A 2-year winter grazing and feedlot finishing trial (Exp 1) and subsequent in-situ nutrient disappearance study (Exp 2) were conducted to evaluate the effects of swath grazing forage barley (Hordeum vulgare, cv. Ranger) or foxtail millet (Setaria italica, cv. Golden German) compared to grass-legume hay fed in drylot on calf performance. In trial1 in each of 2 years, 120 spring born Angus calves (60 steers, 60 heifers) were fall weaned, stratified by weight, allocated into 20-head groups then assigned randomly to one of the three replicated (n=2) backgrounding (BG) systems. Backgrounding systems were (i) swath graze barley (BR); (ii) swath graze millet (ML); and (iii) bunk fed ground hay drylot (DL). Swath grazed calves were limit fed in 8 ha paddocks with 3 d grazing periods, using electric fencing for 96 d each year. All groups received a pelleted supplement at 0.62% BW. Calves were weighed at start, every 21 d and end of background period. Following the BG period, calves were placed in feedlot, separated by sex and BG treatment and fed a similar finishing ration and harvested at a targeted endpoint of 12 mm back fat. Forage samples collected every 21 d were analyzed for DM, CP and digestible energy (DE) and change in nutritive quality over the grazing period. DE content was greatest (P<0.05) for BR (2.6 Mcal/kg) and least for DL hay (2.2 Mcal/kg). Quality of all the three forages did not change over the grazing period except for an increase (P<0.05) in NDF of millet. Calf ADG was greatest (P <0.05) for BR compared to ML or DL, while dry matter intake (DMI) of the BR calves tended to be greater (P=0.11) than ML or DL calves. No treatment differences were observed in the finishing ADG (P>0.05) and carcass characteristics (P>0.05) of calves from the three backgrounding systems. In Exp 2, four dry ruminally cannulated Holstein cows fed ground grass hay were used in an in-situ degradability study to determine the extent of degradation and rumen kinetic parameters of the 3 forages used in Exp 1. Effective degradability of DM and CP iii were similar for barley and millet and greater (P<0.05) than grass legume hay while NDF degradability (P<0.05) of millet was greater than that of barley or grass legume hay. These findings indicate that swath grazing barley or foxtail millet fed to beef calves resulted in similar or decrease performance compared to a traditional drylot pen system. Cost of gain for the barley swath grazed backgrounding system calves was 43 and 60.5% lower compared to a swath grazed millet or drylot system, respectively. The economics of these systems would indicate that backgrounding of calves on swath grazed barley is a more efficient and low cost system compared to drylot.

A 2-year winter grazing and feedlot finishing trial (Exp 1) and subsequent in-situ nutrient disappearance study (Exp 2) were conducted to evaluate the effects of swath grazing forage barley (Hordeum vulgare, cv. Ranger) or foxtail millet (Setaria italica, cv. Golden German) compared to grass-legume hay fed in drylot on calf performance. In trial1 in each of 2 years, 120 spring born Angus calves (60 steers, 60 heifers) were fall weaned, stratified by weight, allocated into 20-head groups then assigned randomly to one of the three replicated (n=2) backgrounding (BG) systems. Backgrounding systems were (i) swath graze barley (BR); (ii) swath graze millet (ML); and (iii) bunk fed ground hay drylot (DL). Swath grazed calves were limit fed in 8 ha paddocks with 3 d grazing periods, using electric fencing for 96 d each year. All groups received a pelleted supplement at 0.62% BW. Calves were weighed at start, every 21 d and end of background period. Following the BG period, calves were placed in feedlot, separated by sex and BG treatment and fed a similar finishing ration and harvested at a targeted endpoint of 12 mm back fat. Forage samples collected every 21 d were analyzed for DM, CP and digestible energy (DE) and change in nutritive quality over the grazing period. DE content was greatest (P<0.05) for BR (2.6 Mcal/kg) and least for DL hay (2.2 Mcal/kg). Quality of all the three forages did not change over the grazing period except for an increase (P<0.05) in NDF of millet. Calf ADG was greatest (P <0.05) for BR compared to ML or DL, while dry matter intake (DMI) of the BR calves tended to be greater (P=0.11) than ML or DL calves. No treatment differences were observed in the finishing ADG (P>0.05) and carcass characteristics (P>0.05) of calves from the three backgrounding systems. In Exp 2, four dry ruminally cannulated Holstein cows fed ground grass hay were used in an in-situ degradability study to determine the extent of degradation and rumen kinetic parameters of the 3 forages used in Exp 1. Effective degradability of DM and CP iii were similar for barley and millet and greater (P<0.05) than grass legume hay while NDF degradability (P<0.05) of millet was greater than that of barley or grass legume hay. These findings indicate that swath grazing barley or foxtail millet fed to beef calves resulted in similar or decrease performance compared to a traditional drylot pen system. Cost of gain for the barley swath grazed backgrounding system calves was 43 and 60.5% lower compared to a swath grazed millet or drylot system, respectively. The economics of these systems would indicate that backgrounding of calves on swath grazed barley is a more efficient and low cost system compared to drylot.

