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RIA. Revista de investigaciones agropecuarias

On-line version ISSN 1669-2314

RIA. Rev. investig. agropecu. vol.46 no.2 Ciudad Autónoma de Buenos Aires May 2020

 

Artículos

Promotion of Lotus tenuis and calf early weaning as a good management practice for breeding herds in marginal soils of the Flooding Pampa (Argentina)

M. BAILLERES1 

M.P. CAMPESTRE2 

C.J. ANTONELLI3 

G. MELANI4 

A. MENÉNDEZ5 

O.A. RUIZ6  7 

1Instituto Nacional de Tecnología Agropecuaria (INTA), Chacra Experimental Integrada de Chascomús (CEICh). Chascomús, Buenos Aires, Argentina.

2Instituto Tecnológico de Chascomús (INTECh). Universidad Nacional San Martín (UNSAM), Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, (CONICET). Chascomús, Buenos Aires, Argentina.

3Instituto Tecnológico de Chascomús (INTECh). Universidad Nacional San Martín (UNSAM), Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, (CONICET). Chascomús, Buenos Aires, Argentina.

4Instituto Nacional de Tecnología Agropecuaria (INTA), Chacra Experimental Integrada de Chascomús (CEICh). Chascomús, Buenos Aires, Argentina.

5Universidad de Buenos Aires (UBA), Facultad de Ciencias Exactas y Naturales, (FCEN-UBA). CABA, Buenos Aires, Argentina.

6Instituto Tecnológico de Chascomús (INTECh). Universidad Nacional San Martín (UNSAM), Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina, (CONICET). Chascomús, Buenos Aires, Argentina.

7Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Fisiología y Recursos Genéticos Vegetales (IFRGV) (CIAP). Córdoba, Argentina.

Abstract

The promotion of forage legumes in marginal environments for agriculture constitutes a major technological challenge for livestock farming. The legume Lotus tenuis .Waldst. & Kit.) is a good example of beneficial naturalization in the Salado River Basin, that is, in the largest area dedicated to bovine farming in the country. The aim of this study was to evaluate the promotion of L. tenuis in marginal areas as a valuable alternative for early weaning systems in livestock production. Two treatments were tested during three study periods. To evaluate the efficiency of the proposed system, average daily weight gain (DWG) and weight gain (WG) of conventional weaning (CW) and early weaning (EW) calves were determined and compared. EW calves grazing on L. tenuis gained more weight than CW calves during Study period 1 (P = 0.028), but no differences were observed between treatments during Study periods 2 and 3 (P ˃ 0.05). Body Condition Score (BCS) for dams in both treatments was evaluated. For all three study periods, BCS improvement was higher in cows from the EW treatment than in Lactating cows (LC) from the CW treatment. Thus, EW improved cow BCS and did not generate weight reductions in calves thanks to the Lotus-based diet. In conclusion, L. tenuis promotion in the summer season resulted higher yields in marginal areas than semi–natural pastures. It also provided an acceptable nutritional value to properly fed a considerable amount of calves on a small surface area, and enabled a better recovery of the dams in terms of body condition. The obtained results support the design of an easy-to-use strategy that facilitates adoption by producers.

Keywords biomass; pastures; legumes; livestock

Resumen

La promoción de leguminosas forrajeras en ambientes marginales para la agricultura constituye un importante desafío tecnológico para la ganadería. Lotus tenuis (Waldst. & Kit.) es un buen ejemplo de naturalización beneficiosa en la Cuenca del Río Salado, es decir, en una de las más importantes regiones dedicada a la cría de bovinos en el país. El objetivo de este estudio fue evaluar la promoción de L. tenuis como una alternativa valiosa para los sistemas de destete temprano en la producción ganadera. Se probaron dos tratamientos durante tres períodos de estudio. Para evaluar los beneficios del sistema propuesto, se determinó y comparó la ganancia de peso diario promedio y la ganancia del peso de terneros según se utilizaran procesos al pie de la vaca o con un destete temprano. Los terneros provenientes de un destete temprano que pastaban en promociones de L. tenuis ganaron más peso que los terneros provenientes de un destete convencional durante el período de estudio 1 (P = 0.028), pero no se observó diferencia entre los tratamientos durante los períodos de estudio 2 y 3 (P ˃ 0.05). Se evaluó la puntuación de condición corporal para las madres en ambos tratamientos. Para los tres períodos de estudio la mejora de esta condición fue mayor en las vacas del tratamiento de destete temprano que en las vacas lactantes del tratamiento convencional. Por lo tanto, el destete temprano mejoró la condición corporal de la vaca, sin generar reducciones de peso en los terneros gracias a la dieta basada en L. tenuis. En conclusión, la promoción de esta leguminosa en la temporada de verano proporcionó mayores rendimientos en áreas marginales para la agricultura que las pasturas seminaturales. Asimismo, proporcionó una dieta con un valor nutricional aceptable para la alimentación adecuada de una cantidad considerable de terneros en una superficie pequeña, permitiendo al mismo tiempo, una mejor recuperación de las madres en términos de condición corporal. Los resultados obtenidos respaldan el diseño de una estrategia sencilla que facilita la adopción por parte de los productores.

