P. Soca - Academia.edu (original) (raw)
Papers by P. Soca
animal, 2014
Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gest... more Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gestation-lactation cycle in purebred (PU: Angus and Hereford) and crossbred (CR: reciprocal F1 crosses) mutliparous beef cows (n = 32), grazing on two herbage allowances of native pastures (2.5 v. 4 kg dry matter/kg BW; LO v. HI) and their associations with cow's productive performance (calf birth weight, milk production and commencement of luteal activity). Cow BW, body condition score (BCS) and blood samples were collected monthly, starting at − 165 days relative to calving (days), and every 2 weeks after calving until +60 days of lactation. Liver biopsies were collected at − 165, − 75, − 45, − 15 ± 10, and +15 and +60 ± 3 days. Metabolic, endocrine and hepatic gene expression profiles, and calf birth weight, milk yield and postpartum commencement of luteal activity were evaluated. Overall, the most pronounced changes in metabolic, endocrine and hepatic gene expression occurred during winter gestation (−165 to − 45 days), when all cows experienced the onset of a negative energy balance (decreased BCS, glucose and insulin, and increased non-esterified fatty acid concentrations, P < 0.008). Concentrations of insulin and IGF-I were greater (P < 0.037) in HI than in LO cows. However, serum IGF-I concentrations and hepatic growth hormone receptor (GHR) and IGF1 mRNA decreased (P < 0.05) during the winter gestation period only in HI cows. Although IGF-I concentrations decreased (P < 0.05) during the early postpartum (−15 v. + 15 days) for all cows, the typical molecular mechanism that control the uncoupling of the growth hormone-IGF1 axis during the transition period of the dairy cattle (reduced hepatic GHR1A and IGF-I mRNA) was not observed in this study. The hepatic mRNA expression of key transcripts involved in gluconeogenesis and fatty-acid oxidation were upregulated (P < 0.05) during winter gestation (from − 165 to − 45, − 15 or +15 days, depending on the cow groups). Particularly, acyl-CoA oxidase-1 mRNA was greater for CR than for PU cows during winter gestation (−75 and − 45 days), and fibroblast growth factor-21 mRNA was downregulated (P < 0.01) only for HI cows during the transition (−15 v. 15 days) and lactation period (+15 to +60 days, P < 0.01). These results, together with the greater BCS, estimated energy intake, increased milk yield and shorter commencement of luteal activity in HI than in LO, and in CR than in PU cows (P < 0.018), would indicate that HI and CR cows were able to adapt more efficiently to changes in nutrient and energy supply through the gestation-lactation cycle.
Chilibroste, P., Soca, P., . Genera el ayuno, señales que modifiquen el comportamiento ingestivo ... more Chilibroste, P., Soca, P., . Genera el ayuno, señales que modifiquen el comportamiento ingestivo y la performance productiva en vacunos ?. In: XXXIII Jornadas Uruguayas de Buiatría. Gil, J., Olivera, J. y Gianneechini, E. Eds. Pp.111-120.
... Aut. Analit.: Soca, P; Rodríguez Irazoqui, Marcelo; Olivera, Julio; Villegas, N; Claramunt, M... more ... Aut. Analit.: Soca, P; Rodríguez Irazoqui, Marcelo; Olivera, Julio; Villegas, N; Claramunt, M. Título: Efecto de la suplementación energética de corta duración y el destete temporario sobre el tamaño folicular y preñez temprana de vacas primíparas en anestro, P. Soca ... [et al.]. ...
Annales de Zootechnie, 1995
A grazing experiment was conducted on a rangeland (mainly Stypa ssp, Paspalum ssp) oversowed with... more A grazing experiment was conducted on a rangeland (mainly Stypa ssp, Paspalum ssp) oversowed with Lotus corniculatus L. at the Experimental Agronomic Station EEMAC, Uruguay, to study diet quality and to provide an understanding of how the rapid defoliation that occurs under rotational grazing affects diet selection. Four levels of forage allowance were evaluated : 5.0 ; 7.5 ; 10.0 and 12.5 kg DM/ 100 kg LW/ day, using 24 yearlings Holstein steers as fixed experimental animals. Forage allowance was adjusted using the Put and Take technique in a rotational grazing system, (7 grazing days and 35 days resting period), using 6 paddocks for each treatment. Diet were collected from all treatments on 10 occasions over 9-month period (winter, spring, summer) using 5 esophageacally fistulated steers. Dietary quality was assessed on the lst, 4th and 7th grazing day determining crude protein (CP), in vitro organic matter digestibility (IVOMD) and neutral detergent fiber (NDF) of extrusa samples in each collection. Biting rate (BR, mean number of bites during 1 min, measured on three times per collection) and bite weight (BW, dry weight of extrusa collected divided by the number of bites taken per collection) were measured concurrently. Diet selection was assessed by difference of forage available quality and extrusa quality on the 1 st grazing day.
