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Decamethylcyclopentasiloxane (D5) is used in personal care products and industrial applications. The authors summarize the risks to the environment from D5 based on multiple lines of evidence and conclude that it presents negligible risk. Laboratory and field studies show that D5 is not toxic to aquatic organisms or benthic invertebrates up to its solubility limit in water or porewater or its sorptive capacity in sediment. Comparison of lipid-normalized internal concentrations with measured concentrations in benthos indicates that field-collected organisms do not achieve toxic levels of D5 in their tissues, suggesting negligible risk. Exposure to D5 resulted in a slight reduction of root biomass in barley at test concentrations 2 orders of magnitude greater than measured D5 levels in biosolids-amended soils and more than twice as high as the maximum calculated sorptive capacity of the soil. No effects were observed in soil invertebrates exposed to similar concentrations, indicating that D5 poses a de minimis risk to the terrestrial environment. High rates of metabolism and elimination of D5 compared with uptake rates from food results in biodilution in the food web rather than biomagnification, culminating in de minimis risk to higher trophic level organisms via the food chain. A fugacity approach substantiates all conclusions that were made on a concentration basis

Amaç: Çalışmanın amaçları, holştayn ırkı ineklerin rasyonuna 90 gün boyunca zenginleştirilmiş balık yağı formunda uzun zincirli omega-3 çoklu doymamış balık yağı katılmasının veya ovulasyon günü ve 11 gün sonrasında iki kere inek somatotropin enjeksiyonunun endometriumunda PPAR ekspresyonu ve aktivasyonunu araştırmaktır. Gereç ve Yöntem: Laktasyonda olmayan inekler siklik, siklik-bST, gebe veya gebe-bST olmak üzere 4 gruba ayrıldı. Laktasyondaki inekler ise siklik, siklik-bST, gebe, gebe-bST, siklik-FO veya siklik-FO-bST olmak üzere 6 gruba ayrıldı.Bulgular: Northern ve Western blot analizleri PPARα ve PPARδ’nın ovulasyon sonrası 17. günde endometriumda ekspre edildiğini belirlendi ancak PPARγ tespit edilemedi. bST uygulaması sadece gebelerde PPARδ mRNA ekspresyonunu arttırdı, bu etki embriyo tarafından düzenlenmiş olabilir. Laktasyondaki gebe ineklerin endometriumundaki bST’ya bağlı PPARα mRNA miktarındaki artış bST etkisinin gebelik durumuna bağlı olduğunu vurgulamaktadır. Rasyona balık yağı eklenmesi PPARδ mRNA miktarını azaltırken, PPARα mRNA miktarı üzerine bir etkisi olmadı. PPARδ proteini luminal epitelde, glandular epitelde, subepitel stromada ve az miktarda da adluminal stromada belirlendi. Anti-PPARδ reaksiyonu bST uygulaması ve balık yağı beslemesine bağlı olarak gebe ineklerde azaldı. Öneri: bST uygulaması ve balık yağı beslemesi endometrialPPARα ve PPARδ ekspresyonun laktasyondaki sütçü ineklerde etkilemektedir., Aim: The study objectives were to determine whether dietary supplementation with long chain omega-3 polyunsaturated fatty acids in the form of enriched fish oil (FO) for 90 days or treatment with bovine somatotropin (bST) at the time of ovulation and 11 days post-ovulation influenced PPAR expression and activation in bovine endometrium in Holstein cows.Materials and Methods: Non-lactating cows were assigned to one of four treatments: cyclic, cyclic-bST, pregnant or pregnant-bST. Lactating cows were assigned to one of six treatments: cyclic, cyclic-bST, pregnant, pregnant-bST, cyclic-FO or cyclic-FO-bST.Results: Northern and Western blot analyses indicated that PPARα and PPARδ, but not PPARγ, are expressed in endometrium from all cows at day 17 post-ovulation. Treatment with bST is associated with increased PPARδ mRNA abundance in pregnant but not cyclic cows, suggesting that the effect may be mediated by the embryo. Increased abundances of PPARα mRNA are observed in response to bST during pregnancy in lactating cows but not in non-lactating cows, highlighting the importance of lactation status in determining bST response. Fish oil supplementation is associated with reduced PPARδ mRNA abundance, but did not affect steady-state PPARα mRNA abundance. PPARδ protein is expressed in the luminal epithelium, glandular epithelium, subepithelial stroma and to a lesser extent in the adluminal stroma. Anti-PPARδ reactivity is reduced in response to bST and fish oil treatments in pregnant cows.Conclusion: bST and fish oil treatments affect endometrial PPARα and PPARδ expression in lactating dairy cows.