Master of Science / Department of Animal Sciences and Industry / Joel M. DeRouchey / Five experiments using a total of 4,470 pigs were used to determine the effects of dietary Cu and Zn source and finishing pig space allowance. Experiment 1 evaluated increasing dietary Zn from Zn hydroxychloride or ZnSO₄ for finishing pigs. Increasing dietary Zn up to 100 mg/kg Zn maximized ADG and HCW with the greatest response observed during the last 37 d period when ractopamine was included in the diet. Pigs fed diets with Zn hydroxychloride had greater HCW compared to those fed ZnSO₄. Experiment 2 evaluated increasing dietary Cu from either CuSO₄ or a 50:50 blend of CuSO₄:Cu-AA for finishing pigs. Pigs fed Cu from CuSO₄ alone consumed more feed and tended to have poorer feed efficiency than those fed a 50:50 blend of Cu from CuSO4:Cu-AA. Pigs fed a 50:50 blend of CuSO4:Cu-AA had improved HCW G:F but ADG was unchanged on a live and HCW basis. Experiments 3 and 4 evaluated increasing dietary Cu from tri-basic copper chloride or a Cu-chelate for nursery pigs. In Exp. 3, increasing Cu from Cu-chelate to 150 mg/kg Cu increased ADG and ending BW. Increasing Cu to 150 mg/kg Cu increased ADFI and improved G:F. Pigs fed Cu from Cu-chelate had greater ADG, ADFI and ending BW than those fed Cu from tri-basic copper chloride. In Exp. 4, increasing Cu to 225 mg/kg Cu increased ADG and ending BW. Because ADFI was unchanged, G:F tended to be improved as Cu level increased. There were no differences detected between Cu sources for growth performance. Experiment 5 was conducted to determine the effects of increasing space allowance by pig removal or gate adjustment during the finishing period. Pigs provided 0.91 m² had increased ADG compared with those allowed 0.63 m² with pigs from pens provided increased space intermediate. Pigs provided 0.91 m² had increased ADFI compared with pigs allowed 0.63 m² and those where a pig was removed; however, pigs from pens where the gate was adjusted were intermediate. As pigs grew to the minimum predicted space requirement and were subsequently allowed more space, performance was greater than those initially provided 0.61 m² but less than those allowed 0.91 m².

