PSV-10 The effects of maternal programming on postnatal growth and inflammation in neonatal dairy bull calves

Neonatal dairy calves are highly susceptible to respiratory and digestive diseases. A mechanism that could be predisposing calves to disease is maternal programming. We hypothesized that high milk production and/or mastitis infection during gestation will 1) affect postnatal growth and development 2) cause increased inflammation in neonatal dairy bull calves. Calves (n = 45) were selected from dams classified has high producers (HI; Top 25% for herd M305; n = 7), high producers with high SCC (HIMAST; SCC test during pregnancy over 200,000 cells/mL; n = 15), moderate producers (MOD; lower 60% for herd M305; n = 17) or moderate producers with high SCC (MODMAST; n = 6). Calves were transported to the University of Rhode Island at 24 hrs of age. Body weights and body measurements (crown rump length (CRL), skull length (SL), skull width (SW), Girth, Height) were collected at 24 hrs (Initial) and at weaning (8 weeks). C-reactive protein (Abclonal, Woburn, MA) and Malondialdehyde (Abcam, Cambridge, MA) analyses were performed on plasma samples collected 72 hrs post travel. Data were analyzed in SAS using repeated measures (BW and growth measurements) and proc mixed (inflammatory biomarkers). As expected, an effect of time was observed on calf BW, CRL, SL, SW, Girth and Height (P ≤ 0.01). However, no difference in calf BW, CRL, SL, SW, Girth and Height were observed between groups (P>0.05). No effect of dam milk production and/or SCC during gestation was observed on CRP or MDA concentrations at 72 hrs post travel (P ≥ 0.17). In conclusion, high maternal milk production and/or mastitis infection during gestation does not affect calf BW and body measurements when analyzed overtime. Correlation analyses will be performed to better understand the relationship between maternal programming and calf growth. Additional inflammatory biomarkers are also going to be evaluated.

PSI-8 Determining the effect of dam milk production and mastitis infection during pregnancy on blood biochemistry in dairy bull calves

Maternal programming can affect offspring health postnatally. We hypothesized that high milk production and/or mastitis infection during pregnancy will adversely affect calf blood biochemical analytes. Holstein bull calves (n = 45) were transported to the University of Rhode Island within 24 hrs of birth. Calves were classified by dam production and somatic cell counts (SCC) during pregnancy; HI (top 25% for herd M305, n = 7), MOD (lower 60% for herd M305, n = 16), HIMAST (HI with SCC ≥ 200,000 cells/mL; n = 15), and MODMAST (MOD with high SCC; n=6). Calves were sampled once a week for 8 wks. Serum was sent to the Missouri State Veterinary Medical Diagnostic Laboratory (Columbia, MO) for analyses. Results were analyzed in SAS using proc mixed. At wk 1, Calcium (Ca) concentrations were greater in HI calves (11±0.61mg/dL; P =.05) than MOD calves (10± 0.25mg/dL). At wk 3, Ca concentrations were greater in HIMAST (10± 0.13mg/dL) compared to HI (8±.048mg/dL; P<0.01) and MOD (9±0.36mg/dL; P =.02) calves respectively. MODMAST calves (10 ± 0.460 mg/dL) exhibited greater Ca concentrations than HI calves (P = 0.05). Aspartate aminotransferase concentrations were greater in HIMAST calves compared to MODMAST calves at wk 1 (36±2.49 Units (U)/L vs. 27±2.63U/L; P = .04) and wk 8 (79±7.08U/L vs. 47±5.71U/L; P<0.01). At wk 8, total protein concentrations were greater in HIMAST (6 ± .13g/dL) calves compared to MODMAST(5±0.13g/dL; P =.01) and MOD calves(5±.13g/dL; P = .03). In conclusion, maternal mastitis infection and production level during pregnancy does affect key circulating factors in the offspring. Correlation and gene expression analyses will be performed to better understand these changes.

PSII-19 The Effects of Maternal Programming on Dairy Bull Calf Response to an Intravenous Glucose Tolerance Test

Calves are prone to health issues with high mortality observed during the first 3 weeks of life. We hypothesized that dam milk production levels and/or mastitis infection during gestation will lead to reduced insulin production and increased circulating glucose concentration in response to an Intravenous Glucose Tolerance Test (IVGTT) in young dairy bull calves. Calves (n = 45) were selected from dams classified has high producers (HI; Top 25% for herd M305; n = 7), high producers with high somatic cell count (SCC; HIMAST; SCC test during gestation over 200,000 cells/mL; n = 15), moderate producers (MOD; lower 60% for herd M305; n =17) or moderate producers with high SCC (MODMAST; n = 6). IVGTT were performed on the calves at 7 weeks of age. Blood samples were collected prior to (-30, -15 and 0 min) infusion of glucose. After glucose (0.15 grams /kg bw) administration, samples were collected at 2, 5, 10, 15, 30, 60, and 120-minutes post infusion. Serum insulin and glucose concentrations were determined at Cornell Veterinary Medical Diagnostic Laboratory (Ithica, NY). Data were analysed in SAS using Proc Mixed. Insulin:glucose ratio was analysed using Proc Mixed with repeated measures for treatment x time. No effect of maternal milk production and/or mastitis infection during gestation was observed on calf baseline insulin, insulin AUC, baseline glucose or glucose AUC (P ≥ 0.12). Similarly, no difference in Insulin:Glucose ratio was observed in these calves (P = 0.66). In conclusion, high maternal milk production and/or mastitis infection may not have an effect on circulating insulin production in calves in response to an IVGTT. Correlation analyses will be performed on these data, as well as additional analyses, to determine if insulin sensitivity or response (ie: phase 1 response) was altered further.

