Two experiments were conducted to determine the availability of various vitamin E (E) sources (absorbed to verxite or adsorbed to silica) in broilers. In Experiment 1, at 100 and 300 IU supplemental E, an average of 94 and 44% of E intake from verxite and silica, respectively, was excreted in the feces, but at 30 IU E, 49 and 45% of E intake was excreted in the feces. In Experiment 2 at 30 IU, 52 and 43% of E intake from verxite and silica was excreted (source, P < 0.02). Based on these results, E adsorbed to silica is more available. Two experiments were conducted to determine the relative bioavailability of organic versus inorganic sources of either Mn or Zn. In Experiment 1, Mn as MnSO4 or a Mn amino acid complex (Availa-Mn) were compared. In Experiment 2, ZnSO4 or a Zn amino acid complex (Availa-Zn) were compared. The results indicate that Availa-Mn is a more available source of Mn than MnSO4, but Availa-Zn is not as available as a source of Zn as ZnSO4. An experiment was conducted to determine the effects of organic sources of Zn, Mn, and Cu on White Leghorn pullet performance. Treatment diets consisted of a control diet with 66 ppm Zn as ZnSO4 or a combination of ZnSO4 and Availa-Zn, 66ppm Mn as MnSO4 or a combination of MnSO4 and Availa-Mn, and 10 ppm Cu as CuSO4 or a combination of CuSO4 and a Cu amino acid complex (Availa-Cu). Diets are inorganic sources (IO), organic Zn (OZ), organic Zn and Mn (OZM), or organic Zn, Mn, and Cu (OZMC). Addition of OZM increased (P < 0.08) intestinal tensile strength and increased (P < 0.06) grams of ash per bone compared with OZMC. Pullets fed OZ had a higher (P < 0.08) bone concentration of all minerals than pullets fed OZM. Total tibia Mn was decreased (P < 0.06) by OZMC, but total tibia Cu was increased (P < 0.08) by OZ addition over IO or OZM.

Investigations into the importance of the nuclear integrity of the donor cell prior to nuclear transfer (NT) are limited. In Experiment 1, the proliferative characteristics, chromosomal stability and level of histone phosphorylation in cell lines established by explants and enzymatic dissociation at different population doublings (PDs) were investigated. The cells divided at a constant rate and cell cycle length increased only at the end of the proliferative stage. The level of aneuploidies was high and remained elevated throughout the study independent of the technique used to establish the primary culture. High levels of multinucleated cells and abnormal spindle configurations were observed after prolonged time in culture. An increase in the level of phosphorylated histones occurred after extended time in culture. In Experiment 2, gene expression patterns of chromatin remodeling proteins and levels of DNA methylation and histone acetylation of cells were analyzed. Dnmt-1, MeCP-2 and HDAC-1 expression decreased shortly after establishment of the primary culture. Methylated DNA patterns changed with time in culture, while acetylated histone levels remained constant. Embryo production, developmental potential and gene expression patterns of pre- and post-hatched embryos generated using donor cells with different levels of Dnmt-1 were examined in Experiment 3. A higher proportion of 8-16 cell embryos developed to the blastocyst stage when cells with low levels of Dnmt-1 were used as donor nuclei. Day 13 NT embryos generated using donor cells with decreased levels of Dnmt-1 and able to reach the 8-16 cell stage produced a larger number of apparently normal developing embryos, larger conceptuses and higher expression of Dnmt-3a than NT embryos reconstructed using cells with elevated levels of Dnmt-1. However, abnormal gene expression of Dnmts, INFτ and MHC-1 were noted in the majority of cloned embryos indicating inefficient nuclear reprogramming and retarded embryo development. In conclusion, it is likely that the chromosomal abnormalities observed in donor cells at late PDs impair early development of cloned embryos; however, a lower Dnmt-1 content at the time of NT may facilitate the demethylation process during the first divisions resulting in higher development rates in those surviving the 8-16 cell stage.