MSCAGR (Animal Science) / One of the ways to minimise cost and promote health in humans and animals is to use natural feed additives instead of antibiotics. Moringa oleifera (Moringa) is a phytobiotic which possess anti-microbial and immune-modulatory properties and contains high levels of nutrients and it can be used as a feed additive. Probiotics are feed additives which consist of living microorganisms that have beneficial effects on the physiology and health of other organisms. The objective of the study was to determine the effect of various levels of Moringa oleifera and probiotics inclusion on growth performance, carcass characteristics and cost benefit analysis for broiler chicken production. Moringa oleifera leaf powder was purchased from Bethel Farm No:683 Bethel mission Gucksdadt Vryheid in Zululand district AbaQulusi municipality. The study was a 5x2 factorial design with five levels of Moringa and two levels of probiotic. Six hundred (600) Ross 308-day old chicks were received and fed commercial starter. The experimental treatments were randomly divided into five levels of Moringa with and without probiotics introduced through drinking water at grower to finisher phase. The diets were supplemented with different inclusion levels of Moringa (Mo) as follows: 0g/kg (M0), 0.6g/kg (M3), 1.2g/kg (M6), 1.8g/kg (M9), 2.4g/kg (M12) of Moringa oleifera leaf meal (MOLM) and probiotic at P0 (0ml/bird/week), P1 (1 ml/bird/week) of a commercial probiotic administered in water for the first three weeks (starter phase). The experiment had three replications with 20 birds per replicate. MOLM and PRB interaction had no significant effect (P>0.05) on any of growth parameters and same findings with MOLM. Probiotics treatments had significantly reduced (P < 0.05) mortality rate (MTRT) in the grower phase. MOLM×PRB had significant effect on (P<0.01) feed intake (FI), MOLM had significantly reduced (P< 0.05) average bodyweight gain (ABWG) and FI in finisher phase. MOLM and PRB interaction had significant effect (P< 0.05) on dressed weight only and non-significant effect (P>0.05) on the rest of carcass parameters. MOLM inclusion levels did not significantly affect (P>0.05) back fat weight. However, MOLM inclusion level significantly reduced (P< 0.05) dressed weight, shank length, wing weight, drum and thigh weight, back weight and breast muscle weight. PRB inclusion in the diets significantly increased (P< 0.01) shank size and drum + thigh weights (P<0.05). MOLM and PRB inclusion level had no significant effect (P>0.05) on giblets parameters. MOLM and PRB interaction had significant effect on (P<0.05) water holding capacity (WHC) and hardness. MOLM had significant effect (P<0.05) on pH and dripping loss. A significant effect between (MOLM×PRB) Moringa oleifera leaf meal and probiotics (P<0.01) was observed on CD, C* and b*. MOLM had significant effect (P<0.01) on CD, C*, a*, b*, L*, PRB had significant effect (P<0.01) on h*(increased) and a*(reduced) on colour parameters. MOLM fed at P0 resulted in higher mortality at grower stage. It is concluded that MOLM can be added up to 12% with or without PRB without affecting growth performance at finisher phase and carcass characteristics. Inclusion of MOLM up to 12% had good impact on hardness and water holding capacity in the meat. PRB presence improved the growth performance of birds supplemented with MOLM up to 12% inclusion level. MOLM diets were not economically profitable compared to control diet due to high price level of Moringa oleifera powder supplemented in the diets and no best return weight gain per rand invested amongst the diets. / NRF

Master of Science / Department of Animal Sciences and Industry / Joel M. DeRouchey / Five experiments using a total of 4,470 pigs were used to determine the effects of dietary Cu and Zn source and finishing pig space allowance. Experiment 1 evaluated increasing dietary Zn from Zn hydroxychloride or ZnSO4 for finishing pigs. Increasing dietary Zn up to 100 mg/kg Zn maximized ADG and HCW with the greatest response observed during the last 37 d period when ractopamine was included in the diet. Pigs fed diets with Zn hydroxychloride had greater HCW compared to those fed ZnSO4. Experiment 2 evaluated increasing dietary Cu from either CuSO4 or a 50:50 blend of CuSO4:Cu-AA for finishing pigs. Pigs fed Cu from