Palabras clave biomasa forrajera; pasturas; leguminosas; ganado vacuno.

MATERIALS AND METHODS

Site and Pasture description

The study was conducted at the Chacra Experimental Integrada de Chascomús (CEICh–Ministerio de Agroindustrias de la Provincia de Buenos Aires–Instituto Nacional de Tecnología Agropecuaria, Argentina, 35º45’27”S, 58°3’18”W), which is located in the Flooding Pampa region, during the periods 2010–2011, 2011–2012 and 2012–2013 (Study periods 1, 2 and 3, respectively). This region has a temperate sub–humid climate with mean temperatures averaging 8.5 °C in winter and 21.5 °C in summer, and annual rainfall 850–1050 mm. Short floods of 5–7 cm depth occur at the beginning of almost every spring. Nonetheless, severe droughts may occur in early summer. Soils in the experimental area are Natraquoll type, characterized by an A1 horizon with 3.5% of organic matter and 0.22 mg kg–1 of extractable Fe, and by a natric B2t horizon at a depth of 17 cm, with 53.3% clay content (Lavado and Taboada, 1988). Plant communities consist mainly of grasses and Compositae species. Native legumes are largely absent and semi–natural pastures are dominated by Festuca arundinacea, Thinopyrum ponticum, Cynodon dactylon, L. tenuis, and Sporobolus indicus.

Promoted L. tenuis pasture

Glyphosate (N–(phosphonomethyl) glycine; 3.5 l ha–1) was applied on a 2 hectares surface area, followed by two applications of 2,4 DB(4–(2,4–dichlorophenoxy) butyric acid, 1 l ha–1) and a single dose of Quizalofop–p–ethyl (Ethyl(R) –2– [4– (6– chloro–2–quinoxalyloxy) phenoxy] propionate; 1.2 l ha–1), in six or seven annual cycles from June to August. After 4 or 5 years of herbicide application, plant species composition in promoted paddocks shifted, and L. tenuis became the dominant species (Nieva et al., 2016; 2018; 2019; Druille et al., 2017).

Weaning treatments

For comparative purposes, both groups of animals were simultaneously incorporated to the experimental lots: a) use of herbicides to increase the presence and persistence of L. tenuis and b) without the use of herbicides (semi-natural pasture). Regarding the load, 2 ha were assigned to the EW calves in the Lotus promoted paddocks. The dams from EW animal lots and cows-calf pairs from CW management (one animal per ha), grazed in the semi-natural pasture during 4-5 days, in parcels with availability of 1500 to 2000 kg DM/ha and were removed from parcels with remnants forage between 800 and 1200 kg DM/ha. This animal management protocol was optimized years previous to the EW and CW evaluation.

Two treatments were proposed: (1) CW: cow–calf pairs grazing on semi–natural pasture (LC n = 20; calves n = 20), and (2) EW: calves weaned at the age of 4–5 months, grazing on promoted L. tenuis paddocks (calves n = 20) and dams grazing on semi–natural pasture (n = 20).

Measurements were performed in the three growth periods mentioned above: Study period 1, Study period 2, and Study period 3 from February to March according to forage availability. All animals used in this research reached maturity and were included in the CEICh usual livestock productivity cycle.

Animal measurement

In each study period and treatment, Aberdeen Angus calves and dams were used to evaluate the Weight Gain (WG), average Daily Weight Gain (DWG), and Body Condition Score (BCS). At the beginning of each study period and treatment, calf weight averaged 160 kg (initial weight). All calves from both treatments were reweighed (final weight) 25 days after the first weight register during the Study period 1, 34 days later during the Study period 2 and 60 days later during Study period 3. This difference in the test time of each period was due to climatic or technical conditions. DWG was then calculated as [final weight–initial weight]/X days of the study period.