The objective of this research was to evaluate the effects of various feed additives on growth performance of nursery pigs. An experiment was conducted in which pigs were fed a conventional Phase 1 diet containing: 1) no salmon protein hydrolysate (SPH) or spray-dried porcine plasma (SDPP); 2-3) 1.5% SPH or SDPP; 4-5) 3.0% SPH or SDPP; or 6) 1.5% SPH and 1.5% SDPP. The results of this experiment showed growth performance was unaffected by source or level of protein during any growth phase. Overall gain:feed was greater (P = 0.08) for pigs fed the 1.5% level of protein than for those fed 3.0%, but there was no difference between protein sources. A second experiment was conducted in which pigs were fed a conventional Phase 1 diet (no mammalian protein) containing: 1) no SPH or SDPP; 2-3) 1.5% SPH or SDPP; or 4) 1.5% SPH and 1.5% SDPP. All pigs were fed common Phase 2 and 3 diets. The results of this experiment showed during Phase 1, gain:feed was greater (P < 0.05) for pigs fed SDPP than for those fed SPH. During Phase 2, ADFI was greater (P < 0.05) for pigs fed SPH than for those fed the control. During Phase 3, gain was greater (P = 0.08) for pigs fed SDPP than for those fed SPH. Overall growth performance was unaffected by protein source. An experiment was conducted in which pigs were fed Phase 1, 2, and 3 diets containing: 1) control; 2-5) 10.0% Nutri-Sure (NS), ground oat groats (GOG), ground steam rolled oats (SRO), or feeding oat meal (FOM). The results of this experiment showed during Phase 1, growth performance was unaffected by diet. During Phase 2, feed intake was greater (P < 0.09) for pigs fed GOG or SRO than for those fed NS. During Phase 3, feed intake was greater (P < 0.05) for pigs fed FOM than for those fed the control. Overall gain:feed was greater (P < 0.03) for pigs fed NS or SRO than for those fed the control. The results of these experiments indicate that SPH, SDPP, NS, GOG, SRO, and FOM are adequate additions to nursery diets.

Mares of poor body condition have low plasma leptin concentrations, while obese mares have the highest concentrations. Leptin is a primary signal of body condition to the brain in other species; therefore, low leptin concentrations in thin mares could contribute to their extended anovulatory period in winter compared to obese mares. The current experiment was designed to determine whether recombinant equine leptin, administered to seasonally anovulatory mares, would induce ovarian activity and ovulation in the winter. Leptin effects on metabolism were also studied. Beginning January 7, leptin-treated mares (n = 9) received daily i.m. injections of 10 mg recombinant equine leptin in saline and control mares (n = 10) received equivalent injections of gelatin. Reproductive effects were assessed by daily blood samples and regular ultrasound examination of the ovaries. Weights were also collected routinely. In addition, mares were confined to individual pens and hay consumption was measured as a means of evaluating appetite. A 24-h period of 30-min blood sampling was used to characterize hormone patterns. Over the course of the experiment, there was no difference between groups in follicular activity, date of first ovulation, or prolactin in either daily or frequently collected blood samples. Leptin-treated mares lost more (P < 0.0001) weight than control mares in the first 31 d; however, there was no difference in appetite as indicated by 24-h hay consumption. Post-experimental analysis revealed that leptin-treated mares developed antibodies (P < 0.001) against the injected leptin beginning around d 16. Subsequent leptin treatment did not affect growth hormone secretion during the frequent blood sampling window. Leptin treatment did not affect daily triiodothyronine concentrations; however, treated mares had lower (P < 0.016) daily thyroxine concentrations than control mares. Treated mares also had a tendency (P = 0.11) to have lower insulin concentrations during the frequent sampling period. In conclusion, daily treatment with recombinant equine leptin had an immediate effect on body weight without any effect on hay consumption. Although leptin-treated mares had lower thyroxine concentrations and a tendency for lower insulin, no effect was observed on reproductive endpoints in the time period studied.

The purpose of this research was to determine if increasing levels of RBC would affect growth performance and carcass characteristics of finishing pigs and growth performance of broilers. Three experiments were conducted to determine the effect of incremental levels of red blood cells (RBC; 0 to 4% and 0 to 2%), and thus increasing levels of dietary Leu on growth performance and linear carcass measurements of finishing pigs. Our results suggest that feeding 3 or 4% RBC causes a decrease in growth performance. However, feeding 1 or 2% RBC in the diets of finishing pigs had no detrimental effects on growth performance. Three experiments were conducted to determine the effect of incremental levels of RBC (0, 0.5, 1, 2, 3, 4, 5, 6, and 7%) on growth performance of broilers fed diets with supplemental L-Arg and L-Ile (adequate) and diets with no supplemental L-Arg and L-Ile (deficient). The results of this research indicate that up to 6% RBC can be added to a broiler diet without affecting growth performance as long as the diet is supplemented with L-Arg and L-Ile. Furthermore, up to 3% RBC can be added to broiler diets without supplemental Arg and Ile with no detrimental effects on growth performance. Broilers respond quite differently in growth performance to increasing levels of RBC compared with finishing pigs.

