Effect of maternal overnutrition on predisposition to insulin resistance in the foal: Foal skeletal muscle development and insulin signaling

Skeletal muscle plays an integral role in the ability of a horse to perform at high levels. Shifts in skeletal muscle development in response to maternal plane of nutrition may have substantial and lasting impacts on athletic performance and whole-body metabolism. Therefore, sixteen Quarter Horse mares were used in a completely randomized design and maintained at a body condition score (BCS) 6 until start of third trimester. On d 235 of gestation, mares were randomly assigned to receive one of two dietary treatments with a diet formulated to meet requirements during late gestation (CON; n = 8), and an overfed diet (HIGH; n = 8) where mares received an additional 40% above CON. Five h after parturition, foals were euthanized, and gluteus medius, triceps brachii, and semitendinosus were harvested for analyses. Gene expression was determined by qPCR and western immunoblotting was used to quantify total and phosphorylated forms of proteins involved in skeletal muscle metabolism with tubulin as the loading control. All data were analyzed using PROC MIXED of SAS. Foals from HIGH mares exhibited larger skeletal muscle fibers by area (P <0.05), and a shift in muscle fiber development towards type I slow twitch muscle fibers (P <0.05). Relative expression of glucose transporter 4 (GLUT4) was lower in HIGH foals compared to CON in gluteus medius (P = 0.05). Insulin receptor isoform B (INSR-B) and insulin-like growth factor 1 receptor (IGF1R) were greater in triceps brachii of HIGH foals compared to CON (P ≤ 0.03). Insulin receptor isoform A (INSR-A), however, tended to be lower in triceps brachii of HIGH compared to CON (P = 0.10). Ratios of phosphorylated to total extracellular signal-regulated protein kinase 1/2 (ERK1/2) and c-June N-terminal kinase (JNK) were higher in HIGH foals compared to CON (P ≤0.04) in gluteus medius. There were no differences observed for phosphorylated to total protein ratios in semitendinosus and triceps brachii muscles; however, total ERK1/2 tended to be elevated (P <0.10) in semitendinosus from CON foals compared to HIGH. There was no difference in phosphorylated or total protein kinase B (AKT) (P >0.14). These data indicate hypertrophy of skeletal muscle fibers and a shift towards type I slow twitch fibers in HIGH foals. Furthermore, this study identifies muscle specific changes in gene expression and downstream insulin receptor signaling, which may contribute to future metabolic abnormalities in response to maternal overnutrition.

Effect of maternal overnutrition on predisposition to insulin resistance in the foal: Maternal parameters and foal pancreas histoarchitecture

Results from previous studies indicate that maternal overnutrition during late gestation predisposes foals to metabolic disease, however, specific mechanisms resulting in disease remain unknown. Quarter Horse mares (n = 16), were randomly assigned to dietary treatments, beginning on gestational day 235, and consisted of a control group (CON- diet meeting nutrient requirement; n = 8) or an overfed diet (HIGH; n = 8) where mares received an additional 40 % above CON. On gestational days 285 and 315, an intravenous glucose tolerance test (FSIGTT) was conducted. Following parturition, foals were separated from the mare, prohibited from nursing, and an FSIGTT was conducted at 2 h postpartum. Foals were immediately euthanized and tissues preserved for analyses. There was no effect of treatment on foal BW (P = 0.50), pancreas weight (P = 0.60), or FSIGTT area under the curve for glucose (P = 0.80) and insulin (P = 0.70). Colocalization of α-amylase to isolate pancreatic islets of Langerhans indicated increased islet number and size in foals from HIGH mares (P < 0.01). Immunofluoresent analysis of insulin, glucagon, and somatostatin indicate no difference in intensity of staining (P> 0.10). Foals exposed to overnutrition during peak fetal growth had altered pancreatic islet development that may lead to adult-onset metabolic disease.

