Außerhalb ihrer ursprünglichen Heimat in Südamerika steigt die Anzahl der Alpakas stetig an. Die Tiere erfreuen sich auch in Deutschland einer großen Beliebtheit. Aktuellen Schätzungen zufolge leben in Deutschland circa 10.000 Alpakas. Siewerden zur Wollgewinnung, sowie als Begleit- und Therapietiere in kleinen Hobbyhaltungen oder in Beständen mit einer Herdengröße von bis zu 150 Tieren gehalten. Damit verbunden werden auch zunehmende Ansprüche an die Qualität der tierärztlichen Betreuung dieser Neuweltkameliden gestellt. Die Beurteilung des Wachstums und der Entwicklung junger Alpakas bildet dabei, genauso wie im Rahmen der Zucht, eine wichtige Grundlage. Derzeit existieren nur unzureichende Informationen über den Wachstumsverlauf beim Alpaka. Bisher dienten proportional angepasste Daten vom Lama zur Orientierung. Das Ziel dieser Arbeit ist die auf morphometrischen Daten basierende Beschreibung der physiologischen Entwicklung des Skelettes und des Körpergewichtes beim Alpaka in den ersten 36 Lebensmonaten. Weiterhin soll untersucht werden, welche Faktoren Einfluss auf das Wachstum junger Alpakas haben. Die Bestimmung einer Gleichung zur Berechnung des Körpergewichtes stellt einen weiteren Schwerpunkt der Arbeit dar. Über einen Zeitraum von 12 Monaten wurden 162 Alpakas im Alter von wenigen Tagen bis zu 36 Monaten vermessen. In einem zweiwöchentlichen Rhythmus wurden 9 verschiedene Parameter bei jedem Tier erfasst: Gewicht, Widerristhöhe, Hüfthöhe, Rückenlänge, Rumpflänge, Tuberculum majus-Olecranon-Distanz (TOD), Basis patellae-Tuber ischiadicum-Distanz (BTD), Thoraxumfang und Body Condition Score. Mit Hilfe von speziell angefertigten Messschiebern, einer digitalen Waage und einem flexiblen Maßband erfolgte die Datenerhebung am stehenden Tier. Das Wachstum beeinflussende Faktoren wurden mittels Allgemeiner Untersuchung der Tiere, stichprobenartigen Kotprobenuntersuchungen, Futtermittelanalysen und vom Halter ausgefüllten Fragebögen erfasst. Die erhobenen Messwerte wurden unter Verwendung der nichtparametrischen Regression LOESS (locally weighted scatterplot smoothing) zur Erstellung von Wachstumskurven genutzt, die den durchschnittlichen Wachstumsverlauf des Körpergewichtes, sowie verschiedener Körpermaße von bis zu 36 Monate alten Alpakas darstellen. Sie ermöglichen die Beurteilung der körperlichen Entwicklung eines Alpakas. Unter Anwendung der LMS-Methode (Schiefe der Verteilung der Messwerte λ [L], Mittelwert M, Standardabweichung S) wurden Perzentilkurven von vier Parametern erstellt, die als Referenzkurven und Richtlinien zur Beurteilung der tierartspezifischen Größe und des Gewichtes genutzt werden können. Wachstumsprognosen und Rückschlüsse auf das Alter eines Alpakas sind mit Hilfe der Perzentilkurven möglich. Sowohl die Wachstumskurven als auch die Perzentilkurven lassen erkennen, dass Alpakas mit 36 Monaten noch nicht ausgewachsen sind. Die Kurven wurden anhand von Messwerten von Alpakas erarbeitet, die unter Bedingungen gehalten wurden, die keinen beziehungsweise einen minimalen Einfluss auf das Wachstum haben. Dies ist anhand der Ergebnisse der parasitologischen Untersuchungen und der Futtermittelanalysen erkennbar. Weitere Auswertungen der Messdaten zeigen, dass keine signifikanten Entwicklungsunterschiede zwischen Hengsten und Stuten beziehungsweise zwischen der Rasse Huacaya und der Rasse Suri bestehen. Ähnlich wie bei anderen Tierarten auch, eignet sich der Thoraxumfang zur zuverlässigen Berechnung des Körpergewichtes besonders gut. Eine große Korrelation besteht auch zwischen der Rumpf- beziehungsweise der Rückenlänge und dem Körpergewicht. Praktische Bedeutung haben die Erkenntnisse dieser Arbeit vor allem für Alpakazüchter und –halter, sowie für Veterinärmediziner. Die Ergebnisse bilden eine wichtige Grundlage für das Fütterungs- und Reproduktionsmanagement beim Alpaka. / The number of alpacas bred outside their natural habitat in South America increases continuously. Alpacas become more and more popular in Germany. According to recent estimates about 10.000 alpacas live in Germany. They are used for wool production, as companion animal and for therapeutic treatments. The alpacas are kept as pets in smaller groups or as livestock in herds of up to 150 animals. Due to the rising number of these camelids in Germany and more intense use, higher demands on the quality of veterinary care of alpacas occur. Knowledge and