Initial BCS was determined for all LC and EW dams at the beginning of treatments. BCS refers to the relative amount of subcutaneous body fat or energy reserve in the cow. It was estimated by visual appraisal and scores were assigned from 1 to 5, where 1 = a very thin cow and 5 = an excessively fat one. At the end of each experiment, BCS determination was repeated on the same cows. BCS change in the period was calculated as final BCS–initial BCS.

Pasture measurement

Plant biomass was harvested from ten 0.25 m2 quadrats. Plant samples were collected six times during the growing season (October to March) for all three study periods, by clipping approximately 1 cm above the soil surface. Samples were dried at 70 °C to constant weight, and dry biomass was calculated per hectare.

For forage quality determinations, L. tenuis plants were clipped in December, January, and February, with similar results. The biomass quantity and quality required for acceptable calf performance were evaluated by Dry Matter (DM); Digestible Dry Matter (DDM) and Metabolisable Energy (ME) –by Tilley and Terry method-; Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) –by Van Soest et al. (1991) method-and Crude Protein (CP) -by Kjeldahl method- of promoted L. tenuis plants. All these parameters were evaluated following routinely protocols and processes standardized in the Animal Nutrition and Forage Evaluation Laboratory located in INTA Balcarce Experimental Station (Buenos Aires, Argentina).

Statistical analysis

Since the weaning treatment was applied directly to the cow and the calf, they were both considered as the experimental unit for all analyses. The experimental design was completely randomized and each study period represented an independent experiment with a different stock of animals. Plant biomass, WG, and DWG for EW and UW calves, and cow BCS were analyzed by t–Tests (P ≤ 0.05) for mean separations for each period using the INFOSTAT statistical software package (InfoStat version 2010. Grupo InfoStat, FCA, Universidad Nacional de Córdoba, Argentina, http://www.infostat.com.ar). P–values ≤ 0.05 were considered statistically significant and P ˃ 0.05 but ≤ 0.10 were considered trends.

RESULTS

Biomass accumulation and nutritional values

For all three study periods, L. tenuis biomass accumulation was consistently higher than the semi–natural pasture biomass, with an average value per growth period of 4525 kg ha–1 DM and 2824 kg ha–1 DM, respectively (Figure not shown). Moreover, as shown in figure 1.A, during the summer season (January–February–March), biomass was lower in the semi–natural pasture, while L. tenuis biomass was slightly higher, and even more so compared to semi–natural pasture in the grazing months of EW calves (February–March). Figure 1.B shows the typical coverage that each pasture reached in the summer season.

Figure 1(A) Average value of forage dry mass accumulation (kg ha-1 DM) during Spring (Spr) and Summer (Summ) seasons during three years of experimental evaluation (period 1, 2 and 3), in promoted L. tenuis (Lotus), grey bars, and semi–natural pasture (SNP), violet bars. Bars (mean ± SD; n = 3) with asterisks represent significant differences between forage offer. (B) Typical observation of marginal soils after 4 to 5 yr. of L. tenuis promotion and semi-natural vegetation in marginal areas of the Salado River Basin. 

In addition to biomass accumulation, table 1 shows the values of forage nutritional quality in promoted L. tenuis plants during the summer season.

Table 1Forage nutritional quality of promoted L. tenuis evaluated as dry matter (DM, g kg–1), digestible dry matter (DDM, g kg–1 DM), metabolizable energy (ME, Mcal kg–1 DM), neutral detergent fiber (NDF, g kg–1 DM), acid detergent fiber (ADF, g kg–1 DM), and crude protein (CP, g kg–1 DM).† Values are averages from samples taken at three different times, from December to February. ‡ Standard deviation. 