The objectives of this study were to determine the association between mild fatty liver and -carotene (BC), retinol (ROL), and -tocopherol (AT) status. Multiparous Holstein cows were defined as having mild fatty liver using a threshold of 2% liver triacylglycerol (TAG, wet basis) at day (d) 2 after calving. Cows with mild fatty liver decreased dry matter intake (DMI) as a % of body weight (BW) from calving to 5th week (wk) of lactation (3.47 vs. 3.99, P = 0.02) and increased plasma nonesterified fatty acids (NEFA) concentration (345.0 vs. 266.0 µeq/dL, P = 0.10) as compared to normal cows. Fatty liver tended to lower plasma ROL (0.20 vs. 0.23 µg/mL, P = 0.10), but had no effect on plasma BC, plasma AT, liver BC, and liver ROL (P > 0.12) concentrations. However, depression in liver BC at calving was very small (8.0 vs. 68.0%) for fatty liver than for normal cows. Liver AT concentrations were greater (5.5 vs. 4.0 µg/g, P = 0.06) for cows with more than 2% liver TAG concentration. Concentration of plasma NEFA was positively correlated with plasma BC concentrations (r = 0.18, P < 0.05) and negatively correlated with concentrations of plasma ROL (r = -0.36, P < 0.0001) or AT (r = -0.35, P < 0.0001). A positive direct relationship between DMI and plasma vitamins status was found to exist only for ROL and AT, which suggests that stores of ROL or AT are less labile than stores for BC. At different times from calving, liver BC concentrations were positively correlated with liver TAG concentrations in a consistent manner but, correlations among liver ROL or liver AT concentrations and liver TAG concentrations were nonsignificants. The results suggest that the regulatory role of the liver in maintaining retinol concentrations in plasma may be compromise in cows with fatty liver. Este estudio fue realizado con los objetivos de determinar la asociación entre hígado graso leve (HGL) y estatus de -caroteno (BC), retinol (ROL) y -tocoferol (AT). Para definir HGL en vacas Holstein multíparas se empleó como valor crítico el 2% de triacilgliceroles (TAG, base fresca) en el hígado al segundo día después del parto. El consumo de materia seca (CMS), como porcentaje del peso vivo, disminuyó (3,47 vs. 3,99; P = 0,02) mientras que la concentración de ácidos grasos no-esterificados (AGNE) incrementó (345,0 vs. 266,0 µeq/dL; P = 0,10), desde el parto hasta la 5ta semana de lactancia en las vacas con HGL en comparación con las vacas control. El hígado graso tuvo la tendencia a disminuir el ROL plasmático (0,20 vs. 0,23 µg/mL, P = 0,10), pero no afectó las concentraciones de BC y AT en plasma, ni las de BC y ROL hepático (P > 0,12). Sin embargo, en el parto, la caída del BC hepático fue muy pequeña (8,0 vs. 68,0%) en las vacas con HGL. Las concentraciones de AT hepático fueron mayores (5,5 vs. 4,0 µg/g, P = 0,06) en las vacas con más de 2% de TAG hepático. La concentración plasmática de AGNE tuvo una correlación positiva con las concentraciones plasmáticas de BC (r = 0,18; P < 0,05) pero negativa con las concentraciones de ROL (r = -0,36: P < 0,0001) o AT (r = -0,35; P < 0,0001) plasmático. Solo el estatus plasmático de ROL y AT evidenciaron una relación directa positiva con el CMS, lo que sugiere que los depósitos de ROL o AT son menos lábiles que los de BC. En días diferentes del postparto, las concentraciones hepáticas de BC fueron correlacionadas positivamente con las concentraciones hepáticas de TAG de una manera consistente, pero las correlaciones entre las concentraciones de ROL o AT hepático vs. las de TAG hepático no fueron significativas. Los resultados sugieren que la función reguladora del hígado para mantener las concentraciones plasmáticas de retinol puede estar comprometida en las vacas que sufren hígado graso. 399 - 408 orosendo@ucla.edu.ve Bimestral