Animal Production Science, 2016
ABSTRACT
animal, 2014
Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gest... more Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gestation-lactation cycle in purebred (PU: Angus and Hereford) and crossbred (CR: reciprocal F1 crosses) mutliparous beef cows (n = 32), grazing on two herbage allowances of native pastures (2.5 v. 4 kg dry matter/kg BW; LO v. HI) and their associations with cow's productive performance (calf birth weight, milk production and commencement of luteal activity). Cow BW, body condition score (BCS) and blood samples were collected monthly, starting at − 165 days relative to calving (days), and every 2 weeks after calving until +60 days of lactation. Liver biopsies were collected at − 165, − 75, − 45, − 15 ± 10, and +15 and +60 ± 3 days. Metabolic, endocrine and hepatic gene expression profiles, and calf birth weight, milk yield and postpartum commencement of luteal activity were evaluated. Overall, the most pronounced changes in metabolic, endocrine and hepatic gene expression occurred during winter gestation (−165 to − 45 days), when all cows experienced the onset of a negative energy balance (decreased BCS, glucose and insulin, and increased non-esterified fatty acid concentrations, P < 0.008). Concentrations of insulin and IGF-I were greater (P < 0.037) in HI than in LO cows. However, serum IGF-I concentrations and hepatic growth hormone receptor (GHR) and IGF1 mRNA decreased (P < 0.05) during the winter gestation period only in HI cows. Although IGF-I concentrations decreased (P < 0.05) during the early postpartum (−15 v. + 15 days) for all cows, the typical molecular mechanism that control the uncoupling of the growth hormone-IGF1 axis during the transition period of the dairy cattle (reduced hepatic GHR1A and IGF-I mRNA) was not observed in this study. The hepatic mRNA expression of key transcripts involved in gluconeogenesis and fatty-acid oxidation were upregulated (P < 0.05) during winter gestation (from − 165 to − 45, − 15 or +15 days, depending on the cow groups). Particularly, acyl-CoA oxidase-1 mRNA was greater for CR than for PU cows during winter gestation (−75 and − 45 days), and fibroblast growth factor-21 mRNA was downregulated (P < 0.01) only for HI cows during the transition (−15 v. 15 days) and lactation period (+15 to +60 days, P < 0.01). These results, together with the greater BCS, estimated energy intake, increased milk yield and shorter commencement of luteal activity in HI than in LO, and in CR than in PU cows (P < 0.018), would indicate that HI and CR cows were able to adapt more efficiently to changes in nutrient and energy supply through the gestation-lactation cycle.
Livestock Science, 2014
ABSTRACT The objective was to determine effects of prepartum BCS on metabolic/endocrine profiles ... more ABSTRACT The objective was to determine effects of prepartum BCS on metabolic/endocrine profiles and hepatic gene expression and their associations with cow and calf performance in grazing suckled-primiparous beef cows from −49 to 49 days postpartum (DPP). Twenty crossbred cows selected according to expected calving date, were classified at −35 DPP into thin (BCS<4.5) or moderate (BCS≥4.5) BCS groups and blocked by calving date. Blood samples were obtained weekly for metabolite and hormone analyses and liver biopsies were collected at −11, 7, 31, and 49 DPP. Cow BW and BCS were greater in moderate than thin cows throughout the period. Estimated energy intake was greater in moderate than thin cows Moderate BCS cows produced more milk than thin cows at 35 DPP and calves from moderate BCS cows had greater BW and average daily gain than calves from thin cows. Serum leptin tended to be greater while adiponectin was less in moderate than thin BCS cows. Overall serum insulin was less in moderate than thin cows while serum IGF-I during the prepartum was greater in moderate than thin BCS cows. Growth hormone receptor (GHR) mRNA was 2-fold greater at −11 DPP while GHR1A and IGF1 mRNA were 2.5-fold less at 49 DPP in moderate than thin BCS cows. The IGFBP2 mRNA decreased in moderate but increased in thin BCS cows from −11 to 49 DPP. These results were associated with changes in body reserves during prepartum and may indicate that prepartum differences in BCS lost can affect nutrient partitioning towards the mammary gland, and subsequent milk production and calf weight.
Animal Feed Science and Technology, 2012
Effects of daily herbage allowance (DHA) on milk production and composition, body condition score... more Effects of daily herbage allowance (DHA) on milk production and composition, body condition score (BCS) and grazing behavior of primiparous Holstein cows during early lactation were investigated. Cows were blocked by body weight (BW), age and BCS, and randomly assigned within block to one of three grazing treatments (n = 11 cows each) being: high (HA, 30 kg DM/cow/d), medium (MA, 15 kg DM/cow/d) and low (LA, 7.5 kg DM/cow/d) DHA. Cows were grazed in 8 consecutive grazing paddocks (GP) of 7 d of occupation each. The experiment was a completely randomized block design and data were analyzed as repeated measurement in time. Milk production was higher in HA and MA groups than in LA (24.3 and 22.7 vs. 19.2 L, P<0.01 respectively). Milk response to extra DHA was 0.43 L of milk/kg DHA between LA and MA treatments, which dropped to 0.19 L of milk/kg between LA and HA treatments. Cows in the HA treatment had higher BCS than cows in MA and LA treatments (3.18 vs. 3.05 and 3.07; P<0.05). Cows on all treatments mobilized BCS during the first 3 weeks after calving but, while HA cows lost ∼0.5 points of BCS, LA cows lost 1 point. The probability of a cow grazing at any time increased (P<0.01) as the experiment progressed, being 54.5, 61.3, 66.8 and 68.7 min/100 min for GP 3, 5, 7 and 8, respectively. Probability of grazing increased linearly for cows receiving HA (0.39 min/100 min/d) and MA (0.44 min/100 min/d) treatments at higher rate than cows receiving LA (0.22 min/100 min/d) treatment. A linear effect of days in milk (DIM) on bite rate as well as an interaction of DIM by treatment occurred. At DIM = 0, the mean value for bite rate was ∼15 bites/min, and the slope relative to DIM was higher for HA and MA cows (0.54 and 0.69 bites/min/d, respectively) than for LA cows (0.29 bites/min/d). The result of the present experiment evidence the major role of DHA on milk production in primiparous dairy cows during early lactation, being more important at lower levels of DHA. The lack of response on milk production to higher levels of DHA might have been related to the low effective grazing time and bite rate exhibited by early lactation grazing primiparous cows.
