High Plane Of Nutrition Research Articles

Effects of the plane of nutrition during the latter grower and entire finisher phases on grow-finish pig performance in summer.

The present study was undertaken to investigate the effects of the plane of nutrition (PN) for growing-finishing pigs on growth performance and meat quality in summer. One hundred and two barrows and 102 gilts weighing approximately 44 kg were placed on a high-, medium-, or low-plane grower diet (HPG, MPG, or LPG) with ME and lysine concentrations ranging from 3.33 to 3.40 Mcal/kg and 0.93% to 1.15%, respectively, for 29 days in 6 replicates (pens) in total. Pigs from each grower pen were divided into two finisher pens and provided with a high-plane finisher diet (HPF) containing 3.40 Mcal ME and 9.5 g lysine/kg and a low-plane finisher diet (LPF; 3.25 Mcal ME and 8 g lysine/kg), respectively, up to approximately 110 kg, and slaughtered. Growth performance of the pigs, including average daily gain (ADG), average daily feed intake (ADFI), and gain:feed ratio, was not influenced by the grower-phase PN during any of the grower phase, a 31-d finisher phase I, and ensuing phase II. However, both the ADG and gain:feed ratio were greater (p < 0.05) for the HPF group than for the LPF group during the finisher phase I (748 vs. 653 g with SEM = 13 g and 0.333 vs. 0.299 with SEM = 0.008, respectively). The ADG, but not gain:feed ratio, was greater for the HPF group vs. LPF during the finisher phase II (673 vs. 623 g with SEM = 15 g for ADG and 0.322 vs. 0.323 with SEM = 0.005 for the gain:feed ratio). The carcass backfat thickness (BFT) was greater for the LPF group vs. HPF within the pigs which had been placed on LPG during the grower phase, but not within the pigs from the HPG or MPG group. Physicochemical characteristics of the longissimus dorsi muscle (LM) and sensory quality attributes of fresh and cooked LM were not influenced by either the grower-phase or finisher-phase PN. In conclusion, high PN is necessary for finishing pigs during the hot season to minimize the reduced rate of weight gain and also to prevent the increase of BFT that could result from low PN.

Effects of the plane of nutrition for grower pigs on their grow-finish performance and meat quality in winter.

Little is known about the effects of the plane of nutrition on growth performance and meat quality of grow-finish pigs under commercial production conditions. The present study was thus addressed to this virtually unanswered question. One hundred and two barrows and 102 gilts weighing approximately 24 kg were fed phase I and II grower diets with a high, medium, or low plane of nutrition (HP, MP, or LP) to approximately 43 and 70 kg, respectively, in 6 replicates (pens). Subsequently, the HP and MP groups were fed the HP and MP1 finisher diets, respectively, the LP group being fed a second MP (MP2) finisher diet (LP1 group). Moreover, 68 LP-grower-fed barrows and gilts were added to the feeding trial and fed the MP1 and LP finisher diets to approximately 95 kg and thereafter, respectively (LP2 group). All MP diets had the lysine:calorie ratios comparable to the RNC recommendations, with < 18% differences between those of the HP and LP diets. The finisher pigs were reared in 16 pens and slaughtered at approximately 115 kg. The gain:feed ratio, but not average daily gain (ADG), was greater for the HP group than for the MP and LP during the grower phase I whereas during the grower phase II, ADG was greater (p < 0.05) for the HP and LP groups vs. MP. During the finisher phase I, ADG was less for the LP (LP1 + LP2) group vs. HP and MP, with no difference between the HP and MP groups; the gain:feed ratio was less for the LP vs. MP group. Backfat thickness was greater for the LP vs. HP group. The water holding capacity of fresh longissimus dorsi muscle (LM) and the sensory juiciness score for cooked LM were greatest for the LP group, the sensory flavor and tenderness scores being greater for the LP group vs. MP. In conclusion, results suggest that compensatory growth occurred for the LP and MP groups during the grower phase II and finisher phase I, respectively, with fat deposition increased for the LP group and that meat quality could be improved by the use of LP.