Effects of maternal nutrition and rumen-protected arginine supplementation on ewe performance and postnatal lamb growth and internal organ mass

The hypothesis of this study was that arginine supplementation would overcome negative effects of restricted maternal feed intake during the last two-thirds of gestation on ewe performance and positively affect postnatal lamb growth and development. Multiparous, Rambouillet ewes (n = 32) were allocated to 3 treatments in a completely random design at 54 ± 3.9 d of gestation. Dietary treatments were 100% of nutrient requirements (control, CON), 60% of control (restricted, RES), or RES plus a rumen-protected arginine supplement dosed at 180 mg/kg BW once daily (RES-ARG). Ewes were penned individually in a temperature-controlled facility. At parturition, lambs were immediately removed from dams and reared independently. At day 54 ± 3 of age, lambs were stunned using captive bolt, exsanguinated, and organs were collected and weighed. Ewe BW from day 68 of gestation through parturition was greater (P ≤ 0.03) in CON compared with RES or RES-ARG. Similarly, ewe BCS from day 68 of gestation through parturition was greater (P ≤ 0.03) in CON than either RES or RES-ARG. Total ewe colostrum mass (g) at 3 h after parturition was greater (P ≤ 0.001) in CON than RES or RES-ARG. Lamb birth weight was greater (P = 0.04) in CON than RES ewes and tended (P = 0.10) to be greater in CON vs. RES-ARG. Lambs born to CON ewes had greater (P ≤ 0.03) BW than lambs from RES ewes at 7, 14, and 33 d postpartum. On day 19, lambs from CON and RES-ARG ewes both had greater (P ≤ 0.04) BW than lambs from RES ewes (12.0 and 11.5 vs. 10.3 ± 0.41 kg, respectively). Lambs born to CON and RES-ARG ewes had greater (P ≤ 0.04) ADG than lambs from RES ewes on day 19 (355.0 and 354.0 vs. 306.4 ± 15.77 g, respectively). Lambs from CON and RES-ARG ewes also had greater (P ≤ 0.02) girth circumference than lambs from RES ewes on day 19 (55.4 and 54.6 vs. 51.3 ± 0.97 cm, respectively). On day 54, lambs from RES-ARG ewes had greater (P = 0.003) curved crown rump length than lambs from RES ewes (99.8 vs. 93.9 ± 1.28 cm, respectively). Adrenal glands in lambs from CON dams had greater (P = 0.01) mass than adrenal glands in lambs from RES dams. Livers from lambs born to RES-ARG ewes weighed more (P = 0.05) than livers from lambs born to RES ewes. These results confirm our hypothesis that arginine supplementation during the last two-thirds of gestation can mitigate offspring, but not maternal negative consequences associated with restricted maternal nutrition.

Supplementation of metabolizable protein during late gestation and fetal number impact ewe organ mass, maternal serum hormone and metabolite concentrations, and conceptus measurements

To examine the effects of maternal metabolizable protein (MP) supplementation during late gestation on serum hormone and metabolites and organ masses, multiparous ewes (n = 45) carrying singletons or twins were allotted randomly (within pregnancy group) to 1 of 3 treatments: 60% (MP60), 80% (MP80), or 100% (MP100) of MP requirements. Blood samples were drawn before the initiation of diets (day 100) and before slaughter (day 130) for chemistry panel analysis and weekly for hormone analysis including progesterone (P4) and estradiol-17β (E2). At day 130, ewe organ masses were recorded. Despite being fed isocaloric diets, MP60 ewes gained less weight throughout pregnancy compared with MP80 and MP100 ewes which were similar. Although diet did not impact E2 or P4 concentrations, ewes carrying twins had greater (P < 0.05) concentrations of both as gestation advanced. Albumin, aspartate aminotransferase, and total protein were reduced (P < 0.05) in MP60 compared with MP100 ewes near term. There was a diet by fetal number interaction (P = 0.03) for lactate dehydrogenase. Twin-carrying MP80 ewes had greater lactate dehydrogenase compared with all other groups on day 130 of gestation. Ewes that were fed MP80 had greater body weight on day 130 of gestation compared with MP60 ewes. Kidney and heart weights were lighter in MP60 ewes compared with MP80 ewes. There was a maternal diet by fetal number interaction (P = 0.05) on fetal weight per unit empty ewe body weight. In ewes carrying singletons, MP60 ewes supported less fetal weight compared with MP100. In contrast, MP60 ewes supported more fetal mass compared with MP100 ewes when carrying twins. The level of protein, and not just total energy, in the diet appears to impact some aspects of the maternal system. Moreover, it appears some measurements of mobilizing maternal body resources are enhanced in ewes carrying twins.