data on growth and development in young alpacas are essential for an objective health evaluation as well as for breeding management. Currently very limited information is available on growth of alpacas and the data published have been adapted by calculation using measurements performed on llamas. The primary objective of this study was to determine the physiological development of the skeleton and the body weight of alpacas from birth until 36 months of age based on morphometric data. An additional aim was to analyze factors that influence the growth of young alpacas. A third focus of this study was to generate a mathematical formula to calculate the body weight. The measurements were performed on 162 alpacas with an age ranging from the first day of life up to 36 months. For each alpaca nine different parameters were determined every two weeks: body weight, height at withers, height in the hip, thoracic circumference, length of the back, length of the trunk, Greater tubercle-Olecranon-distance (TOD), Base of the patella-Ischial tuber-distance (BTD) and body condition score. All measurements were carried out on standing animals. Three custom designed caliper gauges, a digital balance and a flexible measuring tape were used to obtain the nine parameters. Factors that influence growth were captured by clinical examination, randomized fecal samples, analysis of forage and a questionnaire completed by the breeder. Based on the data collected growth curves were developed using the nonparametric regression LOESS (locally weighted scatterplot smoothing). These curves represent the average growth pattern of body weight and various body measurements of up to 36 months old alpacas. Using theses curves the physical development of this species can be assessed. By applying the LMS-Method (skewness of the measurement distribution λ [L], mean M, coefficient of variation S) percentile curves of four different parameters have been generated. They can serve as reference curves and as guidelines for objective evaluation of species specific size and weight. Using the percentile curves a reliable prediction of growth or conclusions regarding the age of an alpaca are possible. The growth curves as well as the percentile curves show that alpacas are not mature at the age of 36 months. The curves are based upon data from alpacas who were raised under environmental conditions which have no or minimized influence on growth. This is evident in the results of the parasitological examinations and the feed analysis. Further analyses indicate that no significant differences in growth exist between males and females respectively between the two breeds Huacaya and Suri. Like in other species the thoracic circumference is particularly suitable for estimating the body weight. A strong correlation exists between body weight and the length of the trunk as well as the length of the back. The results of this study are of practical significance for alpaca owners, breeders and veterinarians. They provide a sound basis for recommendations in feeding and management of reproduction.

O objetivo deste trabalho foi avaliar o efeito do uso de volumosos com valor nutricional distinto sobre as exigências e a eficiência de uso da energia e da proteína por ovinos ½ Dorper × ½ Santa Inês, em crescimento. Para isso, 84 cordeiros, machos não castrados, foram desmamados aos 56 dias de idade (PV inicial = 18,0 ± 3,3 kg) e confinados em baias individuais, sendo distribuídos em dois grupos: VBVN cordeiros alimentados com dieta composta por volumoso de baixo valor nutricional (bagaço de cana in natura); e VAVN cordeiros alimentados com dieta composta por volumoso de alto valor nutricional (feno de coastcross). Destes, sete animais de cada grupo foram aleatoriamente selecionados e abatidos após um período de adaptação de 10 dias (animais referência). Dentre os remanescentes, 21 animais de cada grupo foram alimentados ad libitum e abatidos aos 25, 35 ou 45 kg de peso vivo (sete animais por grupo) sendo, os 28 demais animais, submetidos a dois níveis de restrição alimentar, de forma a obterem-se diferentes níveis de consumo de energia metabolizável (EM): 70 e 50% do consumo ad libitum. Foram determinadas as concentrações e as retenções corporais de gordura, nitrogênio e energia. Adicionalmente, seis animais ½ Dorper × ½ Santa Inês (PV médio = 52,3 ± 6,9 kg), machos não castrados canulados no