Effect of dietary n-3 polyunsaturated fatty acid supplementation and post-insemination plane of nutrition on systemic concentrations of metabolic analytes, progesterone, hepatic gene expression and embryo development and survival in beef heifers

Nutrition, and particularly dietary energy intake, plays a fundamental role in reproductive function in cattle. There is some evidence that supplemental omega-3 dietary polyunsaturated fatty acids (n-3 PUFA) can exert positive effects on fertility. The objectives of this study were to evaluate the effect of dietary n-3 PUFA supplementation, post-insemination energy plane of nutrition and their interaction on embryo survival in cattle. Crossbred beef heifers (n = 185) were individually offered barley straw ad libitum and 6 kg DM of concentrate supplemented with either a rumen-protected source of saturated fatty acid (palmitic; control, CON) or a partially rumen-protected n-3 PUFA-enriched supplement (n-3 PUFA). Estrous was synchronised using two injections of PG administered at 11-d intervals and following artificial insemination (AI = Day 0) 179 heifers exhibiting oestrus were inseminated and assigned to one of two dietary treatments: (i) remain on their pre-insemination high dietary plane of nutrition (High) or (ii) restricted to 0.6 × estimated maintenance energy requirements (Low) in a 2 × 2 factorial design. The heifers were then maintained on their assigned diets until slaughter and embryo recovery on Day 16 (n = 92) or pregnancy diagnosis by ultrasound scanning at Day 30 post-AI (n = 87). Plasma concentrations of fatty acids, metabolites, insulin, progesterone (P4) and insulin-like growth factor 1 (IGF-1) were measured at appropriate intervals. Hepatic expression of mRNA for aldo-keto reductase (AKR1C), cytochrome P450 2C (CYP 2C) and cytochrome P450 3A (CYP 3A) was examined. The n-3 PUFA supplementation increased plasma n-3 PUFA concentration (P < 0.05) and reduced n-6: n-3 PUFA ratio (P < 0.05). Plasma IGF-1 was higher for n-3 PUFA relative to the CON (P < 0.05) and for High compared with Low plane of nutrition post-AI (P < 0.05) groups. A low plane of nutrition post-AI increased plasma concentrations of progesterone from Days 7–16 after insemination (P < 0.001) but reduced embryo length (P < 0.001). Supplementation with n-3 PUFA reduced and tended to reduce hepatic expression of CYP2C (P = 0.01) and CYP3A (P = 0.08), respectively. However, while dietary n-3 PUFA supplementation and an abrupt reduction in nutrient status following insemination elevated plasma concentrations of n-3 PUFA and mid and late phase P4, respectively, there was no effect of either PUFA supplementation or post-insemination plane of nutrition on embryo survival.

Effect of Early Calf-Hood Nutrition on the Transcriptional Regulation of the Hypothalamic-Pituitary-Testicular axis in Holstein-Friesian Bull Calves

The aim of this study was to investigate the effect of early calf-hood nutrition on the transcriptomic profile of the arcuate nucleus of the hypothalamus, anterior pituitary and testes in Holstein-Friesian bulls. Holstein-Friesian bull calves with a mean (±S.D.) age and bodyweight of 19 (±8.2) days and 47.5 (±5.3) kg, respectively, were offered a high (n = 10) or low (n = 10) plane of nutrition in order to achieve an overall growth rate of 1.2 and 0.5 kg/day. At 126 (±3) days of age, calves were euthanized, hypothalamus (arcuate region), anterior pituitary and testicular parenchyma samples were harvested and RNAseq analysis was performed. There were 0, 49 and 1,346 genes differentially expressed in the arcuate nucleus, anterior pituitary and testicular tissue of bull calves on the low relative to the high plane of nutrition, respectively (P < 0.05; False Discovery Rate <0.05). Cell cycle processes in the anterior pituitary were down regulated in the low relative to the high plane of nutrition; there was no differential expression of genes related to reproductive processes. Gene expression involved in cholesterol and androgen biosynthesis in the testes were down regulated in animals on the low plane of nutrition. This study provides insight into the effect of early life plane of nutrition on the regulation of the HPT axis.

Short communication: The effects of offering a high or low plane of milk preweaning on insulin-like growth factor and insulin-like growth factor binding proteins in dairy heifer calves