Influence of weaning treatment and promoted L. tenuis pasture on calf performance

Calf DWG was influenced by weaning treatment (table 2 A). DWG was higher during Study period 2 (2011–2012) (DWG = 0.65 kg day–1P ≤ 0.05) and presented a trend in favor of EW and grazing on promoted L. tenuis during Study period 1 (2010–2011) (DWG = 1.21 kg day-1 P≤ 0.10). However, during Study Period 3 (2012–2013), there was a difference in favor of UW calves grazing on semi–natural pastures (DWG = 0.70 kg day-1 P ≤ 0.05). Regarding WG, it is important to note that all calves in both treatments weighed approximately the same (~160 kg) at the beginning of each study period (table 2 B). No WG differences were found between weaning treatments during Study period 2 and 3. However, there were WG differences during period 1 in favor of EW and grazing on promoted L. tenuis during 25 days.

Table 2Influence of weaning treatments and grazing source on calf performance expressed as (A) Daily weight gain (kg) and (B) Weight (kg).† Conventional–weaned treatment consisted of cow–calf pairs (n = 20 calves) grazing on semi–natural pastures while early–weaned treatment consisted of 4–5–month–old calves (n = 20) grazing on 2 hectares of promoted L. tenuis paddocks. ‡ Study period 1: (2010–2011) lasted 25 days, 2: (2011–2012) lasted 34 days and 3: (2012–2013) lasted 60 days. §Standard deviation. 

Influence of weaning treatment on cow performance

At the end of each assay, cow BCS (table 3) improved more in EW cows than in LC for Study Periods 1 and 3 (P< 0.05) but no differences were recorded for Study Period 2. It should be noted that in Study Period 2 EW cows started with a lower BCS (2.625) than LC (2.917). However, by the end of the 34–day treatment, BCS gain was 0.275 for EW cows but –0.084 for LC cows. At the same time, in all the three studied periods, the period change value was greater for the EW cows compared to the period change value for the CW cows.

Table 3Influence of weaning treatments on cow performance expressed as Body Condition Score (BCS).† Study period 1: (2010–2011) 25 days, 2: (2011–2012) 34 days and 3: (2012–2013) 60 days. ‡INITIAL BCS was measured in all cows at the beginning of both treatments (Conventional and Early weaning). § FINAL BCS was measured in all cows at the end of each Study period time. ¶ Standard deviation. 

DISCUSSION

The grasslands of the Flooding Pampa are subject to the combined effects of grazing, floods, and droughts. Thus, a sustainable solution is needed for forage production enhancement in marginal environments. L. tenuis promotion is an appealing alternative for cattle production in constrained environments in this region. Our results show that L. tenuis promotion produced higher forage yields than the supply provided by the semi–natural pasture under these soil conditions (figure 1A).

L. tenuis not only contributes with quantity but also nutritional quality (table 1). L. tenuis values are comparable to those of other two Leguminosae: L. corniculatus (L). and T. repens (L). (Peiretti et al., 2016) with global commercial importance (Phelan et al., 2015) rich in high-quality protein content and highly digestible (Kaplan et al., 2009; Graves et al., 2012).

This study shows a clear improvement in BCS for EW cows. Similar results have been reported in other weaning studies conducted on pasture (Merrill et al., 2008; Martins et al., 2012; Johnson et al., 2015). The lower BCS of LC compared to EW cows may be explained mainly by the continued demand for milk by UW calves (Johnson et al., 2015). Therefore, since UW calves are frequently maintained as cow–calf pair for approximately a month and a half longer than the period analyzed in this study, further BCS losses in LC would be expected. As reported by Whittier (1995), the long–term effect of lactation may delay pregnancy, so earlier weaning would improve BCS and increase pregnancy rate (Thrift and Thrift, 2004).

During Study Period 1, DWG did not differ between treatments and was higher than in Study Periods 2 and 3. In turn, differences were detected between treatments in the latter two periods, with higher DWG in EW than UW calves for Study Period 2, while the opposite occurred for Study Period 3. Such discrepancy could be given by the interval between days that the calves were found grazing Lotus in each study period. Hence, it would not be advisable to keep the calves grazing promoted L. tenuis for more than 34 days, probably due to the trampling effect generated by the calves on the pasture, unless the stocking density per hectare will be reduced. However, to draw better conclusions further research analyzing additional sources of variation is required.

Weatherly (2008) reports that EW calves aged 3–6 months require 160 g kg–1 DM of CP for a 0.70 kg day–1 growth rate. Former information and our results showing CP values of 203.3 g kg–1 DM and DM of 245.3 g kg–1 for promoted L. tenuis suggest that it is highly suitable as forage. In our study, this is reflected by the WG observed for animals grown on pastures promoted with predominance of L. tenuis during 25 days. The promotion of small areas of L. tenuis thus seems to be an important strategy enabling higher yields, taking into account that our results suggest that only 1 hectare is required to fully feed ten 4–5–month–old calves for a short period (table 2).