Australian Journal of Experimental Agriculture, 2007
Animal Production Science, 2013
The objective of the present experiment was to analyse the effect of body condition score (BCS) a... more The objective of the present experiment was to analyse the effect of body condition score (BCS) at calving, type of suckling restriction and flushing on metabolic and endocrine profiles, and productive and reproductive responses of primiparous beef cows grazing native grassland. Primiparous beef (n = 56) cows in anestrus classified by BCS at calving (low 3.5 and moderate !4; 1-8 visual scale) were assigned randomly to four treatments in a two by two factorial arrangement of type of suckling restriction and flushing. Type of suckling restriction started at 55 AE 10 days postpartum (DPP AE s.e.m.; Day 0 = initiation of the treatment) and consisted of applying nose plates to calves for 12 days (i.e. TS treatment) or 5 days of isolation of the cow-calf pair, followed by applying nose plates to calves for 7 days as calves were reunited with their mothers (i.e. IS treatment). Immediately after the suckling restriction treatments were finished, the breeding season started, and each cow received (flushing group) or not (control group) 2 kg/day (fresh basis) of whole-rice middling for 22 days. The BCS was superior in moderate-BCS cows through the experiment. The type of suckling restriction did not affect any plasma parameter, but insulin-like growth factor I (IGF-I) concentrations increased in all cows during suckling restriction. Cholesterol concentration was affected by flushing · day interaction (P < 0.05), while insulin and IGF-I concentrations were affected by the interaction among BCS at calving, flushing and days (P < 0.03). Flushing increased cholesterol concentration in both BCS groups at calving, while insulin and IGF-I concentrations increased during flushing only in moderate-BCS cows. Suckling restriction, flushing, and BCS at calving did not affect calf weight or milk production. Moderate BCS cows had a shorter postpartum anestrous interval (PPI) (98 vs 123 DPP; P < 0.01). Isolated type of suckling reduced postpartum anestrous interval when compared with TS treatment (97 vs 115 DPP, P < 0.05). Early pregnancy rate was greater in flushed than in control cows (0.8 vs 0.55, P < 0.01) and in moderate-BCS cows than in low-BCS cows (0.84 vs 0.46, P < 0.01). Total pregnancy rate was also greater in flushed and moderate cows and tended to be affected by the interaction between flushing and BCS at calving (P = 0.06; flushed cows: moderate = 1 vs low = 0.5, P < 0.08; and control cows: moderate = 0.8 vs low = 0.4, P < 0.09). These results confirmed the great value of suckling restriction and flushing during post-calving and relevance of BCS at calving as a link between energetic nutrition and metabolic and reproductive processes in primiparous beef cows grazing native grassland.
Animal Production Science, 2015
Research conducted over recent decades to improve understanding of the functional responses among... more Research conducted over recent decades to improve understanding of the functional responses among sward characteristics, intake rate and grazing behaviour has been reviewed. The opportunities to modify grazing pattern by changes in feeding management are discussed and the implications for dairy-farm feeding strategies are highlighted. Progress in the understanding of the functional responses between sward characteristics and intake rate and their main components (bite mass, bite area, bite depth and bite rates) has been substantial. However, progress in understanding the factors that mediate the initiation and the end of individual meals has been poorer and requires further study. Much of the research has been conducted using short-term experiments with a limited number of experimental animals and mostly conducted on mono-specific uniform swards. The physiological state of the animal as well as the maintenance energy associated with grazing strategies have received very little, if any, attention. More integrated (sward, animal, management) and long-term basic research is required to improve feeding practices at the farm level and the design of farms for the new generation of grassland-based dairy-production systems.
América Latina cuenta con aproximadamente el 25% de la población mundial de vacunos (Scherf, 1997... more América Latina cuenta con aproximadamente el 25% de la población mundial de vacunos (Scherf, 1997) y en ella coexisten países con énfasis exportador, Brasil, primer exportador a nivel mundial, Argentina, 4to, Uruguay, 7mo, entre otros (Rearte, 2007) e importadores. Sin embargo, en todos ellos la producción de carne bovina es un rubro importante del sector pecuario y la cría se realiza fundamentalmente en sistemas pastoriles sin subsidios. La región comparte una baja eficiencia reproductiva, manifestada por la baja producción de terneros destetados, y los principales problemas identificados como responsables de esa situación: la avanzada edad a primer parto y el prolongado anestro post-parto de nuestros rodeos u hatos. Uruguay no es la excepción, registros históricos indican que el promedio nacional del porcentaje de destete se ha mantenido en los últimos 20 años en el entorno del 63% con las vacas de primera cría presentando los menores porcentajes de preñez y destete (DI. CO.SE). Las fluctuaciones entre años reflejarían mayoritariamente la influencia del clima sobre la producción de forraje y energía, principal nutriente limitante del proceso de la cría. Por lo que, una de las prioridades del sistema criador uruguayo, como el de la mayoría de los países latinoamericanos, es la mejora del porcentaje de destete con alternativas de bajo costo y fácil aplicación. Cualquier opción para lograr este objetivo debe tener presente que la cría vacuna del Uruguay forma parte del sector exportador, por ende dichas prácticas deben ser compatibles con la producción de carne con denominación de origen y amigables con el medio ambiente.