TYROSINE KINASE GENE POLYMORPHISMS ASSOCIATE WITH FRESH SEMEN QUALITY FROM DAIRY BULL FRIESIAN HOLSTEIN

This research aims to identify polymorphisms in TEK genes to identify any related possibility to fresh semen quality of FH bull using the PCR method. A total of 14 samples of bull’s whole blood were collected and also the quality of each bull’s fresh semen. DNA amplification was carried out using primer Forward (TEK_F) 5'-TAGATTGTCGCTTGCCTGGG-3 'and Reverse (TEK_R) 5'-CCTGTGCCGACAGGTTTACT-3'. Analysis of the DNA sequence results was carried out using BioEdit and NCBI BLAST software. The results showed that of the 7 samples producing 262 bp and found polymorphisms in the TEK gene sequence in 23 gene bank databases. In the analysis of the relationship between the motility of individual spermatozoa with mutations, r count> r table (0.806> 0.754) or significance value <5% significance level (0.029 <0.050). In the analysis of the relationship between semen concentration and mutation, r count> r table (0.897> 0.754) or significance level <5% significance level (0.006 <0.050) is obtained.

Effects of Exogenous Glucocorticoid Administration on Appetitic Center Brain Development in Dairy Bull Calves

The objective of study was to determine the effects of exogenous cortisol on leptin concentrations and appetitic center development of perinatal dairy bull calves. Holstein bull calves (n = 27) were weighed and randomly assigned to treatments within 4 h of parturition (d0). Each calf was intravenously infused with either a low cortisol (LC; n = 9, 3.5 ug/kg of BW), high cortisol (HC; n = 9, 7.0 ug/kg of BW), or a sham infusion control (CON; n = 9, similar volume of saline). Each calf was administered a second infusion (half dose) of its respective treatment 24 h postpartum. All calves were housed similarly and fed milk replacer (28% CP, 20% fat) three times daily. Blood was collected via jugular venipuncture before infusion and from d 0–5 of age. At 5 d of age, calves were euthanized via sodium pentobarbital overdose. Cerebral-spinal fluid (CSF) from the third ventricle of the brain, hypothalamus, and adipose tissue (AT; omental, perirenal, and mesenteric) were collected. Blood and CSF samples were analyzed for leptin concentrations via a validated RIA. Adipose tissue samples were analyzed via western blotting for leptin and glucocorticoid receptor (GR) expression and normalized to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression. Hypothalamus samples were analyzed via qRT-PCR for genes associated with neuronal growth factors and normalized to the average of two housekeeping genes. All data were analyzed via ANOVA or repeated measures analysis using appropriate models (SAS Institute Inc., Cary, NC). Serum and CSF leptin concentrations were decreased (P &lt; 0.013) in HC and LC compared to CON. Leptin protein expression was decreased (P &lt; 0.044) in perirenal and omental AT of LC calves compared to CON. Hypothalamic expression of BDNF, FGF1, and FGF2 were decreased (P &lt; 0.006) in HC and LC compared to CON. In summary, exogenous cortisol administered to calves at birth reduced leptin concentrations and altered appetitic control center development of the brain.

Effect of semen extender supplementation with sericin on post-thaw dairy bull sperm quality and lipid peroxidation

Silk sericin plays a protective role in a variety of mammalian cells during cryopreservation. This study aimed to determine the effects of sericin supplementation to a freezing extender on sperm quality and lipid peroxidation in dairy bull sperm cryopreservation. Each semen sample of five Holstein-Friesian crossbred bulls was divided into four aliquots and diluted in a tris-egg yolk extender supplemented with different concentrations of sericin [0%, 0.25%, 0.5%, and 1.0% (wt/vol)]. Sperm motility (CASA), viability, acrosome integrity, mitochondrial membrane potential (fluorescent staining) and lipid peroxidation (malondialdehyde – MDA test) were analysed. The results show that the 0.25% and 0.5% sericin groups had the highest total sperm motility (P &lt; 0.05). Sperm viability, acrosome integrity, and mitochondrial function were higher in the group supplemented with 0.25% sericin compared to the control and 1.0% (P &lt; 0.05). Sericin supplementation with 0.25% and 0.5% significantly decreased MDA concentrations compared with the control (P &lt; 0.05). In conclusion, supplementation of the semen freezing extender with sericin at the concentration of 0.25% significantly improved the post-thaw semen quality and reduced lipid peroxidation in Holstein-Friesian crossbred bulls.