Este estudio fue realizado con los objetivos de determinar la asociación entre hígado graso leve (HGL) y estatus de β-caroteno (BC), retinol (ROL) y a-tocoferol (AT). Para definir HGL en vacas Holstein multíparas se empleó como valor crítico el 2% de triacilgliceroles (TAG, base fresca) en el hígado al segundo día después del parto. El consumo de materia seca (CMS), como porcentaje del peso vivo, disminuyó (3,47 vs. 3,99; P = 0,02) mientras que la concentración de ácidos grasos no-esterificados (AGNE) incrementó (345,0 vs. 266,0 µeq/dL; P = 0,10), desde el parto hasta la 5ta semana de lactancia en las vacas con HGL en comparación con las vacas control. El hígado graso tuvo la tendencia a disminuir el ROL plasmático (0,20 vs. 0,23 µg/mL, P = 0,10), pero no afectó las concentraciones de BC y AT en plasma, ni las de BC y ROL hepático (P > 0,12). Sin embargo, en el parto, la caída del BC hepático fue muy pequeña (8,0 vs. 68,0%) en las vacas con HGL. Las concentraciones de AT hepático fueron mayores (5,5 vs. 4,0 µg/g, P = 0,06) en las vacas con más de 2% de TAG hepático. La concentración plasmática de AGNE tuvo una correlación positiva con las concentraciones plasmáticas de BC (r = 0,18; P < 0,05) pero negativa con las concentraciones de ROL (r = -0,36: P < 0,0001) o AT (r = -0,35; P < 0,0001) plasmático. Solo el estatus plasmático de ROL y AT evidenciaron una relación directa positiva con el CMS, lo que sugiere que los depósitos de ROL o AT son menos lábiles que los de BC. En días diferentes del postparto, las concentraciones hepáticas de BC fueron correlacionadas positivamente con las concentraciones hepáticas de TAG de una manera consistente, pero las correlaciones entre las concentraciones de ROL o AT hepático vs. las de TAG hepático no fueron significativas. Los resultados sugieren que la función reguladora del hígado para mantener las concentraciones plasmáticas de retinol puede estar comprometida en las vacas que sufren hígado graso. The objectives of this study were to determine the association between mild fatty liver and β-carotene (BC), retinol (ROL), and a-tocopherol (AT) status. Multiparous Holstein cows were defined as having mild fatty liver using a threshold of 2% liver triacylglycerol (TAG, wet basis) at day (d) 2 after calving. Cows with mild fatty liver decreased dry matter intake (DMI) as a % of body weight (BW) from calving to 5th week (wk) of lactation (3.47 vs. 3.99, P = 0.02) and increased plasma nonesterified fatty acids (NEFA) concentration (345.0 vs. 266.0 µeq/dL, P = 0.10) as compared to normal cows. Fatty liver tended to lower plasma ROL (0.20 vs. 0.23 µg/mL, P = 0.10), but had no effect on plasma BC, plasma AT, liver BC, and liver ROL (P > 0.12) concentrations. However, depression in liver BC at calving was very small (8.0 vs. 68.0%) for fatty liver than for normal cows. Liver AT concentrations were greater (5.5 vs. 4.0 µg/g, P = 0.06) for cows with more than 2% liver TAG concentration. Concentration of plasma NEFA was positively correlated with plasma BC concentrations (r = 0.18, P < 0.05) and negatively correlated with concentrations of plasma ROL (r = -0.36, P < 0.0001) or AT (r = -0.35, P < 0.0001). A positive direct relationship between DMI and plasma vitamins status was found to exist only for ROL and AT, which suggests that stores of ROL or AT are less labile than stores for BC. At different times from calving, liver BC concentrations were positively correlated with liver TAG concentrations in a consistent manner but, correlations among liver ROL or liver AT concentrations and liver TAG concentrations were nonsignificants. The results suggest that the regulatory role of the liver in maintaining retinol concentrations in plasma may be compromise in cows with fatty liver.