Livestock Science, 2014
ABSTRACT Visceral tissues impact on the partitioning of metabolizable energy between maintenance ... more ABSTRACT Visceral tissues impact on the partitioning of metabolizable energy between maintenance and production. The aim of this study was to evaluate long-term effects of two herbage allowances of native pastures on mass, composition and expression of mitochondrial respiratory protein encoding genes on gastrointestinal tract (GIT) organs and liver in pure (Angus and Hereford, PU) and crossbred (reciprocal F1, CR) beef cows. Mature beef cows (n=32) were used in a complete randomized block design with a factorial arrangement of herbage allowance (2.5 vs. 4 kg DM/d; LO vs. HI) and cow genotype (PU vs. CR). The experiment was conducted during three years and at the end of the third year, cows were slaughtered at 190±10 d postpartum, and GIT organs and liver were dissected, weighed, and samples collected and immediately frozen. Reticulum-rumen (P=0.02) and total intestine (P=0.02) absolute mass (kg) was greater in HI than LO cows and greater in CR than PU cows, and liver (P<0.01) mass were greater in HI than LO cows. Abomasum protein content was greater (P<0.01), while omasum protein content tended (P=0.10) to be greater for HI-PU than LO-PU cows. The reticulum-rumen and abomasum lipid contents tended to be less (P<0.10) in HI than LO cows. Except for the large intestine and liver, concentration of DNA and protein:DNA ratio did not differ in GIT viscera of different cow groups. The protein:DNA ratio of the large intestine was greater (P=0.03) in HI-CR than LO-CR cows, while the hepatic protein:DNA ratio was less (P=0.04) in HI-CR than LO-CR cows while not differing of HI-PU and LO-PU cows that presented intermediate values. The small intestine expression of NDUFB8 and COX5B mRNA were greater (P<0.05) and NDUFS4 mRNA tended (P=0.06) to be greater in HI than LO cows. The expression of UQCRC1 mRNA was greater (P=0.04) and SDHA mRNA tended to be greater (P=0.08) in CR than PU cows. Hepatic NDUFB8, NDUFS4 and COX5B mRNA was greater (P<0.05) in LO-CR than HI-CR and LO-PU cows being intermediate in HI-PU cows. The CYC1 mRNA was greater (P=0.05) in LO than HI cows. These results suggest that CR cows would have greater plasticity in order to adapt their visceral mass and gene expression to sparse environments.
Journal of Animal Physiology and Animal Nutrition, 2012
ABSTRACT Sixty-four spring-calved primiparous crossbred cows paired by calving date and body cond... more ABSTRACT Sixty-four spring-calved primiparous crossbred cows paired by calving date and body condition score (BCS) at calving were used to study the effect of a short-term increase in the nutritional plane before the mating period on cow and calf performance, changes in metabolic and endocrine parameters and hepatic gene expression. At 48 ± 10 days post-partum (onset of nutritional treatment = day 0), cows were assigned to two treatments during 23 days: control (grazing of native pastures; NP; n = 31) and increased nutritional plane (NP improved with Lotus subbiflorous cv Rincon; IP; n = 33). Cow body weight (BW), BCS and total protein and albumin concentrations increased while urea and non-esterified fatty acids levels decreased from the beginning of the nutritional treatment in both groups, indicating the animal positive energy balance as forage growth and availability of pastures increased during spring. In addition, cow BW and BCS, as well as calf average daily gain and BW, were greater in IP than in NP cows groups. Insulin concentrations were less in IP than in NP (1.37 vs. 2.25 ± 0.26 μU/ml) because insulin increased owing to nutritional treatment only in NP cows. Hepatic insulin receptor mRNA at day 23 tended to be 1.5-fold greater, while insulin growth factor binding protein-3 mRNA expression was 1.7-fold greater in NP than in IP cows. Reproductive responses were not affected by nutritional treatment, but days to initiation of ovarian ciclicity (108 ± 10 days) were positively correlated with insulin concentrations. Grazing of improved NP for 23 days before the mating period did not improve cow reproductive performance but modified metabolic, endocrine and gene expression parameters, in agreement with greater nutrient and energy partitioning towards milk production, reflected in better calf performance.
Animal Production Science, 2013
The objectives of the present experiment were to analyse the reproductive and productive response... more The objectives of the present experiment were to analyse the reproductive and productive responses to sucklingrestriction treatments and flushing in primiparous grazing beef cows. During 3 years, 153 primiparous anoestrus cows were assigned randomly to one of four treatments in a 2 by 2 factorial arrangement of suckling-management treatments and flushing. Suckling-restriction treatments started at 61 AE 10 days postpartum and consisted of applying nose plates to calves for 12 days (i.e. TS treatment) or 5 days of isolation of the calf from the cow followed by applying nose plates to calves for 7 days as calves were reunited with their mothers (i.e. IS treatment). Nutritional treatments (flushing v. control) started at the beginning of the breeding season, immediately after the suckling-restriction treatments were finished (73 AE 10 days postpartum), with cows receiving or not receiving 2 kg/day of whole-rice middling for 22 days. Cow body condition score (BCS) was recorded every 20 days from calving until 120 days postpartum. Duration of postpartum anoestrus (PPA) and probability of cyclicity were estimated by plasma progesterone concentrations analysed in weekly samples. Pregnant cows were determined by ultrasound 42 days after bull introduction (early pregnancy; EP) and 30 days after the end of the breeding season (total pregnancy; TP). BCS at calving and changes in BCS from calving to the day of BCS nadir (DBCS) varied among years depending on forage availability and weather conditions. Increased cow BCS at calving decreased PPA (b = -41 days, P < 0.0001) and, in interaction with DBCS, increased EP (P < 0.008) and TP (P < 0.003). Calf weights at weaning and average daily gain were not affected by suckling-restriction or flushing treatments. Isolated temporary suckling control reduced PPA by 11 days when compared with temporary suckling control (P < 0.004). Flushing increased EP by 40%, which was also affected by BCS at calving and was greater in cows that gained, than in those that maintained or lost BCS. We conclude that flushing was useful in improving early pregnancy rates of primiparous beef cows with 'suboptimal' body condition (lower than 4.5) at calving and grazing native pasture.