As in vitro fertilization (IVF) becomes more acceptable for the treatment of human infertility, it is essential for clinics to have in place an optimal embryo culture system. The objective of this study was to evaluate whether freezing and storing human embryo culture medium will alter embryo post-thaw viability. In consecutive experiments, commercial culture medium was frozen at -20°C and at -80°C and stored at 4°C until its use in IVF. Each IVF-derived replicate of bovine embryos contained a laboratory control group, a fresh commercial culture medium group(s) and a frozen-thawed commercial culture medium group(s). The commercial culture medium was supplemented with 15% of BSA for days 1 through 4 of in vitro culture and on day 4 was supplemented with 9% of glucose. Embryos were cultured to day 8 of the experiment and then embryo development was evaluated and morphology was evaluated using the RED Score system. In Experiment 1, zygotes (n=2,094) were in vitro cultured in medium that had been frozen (-20°C) with storage times ranging from 3 days to 10 weeks. It was found that embryo culture medium frozen at -20°C and stored for up to 10 weeks did not cause a decrease in 8- to 16-cell embryo or blastocyst development for those embryos cultured in medium frozen for 3 days to 6 weeks over the fresh medium (0 weeks). In Experiment 2, zygotes (n=3,727) were in vitro cultured in both fresh and frozen commercial culture medium (-80°C) that was stored for 0, 1 or 2 weeks before use. This study indicated embryo culture medium frozen at -80°C stored for up to 2 weeks did not cause a decrease in 8- to 16-cell embryo or blastocyst development over that of the fresh medium (0 week). In summary, it was concluded that there was no difference in the blastocyst development rate or morphology at the end of the culture period in medium frozen at -20°C for up to 10 weeks or in medium frozen at -80°C for up to 2 weeks.

Eight Holstein calves approximately 6 months of age (mean BW 185.15 + 16.16 kg) were used in a replicated 4 x 4 Latin Square experiment to study effects of protein sources on performance of weaned dairy calves. Dietary treatments consisted of 16% CP diets with three sources of ruminally undegradable protein (RUP). Experimental diets were corn-silage based, with soybean meal (SBM) as the source of ruminally degradable protein (control) and 3 sources of RUP including heat treated soybean meal (SBM) (SoyPLUS®), animal protein blend (PRO-LAK), and extruded-expelled SBM, included at 45% of the dietary CP. The animals were fed their respective diets twice daily ad libitum. Animals were housed in individual stalls for 14 days for dietary adjustment and feed intake measurements. Steers were housed in metabolism crates during the last 4 days of each experimental period for sample collection. Total fecal and urine output was collected, weighed, and sampled for laboratory analysis of nitrogen during the 4-d collection period. On day 4 of the collection period, animals were fitted with jugular catheters. Blood samples were collected at 15-minute intervals for 6 hours for analysis of growth hormone. An additional blood sample was collected at time 0 for plasma urea nitrogen (PUN) and at 30-minute intervals for IGF-I and insulin. On day 18 of each experimental period body weight, wither height, hip height, and body length were measured. Treatment did not affect dry matter intake (P > 0.05). There were also no effects (P > 0.05) of protein source on nitrogen metabolism, PUN, or growth parameters. There was no effect (P > 0.05) of protein source on GH levels. There was no effect of RUP sources on plasma IGF-I concentrations on (P > 0.05). Treatment did not affect (P > 0.05) insulin concentrations. However, there was an affect of time on insulin concentrations (P < 0.05). There was no difference (P >0.05) among treatments in the digestibility of DM, OM, NDF, ADF, or CP. These data suggest that feeding diets with sources of RUP does not improve performance in weaned dairy calves.