It is important to highlight that the promotion of L. tenuis would be one more link in the forage chain in a cow breeding enterprise, which would determine an advantage in a given period, which maybe be accompanied by other resources such as natural grassland or ryegrass promotions.

CONCLUSIONS

The technology of L. tenuis promotion that was designed and assayed by the Chacra Experimental Integrada de Chascomús produced higher yields than those provided by semi–natural pastures. Also, L. tenuis has an acceptable nutritional value for adequately feeding a considerable number of calves on a small surface. L. tenuis has a high capacity for natural reseeding and can withstand the water deficit that often occurs from late spring through summer (Vignolio et al., 2011; Escaray et al., 2012). Forage supply is especially important in summer when breeding herd requirements are usually at their maximum. Ideally, this demand should be met by pasture quantity and quality and/or supplementary feed. Another point to consider is that in grasses and legumes the digestion rate is influenced by the increase in the lignin content at the beginning of the flowering period (Mahyuddin, 2008). L. tenuis, however, continues vegetating even after the flowering period, with a wide overlap between vegetative and reproductive growth, as has been previously described for indeterminate growth species (Vignolio et al., 2016). Thus, EW of calves grazing on this forage is a useful management practice that reduces grazing pressure on semi–natural pastures, decreasing cow nutrient requirements. BCS improvement in EW cows could shorten the postpartum interval and improve pregnancy rate. This management practice can be potentially transferred to producers. Likewise, its adoption will allow us to increase the accuracy of the obtained results and its adaptation to other environments. It is also important to highlight the production of higher–quality meat, identifiable by its levels of unsaturated fatty acids, from animals fed on promoted L. tenuis compared to meat from animals fed in intensive fattening systems based on grains and balanced pelleted foods (Acosta et al., 2016). Therefore, we consider that this cow management practice could effectively improve the productivity in Argentina’s most important livestock breeding region.

Acknowledgments

This work was financed by the following grants: PICT of Agencia Nacional de Promoción Científica y Tecnológica (ANPCYT, Argentina); Universidad Nacional de San Martin (UNSAM, Argentina) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET, Argentina). We also appreciate the excellent technical assistance of the CEICh professional farm staff.

REFERENCES

ACOSTA, A.; ROSSI, J.L.; ACOSTA, G.; SCHOR, A.; GOLLUSCIO, R. 2016. Productive strategy of steers in a marginal area of the Pampean Region.vi Workshop of Lotus spp. Chascomús, Buenos Aires (Argentina). [ Links ]

ACUÑA, H.P. 1998. Varietal comparison of three species of genus Lotus .L. corniculatus L., L. uliginosus Cav. and L. tenuis Wald et Kit.) in soils with aptitude for cropping rice. Agric Tec Chile 58: 7-14. [ Links ]

Antonelli, C.J.; Calzadilla, P.I.; Escaray, F.J.; Babuin, M.F.; Campestre, M.P.; Rocco, R.; BORDENAVE, C.D.; PEREA GARCÍA, A.; NIEVA, A.S.; LLAMES, M.E.; MAGUIRE, V.; MELANI, g.; SARENA, D., BAILLERES, m.; CARRASCO, P.; PAOLOCCI, F.; GARRIZ, A.; MENÉNDEZ, A.; RUIZ 2016. Lotus spp: Biotechnological strategies to improve the bioeconomy of lowlands in te Salado River Basin (Argentina). AGROFOR International Journal, 1. [ Links ]

Antonelli, C.J.; Calzadilla, P.I.; Vilas, J.M.; Campestre, M.P.; Escaray, F.J.; Ruiz, O.A. 2019. Physiological and anatomical traits associated with tolerance to long-term partial submergence stress in the Lotus genus: responses of forage species, a model and an interspecific hybrid. J. Agron Crop Sci, 205(1), 65-76. [ Links ]

ARTHINGTON, J.D.; SPEARS, J.W.; MILLER, D.C. 2005. The effect of early weaning on feedlot performance and measures of stress in beef calves. J Anim Sci 83: 933-939. [ Links ]