CuSO4 alone consumed more feed and tended to have poorer feed efficiency than those fed a 50:50 blend of Cu from CuSO4:Cu-AA. Pigs fed a 50:50 blend of CuSO4:Cu-AA had improved HCW G:F but ADG was unchanged on a live and HCW basis. Experiments 3 and 4 evaluated increasing dietary Cu from tri-basic copper chloride or a Cu-chelate for nursery pigs. In Exp. 3, increasing Cu from Cu-chelate to 150 mg/kg Cu increased ADG and ending BW. Increasing Cu to 150 mg/kg Cu increased ADFI and improved G:F. Pigs fed Cu from Cu-chelate had greater ADG, ADFI and ending BW than those fed Cu from tri-basic copper chloride. In Exp. 4, increasing Cu to 225 mg/kg Cu increased ADG and ending BW. Because ADFI was unchanged, G:F tended to be improved as Cu level increased. There were no differences detected between Cu sources for growth performance. Experiment 5 was conducted to determine the effects of increasing space allowance by pig removal or gate adjustment during the finishing period. Pigs provided 0.91 m2 had increased ADG compared with those allowed 0.63 m2 with pigs from pens provided increased space intermediate. Pigs provided 0.91 m2 had increased ADFI compared with pigs allowed 0.63 m2 and those where a pig was removed; however, pigs from pens where the gate was adjusted were intermediate. As pigs grew to the minimum predicted space requirement and were subsequently allowed more space, performance was greater than those initially provided 0.61 m2 but less than those allowed 0.91 m2.

The objective of this study was to examine the effects of 70% (DM) inclusion of dried distillers' grain with solubles (DDGS) on performance and meat quality. Ninety-six Angus steers (276 kg ± 7.5 kg initial BW) were used in an completely randomized design with incomplete replication. Steers were stratified by BW to pens and pens were randomly assigned to one of 6 treatments: 1) 80% corn; 5% soybean meal; 15% corn silage, fed as a negative control (CON); 2) 40% DDGS: 45% corn: 15% corn silage, fed as a positive control (PCON); 3) steers received PCON (0-84d) then switched to a diet of 70% DDGS: 15% corn: 15% corn silage until finished (40/70); 4) steers started on 70% DDGS: 15% corn: 15% corn silage (0-84d) then switched to PCON until finished (70/40); 5) CON + soybean meal, isonitrogenous to PCON (N40); 6) CON + corn oil, isocaloric to PCON (E40). Steers were fed respective treatments until 80% of them reached low choice or higher by visual appraisal, providing their genetics allowed (168 and 213 days). Dry matter intake, DMI, (P &ge 0.82) was not affected by treatment, isocaloric, or isonitrogenous diets. End weight was greater (P = 0.04) for PCON steers compared to N40 steers. However, no treatment effect (P &ge 0.15) on G:F. Dietary treatment did not affect HCW, quality grade, %KPH, or liver score (P &ge 0.12). Yield grade was not affected (P = 0.12) by treatment but tended to be lower (P = 0.06) for N40 steers compared to PCON steers. However, N40 steers had a larger (P = 0.04) ribeye area and greater rib fat (P = 0.05) when compared to PCON and ribeye tended (P = 0.06) to be smaller in 70/40 and E40 steers compared to all other treatments. Minotola color, % cook loss, shear force, total SFA, total PUFA, total MUFA or lipogenic activity were not affected (P &ge 0.08) by treatment. The data of this study suggests that it is possible to feed 70% DDGS in feedlot rations with little to no adverse effects on growth performance or meat quality.

The objective was to determine how the interaction of implant strategies with the galanin receptor 2 genotype would influence feeding behavior, production efficiencies, carcass characteristics, and meat quality in finishing steers. Angus steers were selected based on GALR2-c.-199T>G genotype (n = 36 TT, 38 TG, and 19 GG). Calves were blocked by body weight and fed a standard feedlot ration, blood and BW were collected every 28 d. Steers were randomly assigned to an implant strategy of Revalor-S (1×) or Revalor-S (2×). Intake and feeding behavior data were individually recorded. There was an effect of genotype on DMI but not feed efficiency. Treatment interactions were observed for several meat quality attributes but not carcass characteristics. Altering implant strategy does not appear to interact with the GALR2-c.-199T>G genotype to alter production or carcass characteristics.

