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Made available in DSpace on 2021-06-25T10:46:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-24 Fundação Agrisus Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) In the context of sustainable tropical agriculture, an innovative corn (Zea mays L.) to silage-grass-legume intercropping system can promotes plant diversity, improves agronomic performance and land-use efficiency, and increases the yield of oversown black oat (Avena strigosa Schreb) and soybean [Glycine max (L.) Merr.] to silage in succession. Thus, during three growing seasons on a Typic Haplorthox in Botucatu, São Paulo State, Brazil, four treatments of a corn to silage production system were implemented in summer/autumn with black oat oversown in winter/spring: (1) corn intercropped with palisade grass (Urochloa brizantha “Marandu”) and black oat overseeded in lines; (2) corn intercropped with palisade grass and black oat overseeded in a broadcast system with superficial incorporation; (3) corn intercropped with palisade grass + pigeon pea [Cajanus cajan (L.) Millsp.] and black oat overseeded in lines; and (4) corn intercropped with palisade grass + pigeon pea and black oat overseeded in a broadcast system with superficial incorporation. During winter/spring, the black oat pastures were grazed by lambs, but results on forage allowance and nutritive value for animal grazing and on animal performance are not reported in the present manuscript. In the fourth growing season, the effect of soybean to silage intercropped with guinea grass (Panicum maximum “Aruana”), with only a residual effect of the four production systems from the previous three growing seasons, was evaluated. Despite greater interspecific competition of palisade grass and pigeon pea intercropped with corn, this more complex system produced better results. Thus, when analyzing this system as a whole, the triple intercrop (corn + pigeon pea + palisade grass) combined with oversown black oat in lines was the most effective option for silage production and for the improvement of other elements of system productivity, such higher surface mulch quantity, leaf nutrient concentrations, and yield of soybean to silage intercropped with guinea grass. This intercrop also generated better nutrient cycling because an increased quantity of nutrients was retained in standing plant residue and surface mulch, which resulted in better land- and nutrient-use efficiency, with an emphasis on nitrogen and potassium. Department of Animal Nutrition and Breeding School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Department of Crop Science College of Agricultural Science São Paulo State University (UNESP) Department of Soil Science College of Engineering São Paulo State University (UNESP) Department of Biostatistics Plant Biology Parasitology and Zoology Institute of Biosciences São Paulo State University (UNESP) United States Department of Agriculture (USDA) Agricultural Research Service (ARS) Department of Animal Nutrition and Breeding School of Veterinary Medicine and Animal Science São Paulo State University (UNESP) Department of Crop Science College of Agricultural Science São Paulo State University (UNESP) Department of Soil Science College of Engineering São Paulo State University (UNESP) Department of Biostatistics Plant Biology Parasitology and Zoology Institute of Biosciences São Paulo State University (UNESP) Fundação Agrisus: 1378/14 Fundação Agrisus: 1387/14 FAPESP: 2013/13702-3 FAPESP: 2013/23853-9 FAPESP: 2014/12950-6 FAPESP: 2014/14935-4 FAPESP: 2014/21772-4 FAPESP: 2015/25413-1 FAPESP: 2015/25718-7 FAPESP: 2017/05044-7 CNPq: 458225/2014-2

Made available in DSpace on 2018-12-11T17:37:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-01 Fundação Agrisus Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Lamb performance was evaluated in four integrated crop-livestock (ICL) systems. The ICL areas were previously planted with maize and marandu palisade grass in December 2013. ICL systems 1 and 2 were also seeded with pigeon pea. After harvesting in April 2014, black oats were sown in rows (ICL 1 and 3) or by broadcast seeding (ICL 2 and 4). Each ICL area was divided into 12 paddocks of 225 m2 to be grazed by young sheep from July 23 to September 30, 2014. To determine if the pasture remained contaminated by free-living stages of sheep gastrointestinal nematodes (GIN) after approximately ten months without animals in the area, 12 worm-free “tracer” lambs (n = 3/ ICL system) grazed each ICL pasture for 14 consecutive days in July 2015 and were later housed in pens, where they remained for another 14 days. The tracer lambs acquired no worm infections, demonstrating that the area was cleared after 300 days