Numerous studies have reported aberrant gene expression levels attributed to suboptimal in vitro culture conditions presented to embryos. Since the culture environment is a common aspect of both in vitro production (IVP) and nuclear transfer (NT), research focusing on the in vitro culture system will have the potential to improve both techniques. This study investigated the effects of different culture systems and protein sources on the developmental competence of IVP embryos measured by cleavage and blastocyst rates, cell number, and relative abundance of oct-4, nanog, connexin 43, and GLUT-1 transcripts when compared to in vivo embryos. Experiment 1 compared IVP embryos cultured in either synthetic oviductal fluid (SOFaa) or potassium simplex optimized medium (KSOMaa) supplemented with amino acids. Experiment 2 compared the same two culture systems with and without the addition of calf serum (CS). Results from both experiments indicated that despite similar developmental rates, significant differences were observed at the mRNA level. In Experiment 1, oct-4 was the only transcript to have a mean abundance level significantly higher in KSOMaa blastocysts when compared with both SOFaa and in vivo embryos. The same pattern of upregulation of oct-4 in KSOMaa or KSOMaa with CS blastocysts was noted in Experiment 2. There were no significant alterations of the ICM specific transcript nanog in either experiment. In contrast to reports by others, connexin 43 was not expressed at detectable levels in in vivo embryos analyzed in our studies. Connexin 43 was not detected in IVP blastocysts used in Experiment 1. Connexin 43 was detected in KSOMaa, SOFaa, and SOFaa with CS blastocysts in Experiment 2. Blastocysts cultured in SOFaa with CS or KSOMaa had a significant upregulation of GLUT-1 when compared with other treatments and in vivo embryos. Overall, the transcript levels of the majority of the genes analyzed were significantly altered by an in vitro culture condition. Differences continue to be observed between in vitro cultured and in vivo embryos, and until these differences are minimized, aberrations in in vitro development will continue to arise.

The purpose of this research was to determine the optimal level of crystalline amino acid (AA) supplementation that supports maximum growth performance in broilers, and to determine the Gly requirement in broilers. Treatments were replicated with a minimum of 7 pens with 6 broilers per pen. Experiments (Exp.) were conducted from 0- to 18- days (d) post-hatching in brooder batteries. Three Exp. were conducted to determine the maximum level of L-Lysâ¢HCl that could be supplemented to corn-soybean meal (C-SBM) diets without negatively affecting growth performance of broilers. The results of these Exp. indicate that broilers can achieve maximum growth performance when fed a C-SBM diet supplemented with 0.25% L-Lysâ¢HCl. Two Exp. were conducted to determine the fifth, sixth, and seventh limiting AA in a low crude protein (CP), C-SBM diet in broilers. The results of these Exp. indicate that Arg and Val may be equally limiting followed by Ile in a C-SBM diet supplemented with DL-Met, L-Lysâ¢HCl, L-Thr, and Gly. Three Exp. were conducted to determine the Gly requirement of broiler chicks fed a low CP, AA-supplemented diet. The results of this research indicate that 2.078% total Gly + Ser is required for broilers fed a C-SBM diet supplemented with 0.25% L-Lysâ¢HCl.

An asymmetric distribution of the sexes within the left and right uterine horns has been described in multiple polytocous, laboratory species. A series of experiments were conducted to evaluate the sex ratio (% male) of calves gestated in the left and right uterine horns, as well as the sex ratio of embryos originating from the left and right ovaries of cattle. In Experiment 1, the sex ratio of calves and fetuses gestated in the left and right uterine horns was investigated. The sex ratio of calves and fetuses gestated in the right uterine horn was significantly higher compared with the sex ratio of calves and fetuses gestated in the left uterine horn. In addition, the sex ratio of the left and right uterine horns differed significantly from parity. In Experiment 2, embryo transfer data were analyzed in an effort to determine if sex-specific selection pressures were applied to embryos in the uterine horn of transfer. The sex ratio of ET calves born following transfer to the left and right uterine horns was not significantly different. Similarly, the overall sex ratio of calves born in this experiment did not differ significantly from parity. The sex ratio of embryos recovered from the left and right uterine horns of superovulated beef cows was evaluated in Experiment 3. The proportion of male embryos collected from the right uterine horns was significantly greater than from the left uterine horns. The sex ratio of embryos recovered from the uterine horns in this experiment was not different from parity. In an effort to determine the role of interovarian communications in the sex selection process, the sex ratio of embryos recovered from unilaterally ovariectomized superovulated beef heifers was investigated in Experiment 4. The sex ratios of embryos recovered from left- and right-ovary intact heifers were not significantly different. In Experiment 5, the sex ratio of IVP embryos was evaluated. The sex ratio of the IVP embryos was significantly lower than parity and was not different between ovary of origin. In addition, length of time in maturation was determined not to influence the sex ratio.