Although positive effects on growth have been shown when calves are placed on high planes of nutrition, little information exists regarding the effect of this feeding strategy on insulin-like growth factor-1 (IGF-1), a hormone whose fundamental action is to stimulate growth, and its binding proteins during the preweaning period. The objective of this study was to characterize IGF-1 and insulin-like growth factor binding protein (IGFBP) concentrations in plasma during the pre- and immediate postweaning period, when calves were offered a high or low plane of whole milk. Twenty-six female Holstein calves were randomly assigned to either a high (HI; 10 L/d; n = 13) or low (LO; 5 L/d; n = 13) plane of milk following colostrum feeding at d 3 of life. Calves were fed their respective diet as whole milk until d 48 when a 10-d weaning transition began. During this transition, milk was reduced by 10% per day such that all calves received no milk on d 59 of life. Blood samples were collected bi-weekly to measure IGF-1 and IGFBP in plasma. Calves fed HI gained more body weight than calves fed LO during the preweaning period (d 1-48 of life; 0.90 vs. 0.65 kg/d); however, no differences in average daily gain or metabolizable energy intake during the weaning transition (d 48-58 of life) or postweaning period (d 59-70 of life) occurred. Concentrations of IGF-1 were higher in HI calves during the preweaning period, which was associated with high levels of IGFBP-3 at wk 5 and lower IGFBP-2 during each measured time point preweaning as compared with LO. Insulin-like growth factor binding protein-4 was lower in HI calves only during wk 1, and IGFBP-5 was not affected by the dietary treatment. Overall, offering a high plane of nutrition was associated with changes in plasma IGF-1 and IGFBP that would indicate greater growth and development preweaning but not necessarily postweaning.

Relationships of nutritional plane and feed efficiency with sexual development and fertility related measures in young beef bulls

Sexual development in beef bulls appears to be influenced by nutritional plane and feed efficiency. Yearling bulls fed high (GRAIN = 49) and moderate (ROUGHAGE = 109) nutritional planes, were submitted to a performance test where scrotal circumference (SC), scrotum and testis ultrasonograms and hormones were monitored throughout. Scrotal thermographs, blood cell counts and semen were evaluated at the end of the test. Residual feed intake (RFI) was the measure of feed efficiency, and bulls within each population were characterized as efficient and inefficient. During the test period, the GRAIN group had greater triiodothyronine (T3), leptin and scrotal skin thickness (SST) while having greater T3, leptin, % motile sperm, % normal sperm, scrotal temperature and values for red blood cell variables at the end of the test when compared to the ROUGHAGE group. During the test, the efficient GRAIN group had lesser testis pixel intensity while at the end of the performance test the bulls of this group had greater % normal sperm and lower testis pixel intensity compared to bulls in inefficient GRAIN group. In comparison, the efficient ROUGHAGE group had less T3, SC and SST while at the end of the test these bulls had less T3, leptin, SC, SST and scrotal temperature compared to bulls in the inefficient ROUGHAGE group. Complete blood cell variables, semen quality, scrotal biometry and thermography explained most of the variation in RFI. Results of the present study support the hypothesis that there is an antagonistic relationship between feed efficiency and sexual development in young bulls, which seems partially offset when there is a greater plane of nutrition. Thus, feed efficiency should be factored in the reproductive evaluation of sires.

Effect of early calf-hood nutrition on the transcriptomic profile of subcutaneous adipose tissue in Holstein-Friesian bulls

BackgroundAdipose tissue is a major endocrine organ and is thought to play a central role in the metabolic control of reproductive function in cattle. Plane of nutrition during early life has been shown to influence the timing of puberty in both male and female cattle, though the exact biological mechanisms involved are currently unknown. The aim of this study was to investigate the effect of early calf-hood nutrition on the transcriptomic profile of subcutaneous adipose tissue in Holstein-Friesian bulls to identify possible downstream effects on reproductive physiology.ResultsHolstein-Friesian bull calves with a mean (±S.D.) age and bodyweight of 19 (±8.2) days and 47.5 (±5.3) kg, respectively, were assigned to either a high (n = 10) or low (n = 10) plane of nutrition. Calves were fed in order to achieve an overall growth rate of 1.08 and 0.57 kg/day for the high and low plane of nutrition treatments, respectively. At 126 days of age, the bulls were euthanized, subcutaneous adipose tissue samples were harvested and RNAseq analysis was performed. There were 674 genes differentially expressed in adipose tissue of calves on the low compared with the high plane of nutrition (P < 0.05; FDR < 0.05; fold change > 2.0). High plane of nutrition positively altered the expression of genes across an array of putative biological processes but the most dominant cellular processes affected were cellular energy production and branched chain amino acid degradation. A high plane of nutrition caused upregulation of genes such as leptin (LEP) and adiponectin (ADIPOQ), which are known to directly affect reproductive function.ConclusionsThese results provide an insight into the effect of augmenting the plane of nutrition of Holstein-Friesian bull calves in the prepubertal period on the transcriptome of adipose tissue.

Ovine placental steroid synthesis and metabolism in late gestation.