without animals. To evaluate GIN infection and uncastrated male lamb performance, we used 60 (n = 15/ system) Poll Dorset x Corriedale (crossbred) sheep with mean body weights of 24.4 ± 3.4 kg from July to September 2015 and 48 (n = 12/ system) Texel x Corriedale sheep with body weights of 26.4 ± 3.5 kg from June to September 2016. Lambs were allocated to the following groups: Group 1 rotated on the 12 ICL1 paddocks; Group 2 rotated on the 12 ICL2 paddocks; Group 3 rotated on the 12 ICL3 paddocks; and Group 4 rotated on the 12 ICL4 paddocks. Each paddock was grazed by sheep twice for three days, with a 33-day interval between grazing. At the end of the day the lambs were supplemented with concentrate plus silage. Groups 1 and 2 received mixed silage made of maize, marandu palisade grass and pigeon pea and groups 3 and 4 received mixed silage made of maize and marandu palisade grass. Faecal and blood samples were taken from all the animals every two weeks, and body weight was recorded on the same occasion. Nematode faecal egg counts (FEC), packed cell volume and total plasma protein means did not differ (P > 0.05) between the four lamb groups. In 2015, throughout the experimental period, the FEC decreased in all animals, with 6733 and 1407 eggs per gram (EPG) on average at the beginning and end of the trial, respectively. At the beginning of the trial in 2016, the animals had mild GIN infections (1077 EPG on average), and the individual faecal egg counts did not exceed 10,000 EPG during the trial. In decreasing order, Haemonchus spp., Trichostrongylus spp. and Cooperia spp. third stage larvae were found in the faecal cultures in both years. The performance of lambs were similar in the four ICL systems (P > 0.05), in the first and second years, the daily weight gains were 0.192 ± 0.05 kg and 0.221 ± 0.06 kg, respectively. In conclusion, a period of withdrawal of contaminated sheep results in plots free of infective larvae. The use of clean pastures during the dry season, in the different ICL systems, associated with a good nutrition plan, resulted in progressively declining degrees of GIN infections and satisfactory daily weight gain of young sheep. Instituto de Biociências Universidade Estadual Paulista (UNESP) Faculdade de Medicina Veterinária e Zootecnia Universidade Estadual Paulista (UNESP) Instituto de Biociências Universidade Estadual Paulista (UNESP) Faculdade de Medicina Veterinária e Zootecnia Universidade Estadual Paulista (UNESP) FAPESP: #2013/13702-3 FAPESP: #2013/23853-9 FAPESP: #2015/25413-1 FAPESP: #2015/25718-7 CNPq: #458225/2014-2 CNPq: #502234/2014-8

The economic losses caused by gastrointestinal nematodes are one of the biggest obstacles in the small ruminants production. Understanding the population dynamics of the infective larvae (L3) in the pasture is the key point to develop control programs, and reliable results depend on the used methodology to quantify L3 numbers. The use of the sampling directly from the pasture appears as a viable option, since it is not required the use of animals with an esophageal fistula or tracer animals, decreasing the costs involved in the study. Therefore, the present project, which had as objective evaluate the efficiency of two collection methods for quantification of L3 in the pasture, utilized 64 lambs (n = 16) allocated to four integrated crop-livestock systems (treatments) with 12 paddocks each. Pasture samples were collected every nine days. The W method consists in traversing the area in the form of a W and again an inverted W, forage samples being collected every 10 steps, and the Square method, in tossing a 0.16 m2 square to four random points within the area, the forage within the square being collected after each toss. After the forage samples had been processed, the L3 were recovered and identified. Cohen’s Kappa coefficient (k) was determined. The W-transect and Random-plot methods did not differ (p ? 0.05) with respect to the number of L3 recovered from the pasture, and a positive correlation was found between them, suggesting agreement with one another, being that when the number of L3 recovered by the W-transect method increases, the same occurs in the Random-plot technique. The Random-plot method, which is already used to collect samples of forage for chemical analyses, can also be employed to estimate the pasture contamination by L3. The W-transect and Random-plot methods showed to be important in the epidemiological study of gastrointestinal nematodes in sheep. Therefore, the use of both on the same occasions and with different purposes, with one complementing the information that is not provided by the other, may be more effective in the investigation of environmental contamination by L3 of gastrointestinal nematodes.