BETANCOURT–LÓPEZ, L.; PAREJA–MEJÍA, R.I.; CONDE–PULGARÍN, A.; CASTELLANOS, A.F.; MORENO–MARTÍNEZ, D. 2012. Manejo nutricional de terneros cebú comercial sometidos a amamantamiento restringido y destete precoz en el piedemonte de Casanare. Rev Cie Anim 5: 21-30. [ Links ]

BLUMENTHAL, M.J.; MCGRAW, R.L. 1999. Lotus adaptation, use and management. In: BEUSELINCK, P.R. (Ed.). Trefoil: The Science and Technology of Lotus, CSSA. 28: 97-119. [ Links ]

CASSIDA, K.A.; GRIFFIN, T.S.; RODRIGUEZ, J.; PATCHING, S.C.; HESTERMAN, O.B.; RUST, S.R. 2000. Protein degradability and forage quality in maturing alfalfa red clover, and birdsfoot trefoil. Crop Sci 40: 209-215. [ Links ]

CASTELLS, L.; BACH, A.; ARIS, A.; TERRÉ, M. 2013. Effects of forage provision to young calves on rumen fermentation and development of the gastrointestinal tract. J DairySci96: 5226-5236. [ Links ]

CLUA, A.A.; GIMENEZ, D.O.; FERNANDEZ, L.V. 1997. Increase in forage yield in narrow leaf birdsfoot trefoil (Lotus tenuis Waldst & Kit ex Willd) in a permanent pasture with foliar applied gibberellic acid (GA3), and phosphorus. Plantgrowthregul 21: 223-228. [ Links ]

COLABELLI, M.; MIÑON, D. 1994. Rendimiento y cambios botánicos de pasturas de Lotus tenuis puro y en mezcla bajo régimen de corte. AgriculturaTécnica, Chile 54: 39-45. [ Links ]

CORRIHER, A.; HILL, G.M.; ANDRAE, J.G.; FROETSCHEL, M.A.; MULLINIKS, B.G. 2014. Cow and calf performance on Coastal or Tifton 85 Bermudagrass pastures with aeschynomene creep-grazing paddocks. J Anim Sci 85: 2762-2771. [ Links ]

DRUILLE, M.; ACOSTA, A.; ACOSTA, G.; ROSSI, J.; GOLLUSCIO, R.A.; BAILLERES, M. 2017. Response of beneficial soil fungi associated with Lotus tenuis to the application of glyphosate. RIA 43: 3. [ Links ]

ENRÍQUEZ, D.; HÖTZEL, M.; UNGERFELD, R. 2011. Minimising the stress of weaning of beef calves: a review. Acta Vet Scand 53: 28. [ Links ]

Escaray, F.J.; Menendez, A.B.; Gárriz, A.; Pieckenstain, F.L.; Estrella, M.J.; Castagno, L.N.; Carrasco, P.; San juan PINILLA, j.; Ruiz, O.A. 2012. Ecological and agronomic importance of the plant genus Lotus. Its application in grassland sustainability and the amelioration of constrained and contaminated soils. Plant Science, 182, 121-133. [ Links ]

Escaray, F.J.; Passeri, V.; Babuin, F.M.; Marco, F.; Carrasco, P.; Damiani, F., Pieckenstain, F.L.; Paolocci, F.; Ruiz, O.A. 2014. Lotus tenuis x L. corniculatus interspecific hybridization as a means to breed bloat-safe pastures and gain insight into the genetic control of proanthocyanidin biosynthesis in legumes. BMC plant biology, 14(1), 40. [ Links ]

GRAVES, M.E.; MCLEAN, N.; JONES, G.; MARTIN, R.C. 2012. Pasture and sheep performance response to sod-seeding red clover (Trifoliunpretense L.) or white clover (Trifolium repens L.) into naturalized pastures in eastern Canada. Anim. Feed Sci. Technol. 177: 7-14. [ Links ]

HIDALGO, L.G.; CAUHÉPÉ, M.A. 2009. Argentine rangeland quality influences reproduction of yearling pregnant heifers? Grassl Sci 55: 74–78. [ Links ]

JOHNSON, P.S.; OLSON, K.C.;GATES, R.N.; PATTERSON, H.H.; HUBERT, M.; LANDBLOM, D.; KINCHELOE, J.J.; RICHTER, H.A.; GROVE, A. V. 2015. Early weaning reduces rangeland herbage disappearance. Crop, Forage and Turfgrass Manage. doi:10.2134/cftm2014.0090. [ Links ]