Doctor of Philosophy / Department of Animal Sciences and Industry / Joe D. Hancock / Twelve experiments were completed to evaluate corn- and sorghum-distillers dried grains with solubles (DDGS) in diets for nursery and finishing pigs. In Exp. 1, corn-DDGS had 223 kcal/kg greater DE than sorghum-DDGS (P<0.02). In Exp. 2, pigs fed a corn-soy control diet had greater ADG, nutrient digestibility, HCW, and dressing percentage (P<0.02) and lower iodine value (IV) of jowl fat (P<0.001) than pigs fed diets with 40% DDGS. High-energy DDGS supported lower ADG, ADFI, and digestibility of DM (P<0.06) than moderate-energy DDGS, and sorghum-DDGS resulted in lower IV than corn-DDGS (P<0.001). In Exp. 3 and 4, addition of sodium bicarbonate to adjust dietary pH and electrolyte balance did not improve growth performance in nursery or finishing pigs (P>0.16) and adding molasses to improve palatability decreased (P<0.05) G:F for finishing gilts. In Exp. 5 and 6, enzyme additions improved nutrient digestibility in nursery (P<0.04) and finishing (P<0.01) pigs fed diets with high inclusion of DDGS. In Exp. 7, expander processing improved (P<0.02) ADG, G:F, and digestibility of DM, N, GE, and cellulose compared with standard steam conditioning of diets for nursery pigs, with the greatest response in G:F for pigs fed sorghum-DDGS (DDGS source × conditioning; P<0.02). In Exp. 8 and 9, expander conditioning improved G:F and dressing percentage (P<0.007) and digestibility of DM, N, and GE compared with standard conditioning (P<0.02), with the greatest response in digestibility of DM for the DDGS diets (diet × conditioning, P<0.01). In Exp. 10, 11, and 12, increasing tallow from 0 to 5% in diets with 40% DDGS improved (P<0.05) G:F. Dressing percentage was improved with addition of tallow and palm oil (P<0.08), but IV become worse (linear, P<0.06) as tallow was increased in the diet. Adding coconut oil improved growth performance and carcass firmness in pigs fed diets with 40% DDGS (P<0.01). In conclusion, growth performance and nutrient digestibility decreased with addition of DDGS to diets for nursery and finishing pigs. However, adding enzymes partially restored nutrient digestibility; expander conditioning improved G:F, dressing percentage, and nutrient digestibility; and adding coconut oil to diets with 40% DDGS improved G:F and carcass firmness.

There is a growing market for specialty poultry production using alternative genotypes and management systems. However, producers interested in specialty poultry production face several challenges. One challenge is that little published data exists regarding the growth and production parameters for alternative genotypes like slow-growing meat strains and heritage breeds. To address this challenge, research at the University of Kentucky examined the effect of feed strategies, alternative feedstuffs, and dietary enzymes on the growth and performance of heritage breeds of chicken used for either egg- or meat-production. The first trial documented the growth and nutrient intake of pullets from three heritage breeds (Rhode Island Red, Barred Plymouth Rock, and Black Australorp) and three egg-laying strains (Red Star, Black Star, and ISA Brown) on a self-selection feeding program through nineteen weeks of age. The second trial documented the growth and nutrient intake of males from those same three heritage breeds, a slow-growing meat-type strain (Red Ranger), and males and females from a fast-growing meat-type strain (Cornish Cross). Birds used a self-selection feeding program and were grown to a common weight of 2300 grams. Carcass characteristics of these birds were evaluated in the third trial. The fourth trial evaluated the partial replacement of corn and soybean meal with alternative feedstuffs (field peas, buckwheat, and flax seed) and dietary enzymes on the performance of straight-run commercial broilers and two alternative breeds of chickens: males from a Black Sex-Link cross and straight-run Rhode Island Reds. The fifth trial examined the use of sorghum and field peas to completely replace corn and soybean meal in formulated diets for two heritage breeds (Rhode Island Red and Barred Plymouth Rock). Results of these trials showed that heritage breed pullets had similar growth parameters and nutrient intake as commercial egg-laying strains. Heritage breed cockerels grew significantly slower and exhibited poorer feed efficiency than meat-type birds, but seemed to tolerate low nutrient density diets better. Overall, the findings of these studies could help producers interested in raising slow-growing meat-type chickens and heritage breeds create accurate business plans and determine if they can profitably produce meat and/or eggs for niche markets.