Influence of maternal plane of nutrition on mares and their foals: determination of mare performance and voluntary dry matter intake during late pregnancy using a dual-marker system

Thirty pregnant mares (538 to 695 kg BW; 4 to 19 yr of age) were used to evaluate the effects of plane of nutrition on DMI of hay and mare performance (BW, BCS, and rump fat) during the last third of pregnancy. Mares were divided into 4 blocks by their expected foaling date and randomly assigned within block to either a hay or concentrate plus hay diet (concentrate fed at 0.75% BW, as-fed basis) with 15 mares per treatment. Treatments began 110 d before expected foaling date (230 d of gestation) and terminated at parturition. Mares were housed by block and allowed ad libitum access to coastal Bermuda grass (C. dactylon) hay, and concentrate-supplemented mares were fed twice daily in individual stalls. Performance variables were recorded every 14 d, with the last measurements obtained before foaling being considered a prepartum measurement. To evaluate DMI of hay, a dual-marker system was used at 9, 10, and 11 mo of gestation. Titanium dioxide was dosed at 10 g for 14 d. Fecal grab samples were obtained on the last 4 d twice daily via rectal palpation at 12-h intervals with times advancing 3 h each day to account for diurnal variation and to ultimately represent a 24-h period. Fecal samples were analyzed for TiO2 using a colorimetric procedure. Fecal, concentrate, and hay samples were also analyzed for acid detergent insoluble ash. Treatment tended to influence prepartum BW (P = 0.09) and affected prepartum BCS (P < 0.01) and rump fat (P = 0.01), with hay-fed mares having decreased BW and BCS from d 0 (beginning of feeding trial or d 230 of gestation) until parturition, whereas mares fed concentrate gained BW and BCS (P < 0.01). Mares fed only hay consumed 2.3% BW of forage compared with 1.8% BW for concentrate-fed mares (P < 0.01). Regardless of treatment, month of gestation influenced forage intake (P < 0.06), with mares consuming less during the 10th month of gestation and more in the 11th month (1.9% and 2.2% BW, respectively). These data indicate that the altered plane of nutrition of mares in late gestation influenced mare performance. Furthermore, DMI of hay was influenced by both diet and month of gestation. Continued research investigating manipulation of maternal nutrition and its effects on DMI would be beneficial to completely understand the relationships of these observations.

Impacts of maternal selenium and nutritional level on growth, adiposity, and glucose tolerance in female offspring in sheep

To examine effects of maternal nutrition and Se intake on adiposity and insulin sensitivity in female offspring, treatments were imposed during gestation on 82 pregnant primiparous Rambouillet ewe lambs (52.2 ± 0.8 kg) allotted randomly to 1 of 6 treatments in a 2 × 3 factorial arrangement. Factors were adequate (9.5 μg Se·kg BW(-1)·d(-1); ASe) or high (81.8 μg Se·kg BW(-1)·d(-1); HSe) levels of dietary Se (Se-enriched yeast) and maternal nutritional intake (100% of metabolizable energy [ME] requirement [MOD], 60% of MOD [LOW], and 140% of MOD [HIGH]). Selenium treatments were initiated at breeding and global nutritional treatments at day 50 of gestation. At parturition, lambs were removed from ewes before nursing and managed similarly. Glucose tolerance tests were performed at 107 and 148 d of age. Necropsies were performed at 180 d of age. Although there was no effect of Se on maternal body condition or weight during gestation, both maternal nutritional intake and selenium treatment influenced (P ≤ 0.04) offspring growth and response to a glucose tolerance test. Female lambs from HSe ewes were heavier (P = 0.04) at birth. There were nutritional intake and Se interactions (P ≤ 0.05) on the growth rate of the lambs and their insulin response to a glucose bolus at 2 different times during growth. By 180 d, ewe lambs from HSe ewes had more (P ≤ 0.07) internal fat stores than lambs from ASe ewes. It appears that both maternal nutritional level and Se intake can influence insulin sensitivity, and maternal Se intake alone can enhance fat deposition in female offspring.