animal, 2014
Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gest... more Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gestation-lactation cycle in purebred (PU: Angus and Hereford) and crossbred (CR: reciprocal F1 crosses) mutliparous beef cows (n = 32), grazing on two herbage allowances of native pastures (2.5 v. 4 kg dry matter/kg BW; LO v. HI) and their associations with cow's productive performance (calf birth weight, milk production and commencement of luteal activity). Cow BW, body condition score (BCS) and blood samples were collected monthly, starting at − 165 days relative to calving (days), and every 2 weeks after calving until +60 days of lactation. Liver biopsies were collected at − 165, − 75, − 45, − 15 ± 10, and +15 and +60 ± 3 days. Metabolic, endocrine and hepatic gene expression profiles, and calf birth weight, milk yield and postpartum commencement of luteal activity were evaluated. Overall, the most pronounced changes in metabolic, endocrine and hepatic gene expression occurred during winter gestation (−165 to − 45 days), when all cows experienced the onset of a negative energy balance (decreased BCS, glucose and insulin, and increased non-esterified fatty acid concentrations, P < 0.008). Concentrations of insulin and IGF-I were greater (P < 0.037) in HI than in LO cows. However, serum IGF-I concentrations and hepatic growth hormone receptor (GHR) and IGF1 mRNA decreased (P < 0.05) during the winter gestation period only in HI cows. Although IGF-I concentrations decreased (P < 0.05) during the early postpartum (−15 v. + 15 days) for all cows, the typical molecular mechanism that control the uncoupling of the growth hormone-IGF1 axis during the transition period of the dairy cattle (reduced hepatic GHR1A and IGF-I mRNA) was not observed in this study. The hepatic mRNA expression of key transcripts involved in gluconeogenesis and fatty-acid oxidation were upregulated (P < 0.05) during winter gestation (from − 165 to − 45, − 15 or +15 days, depending on the cow groups). Particularly, acyl-CoA oxidase-1 mRNA was greater for CR than for PU cows during winter gestation (−75 and − 45 days), and fibroblast growth factor-21 mRNA was downregulated (P < 0.01) only for HI cows during the transition (−15 v. 15 days) and lactation period (+15 to +60 days, P < 0.01). These results, together with the greater BCS, estimated energy intake, increased milk yield and shorter commencement of luteal activity in HI than in LO, and in CR than in PU cows (P < 0.018), would indicate that HI and CR cows were able to adapt more efficiently to changes in nutrient and energy supply through the gestation-lactation cycle.
Chilibroste, P., Soca, P., . Genera el ayuno, señales que modifiquen el comportamiento ingestivo ... more Chilibroste, P., Soca, P., . Genera el ayuno, señales que modifiquen el comportamiento ingestivo y la performance productiva en vacunos ?. In: XXXIII Jornadas Uruguayas de Buiatría. Gil, J., Olivera, J. y Gianneechini, E. Eds. Pp.111-120.
... Aut. Analit.: Soca, P; Rodríguez Irazoqui, Marcelo; Olivera, Julio; Villegas, N; Claramunt, M... more ... Aut. Analit.: Soca, P; Rodríguez Irazoqui, Marcelo; Olivera, Julio; Villegas, N; Claramunt, M. Título: Efecto de la suplementación energética de corta duración y el destete temporario sobre el tamaño folicular y preñez temprana de vacas primíparas en anestro, P. Soca ... [et al.]. ...
Annales de Zootechnie, 1995
A grazing experiment was conducted on a rangeland (mainly Stypa ssp, Paspalum ssp) oversowed with... more A grazing experiment was conducted on a rangeland (mainly Stypa ssp, Paspalum ssp) oversowed with Lotus corniculatus L. at the Experimental Agronomic Station EEMAC, Uruguay, to study diet quality and to provide an understanding of how the rapid defoliation that occurs under rotational grazing affects diet selection. Four levels of forage allowance were evaluated : 5.0 ; 7.5 ; 10.0 and 12.5 kg DM/ 100 kg LW/ day, using 24 yearlings Holstein steers as fixed experimental animals. Forage allowance was adjusted using the Put and Take technique in a rotational grazing system, (7 grazing days and 35 days resting period), using 6 paddocks for each treatment. Diet were collected from all treatments on 10 occasions over 9-month period (winter, spring, summer) using 5 esophageacally fistulated steers. Dietary quality was assessed on the lst, 4th and 7th grazing day determining crude protein (CP), in vitro organic matter digestibility (IVOMD) and neutral detergent fiber (NDF) of extrusa samples in each collection. Biting rate (BR, mean number of bites during 1 min, measured on three times per collection) and bite weight (BW, dry weight of extrusa collected divided by the number of bites taken per collection) were measured concurrently. Diet selection was assessed by difference of forage available quality and extrusa quality on the 1 st grazing day.