KAPLAN, M; ATALAY, A. I; MEDJEKAL, S. 2009.Potential nutritive value of wild birdsfoot trefoil (Lotus corniculatus) plants grown in different sites. Livest Res Rural Dev 21: 99. [ Links ]

LASTER, D.B.; GLIMP, H.A.; GREGORY, K.E. 1973.Effects of early weaning on postpartum reproduction of cows. J. Anim. Sci. 36:734. [ Links ]

LAVADO, R.S.; TABOADA, M.A. 1988. Water, salts and sodium dynamics in a Natraquoll in Argentina. Catena 15: 577-594. [ Links ]

LUSBY, K.S.; WETTEMANN, R.P.; TURMAN, E.J. 1981. Effects of early weaning calves from first-calf heifers on calf and heifer performance. J. AnimSci 53: 1193-1197. [ Links ]

MAHYUDDIN, P. 2008. Relationship between Chemical Component and In Vitro Digestibility of Tropical Grasses. Hayati J Biosci 15: 85-89. [ Links ]

MARTINS, P.G.M.A.; ARTHINGTON, J.D.; COOKE, R.F.; LAMB, C.G.; ARAÚJO, D.B.; TORRES, C.A.A.; GUIMARĀES, J.D.; MANCIO, A.B.. 2012. Evaluation of beef cow and calf separation systems to improve reproductive performance of first-calf cows. LivestSci 150: 74-79. [ Links ]

MERRILL, M.L.; BOHNERT, D.W.; GANSKOPP, D.C.; JOHNSON, D.D; FALCK, S.J. 2008. Effects of early weaning on cow performance, grazing behavior, and winter feed costs in the Intermountain West. Prof. Anim. Sci. 24: 29-34. [ Links ]

MINSON, D.J. 1990. Forage in Ruminant Nutrition. Academic Press, San Diego 483. [ Links ]

MIÑON, D.; SEVILLA, H.; MONTES, L.; FERNÁNDEZ, O.N. 1990. Lotus tenuis: leguminosa forrajera para la Pampa Deprimida. EEA Balcarce, INTA, Argentina. Boletín Técnico. 98: 15. [ Links ]

MONTES, L.1988. Lotus tenuis, Revista Argentina de Producción Animal 8: 367-376. [ Links ]

MOORE, C.P.; CAMPOS DA ROCHA, C.1983. Reproductive performance of Gyr cows: the effect of weaning age of calves and postpartum energy intake. J. Anim. Sci. 57: 807-814. [ Links ]

MULLINIKS, J.T.; WATERMAN, R.C.; GEARY, T.W. 2013. Economics of early weaning in northern great plains beef cattle production system. Agric. Sci. 4: 219-233. [ Links ]

Nieva, A.S.; Bailleres, M.A.; Corriale, M.J.; Llames, M.E.; Menéndez, A.B.; Ruiz, O.A. 2016. Herbicide-mediated promotion of Lotus tenuis (Waldst. & Kit. ex Wild.) did not influence soil bacterial communities, in soils of the Flooding Pampa, Argentina. Applied soil ecology, 98, 83-91. [ Links ]

Nieva, A.S.; Bailleres, M.A.; Llames, M.E.; Taboada, M.A.; Ruiz, O.A.; Menéndez, A. 2018. Promotion of Lotus tenuis in the Flooding Pampa (Argentina) increases the soil fungal diversity. Fungal Ecology, 33, 80-91. [ Links ]

Nieva, A.S.; Vilas, J.M.; Gárriz, A.; Maiale, S.J.; Menéndez, A.B.; Erban, A.; Kopka, J.; Ruiz, O.A. 2019. The fungal endophyte Fusarium solani provokes differential effects on the fitness of two Lotus species. Plant Physiology and Biochemistry, 144, 100-109. [ Links ]

ODHIAMBO, J.F.; RHINEHART, J.D.; HELMONDOLLAR, R.; PRITCHARD, J.Y.; OSBONE, P.I.; FELTON, E.E.; DAILEY, R.A. 2009. Effect of weaning regimen on energy profiles and reproductive performance of beef cows. J. Anim. Sci. 87: 2428-2436. [ Links ]