Developmental programming: the concept, large animal models, and the key role of uteroplacental vascular development

Developmental programming refers to the programming of various bodily systems and processes by a stressor of the maternal system during pregnancy or during the neonatal period. Such stressors include nutritional stress, multiple pregnancy (i.e., increased numbers of fetuses in the gravid uterus), environmental stress (e.g., high environmental temperature, high altitude, prenatal steroid exposure), gynecological immaturity, and maternal or fetal genotype. Programming refers to impaired function of numerous bodily systems or processes, leading to poor growth, altered body composition, metabolic dysfunction, and poor productivity (e.g., poor growth, reproductive dysfunction) of the offspring throughout their lifespan and even across generations. A key component of developmental programming seems to be placental dysfunction, leading to altered fetal growth and development. We discuss various large animal models of developmental programming and how they have and will continue to contribute to our understanding of the mechanisms underlying altered placental function and developmental programming, and, further, how large animal models also will be critical to the identification and application of therapeutic strategies that will alleviate the negative consequences of developmental programming to improve offspring performance in livestock production and human medicine.

Effect of selenium supplementation and plane of nutrition on mares and their foals: selenium concentrations and glutathione peroxidase

To investigate the maternal plane of nutrition and role of Se yeast on muscle Se concentration, plasma glutathione peroxidase (Gsh-Px) activity, and colostrum Se concentration in mares and their foals, 28 Quarter Horse mares (465 to 612 kg of BW, and 6 to 19 yr of age) were used in a study with a randomized complete block design. Mares were blocked by expected foaling date and randomly assigned to dietary treatments within blocks. Dietary treatments were arranged as a 2 x 2 factorial with 2 planes of nutrition, pasture or pasture + grain mix (fed at 0.75% of BW on an as-fed basis) and 2 concentrations of Se yeast supplementation (0 or 0.3 mg/kg of DMI), resulting in 4 treatments: pasture, pasture + grain mix, pasture + grain mix + Se, or pasture + Se. Mares fed diets of pasture and pasture + Se received approximately 100% of the calculated NRC (2007) DE requirements, whereas mares fed diets of pasture + grain mix and pasture + grain mix + Se received 120%. Selenium supplementation began 110 d before the estimated foaling date and treatments were terminated at parturition. Blood and muscle (biopsy) samples were collected on d 0 and then every 14 or 28 d, respectively, thereafter until parturition. Additionally, BW, BCS, and rump fat (RF) were recorded every 14 d. At parturition, colostrum, foal plasma, and foal muscle samples were collected and sampling continued every 14 d for plasma and every 28 d for muscle until d 56. Mare BW, BCS, and RF were affected by plane of nutrition (P <or= 0.02), but not by Se supplementation. Mares fed the grain mix had greater (P < 0.05) BW, BCS, and RF measurements throughout the experiment. Mare plasma, muscle, and colostrum Se concentrations were greater (P < 0.01) in mares fed Se. Mares fed the grain mix had greater plasma Se (P = 0.02) than mares on pasture alone. Mare and foal plasma Gsh-Px concentrations were not affected by treatment. Foal plasma and muscle Se concentrations were greater when dams were fed the supplemental grain mix (P = 0.04 and 0.02, respectively) and supplemental Se (P < 0.001). Results indicated that maternal plane of nutrition and Se supplementation affected mare and foal plasma, muscle, and colostrum Se concentrations, but not Gsh-Px activity.