Animal Production Science, 2016
ABSTRACT
animal, 2014
Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gest... more Our objective was to evaluate the metabolic, endocrine and hepatic mRNA profiles through the gestation-lactation cycle in purebred (PU: Angus and Hereford) and crossbred (CR: reciprocal F1 crosses) mutliparous beef cows (n = 32), grazing on two herbage allowances of native pastures (2.5 v. 4 kg dry matter/kg BW; LO v. HI) and their associations with cow's productive performance (calf birth weight, milk production and commencement of luteal activity). Cow BW, body condition score (BCS) and blood samples were collected monthly, starting at − 165 days relative to calving (days), and every 2 weeks after calving until +60 days of lactation. Liver biopsies were collected at − 165, − 75, − 45, − 15 ± 10, and +15 and +60 ± 3 days. Metabolic, endocrine and hepatic gene expression profiles, and calf birth weight, milk yield and postpartum commencement of luteal activity were evaluated. Overall, the most pronounced changes in metabolic, endocrine and hepatic gene expression occurred during winter gestation (−165 to − 45 days), when all cows experienced the onset of a negative energy balance (decreased BCS, glucose and insulin, and increased non-esterified fatty acid concentrations, P < 0.008). Concentrations of insulin and IGF-I were greater (P < 0.037) in HI than in LO cows. However, serum IGF-I concentrations and hepatic growth hormone receptor (GHR) and IGF1 mRNA decreased (P < 0.05) during the winter gestation period only in HI cows. Although IGF-I concentrations decreased (P < 0.05) during the early postpartum (−15 v. + 15 days) for all cows, the typical molecular mechanism that control the uncoupling of the growth hormone-IGF1 axis during the transition period of the dairy cattle (reduced hepatic GHR1A and IGF-I mRNA) was not observed in this study. The hepatic mRNA expression of key transcripts involved in gluconeogenesis and fatty-acid oxidation were upregulated (P < 0.05) during winter gestation (from − 165 to − 45, − 15 or +15 days, depending on the cow groups). Particularly, acyl-CoA oxidase-1 mRNA was greater for CR than for PU cows during winter gestation (−75 and − 45 days), and fibroblast growth factor-21 mRNA was downregulated (P < 0.01) only for HI cows during the transition (−15 v. 15 days) and lactation period (+15 to +60 days, P < 0.01). These results, together with the greater BCS, estimated energy intake, increased milk yield and shorter commencement of luteal activity in HI than in LO, and in CR than in PU cows (P < 0.018), would indicate that HI and CR cows were able to adapt more efficiently to changes in nutrient and energy supply through the gestation-lactation cycle.
Livestock Science, 2014
ABSTRACT The objective was to determine effects of prepartum BCS on metabolic/endocrine profiles ... more ABSTRACT The objective was to determine effects of prepartum BCS on metabolic/endocrine profiles and hepatic gene expression and their associations with cow and calf performance in grazing suckled-primiparous beef cows from −49 to 49 days postpartum (DPP). Twenty crossbred cows selected according to expected calving date, were classified at −35 DPP into thin (BCS<4.5) or moderate (BCS≥4.5) BCS groups and blocked by calving date. Blood samples were obtained weekly for metabolite and hormone analyses and liver biopsies were collected at −11, 7, 31, and 49 DPP. Cow BW and BCS were greater in moderate than thin cows throughout the period. Estimated energy intake was greater in moderate than thin cows Moderate BCS cows produced more milk than thin cows at 35 DPP and calves from moderate BCS cows had greater BW and average daily gain than calves from thin cows. Serum leptin tended to be greater while adiponectin was less in moderate than thin BCS cows. Overall serum insulin was less in moderate than thin cows while serum IGF-I during the prepartum was greater in moderate than thin BCS cows. Growth hormone receptor (GHR) mRNA was 2-fold greater at −11 DPP while GHR1A and IGF1 mRNA were 2.5-fold less at 49 DPP in moderate than thin BCS cows. The IGFBP2 mRNA decreased in moderate but increased in thin BCS cows from −11 to 49 DPP. These results were associated with changes in body reserves during prepartum and may indicate that prepartum differences in BCS lost can affect nutrient partitioning towards the mammary gland, and subsequent milk production and calf weight.
Animal Feed Science and Technology, 2012
Effects of daily herbage allowance (DHA) on milk production and composition, body condition score... more Effects of daily herbage allowance (DHA) on milk production and composition, body condition score (BCS) and grazing behavior of primiparous Holstein cows during early lactation were investigated. Cows were blocked by body weight (BW), age and BCS, and randomly assigned within block to one of three grazing treatments (n = 11 cows each) being: high (HA, 30 kg DM/cow/d), medium (MA, 15 kg DM/cow/d) and low (LA, 7.5 kg DM/cow/d) DHA. Cows were grazed in 8 consecutive grazing paddocks (GP) of 7 d of occupation each. The experiment was a completely randomized block design and data were analyzed as repeated measurement in time. Milk production was higher in HA and MA groups than in LA (24.3 and 22.7 vs. 19.2 L, P<0.01 respectively). Milk response to extra DHA was 0.43 L of milk/kg DHA between LA and MA treatments, which dropped to 0.19 L of milk/kg between LA and HA treatments. Cows in the HA treatment had higher BCS than cows in MA and LA treatments (3.18 vs. 3.05 and 3.07; P<0.05). Cows on all treatments mobilized BCS during the first 3 weeks after calving but, while HA cows lost ∼0.5 points of BCS, LA cows lost 1 point. The probability of a cow grazing at any time increased (P<0.01) as the experiment progressed, being 54.5, 61.3, 66.8 and 68.7 min/100 min for GP 3, 5, 7 and 8, respectively. Probability of grazing increased linearly for cows receiving HA (0.39 min/100 min/d) and MA (0.44 min/100 min/d) treatments at higher rate than cows receiving LA (0.22 min/100 min/d) treatment. A linear effect of days in milk (DIM) on bite rate as well as an interaction of DIM by treatment occurred. At DIM = 0, the mean value for bite rate was ∼15 bites/min, and the slope relative to DIM was higher for HA and MA cows (0.54 and 0.69 bites/min/d, respectively) than for LA cows (0.29 bites/min/d). The result of the present experiment evidence the major role of DHA on milk production in primiparous dairy cows during early lactation, being more important at lower levels of DHA. The lack of response on milk production to higher levels of DHA might have been related to the low effective grazing time and bite rate exhibited by early lactation grazing primiparous cows.