rúmen, foram mantidos em gaiolas de estudo de metabolismo para avaliação da digestibilidade das dietas e estimativa das concentrações dietéticas de EM e do consumo de proteína metabolizável. A degradabilidade das dietas experimentais foi avaliada in vitro. O consumo de matéria seca e o ganho de peso médio diário foram mais elevados para os animais alimentados com a dieta contendo feno de coastcross. Por outro lado, melhor eficiência alimentar foi observada para aqueles alimentados com a dieta contendo bagaço de cana. Não houve efeito do nível de consumo sobre o teor de energia metabolizável da dieta, mas este foi maior na dieta contendo bagaço de cana in natura (3,18 vs 2,94). Os animais recebendo a dieta contendo bagaço de cana apresentaram maiores concentrações corporais de gordura e energia, o que foi reflexo de um maior acúmulo de gordura visceral. O uso de volumosos de baixo valor nutricional, em dietas com alta concentração energética, não resulta em incremento das exigências energéticas de mantença. No entanto, a elevação do teor de concentrado da ração resulta em aumento da eficiência de uso da energia metabolizável para ganho de peso, o que está diretamente associado à maior retenção de gordura visceral. Sob o ponto de vista da produção de carne, todavia, esta maior eficiência nutricional deve ser vista com cautela, uma vez que está relacionada à deposição de tecidos não destinados ao consumo humano. As exigências protéicas para ganho de peso de cordeiros ½ Dorper × ½ Santa Inês podem ser acuradamente preditas pelas equações do AFRC (1993). Nenhum dos sistemas nutricionais atuais, contudo, é capaz de predizer as exigências energéticas destes animais entre os 15 e 45 kg de peso corporal. / The objective of this study was to evaluate the effect of using roughages with different nutritive value on requirements and efficiency of energy and protein use of growing ½ Dorper × ½ Santa Inês sheep. For this purpose, eighty four non-castrated male lambs were weaned at 56 days of age (initial BW = 18.0 ± 3.3 kg) and penned in individual stalls, being divided into two groups: VBVN - lambs fed diet containing roughage with low nutritive value (sugarcane bagasse in natura); and VAVN - lambs fed diet containing roughage with high nutritive value (coastcross hay). From these lambs, seven animals from each group were randomly selected and slaughtered after a 10-day adaptation period (reference animals). Twenty one animals in each group were then fed ad libitum and slaughtered at 25, 35, or 45 kg of live weight (seven animals per group), and the remaining 28 animals were submitted to one of two levels of feed restriction: either 70 or 50% of the ad libitum intake. Concentrations and retentions of body fat, nitrogen, and energy were determined. Additionally, six non-castrated males (PV mean = 52.3 ± 6.9 kg), canulated in the rumen, were kept in metabolic cages to evaluate diets digestibility, and to estimate metabolizable energy concentrations of the diets and the metabolizable protein intake. Diet degradability was assessed by an in vitro assay. Dry matter intake and average daily weight gain were higher for animals fed the diet containing coastcross hay. On the other hand, better gain-to-feed ratio was observed for those fed the diet containing sugarcane bagasse. There was no effect of intake level on metabolizable energy content of the diet, but it was higher in the diet containing sugarcane bagasse (3.18 vs. 2.94). Animals receiving the diet containing sugarcane bagasse presented higher body fat and energy concentrations, as a response of a larger visceral fat deposition. Using roughages with low nutritive value in high energy diets for growing lambs, does not increases energy requirements for maintenance. However, increasing concentrate proportion in the diet improves the efficiency of metabolizable energy use for weight gain, which is directly associated with a larger retention of visceral fat. Under a meat production perspective, however, that increased nutritional efficiency should be took with caution, since it is related to the deposition of tissues not intended to human consumption. Protein requirements for growth of lambs ½ Dorper × ½ Santa Inês are accurately predicted by the AFRC (1993) equations. None of the current nutritional systems, however, is able to predict energy requirements of these animals from 15 to 45 kg of body weight.