Steroid synthesis is required for pregnancy maintenance and for parturition, but comparatively little is known about the major metabolic routes that influence circulating concentrations. Dietary intake changes progesterone and estradiol concentrations in pregnant ewes but whether this reflects placental synthesis is unknown. Progesterone metabolism by 5alpha-reduction is a major metabolic route in other species and can influence the onset of parturition. Therefore, studies were conducted to (1) determine placental enzyme activity, progesterone, and estradiol measured by immunoassay in late gestation ewes on low-, moderate-, and high-nutritional planes, (2) to assess the significance of 5alpha-reduction of progesterone in determining progesterone concentrations in late gestation ewes (gestation day 145) given finasteride to inhibit 5alpha-reductase metabolism. In the second experiment, steroid profiles were examined comprehensively in blood and tissues by liquid chromatography tandem mass spectrometry for the first time in this species. Dietary intake altered progesterone and estradiol serum concentrations but without correlated changes in placental 3beta-hydroxysteroid dehydrogenase, 17alpha-hydroxylase/17,20-lyase cytochrome P450 or aromatase activity. 5alpha-reduced pregnane metabolites were identified in ewes at 145 days of gestation, but concentrations were lower than those of progesterone. Finasteride inhibited 5alpha-reduced progesterone metabolism but did not impact serum progesterone concentrations in these ewes. We conclude that (1) diet-induced changes in serum progesterone and estradiol concentrations are not likely a result of altered placental synthesis of sex steroid but most likely by their metabolism, and (2) metabolism by 5α-reduction is not a major determinant of systemic progesterone concentrations in late gestation ewes.

Plane of nutrition before and after 6 months of age in Holstein-Friesian bulls: I. Effects on performance, body composition, age at puberty, and postpubertal semen production

The aim of this study was to examine the effect of plane of nutrition (1) during the first 6 mo of life and (2) from 6 mo of age to puberty on early growth characteristics, age at puberty, and postpubertal semen production in Holstein-Friesian bulls. Holstein-Friesian bull calves (n = 83) with a mean (standard deviation) age and body weight of 17 (4.4) d and 52 (6.2) kg, respectively, were assigned to a high (Hi) or low (Lo) plane of nutrition for the first 6 mo of life. The Hi and Lo calves received 1,200 and 450 g of milk replacer, respectively; Hi calves were fed concentrate ad libitum and Lo were fed a maximum of 1 kg concentrate daily, and concentrate allowances remained the same after weaning. At 24 wk of age, bulls were reassigned within treatment to either remain on the same diet or to switch to the opposite diet until puberty, resulting in 4 treatment groups: Hi-Hi, Hi-Lo, Lo-Lo, and Lo-Hi. After puberty, all bulls were fed a moderate plane of nutrition until 60 wk of age; thereafter, the diet was ad libitum concentrates until slaughter at 72 wk of age. Bulls were weighed weekly before weaning and every 2 wk after weaning. Scrotal circumference (SC) was measured every 2 wk, beginning at 15 wk of age. Beginning at a SC of 24 cm, electro-ejaculation was carried out every 2 wk to establish the onset of puberty. Semen collection continued monthly after puberty. Thermal images of the scrotum were taken monthly from 28 to 36 wk of age. Scrotal skin thickness (SST) was measured monthly (from 16 wk of age to puberty) using a digital calipers. Bulls on the Hi diet had a higher scrotal temperature and SST at each time point than those on the Lo diet. Average daily gain (ADG) was greatest in Hi-Hi bulls, with Hi-Lo and Lo-Hi having similar ADG but both being greater than Lo-Lo. Bulls on the Hi diet pre-6 mo of age were younger at puberty, regardless of diet offered post-6 mo of age. Bulls offered a Hi diet post-6 mo were heavier at puberty. Neither scrotal temperature nor dietary treatment affected postpubertal semen production variables. In conclusion, a high plane of nutrition during the first 6 mo of age hastened the onset of puberty and the availability of saleable semen, regardless of plane of nutrition post-6 mo of age.

Plane of nutrition before and after 6 months of age in Holstein-Friesian bulls: II. Effects on metabolic and reproductive endocrinology and identification of physiological markers of puberty and sexual maturation