Australian Journal of Experimental Agriculture, 2007
Animal Production Science, 2013
The objective of the present experiment was to analyse the effect of body condition score (BCS) a... more The objective of the present experiment was to analyse the effect of body condition score (BCS) at calving, type of suckling restriction and flushing on metabolic and endocrine profiles, and productive and reproductive responses of primiparous beef cows grazing native grassland. Primiparous beef (n = 56) cows in anestrus classified by BCS at calving (low 3.5 and moderate !4; 1-8 visual scale) were assigned randomly to four treatments in a two by two factorial arrangement of type of suckling restriction and flushing. Type of suckling restriction started at 55 AE 10 days postpartum (DPP AE s.e.m.; Day 0 = initiation of the treatment) and consisted of applying nose plates to calves for 12 days (i.e. TS treatment) or 5 days of isolation of the cow-calf pair, followed by applying nose plates to calves for 7 days as calves were reunited with their mothers (i.e. IS treatment). Immediately after the suckling restriction treatments were finished, the breeding season started, and each cow received (flushing group) or not (control group) 2 kg/day (fresh basis) of whole-rice middling for 22 days. The BCS was superior in moderate-BCS cows through the experiment. The type of suckling restriction did not affect any plasma parameter, but insulin-like growth factor I (IGF-I) concentrations increased in all cows during suckling restriction. Cholesterol concentration was affected by flushing · day interaction (P < 0.05), while insulin and IGF-I concentrations were affected by the interaction among BCS at calving, flushing and days (P < 0.03). Flushing increased cholesterol concentration in both BCS groups at calving, while insulin and IGF-I concentrations increased during flushing only in moderate-BCS cows. Suckling restriction, flushing, and BCS at calving did not affect calf weight or milk production. Moderate BCS cows had a shorter postpartum anestrous interval (PPI) (98 vs 123 DPP; P < 0.01). Isolated type of suckling reduced postpartum anestrous interval when compared with TS treatment (97 vs 115 DPP, P < 0.05). Early pregnancy rate was greater in flushed than in control cows (0.8 vs 0.55, P < 0.01) and in moderate-BCS cows than in low-BCS cows (0.84 vs 0.46, P < 0.01). Total pregnancy rate was also greater in flushed and moderate cows and tended to be affected by the interaction between flushing and BCS at calving (P = 0.06; flushed cows: moderate = 1 vs low = 0.5, P < 0.08; and control cows: moderate = 0.8 vs low = 0.4, P < 0.09). These results confirmed the great value of suckling restriction and flushing during post-calving and relevance of BCS at calving as a link between energetic nutrition and metabolic and reproductive processes in primiparous beef cows grazing native grassland.
Animal Production Science, 2015
Research conducted over recent decades to improve understanding of the functional responses among... more Research conducted over recent decades to improve understanding of the functional responses among sward characteristics, intake rate and grazing behaviour has been reviewed. The opportunities to modify grazing pattern by changes in feeding management are discussed and the implications for dairy-farm feeding strategies are highlighted. Progress in the understanding of the functional responses between sward characteristics and intake rate and their main components (bite mass, bite area, bite depth and bite rates) has been substantial. However, progress in understanding the factors that mediate the initiation and the end of individual meals has been poorer and requires further study. Much of the research has been conducted using short-term experiments with a limited number of experimental animals and mostly conducted on mono-specific uniform swards. The physiological state of the animal as well as the maintenance energy associated with grazing strategies have received very little, if any, attention. More integrated (sward, animal, management) and long-term basic research is required to improve feeding practices at the farm level and the design of farms for the new generation of grassland-based dairy-production systems.
América Latina cuenta con aproximadamente el 25% de la población mundial de vacunos (Scherf, 1997... more América Latina cuenta con aproximadamente el 25% de la población mundial de vacunos (Scherf, 1997) y en ella coexisten países con énfasis exportador, Brasil, primer exportador a nivel mundial, Argentina, 4to, Uruguay, 7mo, entre otros (Rearte, 2007) e importadores. Sin embargo, en todos ellos la producción de carne bovina es un rubro importante del sector pecuario y la cría se realiza fundamentalmente en sistemas pastoriles sin subsidios. La región comparte una baja eficiencia reproductiva, manifestada por la baja producción de terneros destetados, y los principales problemas identificados como responsables de esa situación: la avanzada edad a primer parto y el prolongado anestro post-parto de nuestros rodeos u hatos. Uruguay no es la excepción, registros históricos indican que el promedio nacional del porcentaje de destete se ha mantenido en los últimos 20 años en el entorno del 63% con las vacas de primera cría presentando los menores porcentajes de preñez y destete (DI. CO.SE). Las fluctuaciones entre años reflejarían mayoritariamente la influencia del clima sobre la producción de forraje y energía, principal nutriente limitante del proceso de la cría. Por lo que, una de las prioridades del sistema criador uruguayo, como el de la mayoría de los países latinoamericanos, es la mejora del porcentaje de destete con alternativas de bajo costo y fácil aplicación. Cualquier opción para lograr este objetivo debe tener presente que la cría vacuna del Uruguay forma parte del sector exportador, por ende dichas prácticas deben ser compatibles con la producción de carne con denominación de origen y amigables con el medio ambiente.