Fontes de lipídios para animais em confinamento vem sendo testadas para melhorar o desempenho animal. Neste sentido, este trabalho avaliou o desempenho animal, as características da carcaça e da maciez da carne de 36 novilhos mestiços (aproximadamente ¾ Bos taurus taurus, filhos de vacas cruzadas Simental x Nelore com touros Brangus), com idade e pesos vivos médios de 14 meses e 320 kg, respectivamente. O experimento foi realizado no setor de Bovinocultura da FZEA, USP, onde foram avaliadas três dietas com 81% de concentrado, sendo uma ração com 5% de gordura protegida (GP), uma ração com 21% de caroço de algodão (CA) e uma ração controle (CT) sem gordura adicional. A ingestão de matéria seca com a ração GP foi menor (P<0,05) que a ingestão com a ração CA, que não diferiu da ração CT, sem que o ganho médio diário e a eficiência alimentar apresentassem diferenças significativas entre os tratamentos. Os valores encontrados para a análise de uréia sangüínea estiveram dentro do considerado normal, havendo um valor significativamente maior para o tratamento CA em relação ao tratamento GP. O rendimento de carcaça, a área de olho de lombo, a espessura de gordura, a gordura renal e pélvica e o peso do fígado não foram significativamente diferentes. Os índices de pH e temperatura, tanto na primeira hora após o abate como 24 horas depois, não foram significativamente diferentes e os valores encontrados estão dentro do esperado. O índice de perda de água no cozimento não foi significativamente diferente entre os tratamentos, o mesmo ocorrendo com a análise de maciez, verificada através das forças de cisalhamento nos diferentes tempos de maturação. Os valores entre 3,0 e 3,5 kg encontrados neste trabalho correspondem a uma carne muito macia, que ainda poderia ser melhorada com a maturação por 14 dias. A gordura protegida a 5% e o caroço de algodão a 21% podem ser empregados nas rações de confinamento sem que alterem o desempenho animal ou a carcaça, sempre que o preço destes ingredientes for economicamente vantajoso. / Several fat sources have been utilized in feedlot diets to improve animal performance. This study carried out at the Beef Cattle Sector of the FZEA, USP, evaluated the performance and carcass and meat characteristics of 36 crossbred steers (approximately ¾ Bos taurus taurus, offspring of crossbred Simental cow x Brangus sire), with 14 months old on the average and 320 kg, fed diets with 81% concentrate and 5% protected fat (GP), or 21% whole cotton seed (CA), or without any additional fat (CT). The dry matter intake of the GP diet was lower than with the CA diet, which was not different from the CT diet, but with no effect on daily weight gain and feed efficiency. Blood urea nitrogen was greater for the CA treatment than GP treatment, but in the normal range. Carcass dressing, rib eye area, fat thickness, kidney and pelvic fat, and liver weight were not different among treatments. The pH and temperature in the first hour and after 24 hours of chilling were not different and in the normal range. There was also no difference among treatments in water loss during cooking and Warner Bratzler shear force. The shear force values ranged from 3.0 to 3.5 kg, but were improved after 14 days of maturation. The resulted indicated that the protected fat or whole cottonseed can be used as ingredients for feedlot diets without affecting performance or carcass characteristics, if economically feasible.