Effect of selenium supplementation and plane of nutrition on mares and their foals: selenium concentrations and glutathione peroxidase

To investigate the maternal plane of nutrition and role of Se yeast on muscle Se concentration, plasma glutathione peroxidase (Gsh-Px) activity, and colostrum Se concentration in mares and their foals, 28 Quarter Horse mares (465 to 612 kg of BW, and 6 to 19 yr of age) were used in a study with a randomized complete block design. Mares were blocked by expected foaling date and randomly assigned to dietary treatments within blocks. Dietary treatments were arranged as a 2 x 2 factorial with 2 planes of nutrition, pasture or pasture + grain mix (fed at 0.75% of BW on an as-fed basis) and 2 concentrations of Se yeast supplementation (0 or 0.3 mg/kg of DMI), resulting in 4 treatments: pasture, pasture + grain mix, pasture + grain mix + Se, or pasture + Se. Mares fed diets of pasture and pasture + Se received approximately 100% of the calculated NRC (2007) DE requirements, whereas mares fed diets of pasture + grain mix and pasture + grain mix + Se received 120%. Selenium supplementation began 110 d before the estimated foaling date and treatments were terminated at parturition. Blood and muscle (biopsy) samples were collected on d 0 and then every 14 or 28 d, respectively, thereafter until parturition. Additionally, BW, BCS, and rump fat (RF) were recorded every 14 d. At parturition, colostrum, foal plasma, and foal muscle samples were collected and sampling continued every 14 d for plasma and every 28 d for muscle until d 56. Mare BW, BCS, and RF were affected by plane of nutrition (P <or= 0.02), but not by Se supplementation. Mares fed the grain mix had greater (P < 0.05) BW, BCS, and RF measurements throughout the experiment. Mare plasma, muscle, and colostrum Se concentrations were greater (P < 0.01) in mares fed Se. Mares fed the grain mix had greater plasma Se (P = 0.02) than mares on pasture alone. Mare and foal plasma Gsh-Px concentrations were not affected by treatment. Foal plasma and muscle Se concentrations were greater when dams were fed the supplemental grain mix (P = 0.04 and 0.02, respectively) and supplemental Se (P < 0.001). Results indicated that maternal plane of nutrition and Se supplementation affected mare and foal plasma, muscle, and colostrum Se concentrations, but not Gsh-Px activity.

Characterization of a colostrum replacer and a colostrum supplement containing IgG concentrate and growth factors

The objective of this study was to characterize absorption of colostrum replacer (CR) or supplement (CS) containing fractions of bovine plasma. Immunoglobulin concentrate (IGC) was prepared from bovine blood to a final purity of approximately 90% IgG. Blood was also processed to produce a fraction containing elevated concentrations of IGF-I and TGF-beta (GF). Both IGC and GF were spray-dried and blended with other ingredients to produce CR (30% IgG) or CS (15% IgG) containing 0 or 5% GF. Holstein bull calves were assigned to one of five treatments: 1) Pooled colostrum (MC)--1.9 L of pooled colostrum at 1 and 8 h of age to provide over 150 g of IgG; 2) Low supplement (LC)--1.9 L of CS at 1 and 8 h of age to provide 150 g of IgG; 3) Low supplement + GF (LG)--1.9 L of a CS with GF at 1 and 8 h of age to provide 150 g of IgG; 4) High supplement (HC)--1.9 L of CR at 1 h of age to provide 150 g of IgG and 1.9 L of a commercial milk replacer (MR) at 8 h of age; and 5) High supplement + GF (HG)--1.9 L of a CR with GF at 1 h of age to provide 150 g of IgG and 1.9 L of MR at 8 h of age. Apparent efficiency of IgG absorption was higher for calves fed HC and HG compared with those fed LC and LG and was lower for calves fed LG and HG compared with those fed LC and HC. IgG concentrations at 24 h were highest in calves fed MC compared with other calves and were higher in calves fed HC and HG compared to LC and LG. Calves fed LG and HG had lower IgG concentrations at 24 h of age compared with those fed LC and HC. These results indicate that 150 g of IgG provided in one dose soon after birth is superior to 150 g of IgG fed in two doses 7 h apart. Also, addition of a plasma fraction containing elevated concentrations of IGF-I and TGF-beta decreased IgG absorption in the neonatal calf.