Livestock Science, 2014
ABSTRACT Visceral tissues impact on the partitioning of metabolizable energy between maintenance ... more ABSTRACT Visceral tissues impact on the partitioning of metabolizable energy between maintenance and production. The aim of this study was to evaluate long-term effects of two herbage allowances of native pastures on mass, composition and expression of mitochondrial respiratory protein encoding genes on gastrointestinal tract (GIT) organs and liver in pure (Angus and Hereford, PU) and crossbred (reciprocal F1, CR) beef cows. Mature beef cows (n=32) were used in a complete randomized block design with a factorial arrangement of herbage allowance (2.5 vs. 4 kg DM/d; LO vs. HI) and cow genotype (PU vs. CR). The experiment was conducted during three years and at the end of the third year, cows were slaughtered at 190±10 d postpartum, and GIT organs and liver were dissected, weighed, and samples collected and immediately frozen. Reticulum-rumen (P=0.02) and total intestine (P=0.02) absolute mass (kg) was greater in HI than LO cows and greater in CR than PU cows, and liver (P<0.01) mass were greater in HI than LO cows. Abomasum protein content was greater (P<0.01), while omasum protein content tended (P=0.10) to be greater for HI-PU than LO-PU cows. The reticulum-rumen and abomasum lipid contents tended to be less (P<0.10) in HI than LO cows. Except for the large intestine and liver, concentration of DNA and protein:DNA ratio did not differ in GIT viscera of different cow groups. The protein:DNA ratio of the large intestine was greater (P=0.03) in HI-CR than LO-CR cows, while the hepatic protein:DNA ratio was less (P=0.04) in HI-CR than LO-CR cows while not differing of HI-PU and LO-PU cows that presented intermediate values. The small intestine expression of NDUFB8 and COX5B mRNA were greater (P<0.05) and NDUFS4 mRNA tended (P=0.06) to be greater in HI than LO cows. The expression of UQCRC1 mRNA was greater (P=0.04) and SDHA mRNA tended to be greater (P=0.08) in CR than PU cows. Hepatic NDUFB8, NDUFS4 and COX5B mRNA was greater (P<0.05) in LO-CR than HI-CR and LO-PU cows being intermediate in HI-PU cows. The CYC1 mRNA was greater (P=0.05) in LO than HI cows. These results suggest that CR cows would have greater plasticity in order to adapt their visceral mass and gene expression to sparse environments.
Journal of Animal Physiology and Animal Nutrition, 2012
ABSTRACT Sixty-four spring-calved primiparous crossbred cows paired by calving date and body cond... more ABSTRACT Sixty-four spring-calved primiparous crossbred cows paired by calving date and body condition score (BCS) at calving were used to study the effect of a short-term increase in the nutritional plane before the mating period on cow and calf performance, changes in metabolic and endocrine parameters and hepatic gene expression. At 48 ± 10 days post-partum (onset of nutritional treatment = day 0), cows were assigned to two treatments during 23 days: control (grazing of native pastures; NP; n = 31) and increased nutritional plane (NP improved with Lotus subbiflorous cv Rincon; IP; n = 33). Cow body weight (BW), BCS and total protein and albumin concentrations increased while urea and non-esterified fatty acids levels decreased from the beginning of the nutritional treatment in both groups, indicating the animal positive energy balance as forage growth and availability of pastures increased during spring. In addition, cow BW and BCS, as well as calf average daily gain and BW, were greater in IP than in NP cows groups. Insulin concentrations were less in IP than in NP (1.37 vs. 2.25 ± 0.26 μU/ml) because insulin increased owing to nutritional treatment only in NP cows. Hepatic insulin receptor mRNA at day 23 tended to be 1.5-fold greater, while insulin growth factor binding protein-3 mRNA expression was 1.7-fold greater in NP than in IP cows. Reproductive responses were not affected by nutritional treatment, but days to initiation of ovarian ciclicity (108 ± 10 days) were positively correlated with insulin concentrations. Grazing of improved NP for 23 days before the mating period did not improve cow reproductive performance but modified metabolic, endocrine and gene expression parameters, in agreement with greater nutrient and energy partitioning towards milk production, reflected in better calf performance.
Animal Production Science, 2013
The objectives of the present experiment were to analyse the reproductive and productive response... more The objectives of the present experiment were to analyse the reproductive and productive responses to sucklingrestriction treatments and flushing in primiparous grazing beef cows. During 3 years, 153 primiparous anoestrus cows were assigned randomly to one of four treatments in a 2 by 2 factorial arrangement of suckling-management treatments and flushing. Suckling-restriction treatments started at 61 AE 10 days postpartum and consisted of applying nose plates to calves for 12 days (i.e. TS treatment) or 5 days of isolation of the calf from the cow followed by applying nose plates to calves for 7 days as calves were reunited with their mothers (i.e. IS treatment). Nutritional treatments (flushing v. control) started at the beginning of the breeding season, immediately after the suckling-restriction treatments were finished (73 AE 10 days postpartum), with cows receiving or not receiving 2 kg/day of whole-rice middling for 22 days. Cow body condition score (BCS) was recorded every 20 days from calving until 120 days postpartum. Duration of postpartum anoestrus (PPA) and probability of cyclicity were estimated by plasma progesterone concentrations analysed in weekly samples. Pregnant cows were determined by ultrasound 42 days after bull introduction (early pregnancy; EP) and 30 days after the end of the breeding season (total pregnancy; TP). BCS at calving and changes in BCS from calving to the day of BCS nadir (DBCS) varied among years depending on forage availability and weather conditions. Increased cow BCS at calving decreased PPA (b = -41 days, P < 0.0001) and, in interaction with DBCS, increased EP (P < 0.008) and TP (P < 0.003). Calf weights at weaning and average daily gain were not affected by suckling-restriction or flushing treatments. Isolated temporary suckling control reduced PPA by 11 days when compared with temporary suckling control (P < 0.004). Flushing increased EP by 40%, which was also affected by BCS at calving and was greater in cows that gained, than in those that maintained or lost BCS. We conclude that flushing was useful in improving early pregnancy rates of primiparous beef cows with 'suboptimal' body condition (lower than 4.5) at calving and grazing native pasture.