O objetivo deste trabalho foi avaliar o efeito do uso de volumosos com valor nutricional distinto sobre as exigências e a eficiência de uso da energia e da proteína por ovinos ½ Dorper × ½ Santa Inês, em crescimento. Para isso, 84 cordeiros, machos não castrados, foram desmamados aos 56 dias de idade (PV inicial = 18,0 ± 3,3 kg) e confinados em baias individuais, sendo distribuídos em dois grupos: VBVN cordeiros alimentados com dieta composta por volumoso de baixo valor nutricional (bagaço de cana in natura); e VAVN cordeiros alimentados com dieta composta por volumoso de alto valor nutricional (feno de coastcross). Destes, sete animais de cada grupo foram aleatoriamente selecionados e abatidos após um período de adaptação de 10 dias (animais referência). Dentre os remanescentes, 21 animais de cada grupo foram alimentados ad libitum e abatidos aos 25, 35 ou 45 kg de peso vivo (sete animais por grupo) sendo, os 28 demais animais, submetidos a dois níveis de restrição alimentar, de forma a obterem-se diferentes níveis de consumo de energia metabolizável (EM): 70 e 50% do consumo ad libitum. Foram determinadas as concentrações e as retenções corporais de gordura, nitrogênio e energia. Adicionalmente, seis animais ½ Dorper × ½ Santa Inês (PV médio = 52,3 ± 6,9 kg), machos não castrados canulados no rúmen, foram mantidos em gaiolas de estudo de metabolismo para avaliação da digestibilidade das dietas e estimativa das concentrações dietéticas de EM e do consumo de proteína metabolizável. A degradabilidade das dietas experimentais foi avaliada in vitro. O consumo de matéria seca e o ganho de peso médio diário foram mais elevados para os animais alimentados com a dieta contendo feno de coastcross. Por outro lado, melhor eficiência alimentar foi observada para aqueles alimentados com a dieta contendo bagaço de cana. Não houve efeito do nível de consumo sobre o teor de energia metabolizável da dieta, mas este foi maior na dieta contendo bagaço de cana in natura (3,18 vs 2,94). Os animais recebendo a dieta contendo bagaço de cana apresentaram maiores concentrações corporais de gordura e energia, o que foi reflexo de um maior acúmulo de gordura visceral. O uso de volumosos de baixo valor nutricional, em dietas com alta concentração energética, não resulta em incremento das exigências energéticas de mantença. No entanto, a elevação do teor de concentrado da ração resulta em aumento da eficiência de uso da energia metabolizável para ganho de peso, o que está diretamente associado à maior retenção de gordura visceral. Sob o ponto de vista da produção de carne, todavia, esta maior eficiência nutricional deve ser vista com cautela, uma vez que está relacionada à deposição de tecidos não destinados ao consumo humano. As exigências protéicas para ganho de peso de cordeiros ½ Dorper × ½ Santa Inês podem ser acuradamente preditas pelas equações do AFRC (1993). Nenhum dos sistemas nutricionais atuais, contudo, é capaz de predizer as exigências energéticas destes animais entre os 15 e 45 kg de peso corporal. / The objective of this study was to evaluate the effect of using roughages with different nutritive value on requirements and efficiency of energy and protein use of growing ½ Dorper × ½ Santa Inês sheep. For this purpose, eighty four non-castrated male lambs were weaned at 56 days of age (initial BW = 18.0 ± 3.3 kg) and penned in individual stalls, being divided into two groups: VBVN - lambs fed diet containing roughage with low nutritive value (sugarcane bagasse in natura); and VAVN - lambs fed diet containing roughage with high nutritive value (coastcross hay). From these lambs, seven animals from each group were randomly selected and slaughtered after a 10-day adaptation period (reference animals). Twenty one animals in each group were then fed ad libitum and slaughtered at 25, 35, or 45 kg of live weight (seven animals per group), and the remaining 28 animals were submitted to one of two levels of feed restriction: either 70 or 50% of the ad libitum intake. Concentrations and retentions of body fat, nitrogen, and energy were determined. Additionally, six non-castrated males (PV mean = 52.3 ± 6.9 kg), canulated in the rumen, were kept in metabolic cages to evaluate diets digestibility, and to estimate metabolizable energy concentrations of the diets and the metabolizable protein intake. Diet degradability was assessed by an in vitro assay. Dry matter intake and average daily weight gain were higher for animals fed the diet containing coastcross hay. On the other hand, better gain-to-feed ratio was observed for those fed the diet containing sugarcane bagasse. There was no effect of intake level on metabolizable energy content of the diet, but it was higher in the diet containing sugarcane bagasse (3.18 vs. 2.94). Animals receiving the diet containing sugarcane bagasse presented higher body fat and energy concentrations, as a response of a larger visceral fat deposition. Using roughages with low nutritive value in high energy diets for growing lambs, does not increases energy requirements for maintenance. However, increasing concentrate proportion in the diet improves the efficiency of metabolizable energy use for weight gain, which is directly associated with a larger retention of visceral fat. Under a meat production perspective, however, that increased nutritional efficiency should be took with caution, since it is related to the deposition of tissues not intended to human consumption. Protein requirements for growth of lambs ½ Dorper × ½ Santa Inês are accurately predicted by the AFRC (1993) equations. None of the current nutritional systems, however, is able to predict energy requirements of these animals from 15 to 45 kg of body weight.