PATE, F.M.; CROCKETT, J.R.; PHILLIPS, J.D.1985. Effect of calf weaning age and cow supplementation on cow productivity. J. Anim. Sci. 61: 343-348. [ Links ]

PEIRETTI, P.G.; GAI, F.; ALONZI, S.; TASSONE, S. 2016. Nutritive value and fatty acid profile of birdsfoot trefoil (Lotus corniculatus) and white clover (Trifoliumrepens) in Alpine pastures. Livest Res Rural Dev 28: 218. [ Links ]

PHELAN, P.; MOLONEY, A.P.; MCGEOUGH, E.J.; HUMPHREYS, J.; BERTILSSON, J.; O´RIORDAN, E.G.; O´KIELY, P.. 2015. Forage legumes for grazing and conserving in ruminant production systems. Crit. Rev. Plant. Sci. 34: 281-326. [ Links ]

PORDOMINGO, A.J. 2002. Early weaning and length of supplementation effects on beef calves. J. Range Manage 55: 327-335. [ Links ]

TERRÉ, M.; PEDRALS, E.; DALMAU, A.; BACH, A. 2013. What do preweaned and weaned calves need in the diet: A high fiber content or a forage source? J. Dairy Sci. 96: 5217-5225. [ Links ]

THRIFT, F.A.; THRIFT, T.A. 2004. Review: Ramifications of weaning spring and fall born calves early or late relative to weaning at conventional ages. Prof. Anim. Sci. 20: 490-502. [ Links ]

TILLEY, J.M.; TERRY, R.A.1963. A two‐stage technique for the in vitro digestion of forage crops. Grass forage sci. 18: 104-111. [ Links ]

TYLER, R. 2012. Weaning management of beef calves - practical guidelines for northern Australian beef producers. Meat and Livestock Australia Ltd, North Sydney, NSW, Australia. [ Links ]

TYLER, R.; ENGLISH, B.; SULLIVAN, M.; JACKSON, D.; MATTHEWS, R.; HOLMES, B.; MACDONALD, N.; OXLEY, T.; LEIGO, S.;SMITH, P. 2012. Weaner management in northern beef herds. Meat and Livestock Australia Ltd, North Sydney, NSW, Australia. [ Links ]

VAN SOEST, P.J.; ROBERTSON, J.B.; LEWIS, B.A. 1991. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. J. Dairy Sci. 74: 3583-3597. [ Links ]

VENDRAMINI, J.M.B.; SOLLENBERGER, L.E.; DUBEUX, J.C.B.; INTERRANTE, S.M.; STEWART, R.L.; ARTHINGTON, J.D. 2006. Concentrate supplementation effects on forage characteristics and performance of early–weaned calves grazing rye–ryegrass pastures. Crop Sci 46: 1595-1600. [ Links ]

VIGNOLIO, O.R.; CAMBARERI, G.S.; MACEIRA, N.O. 2011. Seed production of Lotus tenuis (Fabaceae), a forage legume: effects of row spacing, seeding date, and plant defoliation. Crop Pasture Sci 61: 1027-1035. [ Links ]

VIGNOLIO, O.R.; CAMBARERI, G.S.; PETIGROSSO, L.R.; MURILLO, N.; MACEIRA, N.O. 2016. Reproductive development of Lotus tenuis (Fabaceae) crop defoliated at different times and intensities. Am J Plant Sci 7: 1180. [ Links ]

WARNER, J.M.; JENKINS, K.H.; RASBY, R.J.; LUEBBE, M.K.; ERICKSON, G.E.; KLOPFENSTEIN, T.J. 2015. The effect of calf age at weaning on cow and calf performance and feed utilization by cow–calf pairs. Prof Anim Sci 31: 455-461. [ Links ]

WATERMAN, R.C.; GEARY, T.W.; PATERSON, J.A.; LIPSEY, R.J. 2012. Early weaning in Northern Great Plains beef cattle production systems: i. Performance and reproductive response in range beef cows. Livest Sci 148: 26-35. [ Links ]

WEATHERLY, E. 2008. Early Weaning of Beef Calves. AG1282 ISSN 1329-8062. (Available at: http://agriculture.vic.gov.au/agriculture/livestock/beef/handling-and-management/early-weaning-of-beef-calves/ verified: September 08th 2017). [ Links ]

WHITTIER, J.C. 1995. Time of weaning and cow condition. In Range Beef Cow Symposium. 182. [ Links ]