Compromised development of calves ( ) derived from in vitro-generated embryos and transferred interspecifically into domestic cattle ( )

Advanced reproductive technologies, incuding IVF and interspecies embryo transfer, are becoming increasingly important for the preservation of endangered species. Previous attempts at interspecies transfers between Bos gaurus and Bos taurus have yielded compromised offspring. The goal of this investigation was to characterize the effects of interspecies transfer of IVF-derived embryos on subsequent neonatal outcome. To achieve this goal, fresh Bos gaurus IVF-derived embryos were transferred into Holstein (Bos taurus) recipients. Four fetuses were carried to term. Calf weight, temperature, heart rate, and respiration rate were recorded after birth. Blood samples also were obtained for determination of blood glucose, pH, packed cell volume (PCV), total hemoglobin (tHB), PO2, and PCO2. After parturition, milk production and health status of the recipients were recorded. Two calves were alive at birth, and two calves were stillborn. One of the calves that was born alive died within minutes after birth, while the other lived until approximately 26 h of age. Blood samples obtained from the calf that lived for 26 h showed it to be extremely acidotic and hypoglycemic; this calf also had marked difficulty thermoregulating. At necropsy, all calves showed evidence of in utero gasping and hypoxia, suggestive of premature placental separation. None of the recipient cows showed typical signs of impending parturition. After parturition, lactogenesis in all recipient cows was markedly decreased. On gross examination, placentae resulting from the interspecies transfers had fewer cotyledons that were also much larger in size compared to cotyledons from normal gaur placentae. Calves in this study had abnormalities consistent with those noted from previous interspecies transfers and with IVF and nuclear transfer (cloned) calves. Due to the design of this study, it is not possible to differentiate between problems resulting from the IVF process and those resulting from potential interspecies incompatibilities. However, interspecies transfers of in vitro-produced gaur embryos into Bos taurus are strongly discouraged.

Cloning of an Endangered Species (Bos gaurus) Using Interspecies Nuclear Transfer

Approximately 100 species become extinct a day. Despite increasing interest in using cloning to rescue endangered species, successful interspecies nuclear transfer has not been previously described, and only a few reports of in vitro embryo formation exist. Here we show that interspecies nuclear transfer can be used to clone an endangered species with normal karyotypic and phenotypic development through implantation and the late stages of fetal growth. Somatic cells from a gaur bull (Bos gaurus), a large wild ox on the verge of extinction, (Species Survival Plan < 100 animals) were electrofused with enucleated oocytes from domestic cows. Twelve percent of the reconstructed oocytes developed to the blastocyst stage, and 18% of these embryos developed to the fetal stage when transferred to surrogate mothers. Three of the fetuses were electively removed at days 46 to 54 of gestation, and two continued gestation longer than 180 (ongoing) and 200 days, respectively. Microsatellite marker and cytogenetic analyses confirmed that the nuclear genome of the cloned animals was gaurus in origin. The gaur nuclei were shown to direct normal fetal development, with differentiation into complex tissue and organs, even though the mitochondrial DNA (mtDNA) within all the tissue types evaluated was derived exclusively from the recipient bovine oocytes. These results suggest that somatic cell cloning methods could be used to restore endangered, or even extinct, species and populations.

Primary penile lymphoma presenting as a penile ulcer

Primary penile lymphoma is rare. The clinical manifestations can be quite subtle, which may lead to misdiagnosis. Treatments have included radical surgery, chemotherapy and radiation. We report on an 18-year-old man with primary penile lymphoma whose lesion caused prolonged diagnostic uncertainty. He was treated with chemotherapy alone, and he has had no tumor recurrence for 27 months.

Perianal Paget's disease: successful treatment with combined chemoradiotherapy. Report of a case

A case of locally extensive perianal Paget's disease is presented. Initial wide local excision, guided by frozen sections, was inadequate. Multiple punch biopsies subsequently revealed extensive circumferential involvement of the anoderm by Paget's disease, making wide local excision difficult. Therefore, the patient was treated with combined chemoradiotherapy (5000 cGy, 5-fluorouracil, and mitomycin C). Fourteen months after treatment, the patient had a complete response.