Los objetivos de este experimento fueron comparar los efectos del almidón, fructosanos y pectinas, descritos en este estudio como polisacáridos solubles neutro-detergente (PSND) en la cinética de digestión de la fibra neutro-detergente (FND) forrajera y en la síntesis de proteína microbiana, independientemente del pH, a través de la técnica de digestión ruminal in vi¬tro. Se fermento fibra neutro-detergente (FND) extraída de alfalfa (A), bermuda (B) y timoty (T), bien sola (C) o mezclada con inulina proveniente del tubérculo dalia (I), pectina de cítricos (P) o almidón de maíz (S) como fuentes de PSND. La proporción de FND: PSND en las muestras de las diferentes mezclas fue 60:40. Cada forraje (A, B o T) fue incubado en tandas separadas y en replicado durante 0, 2, 4, 6, 12, 18, 24, 30, 36, 48, 72, y 96 hrs. Se uso ácido tricloroacético para precipitar la proteína microbiana y la proteína cruda proveniente del substrato (APTCA) en los tratamientos por triplicado y en los blancos a las horas 0 y 24. La producción de proteína cruda microbiana (PATC) a las 24 hrs fue estimada utilizando los valores de PTCA corregidos, a través de los blancos, para cada tratamiento a las 24 hrs y los promedios de PTCA corregidos a la hora 0. La cinética de digestión de FND fue calculada fijando los datos de desaparición de FND al modelo de Mertens. El lag (h) y la velocidad de digestión fraccional (Kd; h-¹) fueron calculadas interactivamente mediante regresión no lineal en SAS, utilizando el método de Marquardt. Los resultados por tratamiento son listados en el orden C, I, P, y S. Los valores de Kd de FND fueron 0,084; 0,099; 0,049 y 0,139 para A; 0,040; 0,035; 0,026 y 0,062 para B; y 0,069; 0,077; 0,069 y 0,088 para T. Los valores de lag (horas) fueron 6,73; 7,72; 0,07 y 8,03 para A; 7,02; 7,64; 8,86 y 10,27 para B; y 6,80; 6,41, 3,71 y 7,23 para T. Los valores de PATC (mg/g de materia orgánica del substrato) fueron 32,86; 75,95; 50,62 y 59,29 para A; 29,26; 53,75; 24,70 y 51,24 para B y 40,48; 79,77; 51,30 y 68,81 para T. Los polisacáridos solubles neutro-detergente añadidos a la FND no afectaron el lag ni tampoco Kd de manera significativa (P>0,05). Los valores de APATC para las FND forrajeras que fueron incubadas con P fueron siempre menores que aquellas incubadas con I o S. Inulina y S tuvieron un efecto similar excepto en la FDN extraída de Alfalfa. Los polisacáridos solubles neutro-detergente no afectaron la cinética de digestión de FND proveniente de forrajes cuando el pH de los cultivos fue mantenido por encima de 6.6 pero si la producción de proteína microbiana in vitro. La producción de proteína microbiana in vitro promovida por los tratamientos, I y S, fué mayor que la promovida por P. The purposes of this experiment were to compare the pH-independent effects of starch, fructans, and pectins, described in this study as neutral detergent-soluble polysaccharides (NDSP), on forage neutral detergent fiber (NDF) digestion kinetics and microbial protein synthesis using the in vitro ruminant digestion technique. Isolated NDF from alfalfa (A), Bermuda grass (B), and timothy (T) was fermented alone (C) or with dahlia tuber inulin (I), citrus pectin (P), or corn starch (S) as NDSP sources. In blended samples, the NDF:NDSP ratio was 60:40. Individual forages (A, B or T) were fermented in separate duplicate runs using 0, 2, 4, 6, 12, 18, 24, 30, 36, 48, 72, and 96 h time