The aim of this study was (1) to examine the effect of plane of nutrition during the first and second 6 mo of life on systemic concentrations of reproductive hormones and metabolites in Holstein-Friesian dairy bulls, and (2) to establish relationships with age at puberty and postpubertal semen production potential. Holstein-Friesian bull calves (n = 83) with a mean (standard deviation) age and body weight of 17 (4.4) d and 52 (6.2) kg, respectively, were assigned to a high or low plane of nutrition for the first 6 mo of life. At 24 wk of age, bulls were reassigned, within treatment, either to remain on the same diet or to switch to the opposite diet until puberty, resulting in 4 treatment groups: high-high, high-low, low-low, and low-high. Monthly blood samples were analyzed for metabolites (albumin, urea, total protein, β-hydroxybutyrate, glucose, nonesterified fatty acid, triglycerides and creatinine), insulin, insulin-like growth factor-1, leptin, adiponectin, FSH, and testosterone. A GnRH challenge was carried out at 16 and 32 wk of age (n = 9 bulls per treatment). Blood was collected at 15-min intervals for 165 min, with GnRH administered (0.05 mg/kg of body weight, i.v.) immediately after the third blood sample. Blood samples were subsequently analyzed for LH, FSH, and testosterone. Stepwise regression was used to detect growth and blood measurements to identify putative predictors of age at puberty and subsequent semen quality traits. Metabolic hormones and metabolites, in general, reflected metabolic status of bulls. Although FSH was unaffected by diet, it decreased with age both in monthly samples and following GnRH administration. Testosterone was greater in bulls on the high diet before and after 6 mo of age. Testosterone concentrations increased dramatically after 6 mo of age. Luteinizing hormone was unaffected by diet following GnRH administration but basal serum LH was greater in bulls on a high diet before 6 mo of age. In conclusion, the plane of nutrition offered before 6 mo of age influenced metabolic profiles, which are important for promoting GnRH pulsatility, in young bulls.

Effect of dietary manipulation and vaccination of turkey breeder hens on immunoglobulin levels of yolk, yolk sac and neonate poults.

Two hundred turkey breeder hens and 24 viable toms of 30-35weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8-week duration. After 6weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R2 B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p<.05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p<.05) than that of the control groups. In addition, HI titre values were significantly higher (p<.05) in the day-old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p<.01) positive correlation between serum IgG and IgM of the breeder birds and day-old chicks. Similarly, there was significantly (p<.05) positive correlation between yolk IgG and IgM after 1-month experimental feeding and yolk sac IgG and IgM. Positive correlation (p<.05) also existed between yolk sac IgM and day-old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14days post-vaccination were positively correlated with their egg yolk after 10 and 15days post-vaccination, yolk sac and day-old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac.

Plane of nutrition during the rearing phase for replacement ewes of four genotypes: II - effects on performance during first pregnancy and to weaning, and of their progeny

Plane of nutrition (PN) offered to ewe replacements during the rearing phase (8 to 17 months) and first pregnancy may affect reproductive and progeny performance when replacements are joined at ~19 months. The effects of PN offered to spring-born ewe replacements during their first winter (winter_1), second summer (summer_2) and subsequent winter (mid and late pregnancy; winter_2) were evaluated, over 3 consecutive years, using 287 ewe lambs of four genotypes: Charmoise×Scottish Blackface (C×SBF), Belclare×SBF (Bel×SBF), Belclare (Bel) and Belclare×SBF (heterozygous for a gene, either FecGH or FecXG mutations, that increases ovulation rate: BelMG×SBF). Ewe lambs were offered, daily, a deferred-grazed herbage allowance (HA) of either 0.75 or 1.75 kg dry matter during winter_1. During summer_2 the replacements were set-stocked to maintain sward heights of 4 or 6 cm. Ewes were housed during mid and late pregnancy (winter_2) and offered either medium or high-feed-value grass silage, thus yielding a 2×2×2 factorial design. Increasing HA during winter_1 and residual sward height during summer_2 increased ewe BW post joining (P<0.001) and at lambing (P<0.01), but had no effect (P>0.05) on number of lambs reared. Increasing HA during winter_1 increased lamb BW at birth (P<0.05) and reduced carcass fat score (P<0.05). There was a significant interaction between PN offered during winter_1 and summer_2 for average daily gain (ADG) from birth to 5 weeks (P<0.01) and from 5 to 10 weeks (P<0.05): progeny of replacements that experienced either a high or low PN throughout the rearing phase had lower ADG than lambs born to the replacements that experienced a low PN only during winter_1 or summer_2. Increasing PN during winter_2 increased ewe BW (P<0.001), lamb BW at birth (P<0.001) and weaning (P<0.05) and reduced the proportion of ewes that failed to lamb (P<0.01). Ewe genotype had a significant (P<0.001) effect on litter size (1.48 to 2.45), number of lambs reared, lamb BW at birth and weaning, lamb ADG and age at slaughter. It is concluded that, among the nutrition treatments examined, increasing PN during mid and late pregnancy had the greatest effect on ewe and progeny performance. Although increasing PN offered during winter_1 increased lamb birth BW, PN offered during summer_2 had no effect on lamb performance. There were no significant interactions between PN and ewe genotype.

