (P≤0.012) during 1–42 d without affecting BW gain. The main effect of SFM was not significant for live performance or carcass response at any stage. The depression in breast weights at 42 d due to 300 g SFM or 8.0 g digestible lysine kg −1 of diet was compensated by the enzyme addition (a significant enzyme × SFM effect). No significant effect of enzyme, SFM, digestible lysine or their interactions was observed on apparent metabolizable energy of the diets. Coefficient of total tract apparent digestibility of nitrogen was improved by the addition of enzyme to 10.0 g digestible lysine kg −1 of diet or addition of digestible lysine to high SFM. The results of the present study revealed a positive response of enzyme addition in low nutrient density and high SFM diets. Moreover, digestible lysine is not suggested to be lowered than 10.0 g during 1–21 d and it may be reduced to 9.0 g kg −1 if a single diet having high level of SFM is planned to be offered during 1–42 d.

Variation in Plasma Concentrations of Insulin-Like Growth Factor-I in Pasture-Fed Holstein Cows

The objective of this 5-wk study was to determine dietary effects on plasma concentrations of insulin-like growth factor-I (IGF-I), as well as milk production and milk components in pasture-fed dairy cows. Thirty-two Holstein cows 4 to 5wk postpartum were randomly assigned to 4 dietary subgroups. Feed was provided twice daily ad libitum at 0900 and 1600h composed of fresh-cut pasture, meadow hay, and pelleted cereal grain to achieve differing levels of DMI and ME density (LL: 16.6kg of DMI and 174 MJ of ME; HL: 17.3kg of DMI and 181.1 MJ of ME; LH: 15.4kg of DMI and 183.1 MJ of ME; HH: 17.9kg of DMI and 213.3 MJ of ME, with the first letter indicating DMI and the second ME, and with H indicating high and L indicating low, respectively). The first day cows were placed on their diets was designated d 0. Concentrations of IGF-I were measured in frozen-thawed samples of plasma using a verified ELISA. Dietary treatment had affected plasma concentrations of IGF-I by d 7 with cows on high ME diets having greater IGF-I concentrations at d 14 (83.7 vs. 45.6ng/mL) than cows on the low ME diets. The level of DMI had less effect on plasma concentrations of IGF-I at d 14 (72.2 vs. 57.1ng/mL). Dietary treatment effects on these concentrations had stabilized by d 21. Day-to-day variation in mean plasma concentrations of IGF-I within each dietary treatment was low during an intensive period of daily sampling for 14 d (from d 22 to 35). Within-cow day-to-day variation was also low compared with that among cows within the same dietary group and was associated with a high repeatability in the day-to-day concentration of IGF-I in individual cows. Intraclass correlation coefficients for IGF-I ranged from 0.56 (± 0.14) to 0.88 (± 0.06) with a combined (pooled) value for the 4 subgroups of 0.77 (± 0.05). The ME and DMI effects (H vs. L) at d 35 were 79.3 vs. 41.4 and 62.0 vs. 55.7ng/mL, respectively. Although the ME and DMI differences also affected milk yield and compositional parameters, the effects were not as proportionately great as those measured for IGF-I. Altering the ME or DMI components of the pasture-based diets produced changes in plasma IGF-I concentrations that did not become stabilized for 3wk, but were then highly repeatable for individual cows within each dietary group. Both observations have relevance to interpreting data related to plasma concentrations of IGF-I in lactating Holstein cows.

Effect of intrauterine growth restriction on weight and cellularity of gastrointestinal tract in postnatal lambs

This study investigated the effect of intrauterine growth restriction (IUGR) during late pregnancy on weight and cellularity of the gastrointestinal tract (GIT) in postnatal lambs. Twenty-three Mongolian lambs were entered into the study. Their dams were mated at a synchronized estrus and divided into three groups offered 0.175 MJ ME kg-0.75 d-1 (Restricted Group 1, RG1), 0.33 MJ ME kg-0.75 d-1 (Restricted Group 2, RG2) and Control Group (CG, ad libitum access to feed) during their late pregnancy (90 d), respectively. The lambs were slaughtered at birth (neonatal lambs) and at 28 wk of age. The neonatal abomasum weight, jejunum weight and length, abomasum and jejunum DNA content, and the reticulum protein:DNA ratio were lower for RG1 than those of CG (P &lt; 0.05). At 28 wk of age, there were no significant difference in the weights and lengths of jejunum and the weight of abomasum in the lambs among RG1, RG2 and CG (P &gt; 0.05). However, the rumen and omasum weight, and omasum DNA content were lower for RG1 than for CG (P &lt; 0.05). For the jejunum, the protein:DNA ratios in RG2 were significantly higher than those of CG (P &lt; 0.05). These changes in the weight and cellularity of the GIT may have significant implications on postnatal growth and health. Key words: Intrauterine growth restriction, postnatal lambs, gastrointestinal tract, weight, cellularity

The response of Japanese quails (heavy body weight line) to dietary energy levels and graded essential amino acid levels on growth performance and immuno-competence

The response of growing quails ( n = 900, divided into 36 subgroups) to dietary levels of essential amino acids (EAA) at different energy levels on growth and immunity was investigated. Nine diets including three levels of metabolizable energy (ME, 11.30, 12.13 and 12.97 MJ ME kg − 1 ) each at three levels of EAA (low, medium and high) in a 3 × 3 factorial design were formulated. Each diet was offered to 4 replicated groups up to 5 weeks of age. The ratio of lysine to protein and the level of methionine and threonine to lysine remained almost similar in all the diets as specified by NRC [NRC, 1994. Pages 44–45 in Nutrients requirements of poultry. 8th ed. Natl. Acad. Press, Washington, DC.]. Body weight gain, feed intake and feed conversion ratio did not differ statistically due to the treatments i.e. interaction of ME and EAA levels. However, there was linear increase in body weight gain with increased EAA levels during 0–3 or 0–5 weeks of age. Feed intake increased linearly with the decreased ME ( P < <0.01) and increased EAA ( P < 0.01) in diets. Feed conversion ratio (FCR) improved ( P < 0.01) linearly with increase in dietary ME concentration from 0–3 or 0–5 weeks of age. FCR and energy efficiency improved in diets with medium and high levels of EAA during 0–3 weeks, while it did not differ during 0–5 weeks of age. Protein efficiency (PE) improved linearly ( P < 0.01) with decreased EAA levels during 0–3 or 0–5 weeks of age, and also with the increase in dietary ME level during 0–5 weeks growth phase. Nitrogen retention per unit energy intake was significantly higher in diet containing 12.97 MJ ME kg − 1 with high level of EAA. Humoral (SRBC) and cellular (PHA-P) immune response and yield of immune organs did not differ due to ME, EAA or ME x EAA. Therefore, it can be concluded that the optimum level of dietary ME is 11.30 MJ kg − 1 with CP 25.83%, lysine 1.49%, methionine 0.58% and threonine 1.17% on dry matter basis during 0–5 weeks of age for gain. However for optimum feed conversion, the growing quails require diet with ME 12.97 MJ kg − 1 with CP 23.23%, lysine 1.30%, methionine 0.50% and threonine 1.02% for 0–5 weeks of age.