points. Trichloroacetic acid was used to precipitate microbial and substrate crude protein in triplicate treatments and blanks at 0 and 24 h. The 24 h treatment values corrected for blank and 0 h treatment means estimated microbial crude protein yield (TCAP) at 24 h. Kinetics of NDF digestion were calculated by fitting the NDF disappearance data to the Mertens model. Both fermentation lag time (h) and the fractional rate of digestion (Kd; h-¹) were calculated iteratively by NLIN’s Marquardt procedure of SAS. Results are listed in treatment order C, I, P, and S. The NDF kd values were 0.084, 0.099, 0.049, and 0.139 for A, 0.040, 0.035, 0.026, and 0.062 for B, and 0.069, 0.077, 0.069, and 0.088 for T. Lag time (hours) values were A: 6.73, 7.72, 0.07, and 8.03; B: 7.02, 7.64, 8.86, and 10.27; and T: 6.80, 6.41, 3.71, and 7.23. The ATCAP values (mg of CP/g of substrate OM) were A: 32.86, 75.95, 50.62, and 59.29; B: 29.26, 53.75, 24.70, and 51.24; and T: 40.48, 79.77, 51.30, and 68.81. Neither the lag time nor Kd were affected by NDSP addition to forage NDF (P>0.05). The ATCAP of forage incubated with P was always less than that incubated with I and S, and the effect of both I and S were similar except for Alfalfa NDF. The neutral detergent-soluble polysaccharides did not affect kinetics of forage NDF digestion when pH of cultures was maintained over 6.6 but, they differed in their effects on microbial protein production in vitro. Overall, treatment I and S favored greater in vitro microbial protein production than P. 18 - 27 Bimestral

Pregnancy rate, a function of heat detection and conception rate, determines the number of days postpartum at which cows become pregnant from the voluntary waiting period.67 Cows expressing one or more estruses during the first 30 days postpartum had improved pregnancy rates compared with anestrous cows.83 This observation indicates that the physiological and hormonal events associated with estrus help restore uterine and ovarian function to a state conducive to pregnancy. A number of studies have demonstrated the relationship between hypocalcemia and parturient disorders such as dystocia, retained fetal membranes (RFM), and ketosis.13,30,68 These disorders predispose the cow to metritis, which can affect the energy status of the cow. This influences ovarian activity and resumption of cyclicity during the postpartum period. The energy status of the lactating dairy cow has differential effects on early follicular development and competence, ovulation and subsequent corpus luteum (CL) function during the postpartum period. As our understanding of the endocrinology and reproductive physiology of the postpartum cow has advanced, it is clear that reproductive and nutritional management systems need to be integrated to achieve optimal reproductive efficiency. Objectives of this presentation are 1) to describe the association between calcium status and periparturient disorders 2) to relate the differences in ovarian activity to energy status in postpartum dairy cows 3) to examine the effects of protein and fat on reproductive function during the postpartum period, and 4) to document the beneficial effects of bovine somatotropin (bST) on first-service pregnancy rates when integrated into a reproductive management program for timed insemination., American Association of Bovine Practitioners Proceedings of the Annual Conference, 1999