Effect of Feeding Milk Replacer Alone or in Combination with Probiotic on Pre-weaning Performance, Nutrient Utilization and Rumen Fermentation in Malpura Lambs

To assess influence of feeding milk replacer alone and with probiotic (Lactobacillus acidophillus) supplementation on pre-weaning growth performance and nutrient utilization, 48 Malpura lambs of 7d of age were distributed randomly into three equal groups. Lambs were maintained individually under feeding regimens of ad libitum creep mixture along with green and dry roughage (C-0; Control), and the same supplemented with milk replacer alone (C-MR), or milk replacer in combination with live probiotic culture (C-MRP). Lambs were allowed to suckle their respective dams in the morning and evening till 91d of age, and fed ad libitum green leaves of Prosopis cinereria and dry cowpea hay. Pre-weaning performance of lambs in terms of weaning weight (20.7 kg, P=0.009), average daily gain (ADG; 183.1g, P=0.003) and feed conversion ratio was higher (P=0.019) in C-MRP lambs as compared to control (C0). The DM intake was significantly (P=0.026) higher in C-MR and C-MRP lambs due to higher plane of nutrition. Rumen pH was lowest (P=0.023) in C-MR lambs. Ammonia concentration decreased and total VFAs increased with milk replacer feeding in both C-MR and C-MRP groups. Level of propionic acid increased and acetic acid decreased in C-MR and C-MRP lambs. Rumen ciliate protozoa population (x104/ml) decreased (P=0.022) in C-MR (91.3) and C-MRP (95.4) group lambs than in C-0 lambs (122.8). Milk replacer feeding in C-MR and C-MRP lamb improved (P<0.05) the nutrient digestibility. Thus, milk replacer feeding during pre-weaning has significant influence on weight gain, feed efficiency and nutrient utilization; however, the influence of probiotic feeding on lamb growth needs further studies.

96 Follicular Fluid and Serum Biochemical Composition in Alpacas (Vicugna pacos) with Different Nutritional Planes

The importance of nutrition on composition of follicular fluid and oocyte quality is recognised in several species but limited information is available on alpacas and would explain the high rate of early embryo mortality. The aim of this study was to analyse the biochemical composition of serum and follicular fluid (FF) from alpacas (Vicugna pacos) with different nutritional planes. Twelve adult female alpacas between 6 and 8 years old were assigned randomly to either a high (n = 6) or low (n = 6) plane of nutrition. Nutritional planes were defined by the grazing condition of the natural pasture with (high) or without (low) supplementation with 200 g of concentrate/day (total digestible nutrients: 52%, protein: 16%, and metabolizable energy: 2.8 Mcal kg−1). The nutritional conditions were imposed 1 month before the start of the experiment.The concentrations of total glucose, cholesterol, triglycerides, and proteins were determined with a semi-automatic biochemical analyzer (SINOWA, China). When an ovulatory follicle ≥7 mm was detected by ultrasonography using a 5-MHz linear-array transducer (SSD-500, Aloka, Tokyo, Japan), a transvaginal transducer with an attached needle guide (UST-945BP-5, Aloka) was used to collect follicular fluid. Follicular puncture was performed using a disposable 19-gauge # 12 mm hypodermic needle connected to a 50-mL conical tube via a silicon tube. A caudal epidural anaesthesia was induced with 4 mL of 2% lidocaine. Blood samples were obtained by jugular venipuncture into serum vacutainers and kept at room temperature for 30 min. Follicular fluid and serum were centrifuged at 1500 × g for 20 min, decanted, and stored at –20°C until analysed. Results were analysed by Student’s t-test. The results are presented in Table 1. The results suggest differences in biochemical composition of glucose and cholesterol in follicular fluid, which could explain the oocyte quality and embryo survival in alpacas. Table 1.Biochemical composition of follicular fluid (FF) and serum from alpacas (Vicugna pacos) under 2 nutritional planes Research was supported by INNOVATE PERU Grant 405-PNICP-PIAP-2014.

Animal performance and economic implications of alternative production systems for dairy bulls slaughtered at 15 months of age

AbstractThe objectives of this experiment were to investigate (i) the influence of varying levels of concentrate supplementation during the grazing season, (ii) alternative finishing strategies for dairy bulls slaughtered at 15 mo of age and (iii) economic implications of these management strategies. Bulls were assigned to a 2 (level of concentrate supplementation during the grazing season: 1 kg [LA] and 2 kg [HA] dry matter [DM]/head daily) × 2 (finishing strategies: concentrates ad libitum group [AL] or grass silage ad libitum plus 5 kg DM of concentrates/head daily group [SC]) factorial arrangement of treatments. Average daily gain (ADG) during the grazing season was greater (P &lt; 0.01) for HA than for LA. Consequently, HA bulls were 16 kg heavier at housing: 214 and 230 kg, respectively (P &lt; 0.05). During the finishing period, ADG tended (P = 0.09) to be greater for LA than for HA. Carcass weight tended (P = 0.08) to be greater for HA than for LA. Fat score was greater for HA. Live weight at slaughter (P &lt; 0.001) and carcass weight (P &lt; 0.001) were 41 and 23 kg greater for AL than for SC, respectively. Conformation (P &lt; 0.05) and fat score (P &lt; 0.05) were greater for AL than for SC. The Grange Dairy Beef Systems Model simulated whole-farm system effects of the production systems. Net margin/head was greater for LA than for HA and greater for SC than for AL. Sensitivity analysis of finishing concentrate price, calf purchase price and beef price showed no re-ranking of the systems on a net margin basis. Although greater animal performance was observed from the higher plane of nutrition, overall profitability was lower.

Utilization of Blepharis sindica herbage in sheep feeding: Effect on nutrient utilization, rumen fermentation and plane of nutrition

Rams (36) were fed ad lib. complete feed block (CFB) in 3 groups up to 60 days. Block-1 consisted 35, 60 and 5% of concentrate, cenchrus hay and molasses respectively. In block-2 and block-3 Blepharis sindica herbage was added at 30 and 45%. Dry matter, organic matter, crude protein digestibility increased whereas ADF, cellulose decreased with Blepharis sindica incorporation. Nitrogen balance was higher in block-2 and block-3 fed rams. Total nitrogen, TCA precipitable nitrogen, ammonia level was higher and TVFA lower in SRL of rams fed block-3 and block-2. Microbial protein synthesis / kg of DOMI was higher and dry matter intake was lower in block-2 and block-3 fed rams. Due to better nutrient utilization, higher plane of nutrition and microbial protein synthesis Blepharis sindica herbage can be used in sheep feeding up to 45% after processing as CFB.

Effect of maternal dietary manipulation and in ovo injection of nutrients on the body weight gain, feed conversion ratio, development of lymphoid and digestive organs of turkey poults

An experiment was undertaken involving maternal dietary manipulation (NRC 1994-diet A or higher plane of nutrition-diet B), in ovo nutrient injection (in ovo essential amino acids- INA; linolenic acid, linoleic acid, retinol and DL-alpha-tocopherol-INFV; in ovo essential amino acids, linolenic acid, linoleic acid, retinol and DL-alphatocopherol- INAFV, sham control-S and un injected control-C) in a 2 × 4 factorial design. Turkey breeder hens (200) and viable toms (24) of 30 to 35 weeks of age of small white variety were distributed into 2 treatment groups comprising 4 replicates of 25 hens and 3 toms in each treatment. First 4 replicates were offered diet A and the other 4 replicates were maintained on a higher plane of nutrition (diet B) for 8 weeks. Fertile eggs (548) were collected and on 21st embryonic day (ED), the eggs were in ovo injected with nutrients. In ovo nutrient injected chicks had significantly better FCR compared to the control group and INA treatment poults had significantly better FCR compared to the other treatment groups throughout the experiment. Small intestine length was significantly lower in the INAFV treatment group compared to the other treatment groups. Caecal length was significantly lower in the INA treatment group compared to the un-injected control group and the INFV group. Hence, it may be concluded that in ovo injection of nutrients may have a positive effect in production indices of turkey poults.

Effect of breed, plane of nutrition and age on growth, scrotal development, metabolite concentrations and on systemic gonadotropin and testosterone concentrations following a GnRH challenge in young dairy bulls

The onset of puberty in the bull is regulated by the timing of early GnRH pulsatility release from the hypothalamus, which has been demonstrated to be affected by plane of nutrition during calf-hood. The aim of this study was to determine the effect of plane of nutrition on growth rate, scrotal development, metabolite concentrations and exogenous gonadotrophin (GnRH) induced release of luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone (TT) in pre-pubertal bulls of two contrasting dairy breeds. Holstein-Friesian and Jersey bull calves were assigned to either a high or low plane of nutrition from 3 to 49 weeks of age. Intensive blood sampling was conducted at 16, 24 and 32 weeks of age, every 15 min from 30 min prior to intravenous administration of exogenous GnRH to 135 min after. Monthly blood samples were also collected and analyzed for insulin like growth factor 1 (IGF-1), insulin, leptin, adiponectin and metabolite concentration. Insulin and IGF-1 were higher in bulls on a high plane of nutrition (P < 0.001) but were not affected by breed (P > 0.05). Leptin was not affected by plane of nutrition or breed (P > 0.05). Adiponectin tended to be higher in bulls on a high plane of nutrition (P = 0.05), but was not affected by breed (P > 0.05). Bulls on a high plane of nutrition had a greater concentration of LH in response to GnRH (P < 0.05) but there was no effect of breed (P > 0.05). FSH concentration was not influenced by breed or plane of nutrition but FSH concentrations did decrease with age (P < 0.01), while, LH was not affected by age (P > 0.05). Jersey bulls, particularly those on a high plane of nutrition, had higher TT production in the pre-pubertal period (P < 0.001). Using 28 cm as a proxy for age at puberty, bulls on a high plane of nutrition were predicted to reach puberty earlier than bulls on a low plane. In conclusion, the data clearly demonstrate that a high plane of nutrition positively affects several key nutritional and reproductive hormones which are critical to the endocrinological functionality of the hypothalamic-pituitary-testicular axis in dairy-bred bull calves.

Effect of maternal dietary manipulation and in ovo injection of nutrients on the hatchability indices, post-hatch growth, feed consumption, feed conversion ratio and immunocompetence traits of turkey poults

ABSTRACTTwo hundred turkey breeder hens and 24 viable toms of 30-35 weeks (wk) old of small white variety were distributed into 2 treatment groups having 4 replicates First four replicates were offered diet A [National Research Council. 1994. Nutrient requirements of poultry. 8th ed. Washington, DC: National Academy Press] and other four replicates were maintained on a higher plane of nutrition – diet B for 8 wk. Five hundred and fortyeight fertile eggs on 21st embryonic day were in ovo injected with nutrients (essential amino acids - INA; linolenic acid, linoleic acid, retinol and DL-alpha-tocopherol-INFV; INA + INFV-INAFV, sham control – S and un-injected control – C). INAFV poults had significantly (P < .01) higher body weight compared to other treatment groups till 8 wk of age. Total immunoglobulins in response to 1% sheep red blood cells were significantly higher (P < .01) in the INA group compared to the C group. Cell-mediated immune response was significantly higher (P < .01) in the diet B group compared to diet A group. Thus, INAFV treatment may be carried out for better posthatch growth and breeders may be maintained on higher plane of nutrition along with INA treatment to elicit better post-hatch immunity.

Effect of milk replacer and concentrate intake on growth rate, feeding behaviour and systemic metabolite concentrations of pre-weaned bull calves of two dairy breeds

Early-life nutrition affects calf development and thus subsequent performance. The aim of this study was to examine the effect plane of nutrition on growth, feeding behaviour and systemic metabolite concentrations of artificially reared dairy bull calves. Holstein-Friesian (F; n=42) and Jersey (J; n=25) bull calves with a mean±SD age (14±4.7 v. 27±7.2 days) and BW (47±5.5 v. 33±4.7 kg) were offered a high, medium or low plane of nutrition for 8 weeks using an electronic feeding system which recorded a range of feed-related events. Calves were weighed weekly and plasma samples were collected via jugular venipuncture on weeks 1, 4 and 7 relative to the start of the trial period. The calves offered a high plane of nutrition had the greatest growth rate. However, the increased consumption of milk replacer led to a reduction in feed efficiency. Holstein-Friesian calves offered a low plane of nutrition had the greatest number of daily unrewarded visits to the feeder (P<0.001). β-hydroxybutyrate (BHB) concentrations were greater in F calves on a low plane of nutrition (P<0.001). Although there was no effect of plane of nutrition, BHB concentrations in F calves increased before weaning, concomitant with an increase in concentrate consumption. Urea concentrations were unaffected by plane of nutrition within either breed. Jersey calves on a low plane of nutrition tended to have lower triglycerides than those on a high plane (P=0.08), but greater than those on a medium plane (P=0.08). Holstein-Friesian calves offered a high plane of nutrition tended to have greater triglyceride concentrations than those on a medium plane (P=0.08). Triglycerides increased from the start to the end of the feeding period (P<0.05), across both breeds. A medium plane of nutrition resulted in a growth, feeding behaviour and metabolic response comparable with a high plane of nutrition in pre-weaned bull calves of both F and J breeds.